DIYstompboxes.com

DIY Stompboxes => Building your own stompbox => Topic started by: Izzy on October 08, 2006, 07:37:55 PM

Title: Need help building Ibanez Tube screamer.
Post by: Izzy on October 08, 2006, 07:37:55 PM
Hi guys,
I want some help to start my seconn project Ibanez Ts808 or Ts9.
I have been doing lots of reading these days from this forum and printing stuff from here and Geofx. I have definately learned a lot after my first MXR distortion project.

Before I start my project I need to ask few things.


1>
I have these 3 schematics of TS 808 or TS9
But second and third schematics have big thing attached at the bottom of the circuit which is not included in first schematic. Why is that
I am trying to follow according to First circuit which I got from Tonepad.


First Schematic :
http://img365.imageshack.us/img365/6855/creamerwg0.jpg


Second Schematics:
http://img365.imageshack.us/img365/3417/ts808fq0.jpg

Third Schematics:
http://img365.imageshack.us/img365/5913/ibnztubescreamerce6.jpg



2>
What is this Vbin first schemtic?I it the 4.5 volt ?



3>
I dont understand why Tube screamer is using LINEAR pot for Volume? Isnt it supposed to be  Log for smooth volume control?
And since i always use drive, around 50-100% , can I use Reverse log?  So that it ill give me chance to fine tune the drive. Or is Log pot better option to use here?

4>What is the main diff between TS808 and TS9? As far As i can see there are only few changes like 2-3, Is that it? I thought there was huge different.
IF there's not huge differnce then why do peopl still go for ts 808?
Can some body explain??


I would really appreciate if someone would answer these question.
Hopefully Gibson GM again to the rescue. :D









Title: Re: Need help building Ibanez Tube screamer.
Post by: zyxwyvu on October 08, 2006, 08:36:44 PM
The large part at the bottom of the second two schematics is the electronic switching. You don't need to include any of that - it can be replaced by a simple DPDT switch.

In the first schematic, Vb is 4.5 V. You can tell from the part in the upper right, where there is a voltage divider (2x 10k resistors), and a smoothing capacitor (47uF).

You are correct that there are only a couple differences between the TS9 and TS808. In the first schematic, the changes are to the resistors marked Ra and Rb (also in red). Take a look at http://beavisaudio.com/Projects/ScreamerLab/ (http://beavisaudio.com/Projects/ScreamerLab/). There, the builder uses two switches to change it from TS9 to TS808. I don't think there is a big difference in tone, but I haven't tried it, so I could be wrong.
Title: Re: Need help building Ibanez Tube screamer.
Post by: fixr1984 on October 08, 2006, 09:48:28 PM
From what I understand the Ts-9 was made more for the
SS amp users and the TS-808 was more for the tube amp users.
Do you use strip board? If you do Here (http://aronnelson.com/gallery/album28/screamer) is a layout from
Torchy's gallery. I made mine from this layout and It works great.
Unless you are looking at taking the schematic and making your own
layout. If thats the case have you checked out Bancika's layout program yet?
It works great. Link (http://www.diystompboxes.com/smfforum/index.php?topic=44838.0) The program can be found
by clicking on the box in his signature. Hope this helps.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 08, 2006, 10:27:37 PM
Super thanks to both of you. Awesome help.!

I was looking for stripboard but couldnt find in smallbearelectronics. neither in radio shack. So I think I will go with this
http://www.radioshack.com/product/index.jsp?productId=2103800&cp=&origkw=breadboard&kw=breadboard&parentPage=search


I am thinking of following first schematic. But I was not sure whether to go for TS9 or TS 808. So why does TS 808 has such a great value when the changes between these two are just minor? Is there a  BIG difference in tone? Or am I missing some thing here?
If there is a big difference in tone then I will probably use dpdt to switch between TS-9 and TS808.

And also my third question remains unanswered, can some one explain?
Quote
3>
I dont understand why Tube screamer is using LINEAR pot for Volume? Isnt it supposed to be Log for smooth volume control?
And since I always use drive, around 50%-100% , can I use Reverse log?  So that it will give me chance to fine tune the drive aaround 50-100%. Or is Log pot better option to use here

Waiting for help...



Title: Re: Need help building Ibanez Tube screamer.
Post by: fixr1984 on October 08, 2006, 11:15:54 PM
I'm not sure myself about the volume pot. The link I gave you
to Torchy's layout has a log pot for the volume.
Check out the "store" link on the top of the screen. Aron sells all sorts of stuff there
including strip board.  I found This (http://www.diystompboxes.com/smfforum/index.php?topic=42924.0) It would appear that the
resistor change effects the output buffer changing the output impedence.
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 09, 2006, 09:42:16 AM
why does TS 808 has such a great value when the changes between these two are just minor? Is there a  BIG difference in tone? Or am I missing some thing here?
  Try both, then spend a great value on a 'vintage mojo' TS, and find that the control pots allow enough variance to compensate for the small component tolerance differences...go with the sound you like..or spend big to find out for sure how important mojo isn't.
  Minor differences = Big Mojo [if you have it, and can sell it, without losing it].
  Either log or linear will provide a variable divider for the volume, you might like one taper better than the other because control will be bunched up at one end of the pot, the rest of the rotation won't do much. I just look for Log first when wiring a volume control.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 11:17:55 AM
hey hanks pete more for your reply.

Basically thats what I was thinking.Log pot for Volume, since it will give smooth volume increment. And Reverse log pot for drive because I always use high drive setting so reverse log should allow me to fine tune higher drives more easily than log pot ? Am I right?

And One more thing I just bought 2 striop board from Aron's store. This will be my first time using  stripboard. So I wanted to know do I need to but strip board cutter? Or can I use some thing else for cutting strip board?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 11:57:27 AM
1>
One more question

As per FAQ page it says:
Quote
In a nutshell, you should use electrolytic when the capacitor is polarized. You can also use tantalum capacitors instead of electrolytic, but these are not commonly used. For any others, the basic consensus is to use film caps if they fit, otherwise use a mixture of film and ceramic capacitors. For most of our circuits, use caps with a minimum 16 volt rating. R.G. posted a great explanation about the subjective world of capacitors. For distortion circuits, others have noted that cheap ceramics sound good too, so use your ears! In general, 1uF and up will be electrolytic, any smaller values up to .001uF can be film types and picofarad values like 10pf-470pf are usually ceramic types. This is usually due to size, cost and availability. With the exception of elecrolytic and tantalum capacitors, most capacitors such as film or ceramic are non-polarized (often labeled NP). The orientation of a non-polarized capacitor doesn't matter; there's no positive or negative.



