Yet Another TS-808 Clone Question

Started by ZDHfx, March 22, 2011, 02:25:00 PM

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ZDHfx

Hey everyone, heres yet another tube screamer clone question along with other stupid ones, I'll try to keep it short.

- Finished clone from tonepad. 
- Compared to a real ts-808 from 70s im pretty sure. 
- Clone is way louder and has way more bass/mids which doesnt allow that delicious TS tone to come through, you know the one when the gain and tone is all the way up and it sounds like the cones on your speakers are made out of trashcans?  Obviously being overdriven too much. 
- I have to turn the volume on the clone to 5 to match the volume of the orignial on 10. 
- I made a probe and poked it to pin 7 on the ic and the volume/drive sounded normal, so im guessing its the buffers? I checked all the resistors and they seem to be all right, ive always tried diffrent trans, same as the schem and other ones.  My question is: what else could be wrong with the buffers besides wrong resistors, are there other components responsible for producing that crunchy crisp tone besides the obvious tone circuit and input/output caps. 

Other/Stupid question:

1)I kept poking around with my probe and figured id poke a little right after the 7 pin, so i poked the the 1uf(np) thats connected to it and I noticed that the volume went up a little bit(enough for me to clearly notice)  What could be doing that, I didnt think capacitors had the capability to amplify

2)Okay, the answer to this one might be me just being crazy but who knows, so the first time I poked pin 7 with the probe  the output level/drive sounded normal(not stupid loud like it was before)  but I still wasn't satisfied with the tone, it still sounded bassy.  So i stared at the circuit for a while and proded some things like the diodes and then poked pin 7 again and this time the crunchy trebly tone was there, so I'm trying to figure out if maybe I just wasnt hearing it and then something in my head clicked or if it was something to do with the diodes.  They seem to be soldered in well.

3)When I disconnect the 9V from the voltage divider and instead connect it to ground it gives it a more overdriven fuzz sound, I'm guessing that has something to do with biasing, and since I havent fully grasped biasing I was wondering if doing that is harmful to the circuit at all.
Thanks for your help, the first question is my main concern and the others are just things I'm curious about.  I'll post pics/sounds next time i need a break from debugging.  If you want voltages I can post those too.

slideman82

I haven't checked TP pcb, but I think it has buffers as the original. That great difference seems to be a different IC, JRC4558D sound pretty loud, with great mids. Take a look at the original TS's IC.

IMHO, it's just another OD, not sure why is the holly grail of OD... based on IC... just pick the one you like most! That's why a clone could sound better than a TA75558 TS.
Hey! Turk-&-J.D.! And J.D.!

ZDHfx

Oh yeah I forgot to mention that it isn't on PCB, I did it on perfboard.

ZDHfx

Quote from: slideman82 on March 22, 2011, 02:51:46 PM
I haven't checked TP pcb, but I think it has buffers as the original. That great difference seems to be a different IC, JRC4558D sound pretty loud, with great mids. Take a look at the original TS's IC.

IMHO, it's just another OD, not sure why is the holly grail of OD... based on IC... just pick the one you like most! That's why a clone could sound better than a TA75558 TS.

The buffers are not used for bypass if that's what you mean by original.  I tried 3 or 4 diffrent ics and from what I've read, ics have very little to do with the tone.  And it was the holy grale to me before I even heard all the hype and stigma that follows it, the first time I played through one not knowing what it was and expecting it to be just another crappy distortion pedal I instantly realized it's the tone that ive been searching for.

slideman82

Yeah, I can't say anything about the tone... sometimes I like it! But with a Strat better...

