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Re: Friedman BE-OD Pedal

Posted: 03 Jun 2017, 23:32
by pakrat
albru80 wrote:Thanks Pakrat for checking the values.
I think there are 2 slightly different schematics here: one from Bmxguitarsbmx and one from Destro.
I've used the second one for the vero layout but I'm not sure which one of the two was the right one.
If this is Alex from tagboardeffects I'd like to thank you and the others for all that you do over there. I learned how to do vero from your site and have built several of your layouts with success. Thanks again!
I have gone over both schemes and it looks like Destro's is nearly complete and correct. The only components I see missing are the 3 SMD caps (C22, C23, C24). All of which are 100nf and each one connects between pins 4 and 8 on each of the 3 ICs. Also, Destro's scheme has a few values missing or possibly incorrect:
C2: 47pf
C8 is 100nf instead of 10nf
C9: 47pf
C23: 100nf
C13 is 100pf instead of 10nf
R30 is 10R instead of 100R

Bmxguitarsbmx's scheme needs a little more work than Destro's to be complete but not much. I'm here if he needs me to verify anything. Thanks to both of those guys for their work on this.
I built the version you posted so if you make some changes I can test everything pretty easily to see where we're at before you post it if you want. We can also compare it to the original until it's just right. Anything you want me to check, just ask.

Re: Friedman BE-OD Pedal

Posted: 03 Jun 2017, 23:53
by pakrat
Fermusicman wrote:C25 is 100n? Looks smaller than c22,23,24. Not so important, is part of the power supply. but... :horsey:
I'm fairly certain it is 100nf, possibly in a smaller package? All 3 of those SMD caps measured between 108nf and 112nf and since the tolerances are unknown, I would suppose they are most likely 100nf or possibly 120nf. I don't have any problem with removing it to double check if needed.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 01:25
by Fermusicman
It makes sense, same value but at a lower voltage. Thank you for your great work.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 02:06
by pakrat
No problem at all. I get a lot from this forum, if I can help I'm glad to do it.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 04:35
by bmxguitarsbmx
albru80 wrote:Thanks Pakrat for checking the values.
I think there are 2 slightly different schematics here: one from Bmxguitarsbmx and one from Destro.
I've used the second one for the vero layout but I'm not sure which one of the two was the right one.
Don't use either. Whoever tagged this topic as [traced] was speed reading past the important parts.

Just trying to be clear here

Re: Friedman BE-OD Pedal [schematic v9]

Posted: 04 Jun 2017, 04:57
by bmxguitarsbmx
This is completely hypothetical. I added what I liked from destro's work and updated the part numbers and values. It's an unknown amount of guessory.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 08:22
by albru80
Thank you guys.
I think Tagboardeffects wouldn't exist without this website.
This is still the same layout based on Destro's schematic.
As Bmxguitarsbmx said it may not be correct but considering Pakrat has already built it, it would just be a quick way to test those values changes.
I've circled the components that need to be changed compared to the previous layout. Didn't add the 3 100n caps between Pins 8 & 4 and I'm not sure where R31 (1M) goes to:

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 12:56
by albru80
Hi Pakrat! I know it's a lot of asking but would you be able to check a few things?
Does R2 (470K) go to VBias or the R32-R34 junction? C23 goes to Vdd or ground? Any chance of checking the whole scheme between R14 and Treble 3?

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 14:45
by pakrat
albru80 wrote:Hi Pakrat! I know it's a lot of asking but would you be able to check a few things?
Does R2 (470K) go to VBias or the R32-R34 junction? C23 goes to Vdd or ground? Any chance of checking the whole scheme between R14 and Treble 3?
Hello Alex, it's not a lot to ask... I'll do whatever I can to help until it's done.
R2 (470k) does go to the R32-R34 junction as shown in Destro's scheme. C23 connects to GND or pin 4 (VCC-) and pin 8 of IC2 (VCC+). C22 is the same way for IC1, and C24 for IC3. I apologize to everyone that I'm not better at this.... :block:
R14 to Treble 3 appears correct on Destro's scheme.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 14:57
by pakrat
albru80 wrote: I'm not sure where R31 (1M) goes to:
R31 is 10k and goes to the indicator LED

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 15:00
by pakrat
One more thing, 1N4148 seems to be a good choice to substitute the BAV99's.

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 19:48
by bmxguitarsbmx
albru80 wrote:Thank you guys.
I think Tagboardeffects wouldn't exist without this website.
This is still the same layout based on Destro's schematic.
As Bmxguitarsbmx said it may not be correct but considering Pakrat has already built it, it would just be a quick way to test those values changes.
I've circled the components that need to be changed compared to the previous layout. Didn't add the 3 100n caps between Pins 8 & 4 and I'm not sure where R31 (1M) goes to:
Seems like a lot of wasted time. Why not use a breadboard?