I need 2 x 1uf (NP) caps for this project. But the faq page says :

Anything from 1uf and above should use Electrolytic caps.
Also where it is labeled NP caps it shouldnot be replaced with Electrolytic(Polarised) caps .

So what should I go for?Metal film caps?



2>
Another question.
In smallbear electronics. they have this thing :
Quote
Capacitors, Low Voltage Poly Film
Capacitors, Xicon High Voltage Poly Film
Capacitors, Mallory 150 Series Poly Film
Capacitors, Sprague 715 Series, Orange Drop
Capacitor, Sprague 716 Series, Orange Drop
Capacitors, Silver Mica

I am kinda confused , Am I supposed to choose high voltage or low voltage?
Isnt there any metal film caps in small bear?

Or I found this
http://www.smallbearelec.com/Detail.bok?no=191
So can I use this where it is labeled 1uf (NP) in schematics?


3>
Looks like most of capacitor there in smallbear are POLY film. I am kinda scared to buy poly film , because I am new to soldering and I am afaraid I might damage the cap with heat?
What should I do?



Waiting for reply.....
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 01:16:20 PM
Gibson GM, Aron, Mike hammer or can anyone answer to my questions kindly?
Title: Re: Need help building Ibanez Tube screamer.
Post by: ubersam on October 09, 2006, 02:36:39 PM
1>I need 2 x 1uf (NP) caps for this project. But the faq page says :

Anything from 1uf and above should use Electrolytic caps.
Also where it is labeled NP caps it shouldnot be replaced with Electrolytic(Polarised) caps .

So what should I go for?Metal film caps?
Poly/metal film caps would be bigger than their electrolytic counterparts. However, some would be small enough to use depending on the board's layout. On a BYOC TS clone pcb for instance, the spot for the 1uf cap is big enough for either a CDE (Cornell-Dubilier) 1uf film cap, or an AVX BN series boxed film cap (both have 15mm lead spacing).


2>
Another question.
In smallbear electronics. they have this thing :
Quote
Capacitors, Low Voltage Poly Film
Capacitors, Xicon High Voltage Poly Film
Capacitors, Mallory 150 Series Poly Film
Capacitors, Sprague 715 Series, Orange Drop
Capacitor, Sprague 716 Series, Orange Drop
Capacitors, Silver Mica


I am kinda confused , Am I supposed to choose high voltage or low voltage?
Isnt there any metal film caps in small bear?
You are supposed to choose the voltage that would accomodate the requirements of your project. In the case of the TS, that would be 9VDC. So, as long as the device can handle 9VDC, it should be O.K. If you can find the necessary cap in a 16VDC or 25VDC rating, use that. I personally could not find any film caps with a voltage rating lower than 100VDC . I have been using ones that are rated for 100VDC or 250VDC and theyworked fine in the TS.

The Sprague Orange Drops are going to be huge, well, significanly bigger than other metal/poly film caps.

The silver mica caps would be in the pf range. I used silver mica in the feedback loop of the TS (in parallel with the clipping diodes).
 
3>
Looks like most of capacitor there in smallbear are POLY film. I am kinda scared to buy poly film , because I am new to soldering and I am afaraid I might damage the cap with heat?
What should I do?
Just practice your soldering skills. If you are judicious with how long you are applying heat to a component's lead, a few seconds and not minutes, you wouldn't damage the poly film caps. (Polystyrene caps would be a different story) You could also use heatsink clips on the leads if you find it necessary.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 03:18:33 PM
Thanks for you help. I appreaciate.

I am hoping someone would answer this question
1>
I need 2 x 1uf (NP) caps for this project. But the faq page says :

Quote
Anything from 1uf and above should use Electrolytic caps.
Also where it is labeled NP caps it shouldnot be replaced with Electrolytic(Polarised) caps .

So what should I go for?Metal film caps?


I found this
http://www.smallbearelec.com/Detail.bok?no=191
So can I use this where it is labeled 1uf (NP) in schematics?



Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 09, 2006, 04:33:55 PM
I need 2 x 1uf (NP) caps for this project. But the faq page says :
Anything from 1uf and above should use Electrolytic caps.
  Larger than 1uf values of caps are available in the Electrolytic typs and Tantalum mostly [I didn't really look much at metals...] for where it calls for these values I use Electrocaps, other types tend to be LarGer and not fit, or are not available in the large values.
Also where it is labeled NP caps it shouldnot be replaced with Electrolytic(Polarised) caps .

  You can make a non-polarized [bi-polar actually], using two electrolytic polarized caps, connect the + of one to the - of the other, the + of the other to the plus of the one...
I am kinda confused , Am I supposed to choose high voltage or low voltage?
  ..try..to never exceed the rated value of a capacitor [labeled on the side of electro's], since you'll be running TS @ 9v, you want that as minimum cap rating +10%-20%...to be on the safe side. Use caps rated 16v or more.
So what should I go for?Metal film caps?
..expensive.
  I don't like ceramics, I use poly's all the time.
Looks like most of capacitor there in smallbear are POLY film. I am kinda scared to buy poly film , because I am new to soldering and I am afaraid I might damage the cap with heat?
  Anything with a diode in it is first on the 'don't overheat list' [transistors diodes, opamps], I've exposed alot of caps to high heat, never had a failure as a result.
  I use sockets or heat sink each lead above board with a testclip when directly soldering in actives. Always use socket for opamps.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 05:23:03 PM
Thanks petemore. So that mean Polycaps should be able to bear some heat while soldering.right? I though they would melt. ;D

Ok but my electrolyic caps question still remains unanswred ;D
Let me rephrase it.

Can I use this NP electrolytic caps where it is labeled 1uf (NP) in schematics?
http://www.smallbearelec.com/Detail.bok?no=191

The reason I was confused was. I need 1uf caps at the same time it has to be NP. But accroding to FAQ page, If 1uf = use Electrolytic , If NP = dont use electrolytic.
My condidtion satisfies the both situation i.e 1uf NP. So I was like ???
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 06:10:35 PM
I am going to buy all the parts from Smallbear. But before I hit ORDER button I want to make sure, everything is right.

can anyone check?