This pedal works really fine boosting an overdriven channel... or other OD... that's my experience! Still don't know why it sounds so loud compared to a factory one... check the wiring again!
Hey! Turk-&-J.D.! And J.D.!

flintstoned

Kinda sounds like you accidentally did the diode lift mod that people do to turn it into a boost pedal. It cranks up the volume and loses overdrive. I bet either pin 1 or two on the Ic (or socket) didn't solder well to your leads. This is really easy to miss on perf, those pins are so small. And would explain why when you probe, pushing on the chip, it sometimes makes contact.
I forgot what I was gonna say here.

twabelljr

QuoteKinda sounds like you accidentally did the diode lift mod that people do to turn it into a boost pedal. It cranks up the volume and loses overdrive. I bet either pin 1 or two on the Ic (or socket) didn't solder well to your leads. This is really easy to miss on perf, those pins are so small. And would explain why when you probe, pushing on the chip, it sometimes makes contact.


+1! Check the clipping stage between pins 1 & 2, esp. solder joints and diode arrangement.
http://www.geofex.com/Article_Folders/TStech/tsxtech2.gif
Shine On !!!

ZDHfx

Ahhhhhhhhh someone please shed some light on this, I've been debugging all week long and all ive managed to do is figure out how to make it louder,  I even etched and built pcb version to make sure it wasn't my wiring that was screwin it up.  I think this one is even louder, plugged in, i have to turn my amp down to the lowest possible setting for it to be bearable inside, the amp has to be so low that when its bypassed you cant hear the clean signal at all.  and turning the tone from 9 to 10 for some reason gives it an even bigger boost, I know on tubescreamers turning the tone all the up gives it a little bit more volume/drive but this is way beyond that its like turning the volume up 5 db.  I've tripple checked all the parts and they seem right, then again I got them all from mouser and theres a possibility something is not right but I doubt it because I've built a TS with parts from pedalparts and smallbear and they look almost identical. PLEASEEEEE help, all I want in my life is a sweet tubescreamer clone.

jkokura

I had a problem similar to this. The last resistor for the output needs to be a 100ohm Resistor. When I first built this circuit, I used a 100Kohm resistor, which led to a very, very quiet pedal. I replaced it with the right value, and instantly it was fixed.

I know you said you checked your resistors, but I thought it might help.

Jacob

ZDHfx

the 100ohm is fine, and I think you misread my post, it's too loud not too quiet.  I think I found a big clue, the tone control seems to controll the volume/drive of it, when it's turned all the way down it sounds good/good volume, but when its turned all the way it cranks it as if its a volume or drive knob.  It seems like when the tone is all the way down it functions like a normal ts but as soon as you start turning it from to 1 or 2 , something changes and the tone gets bassier and it becomes way more gainy, any info will be apritiated. I'll post more info in a minute

ZDHfx

ok so could a 22uf instead of a .22 on the rc network from the 2nd lug of the tone pot be responsible for the extra gain/mids

jkokura

Quote from: ZDHfx on March 26, 2011, 12:45:57 PM
the 100ohm is fine, and I think you misread my post, it's too loud not too quiet.  I think I found a big clue, the tone control seems to controll the volume/drive of it, when it's turned all the way down it sounds good/good volume, but when its turned all the way it cranks it as if its a volume or drive knob.  It seems like when the tone is all the way down it functions like a normal ts but as soon as you start turning it from to 1 or 2 , something changes and the tone gets bassier and it becomes way more gainy, any info will be apritiated. I'll post more info in a minute


Sorry, you're right I did misread, but I think my point was that simple part mistakes can lead to funky behaviour. My first instinct now, because of my experience, is to wonder if I've got a part wrong. I've built the project you're doing several times, and I've never had the problem you're having unfortunately. Without good pictures I can't spot anything for you, but I can only encourage you to very carefully inspect your soldering and your part values and orienctation.

Jacob

jkokura

Quote from: ZDHfx on March 26, 2011, 02:39:30 PM
ok so could a 22uf instead of a .22 on the rc network from the 2nd lug of the tone pot be responsible for the extra gain/mids

Yes, that's a very, very, very big difference in capacitor value. If you've got major part changes like that, who knows what could happen.

Jacob