Quote from: martyfriedman86 on October 19, 2006, 12:08:25 PM
thanks!
I'll post later when y try it

Thanks a lot

btw, i got the apollo booster to work (the pot wasn't working, please don't hit me)

You'd be surprised how often it is a crappy pot causing problems.  No worries, we won't hit you 

That makes more sense (about the caps).  And as far as being indecisive, no problem, I think it's great that you are designing these.  There isn't really any sort of good SS amp to build right now that isn't a chipamp.

The chip lists a max of 96v, which would be +/-48v, with the tranny you are have you would get +/-56v, too much.  Sorry.

What are you using for a preamp?  And are you using this for guitar as I would assume?

Quote from: Joe on October 17, 2006, 11:23:03 PM
http://www.diystompboxes.com/analogalchemy/tmp/

Pix of inside and front panel, and dirty socks. It's a recycled Fender combo.

This is not how to build an amp, it's a rough test built from junk. I'm not particularly thrilled with the power amp, it works alright but seems it could be better.

I think it looks good, except the large caps sitting on the chassis on the right.  That looks sketchy.  So whats the matter with the power amp?  Doesn't sound good?  That's the part I'm really interested in as I already own a preamp box (marshall DRP-1) and I'm working on a TL071 preamp.

What I mean is, as far as I can tell there is no LED in the schematic.  So where is it located?  Is it just connected to the stomp switch so that it lights when the effect is "on" and is off when the effect is bypassed?  Wiring the switch can be confusing.  If you can't get it right the first time, take out the switch and see if you can get the circuit working properly, then worry about adding in the stomp switch.

How do you guys like your LM1875 kits?  We spread out quite a few kits, it would be nice to know how well they are working.

What LED is this?  I see you have a 3PDT switch, is this the "effect on" LED?  If so, it seems maybe you have your switch wiring improperly.

Well, with that many pots, there is a good chance of one or more of them not being in the "right" position so it wouldn't work.  I would play with those first.  Also, make sure you are plugging your guitar into the right jack, when you have it backwards sometimes pedals will do what you are describing.

Just noticed that looks like a lot of pots to me.  I would try substituting some of them for different value resistors, or even better, go off a proven schematic like this one:



That's the one I used, it has two knobs and works well.

I still wanna see pics :-)

Thats great, looks like we should be able to do some cool stuff with this.

This is looking really great!  Correct me if I'm wrong, but wouldn't this work with other preamps pretty ok as well?  I have a marshall preamp I'm using on my 50w LM3886 amp right now, and I'm working on a preamp based around the TL071 which is probably what I would use on this.  Is it possible to get any pics of the amp guts all put together?

**edit**
Also, any ideas on what the minimum/maximum would be for the voltage on the transformer?  I can get a 36v (18v+18v) transformer with 160VA pretty easily, but I don't want it to be too much, and the next one down that I have is a 25VCT @ 2amp.

WOW!  This is great!  I can't wait to get some people building a few of these so we can really test 'em out.  It would be cool to have a non-chip amp SS 30watter.