 0901 Resistor 1/4-Watt 5% Carbon Film, 120 Ohms to 1K
(1K) $0.15  $0.75
 0904 Resistor 1/4-Watt 5% Carbon Film, 43K to 220K
(51K) $0.15  $0.30
 0902 Resistor 1/4-Watt 5% Carbon Film, 1.1K to 6.2K
(4.7K) $0.15  $0.30
 0905 Resistor 1/4-Watt 5% Carbon Film, 240K to 1Meg
(510K) $0.15  $0.45
 0906 Resistor 1/4-Watt 5% Carbon Film, 1.1Meg to 22Meg
(2.2Meg) $0.15  $0.30
 0903 Resistor 1/4-Watt 5% Carbon Film, 6.8K to 39K
(10K) $0.15  $0.75
 0901 Resistor 1/4-Watt 5% Carbon Film, 120 Ohms to 1K
(220 ohms) $0.15  $0.30  



 2006 Transistor 2N3904
 $0.25  $0.50 
0707 Socket, Transistor, Mill-Max TO-5
 $0.60  $1.20  



 1507 IC JRC4558D
 $0.45  $0.90
 0703 Socket, IC, Dual-Leaf, AMP 8-pin
 $0.45  $0.90  



 0600A Jack, 1/4 in. Mono Neutrik #NYS229
 $1.15  $1.15
 0602A Jack, 1/4 in. Stereo Neutrik #NYS230
 $1.25  $1.25  


 2208 Diode 1N914
 $0.15  $0.45  


 0807 Black Fluted Silver Center knob, Small
 $0.65  $1.95

 0204 Switch - Taiwan X-Wing DPDT
 $3.75  $3.75


 1407 Capacitor, Electrolytic, Radial 50 V Non-Polarized
(1 mf.) $0.30  $0.60
 1409 Capacitor, Dipped Tantalum .22 mf. - 10 mf. 16 Volt
(.22 mf.) $0.40  $0.80
 1404 Capacitor, Electrolytic, Radial 16 V 1 mf. - 100 mf.
(10 mf.) $0.20  $0.20
 1404 Capacitor, Electrolytic, Radial 16 V 1 mf. - 100 mf.
(47 mf.) $0.20  $0.20
 1300 Capacitor Silver Mica 500V 10 pf. - 150 pf.
(47 pf.) $0.55  $0.55
 1102 Capacitor, Panasonic ECQ-B .056 mf. - .1 mf.
(.1 mf.) $0.30  $0.30
 1101 Capacitor, Panasonic ECQ-B 470 pf. - .047 mf.
(.047 mf.) $0.25  $0.25
 1101 Capacitor, Panasonic ECQ-B 470 pf. - .047 mf.
(.027 mf.) $0.25  $0.25  


 1001 Pot Alpha Single-Gang Audio Taper 24mm
(500K) $1.25  $1.25
 1000 Pot Alpha Single-Gang Linear Taper 24mm
(25K) $1.25  $1.25
 1000 Pot Alpha Single-Gang Linear Taper 24mm
(100K)  
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 09, 2006, 06:37:48 PM
Can I use this NP electrolytic caps where it is labeled 1uf (NP) in schematics?
The short answer to your question Izzy is yes.

Ceramics, polys, etc. are limited in that to make a capacitor with a large amount of capacitance would require a HUGE package.  Electrolytics are capable of delivering much higher capacitances in much smaller packages.  Generally speaking, it's very hard to find ceramic/poly/film/etc caps from 1uF up - and if you did, they'd be huge.  Hence the line in the faq that says use electros for anything over 1uF.  The majority of electrolytic caps are polarized.  There are, however, a specific type of Electros that are non-polarized - and they're called "non-polarized" (BIG surprise there...) or NP Electros.

I would recommend buying an NP Electrolytic cap for this.  That is what I used in mine.

cheers,
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 08:07:42 PM
Thanks that answer my question.  :)

One question;
Why is TS 808 ($170) so expensive compared to TS9 ($100)? Even though the only difference between them are changes in 2 resistor value.

That keeps me thinking which one should I go for?  :-\

Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 09, 2006, 08:15:21 PM
Why is TS 808 ($170) so expensive compared to TS9 ($100)?
Hype.  I'm not saying that the 808 is an OVERhyped pedal - that would be a judgement call - It's just that it's been hyped a LOT.  Supply & Demand + Hype = Big Price Tag.

Personally, I enjoy the flavor of the circuit, but my tastes are a bit odd/complicated/dependant on other things.  Right now it has a place on my pedalboard right after my Marshall Shredmaster.  The shredmaster is a very thick, crunchy distortion, and I use it for the heavy riffs.  I use the 808 basically like a treble boost/solo pedal, for when I want to stick out above the mix more, or just want a crispier, more trebly distorted tone.  With the Shredmaster on (I never use the TS808 alone, but that's just me), I can click on the 808 to get a higher overall tone out of my distortion chain.  The pedal itself has very little distortion and is probably 'best' used to drive a tube amp into tube distortion.

cheers!
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: fixr1984 on October 09, 2006, 08:24:06 PM
something else to consider when buying parts is to get more than what you
need.  Most of the things you are getting now can be used in other projects,
so rather than place another order in a few days/weeks you already would have a good amount of
the parts needed.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 08:24:45 PM
I am kinda person who uses 70-90% of the distortion available everytime. So what would be the best way to increase the drive of This Tube screamer?
Increasing drive pot value? or decreasing 51k resistor?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 09:05:48 PM
I just want to make sure that all the Vb are connected to the same point right? Which is 4.5 v given by the 2x 10k and .47uf caps right?

And what is that arrow inside that green box for? The one thats pointing Ca?(In the figure below)

http://img145.imageshack.us/img145/3295/creamerfk7.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 09, 2006, 10:51:16 PM
Anyone?
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 10, 2006, 02:05:37 AM
  The green box looks like it shows the tone control components, possibly for reference to some subtext about it [not seen in that pic].
  The little arrow I think you're referring to is the V+ symbol, coming off of pin 8 [V+ of the opamp].
  The drive...someone else can explain...something to do with the 4k7 R and 4.7uf  cap coming from Vb and going to the tonepot/-input of the second oa.
  But...often simply adding a gain stage or chaining another distortion [see 'Shredmaster' subcontext in above post] to attain more grind/harder clipping...
  I'd go look at the schematic again, but I just twice lost posts with more typing than seen here...
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 02:11:54 AM
Thanks petemore for your Info. I guess that arrow was V+ for the opamp.

I would erally appreciate if anyone can answer this real quick as I am going to order all the parts from small bear right now.

