Hey guys, I had no idea where to post this but I have a question some of you might be able to help me with. I had a purple Timmy but always wanted a Surf Green one, so I found one for a steal and snagged it. But when I played through it, the pedal was just totally different than the purple one. Much more bass, kinda smoother, way less gain on tap. I read that these have different chips in them so I popped both open and they both seem to have JRC4559 chips in them... am I missing something? Thanks in advance.
Does everything else seem to be the same? Board, layout, other components....
Maybe a board revision that changed a couple of components/values?
If everything looks the same then I'd have to guess it's all in component tolerances. Could be as much as 20% for some parts.
Building pedals one at a time, it's easy for me to test every component to make sure they're close to the specified value. Somewhat mass produced products though, probably not so much.
One may have been modded, or Paul could have been using different cap values in the bass cut circuit.
There are a few differences in terms of layout/values. The surf green one says 2012 on the PCB but the purple one doesn't say anything. Just very interesting to me, I might do a little comparison video just for kicks.
Here's a link to a discussion on your question. It's pretty informative and may provide your answer.
http://www.thegearpage.net/board/index.php?threads/timmy-version-question.1444785/
might also be the result of tolerances of caps. Electrolytic normally have ±20%, film caps ±10%. It's a long shot, but this could influence filters, but it shouldn't be too drastic.
Any gutshots?
They never lie, quite curious about that.
Quote from: GrindCustoms on August 09, 2016, 02:57:18 PM
Any gutshots?
(http://i.imgur.com/vv3H54l.jpg)(http://i.imgur.com/3BWiNB6.jpg)
There are minor cap differences, the second board has burn marks on it, I wonder what the pot values are or if they are different.
Quote from: jimilee on August 10, 2016, 03:25:05 PM
There are minor cap differences, the second board has burn marks on it, I wonder what the pot values are or if they are different.
It's weird, I sold the first one. I just didn't like the way it sounded. The purple one is my jam.
Quote from: jimilee on August 10, 2016, 03:25:05 PM
There are minor cap differences, the second board has burn marks on it, I wonder what the pot values are or if they are different.
I think that might be flux residue.
Well, I see the difference.... the wires are the wrong color! ;) ;D ;D ;D
Paul C logo missing....
This is like those "spot the difference" cartoon pictures. :)
well, as Jimmy said, there are some obvious differences in caps:
4n7 vs. 2n2
47n vs. 39n
Electro cap vs. 1uF film
also, the one on the top left corner is a different brand at least, no idea about the value. And then there's this orange box left of the IC that I can't identify. But one has at, the other doesn't. I guess that pretty much solves the mystery. Desolder and put in the values of your favorite one and you should be good to go.
I thought it could have some variance, but that is quite noticeable far as the tone stack goes imo. Never thought he would vary that much from one gen to the other, thanks for sharing.
Quote from: GrindCustoms on August 11, 2016, 01:48:06 AM
I thought it could have some variance, but that is quite noticeable far as the tone stack goes imo. Never thought he would vary that much from one gen to the other, thanks for sharing.
The brown cap is a 47pf to ground on the input. That was put in due to some guys getting radio. Small enough to not really effect the audible high end, but large enough to cut down on radio noise. The input cap was changed from 47nf to 39nf. That changes the low end roll off from -3db@6.3hz to -3dB@8hz which really is no change. That was done years ago when there was a shortage of 47nf for a few weeks from all my vendors. Since it made no difference in performance I just stuck with the 39nf which I used in another spot. The output stage had it's values changed from the stock 2x 3k3 w/4n7f setup to 2x 10k w/2n2f. This was done to get a little less loading on the 2nd stage to help the headroom a tiny bit with a weak battery. The 1k5 preset resistor in the treble control was changed to 1k to bring the brightest setting back to where it was with the 3k3 setup. You would have to squint your ears to really notice any of these changes. What can't be seen is the treble control was changed to linear to cut back on the dead spot between 7-10 with the audio taper. That one had a big effect on knob settings. I'm not sure, but it probably has the volume pot tweak which had the resistor soldered on the pot, and then it was added later to the board which came after the version shown. I never promoted those pot changes because they don't effect the sound - just smoother knob settings and I didn't want it to look like I was trying to resell a new version to people.
Quote from: paulc on August 22, 2016, 10:27:20 AM
Quote from: GrindCustoms on August 11, 2016, 01:48:06 AM
I thought it could have some variance, but that is quite noticeable far as the tone stack goes imo. Never thought he would vary that much from one gen to the other, thanks for sharing.
The brown cap is a 47pf to ground on the input. That was put in due to some guys getting radio. Small enough to not really effect the audible high end, but large enough to cut down on radio noise. The input cap was changed from 47nf to 39nf. That changes the low end roll off from -3db@6.3hz to -3dB@8hz which really is no change. That was done years ago when there was a shortage of 47nf for a few weeks from all my vendors. Since it made no difference in performance I just stuck with the 39nf which I used in another spot. The output stage had it's values changed from the stock 2x 3k3 w/4n7f setup to 2x 10k w/2n2f. This was done to get a little less loading on the 2nd stage to help the headroom a tiny bit with a weak battery. The 1k5 preset resistor in the treble control was changed to 1k to bring the brightest setting back to where it was with the 3k3 setup. You would have to squint your ears to really notice any of these changes. What can't be seen is the treble control was changed to linear to cut back on the dead spot between 7-10 with the audio taper. That one had a big effect on knob settings. I'm not sure, but it probably has the volume pot tweak which had the resistor soldered on the pot, and then it was added later to the board which came after the version shown. I never promoted those pot changes because they don't effect the sound - just smoother knob settings and I didn't want it to look like I was trying to resell a new version to people.
Really cool of you to weigh in man! Pot taper makes total sense here.
thanks for clarifying. I agree with leevibe, really cool to actually take your time to answer here.
Quote from: paulc on August 22, 2016, 10:27:20 AM
Quote from: GrindCustoms on August 11, 2016, 01:48:06 AM
I thought it could have some variance, but that is quite noticeable far as the tone stack goes imo. Never thought he would vary that much from one gen to the other, thanks for sharing.
The brown cap is a 47pf to ground on the input. That was put in due to some guys getting radio. Small enough to not really effect the audible high end, but large enough to cut down on radio noise. The input cap was changed from 47nf to 39nf. That changes the low end roll off from -3db@6.3hz to -3dB@8hz which really is no change. That was done years ago when there was a shortage of 47nf for a few weeks from all my vendors. Since it made no difference in performance I just stuck with the 39nf which I used in another spot. The output stage had it's values changed from the stock 2x 3k3 w/4n7f setup to 2x 10k w/2n2f. This was done to get a little less loading on the 2nd stage to help the headroom a tiny bit with a weak battery. The 1k5 preset resistor in the treble control was changed to 1k to bring the brightest setting back to where it was with the 3k3 setup. You would have to squint your ears to really notice any of these changes. What can't be seen is the treble control was changed to linear to cut back on the dead spot between 7-10 with the audio taper. That one had a big effect on knob settings. I'm not sure, but it probably has the volume pot tweak which had the resistor soldered on the pot, and then it was added later to the board which came after the version shown. I never promoted those pot changes because they don't effect the sound - just smoother knob settings and I didn't want it to look like I was trying to resell a new version to people.
Thanks for the input Paul, really like how you make evolve your product so it have a better performance, especially what you did at the output stage for that weak battery matter, that is OCD like i love it! Great great job! :D
Rej