• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Any plans to build a 100W per channel power amp?

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I agree with the assessment that the price asked for a set of "Deuce" transformers is nucking futz. :mad: A complete, unrefurbished, "core" should not cost that much.

The O/P transformers used in the Cit. 2 and the Heath W6M are very special and I don't know if satisfactory "clones" of either can be purchased. Good O/P "iron" is always EXPENSIVE. :bawling:

Maybe you could make something loosely based on the Heath W6M around the Plitron PAT-2100-SSCR O/P transformers, whose full power bandwidth is excellent. Even though the "finals" operate in UL mode, g2 B+ gets regulated for superior open loop linearity. Williamson style circuitry has plenty of NFB, for a decent damping factor. FWIW, I would use a "high" current/"low" plate voltage KT88 operating condition set, to compensate for the comparatively low primary impedance.

BTW, I would adjust the W6M's small signal tube lineup/circuit details to make the gain structure compatible with unattenuated 2 VRMS I/P signals and more linear.

my experience so far with regulated G2 has been very happy indeed, to me they sound better than ultralinears.....thanks for the post, i also like the "high" current/"low" plate voltage KT88 operating condition set.......
 
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Even if you can buy the transformers from ARC, they are going to cost you an arm and a leg... For your $1k budget, I think you are pretty much stuck with off-th-shelf xmfr's from Hammond, Edcor and Heyboer. For the PCB's take a look at Pete Millett and Tubelab, they are proven designs and offer relatively low cost solutions.
 
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Oh NOOOOOOOO...:D

Velleman nv - Item - Details - K4040

Case and everything all done..I know a few people that have used them for the last 10 years..
You can bias double and tube roll as well..but its only 95Watt per channel..tusk tusk..

I,m not happy I want the other 5 watt per channel ...:D

But you get everything..I don't care its only 95W per channel...LMAO Power Tx output Tx and everything..Huh I have to add a switch for U/L and triode..

Regards
M. Gregg
 
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I remind everybody that the OP's speakers require both a substantial damping factor and a high current, SS rectified, PSU.

The Class "AB2" Williamson arrangement of the Heath W6M should meet those needs. Make the PSU "beefy" and tweak the operating conditions of the "finals" to make the speakers play WELL. The speakers are driving the amplifier decisions. The behavior of those speakers seems to be more or less along the lines of AR3s and AR9s. Wimp amplification need NOT apply.

Plitron's PAT-2100-SSCR is expensive at 441.63 USD/Q1. IMO, the "best" way to buy that "iron" is as a group. The price comes down to $382.03 each for 10 pieces and additional per trafo discounts are available at higher volumes.
 
For the PCB's take a look at Pete Millett and Tubelab, they are proven designs and offer relatively low cost solutions.

None of my current PC boards meet the power requirement, although I am working to fix that! For this reason I mentioned Pete's Engineer's Amp. he specs it at a conservative 18 WPC.

Pete's Engineers Amp is adaptable to 100W/Channel. Several people have pushed it beyond that.

Being an engineer, I bought one of Pete's boards and told him that I would be disappointed if I didn't get at least 50 WPC. That took about 10 minutes (different transformers). I tinkered with the amp off and on in my spare time until I was getting an honest clean 250WPC and 300 WPC at clip. I even paralleled both channels to get 504 watt, with 525 watts at clip.

I then published the recipe for a 125 WPC version that has been built by a dozen or so people. See this thread

http://www.diyaudio.com/forums/tube...ower-amp-design.html?highlight=push+pull+6jn6

Jump to post #438 to see the super sized version in action.

Realistically to get 100WPC from ANY tube amp you are going to spend most of your budget on transformers. The Edcors needed for a 100 WPC amp will cost about $400 including shipping to Florida. Plitrons......well there goes the kilobuck.
 
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