I was going to buy small Boss type knobs:
(http://www.smallbearelec.com/stores/sbe/catalog/BlFlSilCtr.jpg)

but looks like  they dont have screws unlike the MXR ones which has screws on their side for knobs.

So is it those boss knobs dont have screws or am I not seeing them.? I want to get a knob with screw so that it will stay tight with pot.



This one has screws, I have used them for MXr project.
(http://www.smallbearelec.com/stores/sbe/catalog/45KN013.jpg)


I hope this one has too.
(http://www.smallbearelec.com/stores/sbe/catalog/12_217B.jpg)


Please, I would really appreciate if anyone can ans this real quick.

Title: Re: Need help building Ibanez Tube screamer.
Post by: pyrop on October 10, 2006, 02:34:32 AM
Hi Izzy, you could always email or PM Steve and ask him. You can find his contact details on his profile page HERE (http://www.diystompboxes.com/smfforum/index.php?action=profile;u=128)
Can't help you otherwise though sorry.
 
pyrop ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 02:41:48 AM
Looking at this PIC, I thing they do have screws. Thank god.  ;D

(http://i1.ebayimg.com/05/i/07/1b/a0/92_1.JPG)
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 11:27:17 AM
Dont these opamps need to be powered? and grounded?

Its not mentioned in the picture, so I was just wondering?

http://img145.imageshack.us/img145/3295/creamerfk7.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 10, 2006, 02:37:25 PM
I am kinda person who uses 70-90% of the distortion available everytime. So what would be the best way to increase the drive of This Tube screamer?
I started a thread on this topic not too long ago.  There are several very insightful posts that provide really good ideas for getting more distortion from a TS.  Here it is: http://www.diystompboxes.com/smfforum/index.php?topic=50019.0 (http://www.diystompboxes.com/smfforum/index.php?topic=50019.0)

But...often simply adding a gain stage or chaining another distortion [see 'Shredmaster' subcontext in above post] to attain more grind/harder clipping...
This is also true - this is pretty much how I use my TS to my liking - I just put it after another distortion pedal.  I get the tone and "flavor" of the TS, but all the crunch of the shredmaster.

So is it those boss knobs dont have screws or am I not seeing them.? I want to get a knob with screw so that it will stay tight with pot.
Those "Boss style" knobs from Small Bear DO have set screws.  I have a few of them at home...

cheers,
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 10, 2006, 03:07:01 PM
Dont these opamps need to be powered? and grounded?
In that image, you will see two triangles refering to the opamp... BOTH of these triangles are the SAME chip - just different pins of it.  Industry standard opamps (like this one), have pin 4 connected to ground, and pin 8 goes to +V.  The diagram listed actually does show that, but pin 8 is on one of the triangles, while pin 4 is on the other - again, they are the SAME chip... This chip, as many opamps, is a DUAL opamp, in that there are actually two opamp circuits inside.  Hence, we can illustrate it as two triangles.

Hope this helps - if you already knew this, i didn't mean to insult you  8)

cheers,
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 05:39:24 PM
Thanks A heap.!
I seriously didnt know that they were actually same opamp. Infact I just bought 2 opamps for this projects yesterday..haha..!
That's why I was wondering why one used 1,2,3,4 and other used 5,6,7,8. Know it makes sense!

haha Thanks once again!!! ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 10, 2006, 07:35:38 PM
Infact I just bought 2 opamps
  What kind?
 
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 10, 2006, 07:58:19 PM
pete asks a good question.  Not all opamp ICs are dual.  some have only one, some have 4... In the case of the TL07x series, a TL071 has 1 opamp, a TL072 has 2 a TL074 has 4 - there are many different opamps out there - check their datasheets for how many amps are onboard

cheers
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 08:02:02 PM
Infact I just bought 2 opamps
  What kind?
 

I bought 2 x JRC4558.

Since I have one extra now. I think I can replace my MXR's LM741CN with this one for more quiter sound. Am I right?
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 10, 2006, 08:11:35 PM
4558's are industry-stabdard dual opamps.  They are also known for having a smoother/quieter sound - I dont know the 741's, but you're in the right direction.  try it out, see what you think! :)

zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 08:27:35 PM
First I need to make sure before I try them out. I dont want to fry my MXR  ;D

Does anyone knows if I can replace LM741CN with JRC4885?  :-\
Title: Re: Need help building Ibanez Tube screamer.
Post by: burnt fingers on October 10, 2006, 09:14:42 PM
Izzy,
 
I can appreciate your need for information but you might try searching as many of your questions could be answered by previous treads, FAQ and other information readily available on this site as well as Geofex, AMZ, etc...

look at the data sheets for each op amp.  I think you will find the info you need there.
 
Scott
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 10, 2006, 10:00:27 PM
Yes sir, I did searched using "JRC4885" but I couldnt really find info realted with replaceing chips. Infact only 3 post showed up.
May be I am using the wrong keyword? :-\
Title: Re: Need help building Ibanez Tube screamer.
Post by: Eric H on October 10, 2006, 10:19:58 PM
First I need to make sure before I try them out. I dont want to fry my MXR  ;D

Does anyone knows if I can replace LM741CN with JRC4885?  :-\
The 741 is a single opamp, the 4558 is a dual, so the simple answer is no.

-Eric
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 11, 2006, 03:08:33 PM
Izzy:

one of the best tips I ever got on this forum was to find datasheets on google.  Just go to google.com and type "JRC4558 datasheet" or "4558 datasheet".  There are many free services out there with all of the major datasheets.  Also, if you go to mouser.com and find the product you're looking for, the datasheets are linked there as well..

have fun!
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 11, 2006, 10:25:37 PM
Thanks petemore..

I just used "DIY layout creator" to build schematic on stripboard that I bought from Aron. I was so pissed off because of the slowness of this software.  It was so damn slow, to add anything i had to wait 5 sec.!! Is it because I am using vista? Or is this software like this?
Is there any other good software for strip board?

Anyway one Main question:
I have heard people say - you should always solder resistor and other element closer to the board so that they dont act like antenna. Now  I wanted to know if exposing leads of resistor wide acts as anteena or not? Like the one I have made in strip board below? Or is it only the height matter?

