Need help building Ibanez Tube screamer.

[petemoore]

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.

[Izzy]

hmmm Thanks once again.

Looks like I will have to re arrange this whole thing 

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

[Izzy]

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

[MikeH]

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.

[Izzy]

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?

[MikeH]

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.

[zpyder]

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

[Izzy]

Thanks a lot. Now I guess I can rebuild the layout again safely . 

[petemoore]

   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.

[Torchy]

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.

[Izzy]

I used MS Paint btw.

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



You must be kidding!

[Izzy]

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

[ubersam]

...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]

[Izzy]

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]

any body?

[Eric H]

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

[Izzy]

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? 

[Izzy]

anyone?

[Izzy]

Let me repeat the question   


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

[Izzy]

wow No one?