• 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.

Photo Gallery

Rodango said:



Yes, you're right. I wasn't going to use them originally but I had had Heybohr custom make me some TO-350s. They screwed them up so I got the 1650Rs because I was tired waiting. But I am VERY PLEASED with them! They do a great job...

OK guys, I can hear some of you still laughing out there... "He said no expense spared and then he gets Hammond outputs?! Oh that's too funny! Ha ha ha!"

OK.. Agreed.. The outputs are the only things I skimped on. BUT I'm here to let you know I just redeemed myself and ordered a set of Hashimotos.

So in a couple weeks, we'll see how they 'transform' the AAI!!
 
The Blunderbuss

Here's a really great hand-made amp I bought off ebay. Perhaps some of you recognize the trademark mirror and know who the builder is. I modded it quite a bit including re-doing the power, adding gold connectors, Sonicaps, different cathode resistors and bypass caps, tube shields, NOS Dynaco A-470 outputs and Brazilian Ebony endpieces.

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Hi Rodango

What tubes do you use in this amp ?

Dynaco A-470 is wired for 35W, 20-20kHz.
If you push it with more effekt, frequency drop dramaticly in both the low and high frequencies.

The A-430 transformer were wired (with its doubble weight) for 60W, 20-20kHz. I use the capsuled ones myself for my klassA amp in Post #1976.

Be carefull.
 
Rodango

Don´t misanderstand me. The A-470 is a very good transformer, but its built in the first case for use with EL34 and 6L6 etc.

With A-430 or Hammond 1650R, you can go with tubes like 6550, KT88, KT90 and KT100. And you are on the safe side, to get the best sound and reliability out of it.;)
 
EICO HF87 Rebuild - (Pics)

EICO HF87 Rebuild.... This is not a faithful restoration project, as the Olive Drab of the original unit just isn't my style. I ditched the original schematic and went with my own. The amp sounds amazing... it's one of the best of the oldies.

The wonderful original EICO output transformers, stripped for painting.
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The HF-87 chassis stripped and sanded down to bare metal.
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A thick glaze of copper paint applied to the chassis.
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The EICO transformers back together and ready to place on the chassis.
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Transformers in place on the HF87 chassis.
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Starting to wire the outputs.
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A shot of the back of the amp.
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Bottom panel.
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The final amp driving a pair of Monitor Audio RS1 Silvers.
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The final amp driving a pair of Monitor Audio RS1 Silvers.
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EL34s in the dark...
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Hi guys'n girls (if there are any ;) )

Here's my small contribution to the gallery.
My RIAA called Rialto, together with my Puccini, a downsized Maynard 25-8, and a passive preamp called Verdi :)

The circuit is a copy of the danish Tube Lab (from Fairman), from whome i got the diagram some years ago.
To my question on whether I could just get it for free he (Werner Scherrer-Tangen) just smiled and said that it was just the diagram.
Now, many years later, I understand what he meant :xeye:
 

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pedroskova said:
Thought I'd throw in my brother's 6sn7/300B P-P monoblock that is finally becoming a reality. It was built in partnership with an old friend of his. Chas(my brother) was responsible for the layout and construction of the chassis(machining, veneering,etc.,), while Mike designed and prototyped the circuit.

It's made of polished aluminum plate and veneered mdf, and has hundreds of hours put into the machining, etc., (for all four units). The transformer cover is fiberglass that was laminated over a mold and will have artwork applied.

Not your everyday amp.:)


Hey how you polished the aluminium? i tryed many times without luck :(