Amptweaker - Tight Metal [traced]

[modman]

I can't believe this has not been dissected, yet?! Not even any goop on the damn thing! Anyway, I found these on the net and wondered if anybody else has one of these or if anybody has traced it, yet?

https://www.youtube.com/watch?v=Gp7EnYEQNIM

[coldcraft]

i had a tight rock for a while. nice set of features, but too bright for my tele.

[J0K3RX]

I would be happy with tight rock, tight drive, tight boost although I definitely have a boner for the tight metal! Doesn't really look like a lot going on as I would have expected!? I was ready to see SMD all over the place... I think the TM is one of the best sounding metal/rock preamp type stomps around! I like the switches, they really seem to make a huge difference in the sound/tone and the fact that it has only 4 knobs, a noise gate and fx loop is a huge plus! To me it sounds better than the triple wreck, okko dominator, openhaus etc...

[J0K3RX]

ok, I bought one and it's on it's way sooooo..... stand by

[azrael]

I have a lot of high res gut shots of the tight metal... If anybody want's to help with the schematic or layouts?
https://dl.dropboxusercontent.com/u/111 ... tal/TM.zip <<-- large download - 68megs

I have the back almost completely traced and values. All I have left to do is remove the chip from the socket and get the traces underneath and a little bit around some caps.

On the front I will remove the pots and the input and output jacks so we can see what's underneath...

https://www.youtube.com/watch?v=Gp7EnYEQNIM

Here's the back

[modman]

Ok, I missed a few traces.. removed the TL072 and now removing the jacks... correcting the back.

Trust me, I WILL get this thing!!!

Note: All 3 of the opamps are TL072's

[modman]

Ok, I removed the jacks and I am about done tracing the top...

Here are the part values as far as I can tell. I forgot the little resistor on the right side of the TL072 on the right, it's 220k. I'm not sure about all these brown resistors, not sure which way to read them? Anybody have any idea? I know, get out my meter...

Also, in the bottom left corner the 470J? cap I am guessing..?

[astrobass]

I'm not sure if the outside bands are meant to be grey or brown. Either way, they seem to follow the usual five band colour code. Here's the calculator I like to use:
http://www.diyalarmforum.com/5-band-resistor-calc/

Same site has a 4 band calculator.

[azrael]

470J, could be a 47pF capacitor. But the package is strange - might be an inductor.

Actually, if we can see how it's used in the circuit, that may make more sense.

[J0K3RX]

Crap man, they were not joking when they called this thing "Tight Metal"! Everything about it is tight especially the layout!! Almost done tracing... waiting for kid to go to bed

[jymaze]

Damn, that must be an intense mind workout tracing that thing!
For these brown resistors, I had the same problem when tracing a wampler pedal. It is annoying. Where they stand in the schematic can help choosing if they should be read from left to right or from right to left... or sometimes just one way of reading will produce a value that exist in the resistor series.

[J0K3RX]

Damn, that must be an intense mind workout tracing that thing!
For these brown resistors, I had the same problem when tracing a wampler pedal. It is annoying. Where they stand in the schematic can help choosing if they should be read from left to right or from right to left... or sometimes just one way of reading will produce a value that exist in the resistor series.

Yeah, that's what I was thinking.. If I have to I will isolate them and read them with the meter. Any idea what that light blue thing is in the bottom left corner that has 470J marking on it? I am using a high intensity LED flashlight to shine through the board from each side so I don't miss anything, kinda x-ray thang! Already found a trace that looks like it's going to a pad but it's just hanging out in the middle of nowhere... kinda like me

When I am done, is anybody up for making a schematic? I can read them good but I really suck at making them... please?

[jymaze]

I'll give it a shot! Bring it on my friend!

For the 470j, unless proven otherwise during tracing it is a470 pF cap. I think it is a multilayer PCb and this cap ties the input to ground, the ground being on am inside plane. This is why you have pads that seems to go nowhere... This is going to be fun...

[J0K3RX]

I'll give it a shot! Bring it on my friend!

For the 470j, unless proven otherwise during tracing it is a470 pF cap. I think it is a multilayer PCb and this cap ties the input to ground, the ground being on am inside plane. This is why you have pads that seems to go nowhere... This is going to be fun...

OH SHIT, if there is an inside plane!!! Didn't see anything inside with the flashlight, but?

[J0K3RX]

Ok, front and back... or whatever. I mirrored the front also so you can match them up easier..

[J0K3RX]

the blue trace hanging down on the back image is not connected to anything... unless there is a hidden plane like jymaze suggested?

[J0K3RX]

A few corrections to the front mirror trace..

[J0K3RX]

Is this a lot like the Ampeg VH-140C or is it my imagination?

[bajaman]

nice work so far

[Blend]

three resistors highlighted seem to me with these values....