Based on the very expensive 'Gaincard' amplifier, the Gainclone is built by many audio enthusiasts, myself included. I have built several versions of this amp (well, it is not one single circuit, but more of a concept based around the National Semiconductor LM38xx chips).

One of the best guides I have seen online is this one: www.decdun.me.uk -- I followed this carefully and have had many enjoyable hours listening to my amp. My current plan is to make an 8 channel version for a surround sound, home cinema setup

Hope this is of some use to someone.

Although I haven’t used the National Semiconductor chips, I am currently using a pair of Phillips TDA1514A for my mids and tweeters. For sheer simplicity these types of one-chip amps are great.
I’m also contemplating using multiples for a surround amplifier, probable use the National as they are a bit cheaper.

DJ

Yes, the Gainclone is a really nice chip amp. VBery popular for DIY audio, since it's reasonably simple to build, you can even get perfectly acceptable results building it on breadboard (Though I'd recommend against that )

Well, I have looked at a few of the sites now and I must say that I am intrigued. I hardly understand any of it, but I am seriously thinking of giving this a go.

SJ

You can even make them with no PCB as long as you are neat with the wiring. A couple of chips, a few resisters, some capacitors and a transformer and you have yourself an amp. Couldn’t be simpler.

DJ

I've built a couple of these: Elliot Sound Productions Project #19 which is kind of a gainclone clone. It's independantly developed based on the National Semiconductor LM3876 IC amplifier chip. Definitely a nice piece of kit, I use them for (realatively) low power applications, and they're very nice. They make a good high frequency amp when paired with something with a bit more grunt to handle the low end.

Also highly recommendable (by me) is the project 09 (L-R aligned active crossover) and the project 88 (Simple pre-amp)

I've also built boards for project 3A (60W discreet component amplifier) and project 68 (300-500W discrete subwoofer amplifier.) also project 101 (100W MOSFET amplifier) These are VERY nice circuit boards, and the amplifiers are also very nice.

I think just about all the projects on that site are great. Rod Elliott has a very down to earth way of explaining things. He tells it like it is, just enough techno talk and no BS.
Do you make your own PCBs or just buy them?

DJ

At the price that he sells the PCBs I think I'd have to be insane to make my own.

I did make a P19 PCB, but it's easily twice the size of his. I did that just as an exercise in PCB design. I could cheat now and look at his design, where I've already seen several examples of 'where I went wrong' but it basically shows that I'm not as good at it as he is. When you add the silkscreening and pre-tinning of the traces (Solder masks even on some boards) it's absolutely not worth the hassle of making my own. Even with a photographic process kit, it's still nowhere near as good.

I've bought PCBs for P3A, P09, P19, P05, P68, P101, P84, P88. I've been very impressed by the quality of all of them.

I built a set. They work well, but it was more for fun that anything.

Needed lots of stupid little stuff to make it safe, friendly and actually useable.

I think they are in a box now, collecting dust.

//didn't waste $ on a PCB