DIY powerhouse amp

[pjpoes]

Hey guys, I have been wanting to build a large amplifier for a while now using some plans or premade pcb's if possible. I know the expense is going to be large, but I think it might be a worthwhile project. I was wondering if anyone had any recomendations on amplifier designs, especially if they have PCB's available. I have been looking at some kits from Aussie Amplifiers, they have a few that can do between 400 and 500 watts into 8ohm's.

I'm really looking for something that can work sort of like the large Classe, McIntosh, or Accuphase amps, which I only mention because I have heard those three. Though they all had issues, I thought they had a level of effortlessness like nothing I had heard before, and I have a secondary system with a large set of speakers I think would love them. Let me know if you have any idea's for me.

[stidrvr]

Have you checked out Ampslab? They have some promissing looking kits.

[pjpoes]

The more and more I look into this idea the worse and worse the idea looks. I knew it would cost more than a simple amplifier, but it seems that any of the kits designed to produce the kind of power I was thinking are not considered acceptable for audiophile use. Anyone know why that is, is it because of non-linearities between all the so many pairs of output devices, would you have to try and match every single one of them to get good sound. Maybe I should start with an exapandable setup and try 1 set of output devices, then 2, then see how it goes.

[MadMax]

Hi Pjpoes
Have you looked at the leach superamp, not as high powered as you talk about but I have built both the leach amp and the superamp and I think they are good amps, better than any thing I could afford to buy at any rate here is the link http://users.ece.gatech.edu/~mleach/superamp/
not a simply amp to build but good plans at above site
good luck Max

[richie00boy]

The people making complaints about the sound are wrong about proper high power quality kits IMO. For cheap to midrange PA gear then yes, but high end PA and good kits are amazing.

You problem will be as a beginner building anything high power, it's better to cut your teeth on some lower power, simpler projects first.

[djk]

The Leach Superamp was available commercially as the Heathkit AA1800 and put out in excess of 400W into 8 ohms. It used the MJ15022/23 as opposed to the MJ15003/04 listed on the Leach BOM.

It is very easy to pump up the smaller Leach to as much as 1KW per channel into 2 ohms.

Depending on your supply details either amp will put out whatever you need.

[jaycee]

I do often wonder why people need 500W for Hi-Fi use, unless they're using some seriously inefficient speakers. This is probably why most high power amplifiers are aimed at PA usage where quality isn't as critical.

[AKSA]

Couple of points here to note.

1. Powerful amps usually have protection circuitry built in, as much to protect expensive speakers as anything else. Often, these circuits are sonically intrusive.

2. Powerful amps always have at least three pairs of outputs, and all the devices of each side must turn on and off together. This is a tough call; the simpler amps with two pairs or even a single pair of devices are much better sounding because the crossover zone is better handled.

3. Powerful amps are usually made for large, multiple drive speakers which often measure 4R or even less. So they are current delivery components for large speaker arrays. If you have a home system, you won't be using very low impedance speakers, and such an amp is probably overkill.

4. A 100W into 8R amp is actually more like 200W into 4R, depending on the power supply. If the amp is properly designed, and carries no intrusive protection circuitry, there's little risk and it will sound very very powerful in a domestic setting.

There are quite a few 100W/8R amps in the DIY category, including the AKSA, so look around. Often they sound pretty good, too!

Hope this helps,

Cheers,

Hugh

[CBS240]

I don't see why such power is needed in a home. Hope you have thick glass windows! Why listen to something that you have to have ear protection against? Don't recomend you try to make yourself deaf. Go for quality, not quantity. It's the best route for home.

[djk]

Maybe he owns something like B&W 801s, they need the juice to really sing.

Anyway, 500W is only about twice as loud as 50W.

Hugh is right though, if 100W doesn't do it for you, you probably have a big problem.