Tri-vibe doesn't sound right

[egasimus]

I built the Tri-Vibe over the last couple of days, based on John Lyons' layout at ROG.

First thing I noticed that was wrong, I connected a LFO indicator LED as shown in the schematic, and it glowed really faintly (although it did pulse along with the LFO).
When I plugged the circuit in and strummed some chords, the only thing I got was a tremolo-ish effect in all positions, one being louder than the other two. It turned out I had miswired the switch, so I fixed that. Still nothing.

I'll measure voltage as soon as the FX board and my DMM stop sharing the same battery, but meanwhile... does any of this sound familiar to you?

Samples:
http://myspacefilehosting.com/lnbca/untitled.ogg.html

[crane]

I finished my tri-vibe a few days ago - ROG layout works.
Some things come into my mind when I read your post
1)LED problem - the LED in the schematic is NOT a tempo indicator - it is used fot different purposes and it has to be very dim.
The actual tempo LED is not in the original schematic - scroll down the pdf with layout and read the notes.
2)Sound problem - two things to mention. First of all - I had some volume drop issues when using TL072 so I switched to NE5532 and it worked nicely. But it seems like you have a different problem.
Seems like one of the OTA stages is working and the other is not. Check all the parts around U4 - there are not so many of them. Pay special attention to two 10k resistors coming from LFO.

[egasimus]

The LED on the board doesn't light up at all. I meant the additional tempo indicator LED mentioned in the ROG article. It lights very faintly, while I've seen video demos of other people's builds where it's quite noticeable.

[lopsided]

I would worry about the LED indicator after you got the circuit to work right.
I have an open working tri-vibe right now on my table.
So after you can send your voltages I can compare  them to mine easily.

[egasimus]

Thanks, that'll help. Hopefully, I'll be able to measure stuff tonight and post 'em.

[egasimus]

Alright, here's what I got. Pins marked with a tilde (~) are varying, apparently because of the LFO.

LM13600:
 U4b
1:   1.26
2:   5.49
3:   4.79
4:   4.78
5:  ~5.3
6:   0
7:  ~5.3
8:   4.83
 U4a
9:   4.9
10: ~5.3
11:  9.04
12: ~5.3
13:  4.73
14:  4.72
15:  5.39
16:  1.24

TL072:
 U1a
1:   4.49
2:   4.49
3:   2.23 (loaded down by DMM?)
4:   0
 U1b
5:   4.48
6:   4.48
7:   4.48
8:   8.94

TL074:
 U2a
1:   4.46
2:   4.46
3:   4.24
4:   8.9
 U2b
5:  ~4.38
6:  ~4.38
7:  ~2.8
 U3b
8:  ~4.2
9:   4.4
10: ~4.4
11:  0
 U3a
12: ~4.4
13:  4.04
14: ~4

[lopsided]

Hello

I post votlages of my workin tri-vibe. Unfortunately they seem to differ only very slightly from yours and do not point out to a obvious mistake.
I am using slightly different chips, but this shouldn´t matter much. Also the vero layout I used had U2a and U2b swapped)
I am also using a 10V supply so my readings are a little higher

lm358 (in/out buffer) 1-8

5
5
2,52
0
5
5
5
10

LM13700 1-16:
1,3
5,9
5,2
5,2
~6,2
0
~6,2
5,4

5
~5,9
10
~5,9
5,2
5,2
5,9
1,3


tl074 1-14

U2b (out,-,+)
~4,3
~5
~5

10


U2a (+,-,out)
4,75
5
5

U3b
~5
5
5
0


U3a
~5
~4,53
~5

[egasimus]

That's what I feared

[crane]

Don't give up just yet. First of all - did you use a vero or pcb layout?
2) did you check my notes about tempo LED? so which one are you looking at - the real tempo led or the one that is in circuit for different reason? Help us to help you - check these things and give us some info.

[egasimus]

based on John Lyons' layout at ROG

PCB

I connected a LFO indicator LED as shown in the schematic... I meant the additional tempo indicator LED mentioned in the ROG article.

I removed the actual tempo LED early on, and haven't tried it since. The on-board LED also pulses along very faintly.

[crane]

As far as I remember tempo LED was not even on the pcb. Anyway - the LFO is working fine - that's the good news.
This layout is verified and should be working (and as I said - I even have built it myself).
You should check for wrong parts around OTA and the opamp that is not in the LFO .
Anohter thing - check for soldering bridges on the bottom side of the pcb.
Checked your sound sample again - a lot of cracking noises - does that come from your guitar/recording gear or from tri-vibe?

[egasimus]

It's mostly my cables, really. I'll check the other stuff, though.

[egasimus]

I found it - I had put a 100k resistor instead of a 10k in the bottom right corner, right next to the 220n cap. It does thump when the depth is cranked to the max, but that might be one of several things, and not necessarily the effect itself - I'm testing it through the Line In of my desktop PC's built-in sound card, with the DAW's track and master faders cranked to the max, while my wife watches 90s sitcoms on the same machine My guess is that it's the sitcoms.