Can anyone check this stripboard below if they can find any error?
Esp I am confused about potentiometer wiring??

http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 01:51:22 AM
If anybody could answer my question. I would be very thankful.
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 12, 2006, 02:07:56 AM
I have heard people say - you should always solder resistor and other element closer to the board so that they dont act like antenna. Now  I wanted to know if exposing leads of resistor wide acts as anteena or not? Like the one I have made in strip board below? Or is it only the height matter?
  Technically 'they say' quotes are true, having long leads open, even inside the shielded boxes can lead to noise issues. Everybody runs the signal path and other through wires to pots, sometimes longer wires, and any lengths of conductive surface carrying current can add to noise.
  I can't begin to calculate the lead length necessary to do what I suggested ratio to noise increase, but guess it to be undetectable in a TS [it's not super high gain], compared to the <1/4'' added 'antenna' on some resistor leads.
  But it is another variable, once soldered in, it's hard to change.
  It's good to consider how close you want those R's soldered to the board before doing so.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 02:34:28 AM
hmmm Thanks once again.

Looks like I will have to re arrange this whole thing  :'(

http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 12:30:27 PM
So do you think I will have to reararnge the whole thing so that the leads get less exposed to air, which will help to reduce noise? Or is this good enough?

http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 12, 2006, 01:47:26 PM
So do you think I will have to reararnge the whole thing so that the leads get less exposed to air, which will help to reduce noise? Or is this good enough?

http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg

Your layout does have a lot of exposed leads, which could make it prone to excess noise, but I'd be more worried about the size of your layout.  As it is, I don't think it will fit even in a BB enclosure.  At least not comfortably.  If you're doing it on strip board anyway, I'd look for a layout in here:  http://www.guitartone.net/vero.htm

I believe there's one in the Torchy album for the tubescreamer.

Otherwise you're going to have to rearrange your layout to make it more compact.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 01:54:10 PM
Thanks for replying sir.

The stripboard might look kinda big but I guess its 2 x 3" board which I will try to fit in a box.

Yes sir,  I knew the Torhy's layout was available. But I didnt want to copy. As my sole purpose of building pedal was to learn.

I guess I will have to rearrange everything.

1>>>
Can anybody tell me how many lines do I have to leave inbetween for resistor to make perfect horizontal fit in a stripboard?
Is it 2? or 4?

2>>>
Does anybody knows what software did Torchy use for those stripboard layout?
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 12, 2006, 02:05:32 PM
I believe it's 2 holes in between leads to make a resistor lay flat.  But it depends on the size of the resistor.  I'd say 2 holes for a 1/4 watt resistor.  As for the layout; he probably just drew his layout himself using a plain old drawing program.  There are templates in some of those albums.

2x3 might seem like it will fit ok, but space just seems to magically disappear when you start putting wires and switches and jacks and LEDs and DC jacks and batteries... you get where I'm going with this.  Smallest possible is usually the best way to go.
Title: Re: Need help building Ibanez Tube screamer.
Post by: zpyder on October 12, 2006, 02:19:25 PM
I'll confirm that "2-holes in between" works well for most 1/4 watt resistors.  I generally think of it as "4 holes across" but who really cares what I think.  There are definately some larger resistors that require 3-in-between/5-across.

chao
zpyder
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 02:21:37 PM
Thanks a lot. Now I guess I can rebuild the layout again safely .  ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 12, 2006, 03:02:11 PM
   I never paid a whole lot of attention to having resistors flat on the board [nearest possible to ground plane], and my pedals are all comparitively 'very quiet'.
  Layouts vary from as miniscule as possible to sort of spread out, certainly adding more lead length [antenna] cumulatively than raising resistor leads here and there ... whether this matters for noise much/at all, I'll let others sort out. But add the reason I typed it in the first place is because it's your choice, and I think the noise difference in either case would be indistinguishable to non-existant...compared to other noise sources, and simply because it is not recommended, I mentioned it. Sure makes trying this and that value out alot easier. Another way is to just use sockets, these also raise the component a little bit, I could be wrong, but I don't think it matters....has the chance of mattering some to more with super high gain circuits.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Torchy on October 12, 2006, 06:24:10 PM
So do you think I will have to reararnge the whole thing so that the leads get less exposed to air, which will help to reduce noise? Or is this good enough?

http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg

You'll more likely get oscillation than noise with that layout. Problem with med - high gain vero builds is whats being carried by the tracks underneath resistors and caps (and links) as well as lead length. The first couple TS layouts I did had noise and osc problems. That layout is probably generation 5 or 6.

I used MS Paint btw.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 12, 2006, 07:09:52 PM

I used MS Paint btw.

You mean Micro soft Paint brush ?? ?? ?? ?? ??

 :o :o :o :o :o :o :o :o :o :o :o :o :o

You must be kidding! ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 13, 2006, 09:00:33 AM
I just wanted to make sure about this gain thing. I wanted to add more gain/distortion to Tube screamer.

so, In this tube screamer if I want to increase the gain it can done by changing 4.7 k resistor to half. right?

And to compensate for the tone I guess I can double the cap value to get the tone I was getting when the resistor was 4.7k, Right?


So If I put 2.2k resistor in place of 4.7 k thenat full gain
Gain = 1+(500+50)/2.2  = 260 ,right?

high pass filter frequency with 4.7 k resistor:

f= 1/(2*pi*4700ohm*.000000047f) =  720 Hz




If I put 2.2 k resistor in place of 4.7 k
So now to find out capacitance value with 2.2k resister :

f= 1/(2*pi*2200ohm*Cap)

720 = 1/(2*pi*2200ohm*Cap)

Cap = 1/(2*pi*2200ohm*720)

Cap = 0.00000001 f = 0.01 uf

So that means I should replace cap with .01 uf if I change resistor to 2.2 for compensation for tone? Is that right?



http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg
Title: Re: Need help building Ibanez Tube screamer.
Post by: ubersam on October 13, 2006, 02:53:56 PM
...so, In this tube screamer if I want to increase the gain it can done by changing 4.7 k resistor to half. right?
Yes. In my last TS build, I went down to 1.5k, replaced the 51k with a 10k so that I will have less drive in the lower settings.

...And to compensate for the tone I guess I can double the cap value to get the tone I was getting when the resistor was 4.7k, Right?
Yes.

If I put 2.2 k resistor in place of 4.7 k
So now to find out capacitance value with 2.2k resister :

f= 1/(2*pi*2200ohm*Cap)

720 = 1/(2*pi*2200ohm*Cap)

Cap = 1/(2*pi*2200ohm*720)

Cap = 0.00000001 f = 0.01 uf

So that means I should replace cap with .01 uf if I change resistor to 2.2 for compensation for tone? Is that right?
Something went wrong with your calculation, you should have come up with 0.1 uf. A 0.01uf cap with a 2.2k resistor would set your corner freq. to 7.23KHz. Alternatively, a 0.1 uf cap and a 2.2k resistor will give you 723Hz.



http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg
[/quote]
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 13, 2006, 10:50:04 PM
Oh sorry My bad , that was 0.1 uf. haha

thanks for making it clear.

