Warden compressor Vero build help

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What's up guys? I'm new to pedal building and I have built a few Vero ODs and distortions with success I recently built a eqd the warden on Vero and I'm not getting signal through. This is a step up for me being a 6 knpb optical compressor. So I have questions about the vactrol (I made my own) and how it should react with signal and without. Should it be dimly lit even without guitar signal coming through? Also, I'm getting power to my ICs and Transistors but the voltages seem odd to me. And I'm getting voltages on E and C but not the base on both 5089. the substitution I made was a tl072 for the 2134 Here is a schematic and layout I built from. Here are my voltages. Thanks in advance.

IC1 (TL072)
1, 16.9
2, 6.59
3, 0.35
4, 0.03
5, 16.9
6, 6.93
7, 6.93
8, 6.8

IC2 (MAX1044)
1, 9.10
2, 4.51
3, 0.10
4, 0.60
6, 9.10
7, 3 53
8, 0.16

Q1 (MPSA18)
C 11.25
B 3.35
E 5.68

Q2 & 3 (5089) identical voltages
E 5.89
B 0.0
C 14.05

[bowanderror]

Your TL072 voltages look a bit wonky. Pin 4 is 0V like expected, but Pin 8 should be 18V, and Pin 1 should defo not be 17V.

As Q2 & Q3 are part of the side chain rectifier, you probably won't see voltage on their bases unless you're strumming pretty hard. The base of Q1 should be a bit higher as it's referenced to Vref (probably ~9V).

I'd suggest looking for short circuits or solder bridges around the power section, particularly the 2x 47k resistors that make up the Vref voltage divider. You can run a razor in between trace rows to ensure there is no bridging. If you want to take some photos of the top and bottom of the board, that might help us find any issues.

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I had the 10k resistor coming from the emitter of mpsa18 going up one hole too far, i moved it to the correct hole and got 16.5 volts on pin 8 but I'm still not getting signal. Here's some pics of the board, I knew I was forgetting something.  🙃   thanks for the help man. It's much appreciated.

[bowanderror]

Looks pretty good, so it's probably just a component in the wrong hole or a hard-to-spot short circuit somewhere.

I think the wires for your Release pot (green ones on the right side) might be in the wrong holes. Release 1 should connect to the 4.7k resistor, and Release 2 & 3 to the LED (-).

It's also worth taking a razor or drill bit to the cuts on the solder side as even a small amount of copper leftover will cause a short circuit.

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Ok will do. Thanks for the help. Like I said I'm fairly new to it and, not that I am great at reading schematics or understanding voltages but I k ew by the references on the schematic that something was amiss and with the 0v on the bases of the 5089 really threw me off so thanks for clearing that up for me. I will definitely recut those traces I noticed they were a little closer than usual on this pieces of strip board like the holes weren't centered on the traces so that's what im assuming It is. And just so I know for future reference the orientation of the LED on the layout the side with the stripe is the negative correct?? And the LED should be dimly lit as long as there's power to the circuit??

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Oh and good caught on the release. You were right.  😉

[duck_arse]

the mpsa transistor should have 2/3 V+ at collector and 1/3 V+ at emitter, and the base MUST be the emitter volts plus about 0V6 for anything to work right. the bases of the 2N5088's should be at 0V until you strum some input. 0V means those transistors are off, so the led//release can't see ground, so no current can flow, so the led should be off.

what are your voltages now you've amended the release pot wires?

[antonis]

 

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Ok so I recut my traces, reflow some solder fix the release wires and my voltages are
1044
1, 9.04
2,4.48
3, 0.03
4, 0.08
5, 0.18
6, 3.53
7, 2.34
8, 9.04

Tl072
1, 16.91
2, 6.42 (decreaes and increases depending on the ldr **I'm assuming**
3, 0.35
4, 0
5, 6.8
6, 6.9
7, 9.6
8 16.9

Mpsa18
C 11.3
B3.3
E 5.68

5089 (identical readings)
E 5.89
B 0
C 14.3

Sorry for delayed response I have a 6 month old son and he's not too into pedal building YET  😁

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I keep going over the schematic and layout and it seems like my voltages are correct except on the mpsa18 if it's supposed to be .6v higher than the collector then it's way off. It should be around 12v with my collector being  11.3v. So my question should be the voltages of the 1uf cap coming from pin 1 of the Tl072 ?? I see the 9v ref coming from the 1m resistor into the base of mpsa18. Also the 18v ref from the 10k resistor into the collector of mpsa18 so it seems my collector voltage is right and base should be around 11.9 -12v?

[antonis]

11.3V & 5.68V are quite OK for a 18V phase splitter, taking into account your DMM impedance..
BUT
you can't obtain those voltages with a 3.3V Base voltage..

On the other hand, a DMM of 1M impedance could dominate 1M bias resistor down to half, hence 3.3V taken measurement could actually be double (6.6V) which is ideal..!!

