Wampler Ecstasy Problem/Debug Help

rocket8810 · January 12, 2014, 10:56:55 PM

Hey guys, I built the Wampler Ecstasy and finally got some NJM4580's, I put it in turn it on and it works great, except 1 thing. The output is considerably low, so low that its just below unity with maxed out volume on the "open" setting, and significantly lower on the other two, which makes sense due to the clipping diodes for the other settings.

I have triple checked layout and wiring, as well as inspected for solder bridges. Anytime I've had an issue with with the an effect that I can't seem to troubleshoot everyone has been able to help point me in the right direction. Thankfully I haven't had too many that I can't figured out, and they are getting fewer and farther between as I keep building pedals. Any help would be greatly appreciated, and I want to say thanks in advanced.

Here's the layout I'm using

duck_arse · January 13, 2014, 09:42:58 AM

circuit, circuit, circuit. show us the circuit!

what is yr voltage at pins 3 and 5? all your pins, really.

rocket8810 · January 13, 2014, 10:13:45 PM

Sorry for not posting pictures of the circuit, my camera broke the other day, I now have to go get a new one. I'll check the voltages at pin 3 & 5 as soon as I get home and will post them ASAP.

rocket8810 · January 13, 2014, 11:08:22 PM

Voltage Readings:
Pin 1 - 4.77
Pin 2 - 4.77
Pin 3 - 4.54
Pin 4 - 0
Pin 5 - 4.77
Pin 6 - 4.77
Pin 7 - 4.77
Pin 8 - 9.46

Just a long shot, but I'm figuring there's an issue with voltage to pin 4, and that it shouldn't be 0V. Should it be 9.46 like Pin 8?

I checked to see continuity, and everything on the bottom row up to the 9V line, and I get continuity up to the 100uF electrolytic cap. Once I check the side of the cap that attaches to the 9V source I get nothing.

IvIark · January 14, 2014, 04:15:56 AM

Voltages look good to me. Pin 4 is ground and so should be 0V.
In the past when being asked about a problem build, I'd say in 90% of cases when an effect sounds good but the volume is too low, a bad solder joint somewhere is responsible. Try reflowing any joints which look suspect (including offboard) and see if it's something as simple as that.

bluebunny · January 14, 2014, 08:56:48 AM

Quote from: rocket8810 on January 13, 2014, 11:08:22 PM
Voltage Readings:
Pin 1 - 4.77
Pin 2 - 4.77
Pin 3 - 4.54
Pin 4 - 0
Pin 5 - 4.77
Pin 6 - 4.77
Pin 7 - 4.77
Pin 8 - 9.46

Is there continuity between pins 6 and 7? They share the same voltage and it would explain unity gain on the second op amp stage (and probable low gain overall - assuming stage two is intended as gain make-up).

Quote from: duck_arse on January 13, 2014, 09:42:58 AM
circuit, circuit, circuit. show us the circuit!

+1. And just as soon as you get hold of a camera, show us the build too (close up!).

rocket8810 · January 14, 2014, 06:57:05 PM

Will do. I'm waiting for it to come in the mail. I do have continuity between pin 6 & 7. I'm going to take a look at all the solder joints and see if anything looks suspect. Also, I'm not sure if it sounds good or not as i can only really hear it with volume and gain at max, but like I said its below unity gain. I'm even thinking that since it's a small board i might try rebuilding it and see if its something on this board I did wrong.

It's funny because I've run into a few problems, but not low volume like this, for me it's a head scratcher.

IvIark · January 14, 2014, 07:10:15 PM

Sorry I missed that bit, you have continuity between those pins? So if you test them with the resistance setting of your multimeter is is showing zero resistance between them?

If you are then you do have a serious fault with your build, you must have solder hanging over onto other rows or are in some other way creating multiple row bridges.

rocket8810 · January 14, 2014, 09:14:31 PM

Checked the see the amount of resistance between pin 6 & 7 and I got 46.8k resistance. But for shits and giggles I checked for continuity again using the sound setting, and guess what? I get not sound signifying that there's continuity. Something is very wrong with the board I made. I know there's nothing wrong with the layout, as Mark's are great and its been verified. I think the best thing for me to do is to redo the board and see what I did wrong.

rousejeremy · January 14, 2014, 11:09:12 PM

With veros, check all your trace cuts, links and run something sharp between the traces to make sure there are no bridges.
I built this vero a while ago and it sounds great with a TL072

duck_arse · January 15, 2014, 08:58:55 AM

much as I would like to see your photos, what I meant by circuit was the circuit diagram. there are those amoung us who simply refuse to read vero layouts.

check that link top right next the 47k.

rocket8810 · January 18, 2014, 01:29:26 PM

So I decided to rebuild this pedal, as I was certain I did something stupid, but the same exact thing happened, but it does have better output then the first board. Here power Voltage readings are as follows:
Pin 1 - 4.78
Pin 2 - 4.79
Pin 3 - 4.56
Pin 4 - 0
Pin 5 - 4.76
Pin 6 - 4.78
Pin 7 - 4.78
Pin 8 - 9.50

Also, I got my camera to work long enough to take some pictures. Note that the blue wires are for the bass control and input, green is gain, yellow is the switch and tone, white is volume/output, black is ground, and red is power. Please mind the messiness. It's been taken out so many times I have to straighten everything out again once I know its good to go.

It looks like there's a bridge in this picture on the right hand side between the 5&6 row, but its just the angle and light. I checked it again and there is no bridge there.

rocket8810 · January 21, 2014, 04:41:54 PM

Anyone? Bump

rousejeremy · January 21, 2014, 07:17:13 PM

To the right of the IC, you have a 470K resistor where there should be a 47K. Right between the two 100k resistors.

rousejeremy · January 21, 2014, 07:21:15 PM

AND, you have a 470K where there should be a 47k to the left of your IC. 470k is yellow violet black orange, 47k is yellow violet black red,

rocket8810 · January 22, 2014, 01:11:06 AM

Thanks Jermey. I just checked them with my meter and carefully looked at the bands, and they are 47k. Both are yellow, violet, black, red, brown. It the red and orange bands are hard to tell on the resistors from Tayda, so it might be hard to see on the pictures.

I just don't what could cause there to be such a low volume when the pedal is engaged. Not to mention whatever the issue is I had to do it 2x, since I built an entirely new board.

I built and audio probe figured that could help find the problem, but not sure how to really use it to debug this problem. Any pointers?

Why could this problem in general happen? Could it be a wiring issue between the pots? Cold solder joint? Or anyone else see something wrong with the board/wiring?

Thanks so far for the help.

rousejeremy · January 22, 2014, 03:12:02 PM

Are you sure that's a 1uF cap in there? It looks smaller than the .047 below it.

stallik · January 22, 2014, 03:43:07 PM

The IC looks as if it's in upside down

Pojo · January 22, 2014, 04:52:13 PM

Quote from: rousejeremy on January 22, 2014, 03:12:02 PM
Are you sure that's a 1uF cap in there? It looks smaller than the .047 below it.

Agreed, I bet it's a 1nF.

duck_arse · January 24, 2014, 09:23:11 AM

+1 on the 1nF. even tho I still haven't seen a circuit diagram, if that is the output cap, it would make a fair dent in the volume at 1nF.

the socket is mounted upside down according to its indent, but the ic is the correct facing way.

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Wampler Ecstasy Problem/Debug Help