Is there anyway I could add midboost to the pedal with knob?


Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 14, 2006, 10:03:54 AM
any body?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Eric H on October 14, 2006, 10:22:57 AM
Oh sorry My bad , that was 0.1 uf. haha

thanks for making it clear.

Is there anyway I could add midboost to the pedal with knob?



-Izzy, how do you know you want a mid-boost, when you have already modded this circuit and haven't built it yet? My recommendation is to get it built and listen to it through your rig first.

-Eric
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 14, 2006, 10:27:33 AM
I know this pedal has enough mid boost.
But I just wanted to know how to add Midboost. With low pass filter and high pass filter we can control bass and treble but i wanted to know how do we control MId?  ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 14, 2006, 05:59:40 PM
anyone? :-\
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 14, 2006, 10:20:44 PM
Let me repeat the question   :-X


Is there anyway I could add midboost to the pedal with knob?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 15, 2006, 07:08:34 PM
wow No one?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 17, 2006, 11:12:23 AM
I just want to make sure whether the orientation of transistor is right or wrong on the stripboard layout that I made.


Stripboard layout:
http://img150.imageshack.us/img150/7219/tubescreamernb6.jpg


Schematics:
http://www.tonepad.com/getFile.asp?id=81
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 17, 2006, 11:56:40 AM
If you go here:

http://www.datasheetarchive.com/

you can lookup the datasheet for just about any electrical component you can find.  Once you find the datasheet, lookup the pinout of the transistor you're using and check it against the schematic.  Make sure each pin (drain, gate, source, or collector, emmiter and base) is connected to everything it's supposed to be, and that will tell you if your orientation is correct.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 18, 2006, 08:06:36 AM
Ignore my stupidity, but I couldnt find the orientation of the transistor on the site you mentioned above.
 
but looks like its the other way around.  ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 23, 2006, 10:02:19 PM
Finally I finished My Ibanez TS-9 / TS 808 (switchable) today!

It worked!

BUT why so less gain/distortion? IS orignal pedal like this?(I have never played TS9)
It was just like very subtle overdrive! Distortion wasnt even closer to MXR dist+.
Can anyone tell is thats what I am supposed to expect?


Then I tried adding another 4.7k resistor parallel to the 4.7 k resistor(to lower the resistance) which was going out from feedback loop. But the increment in gain was veryyyyy less, almost unnoticable. Itsnt that supposed to increase gain/distortion twice as much as before?


And one more thing,  I tried putting 100uf caps from +9ve to the ground to reduce 60hz. But instead that increased the hum slighly??

Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 23, 2006, 11:09:47 PM
Yes that's what a tube screamer sounds like.  It's a smooth low gain overdrive.  Think Stevie Ray Vaugn tone.  He used a TS808.  As far as the gain, try lots of different values of resistors; sometimes it takes a drastic change in value to produce a sublte change in output.
Title: Re: Need help building Ibanez Tube screamer.
Post by: GibsonGM on October 23, 2006, 11:34:04 PM
That's what I was talking about, Izzy...why I like the MXR so much ;o)  They really don't come much more distorted than the MXR - what makes pedals different tends to be the diodes, input/output caps and if you add a tone stack or possibly another gain stage to them!  I don't care for the Tube Screamers myself, but they have interesting parts you can use in other pedals (such as the clipping section as a gain boost).

Perhaps playing with the resistor values can increase gain for you?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 24, 2006, 12:16:58 AM
Hmm ok. I was intrested in making this pedal because steve vai used to use it quite a few times, sometimes substituting for DS-1. SO I thought there would be enough gain! ;D

I am still waiting for  toggle switch to arrive , once it arrives here, I will show you guys the picture! haha

In mean while I think I should experiment with resistors..hehe ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: GibsonGM on October 24, 2006, 09:26:52 AM
You can often get 10 pedals for the price of 1, lol...I think you can't beat the MXR for mod-ability...I can make that baby sound like a Big Muff, or a Super Metal Pedal, or Tony Iommi's dark sound.  Vai used so much processing in the studio it's hard to figure out just WHAT was going on there!  Octave/harmonizer units, etc  ;)   Probably used his OD stuff for cleaner passages, and went to something heavy for the whammy bar swoops.    It's all in the caps and tone stacks, my man!  Can't hurt to build things and have them if you want them later, tho...
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on October 24, 2006, 09:47:30 AM
  It's supposed to sound like...of course an "Old tube amp...arent' they all...
  It's not as hard clipping as many Fuzzes, certianly not as clipping as a DIST+ or diode to ground type clipper.
  'Mild' clipping boosting overdrive sound...
  A boosting circuit in front of the TS can increase input source voltage = hits the diode threshold sooner/harder = harder clipping sound.
  Real nice for 'intermediate' clipping and boost...not clean, not hyper-distortey, good for lots of 'stuff'.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 24, 2006, 09:58:47 AM
Thank you GibsonGM and Petemore, Helpfull as always!

I did made few changes, I added turbo mode  :D.
When turbo mode is on it will engagae 2 more 4148 diode shunt to ground before the volume pot , and it changed 4.7k resistor and .047 uf caps after the feedback loop to 2.2k and .01uf. It helped to add lil more gain and fuzz. Just a lil though hard to notice.

Anymore suggestion will be appreciated! ;)
Title: Re: Need help building Ibanez Tube screamer.
Post by: ubersam on October 24, 2006, 12:58:06 PM
Change the 2.2K to a 1K, and the .01uf to .33uf = more gain and bassier
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 30, 2006, 11:05:59 PM
Finally I finished my pedal today. But there is still some hum. noise? How t get rid of it?
.Its there even when I put my guitar volume knob to 0. But when I turn off my pedal its gone.I checked with pattery its still there.
 Any idea?





(http://img172.imageshack.us/img172/972/dsc00080jl4.jpg)
(http://img180.imageshack.us/img180/9199/dsc00075lt9.jpg)


Title: Re: Need help building Ibanez Tube screamer.
Post by: fixr1984 on October 30, 2006, 11:22:25 PM
Are all your wires still that long now that its installed in the box?
Sometimes having extra long wires will give you problems.
I usually install all the pots, jacks, etc first and then trim the wires down
so they are just long enough to reach and to give a little room if i need to remove that
part.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 30, 2006, 11:31:38 PM
Yes they are still that long.  They might look long but when when I tried to box it, it was kinda short  ;D
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 30, 2006, 11:54:27 PM
I used Audio probe and put guitar volume at 0. Then probed it from input. And it seems the small hum/noise comes after opamps output. JRC4885.
Could this noise be because of this so called "Noisy opamp" ?

