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    Building, troubleshooting and testing of these amplifiers should only be
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7 ch Amp kits?

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Please be patient guys this is my first post here.

I have been looking for a new amplifier to power the speakers in my HT, all of which are Polk Audio Lsi series, rated at 4 ohms nominal. and 88db eff. The manufacturer states that they can be driven by an amp rated from 20 to 250 watts. I recently borrowed a 7 channel Anthem amp from a local A/V shop that I thought would work but I am leaning toward a DIY tube amp.

So, anyone out there know of a 7 channel kit, with or without a chasis?

Budget? I really have not given it much thought yet, kind of depends on what looks/sounds good!

BTW, if you want to look at my current setup just click on the WWW button down below.
 
diyAudio Senior Member
Joined 2002
7 CHANNEL ht

Hello Frank Z,

Personally I have never come across anything like that with tubes.

So here are just some preliminary thoughts:

Assuming a 4 Ohm impedance for each speaker that would either make for 3 stereo amps + 1 mono(ed), I assume (I am no HT expert) for a summed channel sub or a set of stereo amps with especially wound OPTs sporting dual 4 ohm windings.

This can be made but I would like to call some HT expertise before advising any further.

Regards,:)
 
3 Channel..

You'd want a 6channel amp..I think?... power the subwoofer with a solid state amp..
With 6 channels...you'd want something without 300B tubes...unless you are loaded...

So go for something like push-pull 2A3...or single ended gm70 a russian 845 look alike (Price of a pair of GM70) $45US.

Here is my 3 channel amp.. rear 2 channels will be driven by solid state...and eventually the subwoofer ...also with solid state..
 

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Frank Z said:
I have been looking for a new amplifier to power the speakers in my HT, all of which are Polk Audio Lsi series, rated at 4 ohms nominal. and 88db eff. The manufacturer states that they can be driven by an amp rated from 20 to 250 watts. I recently borrowed a 7 channel Anthem amp from a local A/V shop that I thought would work but I am leaning toward a DIY tube amp.
How hard were you cranking the Anthem, ie, how loud do you like to listen? I need to know this to get some idea of the power you're going to need. Watts=dollars and your speakers are not very efficient and your room is a reasonable size (bigger room = more watts). At a guess, 50W ea for the 3 mains, 20W or so for the others. These are the MINIMUM power, double will be better if you like it loud, and have deaf neighbours or a basement setup.
So, anyone out there know of a 7 channel kit, with or without a chasis?
Not that I'm aware of. Build 7 chassis, or as fdegrove suggests, 3 stereo and a mono, and set the power levels for what's needed. The R/C/L do 70-80% of the work.
Budget? I really have not given it much thought yet, kind of depends on what looks/sounds good!
Seven channels of tube amplification are going to cost a lot more than a receiver of the same power and put out a fair bit more heat. As for budget, even modest amps at the power levels I mentioned above could run to a couple of grand for scratch builds, and more for any kits you might find, up to a lot more if you want to go aal out with them.
Don't scrimp on the power, or the quality of the 3 mains. The other 4 you can build cheaper and you won't notice much of a difference.
 
Why not try a hybrid?

Is it just me or do you want the valves (or tubes for you guys) just for the look of them. Look at http://www.anidian.com/audio/construct/p3a_adden2.shtml for a P3A with a 5687 valve driver. This might give you both the power for HT and the visual appeal of a valve. Also a good resource on power supply design for the P3A if you look around a little. Personally valves seem like a lot of effort compared to SS.
 
Valves for multichannel

It is not a very good idea of having a multichannel setup using valve amplifiers since, by design, they introduce an enormous level of phase distortion that will ruin the surround effect. On top of this it is a waste of money. If you still need to spend that much money, i can send you my paypal address!
 
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