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I realized I misread that message. .6v more than emmitter, not collector. 😳

[snk]

Hello
If you're new to pedal building, the Warden is quite a big project, with several (error-prone) things to consider (I've been that route, and i'm not yet so skilled to give any lesson to anyone, so take my advice as you will ) : It's a 6 knobs pedal using a vactrol, so it involves both more cuts & wiring AND messing around with DIY vactrols.
I tried to build the Warden 2 years ago, and it didn't work. I scratched my head, I couldn't figure out why it wasn't working.
Then, I tried to mess around with simpler opto compressor... which ended sounding better than The Warden

My suggestion, if you don't have a big experience with building pedals :
1- start with a simpler design ( a two knobs pedals without any vactrol). Make it work, then tweak it to your tastes and see how each changes affect the overal sound and behaviour;
2- Then try a more complex design (like the Emma Transmorgrifier, or the Engineer Thumb, which are both 5 knobs design, but do not require a vactrol);
3- Then only, try to mess around with vactrols, which can be quite tricky to use : with one pedal, it will work at first try, and with another, it won't... It can be a compressor, a tremolo, a phaser, a vibe... The lightspeed compressor is amazing, so is the Baja Opto Limiter or Demeter compulator or Diamond comp. These pedals have few knobs, and are "built around" the vactrol, so you can focus on getting the led/ldr right... and the result is very rewarding
4- Then, go back to The Warden. THe benefits will be : 1- you will have got more experience in building (and debugging!) pedals, 2- you will have more experience with vactrols (always socket your LDR and LED, so you can try various combos), 3- you will know the kind of compression you like, and tweak your pedal to taste. Imho, The Warden is a great pedal, but I realized that I was quite often using rather similar settings (so having 6 parameters exposed didn't help both the workflow and the sonic result, even if I enjoy it).

I hope these advices can be useful (well, at least thi sis what I did)!
CHeers

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Yeah I've built maybe 8 or 9 Vero builds. All dist. OD or fuzz. I knew it would be a fairly difficult build and that's why I chose it,  also because I love compressors and eqd. I feel like If I don't challenge myself I won't learn anything. I've learned a lot in just a few small builds and except for 2 they all fired right up and through a bit a troubleshooting and what turned about to be a couple amateur mistakes I was able to get those to work too. I guess what im getting at is I wanted to attempt something I wasn't "comfortable" with. I have to admit though there was a lot about this circuit I didn't understand but after reading and asking questions I understand a lot more about optical compression than when I started. So, even if I NEVER get it to work at least I can say I got something out of it and as always I appreciate the advice. Thanks man.

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I just cut my LED out of the heat shrink to see how it was reacting. This may be a dumb question but when I first hooked my test leads to the 9v and ground of my circuit the led turns on (dimly) and slowly fades until its off. Is this because of the charge in a cap??

[duck_arse]

further to what antonis said .......



you need to go over ALL your cuts and dress them. clean out the little convex slivers of copper, so there is no shorts. I say shorts because your pin 1 TL072 volts is the same as your pin 8 volts. follow those tracks around about, and there might be an uncut cut. clear them all, remeasure yer volts.

about that phase splitter. the base is pulled up to 9V by that resistor [I can't squint enuff at the dias], and the collector is tied up to the 18V supply. so you would be expecting nearer to 9V on the base of that transistor, so emitter at about 8V, and so 10V at the collector.

the two following transistors have their emitters pulled to ground with no signal, so they should be at 0V, especially so because their bases are pulled to 0V when no signal on them. all these measures depend on no shorts messing them about. keep at it.


also - pin 3 pin 5? of opamp is tied hard to 9V, so pins 7 and 6 will be at 9V, pin 3 is tied weakly to 9V - so pin 3 will read low due to meter loading, but pins 1 and 2 will follow pin 3, and read close to 9V. should.

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I recut all my cuts again this time with a drill bit and exacto knife. I have the LED reacting to signal and the pots, the weird thing is I'm not getting signal out and my base on my mpsa18 is only like 3 volts and goes into -v when I put a signal on it. The other thing is pins 1and 2 of my op amp are at like 1.41 volts and increase with signal, as the led gets brighter. Same with pin 3 except standing voltage is less than a v. Somewhere around .44v.  Thanks for taking the time to help man. I really do appreciate it. Progress is being made. 👍

[duck_arse]

is there a version of the circuit diagram that matches your dual opamp version, preferrably better res than in th OP that we might be shown?

can you do the IC voltages all around again, please? it might be a good time to power off, pull the opamp from its socket, then power on and test the voltages on the empty IC socket.

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No sorry those are the only schematic and layout I know of. I believe there is another schematic for "the delegate" compressor based on the warden but the picture seemed smaller and harder to read than the one I posted. I printed the schematic and it's readable but still blurry. Here are my voltages (ICs in)
TL072
1, 1.6
2, 1 3
3 0.4 (led reacts when I probe this pin)
4, 0
5, 7.11 (led reacts)
6, 7.11
7, 7.16
8, 17.52

Max1044
1,9 1
2,4.5
3, 0
4, 0
5, 0.17
6, 3.53
7, 2.38
8, 9.10

Mpsa18
C 12
B 3.5
E 5.5

5089 (identical)
E 0
B 0
C 14.99

ICs out
Tl072
1, 0
2,0
3, 0.17
4, 0
5, 3.5
6,0.23
7, 0.23
8, 8.8

Max1044
1, 9.0
2 8.2 (decresed slowly to 0)
3, 0
4, 0
5, 0
6 0
7, 0
8,9

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I just used an audio probe and all the components before pin 2 on the op amp are good. Once I get to pin 2 it's sounds splatty like a misbiased transistor. Then everything In the path after that is splatty. Everything worked up until the 2 5089 I couldn't get a signal from it. Idk if this helps.