HELP! :-\
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 31, 2006, 11:03:37 AM
From the picture it looks like your layout is still very big.  Lot's of exposed leads will create extra hum.  Also, make the wires from your input and output as short as possible.  They look to be about 6 or 8 inches long in the photo, that's too long.  If that doesn't solve the problem get some shielded wire and use that for your input and output.  The core is the lead, and the shield gets connected to the ground.  If you can't find shielded cable try twisting 2 wires together, using one as your lead the other connected to ground.  That might help a bit, but probably not much.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 11:57:32 AM
No the wires arent 6" - 8" even it might look like that in the picture. I guess  normally they are 5". And  can you please show me where are the exposed leads at? If you are talking about that resistor in the switch I have covered them with an insulating tape.

Do you think the if I covered all pots and switches  terminals with insulating wire will that help a bit?
 Its not a big hum/noise. Its little. But still I wanetd to get rid of it. I think its possible to make  a quiet pedal as commercial pedal isnt it?

Any help?
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 31, 2006, 12:09:34 PM
What I mean is, on the back side of your vero, not shown in the pic, if you have components stretched out with their leads exposed, it will create extra noise.  Like if a component is stretched across more than a few traces.  If you have several doing this, it will be worse.  For you input and output, you have to look at the total length; the length from the jack to the switch, then from the switch to the board.  Your pic looks to be about 4-5 inches from jack to switch, then another 4 or so to the board.  Making these as short as physically possible will make the pedal more quiet.  Shielding them may also help.  I don't know about the pots.  I built a TS, using as compact a layout as possible, with the shortest leads I could use, and it's dead-quiet.

Basically, smaller design=less noise.  Components act like antennae that pick up unwanted frequencies.  Insulating them with tape or rubber won't decrease the noise, but shielding them might.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 12:17:37 PM
Thanks sir. I appreciate your help. As far as I am concered I havent streched out leads on the other side, beside those caps which might be 2-3 mm above the board.
But what makes me suspious about the terminala at the pot is  the pedal is dead quite untill it reaches inputs of opamp and when i probe at the output then the hum/noise starts. The output of the opamp node also has drive pot connection. So I was guessing about that.

Can you give me some Idea how to shield? Does it has be to shield just with the input and output wire or for all the pots and switches?
And how do you make shortest wire possible? Even with this wire length I had hard time placing it inside box and reaching the switches and pot holes .
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 31, 2006, 01:12:40 PM
Well there's no noise until after the amplifier, because that's where the noise gets amplified  ;).  If you cant shorten any of your wires, you'll probably just have to live with it.  If you want to try and shield your input and output leads, get some shielded cable.  Like guitar cable only a lot smaller.  It has an inner-wire that you use just like you're using regular wire for your ins and outs, then an insulator, then it's surrounded by a bundle of wires, or sometimes a mesh, that will be connected to the ground, and then it's insulated again.  idealy you connect one side of the ground mesh to the jack ground and the other to te ground at your switch or circuit board or wherever.  It's essentially the same as it is now only the ground going to your jack is surrounding the lead, just like in a guitar cable.  And as I said before, you can also try just twisting these wires around each other.  That will sometimes decrease the noise, but it's not as effective.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 01:47:33 PM
http://www.smallbearelec.com/Detail.bok?no=86

is this the one?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 01:50:38 PM
and looks like just now I fried my IC JRC4885. I dont know how. theer is this  hmmmmmmmmmm sound in opamps output 1 and at 5 other legs are working. I dont know what's wrong.haha

This stupid adapter has been giving me 14v even at 9v!
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 31, 2006, 02:18:34 PM
Yeah that's the stuff.  Although your voltage issue might be part of the problem too.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 02:22:23 PM
Thanks Once again Sir. So do you think My IC is fried?
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on October 31, 2006, 02:54:22 PM
I don't know.  If you do a search for the datasheet it will tell you how much voltage it can handle. 
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 03:35:58 PM
Ican handle 18 V.
It was working fine till yesterday. Today mourning when I tried to use it. Then  it doesnot work Properly. ???
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 04:50:14 PM
Does anyone know what could be the problem? Is it the opamp?
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on October 31, 2006, 09:30:42 PM
can anyone rescue me? :-X
Title: Re: Need help building Ibanez Tube screamer.
Post by: petemoore on November 01, 2006, 09:03:25 AM
  Sounds like something changed, perhaps the voltage on the pins changed also. I would re-take the voltage measurements.
  If the chips shows good bias it's probably good, if you've socketted it you can swap to use process of elimination opamp test [the only way I know to test an OA is to set it up in a circuit that biases it...a known working circuit, and see how it compares to a known working OA...sound and bias wise].
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 01, 2006, 09:12:27 AM
Thanks Petemore, I appreciate your hjelp.
Can you please explain lil more in detail? I am kinda new to those  those stuff.
Thanks iN advance
Title: Re: Need help building Ibanez Tube screamer.
Post by: GibsonGM on November 01, 2006, 10:08:02 AM
Hi Izzy,

The standard 'debugging method' here (In the FAQ) is to measure all your pin voltages and post them.  The 4558 can handle +/-18v, IIRC, but that is measured from a correctly biased source.   What he means is to check voltages, and if nothing jumps out at you, take the chip and put it in another circuit that you KNOW works with a 4558.  That could be something simple from the data sheet that you know works with a new IC.   That's about the only way to test an IC for failure.  No easy ways around it. 

Seems like you already have a suspect, your adapter!   I make my circuits to work on battery only at first, no stomp switch, and if I want an adapter/switches  I'll add one after I know it works...there's an engineering maxim called "KISS"...Keep It Simple Stupid!  ;)   Learn about Zener diodes if you are worried about that 14v...a 9.1V zener could help you regulate that.  Post voltages...

Good luck,

Mike
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 01, 2006, 09:43:32 PM
Hey my rescue man is here!! hurray!   ;D

Ok I did as you said. But before that my prime suspect. I guess its the adapter because when I measure the voltage its gives me 17.xx- 18.xx volt at any place where I set 3v-12 v in my universal adapter. It was giving me 14.xx V yesterday. So I guess that 18 V either destroyed my Opamp or my capacitor!
How do we find out whether the caps are working or not?

