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    Building, troubleshooting and testing of these amplifiers should only be
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100watt mono blocks

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Hi guys I'm interested in building a set of 100watt mono block tube amps. From reading some of the posts and looking at other peoples amps, I realize that this is a pretty big undertaking especially for me as this will be my first diy project. With that being said all prayers and any help are welcome. :) Does anyone know if there are any schematics available or projects that are similar that I could glean some info from?
 
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100 W monobloc is by no means out of the question. Just don't try to do it with one pair of PP tubes - parallel PP is a far better idea. KT88s or 6550s in PPP class AB1 UL mode should be capable of providing 100 W or more of clean power.

The biggest factors for success are going to be the output transformer and the power supply. The PS needs to be well capable of providing the required current without much sag. You'll need seriously big and heavy trannies, together with the chokes you'll probably want to use, and the total weight of the hardware is a good reason why you're wise to consider monoblocs, IMHO.
 
one schematic you might want to take a look at (it's a starting point) is this Genelex at Bonavolta:

http://www.bonavolta.ch/hobby/en/audio/kt88_6.htm

HT on this sucker is about 560V, which will give you 100W at 5% distortion. This figure is somewhat reasonable as you'd never need consistent power at 100W. I'm aware that it's not ultimate-HIFI, and that it only has two tubes at the output, but it's still reasonably interesting.

The full book that explains the circuit is here at

http://www.pmillett.com/Books/GEC_approach.pdf

I advise you to take a look at some other books on that site as well, it's well worth it.
 
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