The little gem is a great starter amp to build.  It is by far the easiest guitar based circuit I have put together and sounds great.  I would recommend the original Little Gem personally, http://www.runoffgroove.com/littlegem.png

It is only 1/2watt but it sounds great and is loud enough for practice situations by yourself.  If you want more power than that, I would recommend building a LM1875 based amp. 

Depends on what you are building.  To build one of my 5th Gear Overdrive pedals it costs about $35 in parts from smallbearelec.com

Just the size.  IE - instead of a 0.047uF cap, try a 0.1uF etc.  Or instead of 2.2k try a 5k resistor.

Thats not necessarily going to be an issue, he needs new people to test them as well to make sure they go together easily.  If you are interested, shoot him an email and tell him you are an SSGuitar.com member and are interested in beta testing one of his LM1875 kits.  He should be able to hook you up with a kit for nothing, or really cheap.

Quote from: iTzALLgoOD on April 15, 2007, 04:54:06 PM
So many options ans so little money

haha, bingo.  btw, Brian (chipamp.com) is looking for people to beta test his LM1875 kits right now.

No one (that I know of) has used a little gem for a preamp permanently, but I have played with mine like that and it worked quite well.  So yes, that would work.  You could even have one little gem circuit with a pot on the gain so that would control how dirty it is.

The preamp is something that is still pretty much in preliminary stages here, but what I can recommend is using two clean preamps, then make them switchable.  Take one of the clean ones and run a distortion infront of it (built into the circuit), it's easy since many distortions are only a few components.

uF, but its always a good idea to ask, so no worries  :tu:

Quote from: soren_jepsen on March 27, 2007, 02:37:28 PM
I was probably not formulating myself too well 


I realize the need for diodes (or a bridge). But those MUR860 are impossible to find i Denmark. Are there any good alternatives? What about bridges?

Ah, I didn't get that part.  Well, you could (as teemuk mentioned) get some other diodes that fit the bill, or you could pay me shipping and I could send you a few MUR860 diodes.  I have four of them sitting around from a group buy I did a while ago where I had some extra parts.

Looks pretty good, I'll be excited to see how you like it once you get it going.

Well you have to use diodes to rectify the AC to DC, Brian's PSU is arguably the best design possible for the amp, so that is the one I recommend.  I'm sure there are other options however, I just don't know what they are. 

I wanna see the insides  :grr

Looks go so far though  :tu:

Interesting using a TL072 as a preamp chip for the LM386.  Oddly enough I'm messing around with the LM386 as a preamp chip haha.  Looks like a cool amp.  Do you have any sound clips?  Or pictures of the build?

Oops, sorry to be misleading.  You are right, the Ruby uses a single LM386, I was thinking the Little Gem MKII as suggested by Syndromet.  I think that would be a better circuit for what you are thinking of doing.

I can vouch for TDA2003s not sounding so good, but it should get the job done.