Beside that here are what I emasured with  9.08 V battery


1.What does it do, not do, and sound like:
It was working fine  the day when I made it. even though there was small amount of noise/hum. ( I assume my adapter was running at 14 v at that day.) By the end of the day it burnt my 2 LEDs.
The next day I guess adapter suddenly changed to 18.xx volt for no reason. Now it sounds like  quaaaaaaaaaaaaaaaaaa and changes pitch if I touch it. It even makes noise when I turn off now. It was workign fine when I turned off till yesterday.

2.Name of the circuit = Ibanez TS-9/808
3.Source of the circuit (URL of schematic or project) = Tonepad
4.Any modifications to the circuit? Y


6.Positive ground to negative ground conversion? Neg ground (I guess thats what is it)

7.Turn your meter on, set it to the 10V or 20V scale. Remove the battery from the battery clip. Probe the battery terminals with the meter leads before putting it in the clip. What is the out of circuit battery voltage? => 9.08V

Now insert the battery into the clip. If your effect is wired so that a plug must be in the input or output jack to turn the battery power on, insert one end of a cord into that jack. Connect the negative/black meter lead to signal ground by clipping the negative/black lead to the outer sleeve of the input or output jack, whichever does not have a plug in it. With the negative lead on signal ground, measure the following:
Voltage at the circuit board end of the red battery lead = 9.09
Voltage at the circuit board end of the black battery lead = 0



Q1 (2N3904)
C =9
B =4.5
E =4.13

Q2  (2N3904)
C=9
B=4.27
E=3.7

IC1 (JRC4885)
P1 = 8.45
P2 = 7.6
P3 = 6.64
p4 = 0
p5 = 9.17
p6 = 8.5
p7 = 8.5
p8 = 8.25
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 01, 2006, 11:26:36 PM
I just tried to play it wthout the IC then it sounds fine when it is bypassed.

And when I plug in the opamp, even when it is by passed it gives. quiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii sound. When I touch the input jack of guitar the pitch goes higher.

So I am suspecting its the opamp.
But Please help me here with your experience!
Thanks in Advance.
Title: Re: Need help building Ibanez Tube screamer.
Post by: GibsonGM on November 01, 2006, 11:45:10 PM
I'd say the OA is porked, Izzy  ;)  It happens; I keep spares for this!  The quiiiiii is self-oscillation.

Read this:  http://www.repairfaq.org/sam/captest.htm#cttes (http://www.repairfaq.org/sam/captest.htm#cttes)

I'd try bridging the electrolytics 1 at a time to see if it makes the oscillation go away before doing anything else.  It's probably the IC that got popped by the voltage, tho.  An audio probe after the signal in (with signal applied, lol) will tell you if the caps in the signal path are dead.  No audio = dead.  This might actually be the easiest way to go.

What you might try doing after that is, with just the battery - no adapter, measure the voltages at the socket pins with NO IC in place.   You should get battery V on pin 8, 0 on pin 4.  About 0 on the other pins, I think (no schematic right here).  If this is the case, go ahead & put a new 4558 in.

That should get you going!
Good luck!
Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 01, 2006, 11:50:38 PM


I'd try bridging the electrolytics 1 at a time to see if it makes the oscillation go away before doing anything else.  It's probably the IC that got popped by the voltage, tho.  An audio probe after the signal in (with signal applied, lol) will tell you if the caps in the signal path are dead.  No audio = dead.  This might actually be the easiest way to go.

Did you mean shorting the caps?

Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 02, 2006, 01:52:09 AM
Ok Gibson GM , I did as you said.

I checked the voltage at the IC sockets with the IC removed.

Then

P1 - 4.5 V
P2 - 4.3 V
P3 - 4.5 V
P4 - 0 V
P5 - 9 V
P6 - 4.5 V
P7 - 4.5 V
P8 - 4.5 V

Schematic:
http://img365.imageshack.us/img365/6855/creamerwg0.jpg



Then I tried to check with audio probe, the quiiiiiiiiiiiiiiiiiiiiiiiiiiiii sound comes from everywhere in the circuit.

Then I removed IC and checked  the signal from the input. The signal goes fine till opamp. after that there is no connection (Since opamp removed)

So probably opamp?


Title: Re: Need help building Ibanez Tube screamer.
Post by: Jay Doyle on November 02, 2006, 10:30:27 AM
Sounds like it Izzy. I'd toss that adapter out, by the way.  :)

Use a battery, replace the opamp with any dual you have lying around and see if that works. With the voltages you have without an opamp in there, it looks good.

I think a new opamp will do the trick...
Title: Re: Need help building Ibanez Tube screamer.
Post by: MikeH on November 02, 2006, 10:39:49 AM
This is also why you might have had trouble getting more gain out of the tubescreamer.  At higher voltages, it would have greater headroom and distort less.  Anyone want to back me up on that?  I'm no expert on Tubescreamers at higher voltages, but that sounds right to me.
Title: Re: Need help building Ibanez Tube screamer.
Post by: Jay Doyle on November 02, 2006, 10:49:23 AM
This is also why you might have had trouble getting more gain out of the tubescreamer.  At higher voltages, it would have greater headroom and distort less.  Anyone want to back me up on that?  I'm no expert on Tubescreamers at higher voltages, but that sounds right to me.
Sorry, but I can't back you up on that.  ;)

With the diodes in the feedback loop, the voltage swing is limited to 1.2V peak to peak so whether at 9V or 18V the distortion/gain will be dependant on the size of the drive pot. For overdriving regular amplifier stages you are correct, but diode clippers change the game.

BUT, the tone control section will sound more 'open', to my ears at least. And you will have less of a chance of distorting the highs in that part of the opamp. I know that in EQs that use gyrators and caps to form EQ bands, a higher voltage tends to sound more 'open' as well.

Title: Re: Need help building Ibanez Tube screamer.
Post by: Izzy on November 02, 2006, 11:48:54 AM
Thanks you. I again Aprreciate your help.

Yes I will surely toss that adapter out. ;D IF i had any dual opamp around I would try it but right now I dont have any . I will have to wait till my order gets here from small bear.

Since you said high voltage will affect the tone. Probably that explain why I was getting sudden change in tone at higher level.Till 80% of tone control it moved smoothy and after 80 % it suddenlt used to change to high trebly noisy sound. Probably  because of high voltage?