JJ 2A3-40 DHT Single ended triode, power amplifier

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wiicrackpot
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by wiicrackpot » Wed Nov 01, 2017 7:58 pm

Rose Gold is totally in keeping with that amp, very cool or should it be 'hot'. 8-) :grin:

Not a criticism Steve but have you thought of side cheeks with handles like Allnic amps?,
the thought of moving/lifting it with all those trannies is hernia inducing i'd have thought,
plus my suggestion would come in handy if you thread the IC's through the handle to keep it from touching the 2A3's or is it 300B's,just a thought. :idea:

p.s. how deep is that amp.

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karatestu
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by karatestu » Wed Nov 01, 2017 8:11 pm

Excellent work Steve. Never built a valve amp only SS.

You can never have too many tweeters :lol:
Naim, Linn & Harbeth fanboy

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CycleCoach
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by CycleCoach » Wed Nov 01, 2017 8:33 pm

I hope it sounds as good as it looks. Good work Sir!
Current System: Macbook Pro, Starting Point Systems DAC 3, NVA A20, NVA P50SA, NVA LS2, Rogers LS4a

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SteveTheShadow
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by SteveTheShadow » Wed Nov 01, 2017 8:59 pm

CycleCoach wrote:
Wed Nov 01, 2017 8:33 pm
I hope it sounds as good as it looks.
Oh yes. 8-)
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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SteveTheShadow
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by SteveTheShadow » Wed Nov 01, 2017 9:14 pm

wiicrackpot wrote:
Wed Nov 01, 2017 7:58 pm
Rose Gold is totally in keeping with that amp, very cool or should it be 'hot'. 8-) :grin:

Not a criticism Steve but have you thought of side cheeks with handles like Allnic amps?,
the thought of moving/lifting it with all those trannies is hernia inducing i'd have thought,
plus my suggestion would come in handy if you thread the IC's through the handle to keep it from touching the 2A3's or is it 300B's,just a thought. :idea:

p.s. how deep is that amp.
If it wasn't a visual design exercise in 50s art deco revival, there would have been handles. However, it is not too bad a lift and I'm used to handling valve amps. :)

I'm off to Maplins tomorrow for a pair of right angle phono plug adaptors. These will lower the cables towards the deckplate, so they will be running well away from the glass of the 2A3 bottles.

The amp is 18 inches across, 14 inches front to rear and 10 inches from the equipment table surface to the tops of the 2A3 valves, so it's a big b'stard. Having said that there are plenty of stupidly expensive valve and solid state power amps that are a lot bigger. :)
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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wiicrackpot
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by wiicrackpot » Wed Nov 01, 2017 10:35 pm

There you go, how things deceive the eye,
i really thought by the look of it on your pic it's about the same as the front which i guess at 19'' inches,
good idea with the right angle adaptors. 8-)

antonio66

Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by antonio66 » Thu Nov 02, 2017 6:04 am

"However, it is not too bad a lift and I'm used to handling valve amps. "

That's confidence for you. :lol:

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SteveTheShadow
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by SteveTheShadow » Tue Nov 21, 2017 8:26 pm

Image

The finished amplifier now has right angle phono adaptors to get the interconnect cables
down on the deckplate rather than have them sticking up in the air.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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wiicrackpot
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by wiicrackpot » Tue Nov 21, 2017 9:42 pm

Neat, 8-) where did you source the adaptors Steve?.

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SteveTheShadow
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Re: JJ 2A3-40 DHT Single ended triode, power amplifier

Unread post by SteveTheShadow » Tue Nov 21, 2017 10:07 pm

Got them from Maplins a few years ago. My son had them a while, then gave them back.
BTE Designs modified Lenco L75 idler turntable, Rega R200 Tonearm, Goldring E3 MM cartridge, NVA Phono1 phono stage.
Mac-Mini music server with iTunes, AppleTV4 media streamer, Musical Fidelity M1 DAC,
NVA A20/P20, 25WPC stereo power amplifier/passive control unit,
own design, semi-omnidirectional, transmission line speakers- "The Flatback Banned".

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