Carl Martin Quattro

[DutchMF]

Had one of these in for some minor surgery (busted output jack) and thought I'd snap a few pictures. I know it has some pretty decent sounds, as it's owner is a friend of mine who's been playing in the same band as me for over 12 years. Didn't have much time to take any notes, as he was looking over my shoulder, hoping it could be fixed before our gig on saturday.....





Couple of observations:
-alpha board mounted pots, just like we use them.
-only DPDT switches, so probably no true bypass, as it does use LED's (or maybe some form of Millenium bypass scheme?)
-loads of unmarked IC's, and the ones that had a label where almost all ones I'd never heard of!

I think I can persuade my friend to let me spend some more time with this beast, so more info is soon to follow....

Paul

[jkokura]

That's Rad Paul. First up, Carl Martin stuff is awesome. It's not common, but it's super good quality. Boutique before Boutique was cool.

I wonder what the Delay is based on. It's got stereo out, so that's interesting. Uses a SA571 compander? So perhaps it's a dual PT2399 based design, with tap tempo too? That alone might be worth trying to get more details on.

My bet is that the DPDT switches utilize some sort of millenium bypass or perhaps a modified bypass of some sort. We have to remember that it's not until recently that our 3PDT switches have been as numerous, common and inexpensive. 5 years ago, most people got them from Smallbear for $8 when doing DIY.

Jacob

[dbharris]

Awesome, thanks for posting pics!  All the shielded cable runs have grounds on both ends, is this because the jacks are isolated?

-Dan

[madbean]

Man, I would love to see some more shots of the delay section. It's hard to see, but I did not notice any microcontroller on there.

[DutchMF]

I'll try to get my friend to drop it off at my place again after our gig saturday (first gig where the only non DIY pedals on my board are tuner and wah!!). My plan is to get the circuit board out of there (single sided btw) and take some better pics. The delay section is definitely the most interesting part, but the dual drive and tremolo sections are cool as well. Only thing missing for a gig is a chorus and a tuner!

Paul

[DutchMF]

Awesome, thanks for posting pics!  All the shielded cable runs have grounds on both ends, is this because the jacks are isolated?

-Dan

I'm sorry Dan, but I don't know! Had very little time with it, plus the owner watching over my shoulder..... Hope to get into it a bit deeper soon!

[electricstorm]

From what I can make out on the IC's (only four so far) they are:

SA571N : Compander IC

74HC563 : Octal D-Type Transparent Latch ; 3 State ; Inverting

A273D : 2x NF-Stereo Potentiometer (Vol & Bal)

THAT4301 : Analog Engine (Used in Compressor/Limiter circuits among others)

Couldn't make out the rest of the IC's. Let us know what the remaining IC numbers are when you get a chance.

Here's the link for the A273D IC:

http://www.datasheetarchive.com/A273D-datasheet.html

And a link to a diagram:

http://stoom.ru/component/option,com_sobi2/sobi2Task,sobi2Details/catid,0/sobi2Id,108/Itemid,161/

An equivalent to the A273D looks to be a TC730A. Pinouts may be slightly different.

[DutchMF]

Well, this generated a lot more interest than I thought.... I'll be sure to get my paws on this again and satisfy your curiosity!

@electricstorm: You've got some damn sharp eyes, man!

Paul

[electricstorm]

Thanks Paul!

I think I looked those pictures over for about 20 or 30 minutes and then did some quick research on the IC's I could make out (except the 74HC563). The numbers on some of the IC's I hadn't seen before and that peaked my interest a little bit. BTW, the A273D IC's datasheet is in Czech or German language I think so if anyone here can interpret those languages, maybe they can translate the datasheets. I tried some web translators but didn't work on PDF's and JPG's.

I'm just guessing that the echo section is either MN3XXX or PT2399 IC's. There were several full wave bridge rectifiers on there too (2W04) and the two large components in the middle of the board look to be transformers (biege and blue), could be wrong though. The IC above and to the left of C24, from the logo, appears to be an Exar IC but I can't quite make out the number. If I had to guess, probably looks to be an XR 2104CP. Anyway, thanks for the pictures, it gives me a chance to polish up on my sleuthing skills! LOL.

Jim

[Arjepsen]

Well, this generated a lot more interest than I thought.... I'll be sure to get my paws on this again and satisfy your curiosity!

@electricstorm: You've got some damn sharp eyes, man!

Paul

Soo... Did you ever get to take some more shots of your friends quattro? :-D