Re: Friedman BE-OD Pedal

Posted: 04 Jun 2017, 22:08
by teddeeh
albru80 wrote:How did it sound before the changes?
It got to unity cranked, a nice sound, i cant compare to original sadly but all controls worked. I liked the schem so much at thay current level i just stuck a boost on the output to get it louder. 2 volumes with one being a master still gives nice dynamic changes. I know its not correct, im happy with my socketed one to keep testing levels and possibilities.

Re: Friedman BE-OD Pedal [schematic v10]

Posted: 06 Jun 2017, 10:08
by YellowBoy
Hi folks

I took the time to sim Destro's scheme (with corrected values) and it's mostly there but with a few problems.

C13 now doesn't make sense as a coupling cap as the value is so small so it must be in the feedback of IC2B (just like C9 and C12)
C8 probably goes to ground or vbias (like the Timmy)...although 100nF seems pretty big. I found lowering this cap tames the bass
R2. Seems strange to buffer a bias voltage...then not use it here? But it's been confirmed so.

With the C13 correction this now becomes a loud circuit. I've only simmed it on ltspice but the difference between this and the "original" positioning is dramatic, and lines up with what was said before about only being able to attain unity volume when cranked. All pots now have a noticeable affect that appears to match their names.

So I redrew Destro's schematic (only because pakrat said it was closest) and matched up the component values and numbering then made the corrections I mentioned above.

I've also included the Freq response of Destro's C13 position and my edited C13 and C8. All controls at noon (midway). Blue = 1V Input Green = Output.
I used the ideal opamp in ltspice and red LED's and 1N4148's so this comes with it's own caveats.

Hope this helps and apologies for adding yet another schematic to the mix. I thought it might help having all the new info in one place. If you need/want me to try anything just ask.
Reworked Destro Scheme [version 10]
Reworked Destro Scheme [version 10]
Ciaran

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 13:19
by Frank_NH
Thanks for this YellowBoy. Funny, but I too just finished an LTSpice simulation of this circuit and agree with your comments about C13 (should be in the feedback loop). That stage looks to add a small boost to the signal, and C13 just rolls off some high frequency content.

Regarding C8, yes that goes to ground/vbias, and I was thinking that R4 = 22k was probably meant to be 2.2k, which makes C8 = 100 nF sensible (corner frequency = 724 Hz).

I looked at the waveforms up to the tone control and they look very good (amp-like), but I was having trouble with the tone control stage. In my simulation, it looked like it was not being biased correctly, but I may have made a mistake someplace in LTSpice. I'll check my schematic relative to yours and see what I find. By the way, I haven't seen this type of tone control circuit before - does anyone know where is comes from? I was considering replacing the BE-OD tone controls with an active Baxandall/James tone stack at the end. In any case, I plan to build this up on my breadboard using some LF353N op amps I have lying around, and try out some mods for fun.

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 13:58
by pakrat
Thank you Ciaran, that did it! On the tagboardeffects layout I removed C13 (100pf) and tacked it on the solder side of the board to the lower lead of R15 (10k) and the other end to pin 8 of the TL074. Then ran a jumper from Presence 3 to pin 8 of the TL074 and it is working! And I know it was already confirmed but, C8 definitely goes to ground and the circuit works without the 3 decoupling caps for the ICs (C22, C23, C24).
Great job!

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 14:04
by Frank_NH
Thanks pakrat. How are the tone controls? Good response across their sweeps? I'm going to check this out in LTSpice tonight, but if your build is working, that's great.

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 14:33
by bmxguitarsbmx
Yellowboy: try flipping the order of the presence control and the last clipping section. It doesn't make sense to me to have those controls interactive. (check my last posted scheme).

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 14:37
by pakrat
Frank_NH wrote:Thanks pakrat. How are the tone controls? Good response across their sweeps? I'm going to check this out in LTSpice tonight, but if your build is working, that's great.
The tone controls seem to work as the original but I'll A/B it after work today to see. Stupid real life..... :roll:

Re: Friedman BE-OD Pedal

Posted: 06 Jun 2017, 15:06
by YellowBoy
bmxguitarsbmx wrote:Yellowboy: try flipping the order of the presence control and the last clipping section. It doesn't make sense to me to have those controls interactive. (check my last posted scheme).
You may well be right bmx. Kinda like the MI Audio Crunch Box. I don't see much of a difference at the minute but I'll have a closer look tonight after work.

pakrat. Glad to hear you got it going! Let us know how close it compares to your original when you get a chance.

Cheers

Ciaran

EDIT: I'll update the schematic tonight as well and sort out the pot lug numbers