Big Muff Tri Help

tomcor33 · June 27, 2007, 02:19:34 AM

This is a great forum. I have already built a Fuzz Face , Red Llama, both work great. I am working on a Big Muff Tri from Andrew Carrell's Perfboard layout. Has anyone else built from this layout? I have traced all connections 3 times carefully. Maybe there is a problem with this layout? Probably not but I just wanted to know if anyone else has built from this Layout? Been trying 3 days to get it working. I get low volume on the sound and the drive and tone is not right.

jlullo · June 27, 2007, 02:29:43 AM

tom,
take a look at the sticky "what to do when it doesn't work"....

if you post your voltage readings here, we might be able to help you out!

jonathan

m_charles · June 27, 2007, 03:37:43 AM

I've built a few muffs, not from that layout.

you need to a/b with a regular schem, even if you're still learning to read them. That will solve your problem quick!

1. check grounding, make sure everything has a ground that needs it.
2. make sure your trannies are faced the right way.
3. There is a tri schem going around that shows 10k pots. If your layout shows 10k pots, its wrong. You need 100k.

all this and what jonathan said in his post...

good luck.

chuck

theehman · June 27, 2007, 11:59:52 AM

Make sure the trace from VOLUME 1 is connected to ground. That doesn't seem to be very plain in the layout. R23 should connect to the other side of C13.

tomcor33 · June 27, 2007, 11:19:41 PM

I am using 100K pots. The trannies are orientated correctly. All the grounds are correct. I did find that I did not have Vol 1 connected to ground. I also checked R23 to C18 they are connected. You were right. But now I have no sound at all coming out of output. My voltages are:
Q1- E .020 B .66 C 1.80
Q2 E 0 B 0 C 8.14
Q3 E 0 B 0 C .036
Q4 E 0 B 0 C 8.14

I am using 2N5088 's
I tried using 2n3904 's Just in case I blew a transistor.
I will keep rechecking my connections. It has to be somewhere. This is kind of a tough build on small prefboard. I have been reading schematics for years. I will try to trace voltages from schematic next.

boyersdad · June 28, 2007, 02:31:30 AM

If you're getting 0v to one transistor, that's where to start looking. Trace the voltage path back til you find out why there's no juice there.

ambulancevoice · June 28, 2007, 03:05:15 AM

did you solder the transistor to the board or did you use sockets?

tomcor33 · June 28, 2007, 03:47:13 AM

I used sockets for the Trannys. I just went through the regular schmatic carefully. The Perfboard layout I was has 3 or more errors.
I think I will start over again with a larger perfboard and use the Tonepad layout instead.
Thanks

m_charles · June 28, 2007, 04:21:19 AM

If you perf it, I highly reccommend using the Radio Shack (or other brand) perf with the copper trace around each hole. You'll end up with a more solid circuit, and it will be easier and neater.

Also, you said you're cool with reading schems. For my first Big Muff on perf I did my own "literal" layout, meaning I layed the parts out as much like the schematic (from GGG, but it wasn't a triangle) as possible. I used a big enclosure so I was able to do it this way. I'm very visual so it made it much easier for me. just a thought...

also purley opinion, I'd go with the 2n3904's.

keep us posted!

chuck

tomcor33 · July 04, 2007, 01:33:55 AM

Still need help..
I started all over again on a new perfboard and followed the layout of the schematic. I have checked all grounds, battery connections, jack connections, pot connections. I am not getting any sound at all. I am using 100K pots also. I also went through the schematic one point at a time. All my gounds are hooked together also.

Here are my voltages.
Battery 10.12
Q1 C- 5.56 B- .81 E- .19
Q2 C- 4.63 B- .68 E- .04
Q3 C- 4.44 B- .63 E- .02
Q4 C- 10.12 B- .002 E- .001

Any ideas?
Thanks for any help.

Beros · July 04, 2007, 03:49:14 AM

I've built it too and, like you, couldn't get it to work.

So if you find the errors and correct them, could you please post the corrections to Andrews layout here?

I've been probing mine, and it seems to work up to around the second trannie.. But then again I am still new to the whole probeing thing, and haven't had the patience/time/<insert lame excuse> to go through it properly.

tomcor33 · July 04, 2007, 04:08:32 AM

What I found in the Andrew Carrell Perfboard layout. Tone 1 and Tone 3 are reversed. Also R23 and C13 should be hooked in paralell with Collector and Emitter as per Tri schematic. I ended up starting all over from the original Tri schematic. The Carell perf layout is somewhat confusing. I suggest you go into the DIY Maker program and print out just the PCB layout for this version. Makes it easier to see hidden connections on PCB. Also all crossed bold lines should be connected. After finding the errors with R23 and C13 I tore my perfboard apart.

Beros · July 04, 2007, 08:30:36 PM

I found MarkM's version. It's slightly different though.
http://aronnelson.com/gallery/album76/BigMuff_TRI_LAYOUT_001

markm · July 05, 2007, 12:19:03 AM

I can verify that mine works.
I built it and I've had many PM's about it and it works fine.
You fellas are perfing this one?

Beros · July 05, 2007, 12:24:49 AM

Quote from: markm on July 05, 2007, 12:19:03 AM
I can verify that mine works.
I built it and I've had many PM's about it and it works fine.
You fellas are perfing this one?

I am. Just finished the board. Just some wiring left to do, then I'm all set... I hope my recycled components survived the transplantation... And man I'm getting tired of perfboard.
Althoug it seems simpler than going to the store to buy etchant, a drill, drill bits, etc..

markm · July 05, 2007, 12:56:26 AM

Once you get set up to etch, there's not much more than etch and build.....
Hey, debugging is easier!

tomcor33 · July 05, 2007, 01:50:02 AM

Mark,
I was going to use your layout it looked good I even traced the schematic with it. I decided just building like the schematic would be easier. Next time I will etch my own or buy a pre-made board. I did find 2 resistors I reversed on my new layout. I now get some sound, but low volume. The vol connections seem to be backwards, and the tone and sustain only have a small effect. I will get some more voltage rteadings again. Also I will build a signal probe to trace circuit. This is a learning experience. All though I have done electronics since I was a kid. I also use to own a VCR repair shop for 6 years.

I had a whole bunch of effects I sold before I had schematics.
Memory Man worked fine.
Distortion + Script
Guild Foxy Lady.
Univox Superfuzz
Heathkit Fuzz I built
EH Bad stone
Mutron III
Original Tube screamer
67 Telecaster in pieces but whole
Blue Box
Phase 90
Silvertone 1451 amp

markm · July 05, 2007, 12:52:47 PM

Quote from: tomcor33 on July 05, 2007, 01:50:02 AM
I had a whole bunch of effects I sold before I had schematics.
Memory Man worked fine.
Distortion + Script
Guild Foxy Lady.
Univox Superfuzz
Heathkit Fuzz I built
EH Bad stone
Mutron III
Original Tube screamer
67 Telecaster in pieces but whole
Blue Box
Phase 90
Silvertone 1451 amp

Wow, that's some real nice stuff.......I love Teles.

tomcor33 · July 25, 2007, 01:54:30 AM

Update:
I got the Big Muff Tri working now. I went through the schematic and layout again and found 2 errors. That did the trick. Next time I will just order a pre-made PCB. Sounds great! I am using 2N5088 trannys. Vintage Tri schematic. Now if I can just get the Arion SAD-1 working I bought on Ebay for $15 plus shipping. That is in another post.

tomcor33 · May 27, 2008, 03:44:24 AM

To get this working I used the Tonepad Schematic here.

http://www.tonepad.com/project.asp?id=3

News:

Big Muff Tri Help