New PP Pentode Monoblocks

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Mike H
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#181 Re: New PP Pentode Monoblocks

Post by Mike H »

:lol:
 
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#182 Re: New PP Pentode Monoblocks

Post by Cressy Snr »

Now then Mike,
That amp of yours is a superb little bugger. Great job!
I think the both of us managed to further slightly, the push-pull pentode cause :wink:
Don't forget the pics when it has been boxed up. :)

Sitting here this morning with Pat Metheny's "One Quiet Night" album wafting out of the Mets, via the pentode monoblocks,
I really couldn't ask for much more.
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Mike H
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#183 Re: New PP Pentode Monoblocks

Post by Mike H »

Yes Ant's making me a plinth type case for it.

Got a couple of Pat Metheny don't think I got that one tho, will have to investigate...


As you said elsewhere the amp has in theory "all the wrong bits" plus common-or-garden elecs and penny each carbon resistors from Rapid, but when I first got it playing I was genunely flabberghasted.
 
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pre65
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#184 Re: New PP Pentode Monoblocks

Post by pre65 »

Mike H wrote:
but when I first got it playing I was genunely flabberghasted.
Never has your flabber been so ghasted. :lol:

Well done to the push pull pentode boys. :)

If only Nick had not shown us his mosfet experiment amp. :wink:
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Mike H
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#185 Re: New PP Pentode Monoblocks

Post by Mike H »

pre65 wrote: Never has your flabber been so ghasted. :lol:
Frankie Howard. :D
 
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#186 Re: New PP Pentode Monoblocks

Post by Cressy Snr »

No....no....listen.....LISTEN!.....ooh...no...no....Don't titter......TITTER YE NOT! :lol:
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#187 Re: New PP Pentode Monoblocks

Post by Cressy Snr »

Final tweak has been done.
Late in the day during construction of these amps, I had decided to incorporate a slow-start system using a single TV damper diode at the output of the solid-state rectifiers.
I had only had a couple of knackered Chinese magnoval sockets, so had been restricted to a pair of EY500A, these being the only ones that had worked in the sockets, without arcing at the pins.
I was far from happy with the way these flopped about in the ratty old sockets, so finally, last week bought a couple of NOS British ceramic, novar sockets off Langrex and have fitted these this afternoon.

Having the novar sockets, I was able to use my pair of GE 6CL3, which don't use top caps, and are not overkill in this circuit, as were the EY500A. The 6CL3 only use 1.2A of heater current compared to the 2.1A of the EY500A.
The 6CL3 has a 250mA steady state current capability, with 1.3A peak; perfectly adequate for these monoblocks.
The 6CL3 can be seen hiding behind the right hand 6CA7.

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Mike H
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#188 Re: New PP Pentode Monoblocks

Post by Mike H »

Image
 
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#189 Re: New PP Pentode Monoblocks

Post by Cressy Snr »

:)
No more floppy slow-start diodes and the sound just gets better as the amps burn in.
I've never been happier with the sound of the system.....it's bliss, and what an unlikely direction
for this pleasure to come from; push-pull pentodes. Who'da thunk it? :lol:

How are your EL84s doing?
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#190 Re: New PP Pentode Monoblocks

Post by Mike H »

Super, thank you! :D As you say does the job surprisingly well ~ DTB thought pentode mode could be "fatiguing" but haven't had any of that yet. Often I've not gone to bed 'til 2 - 3 am cos can't stop playing stuff on it.
 
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#191 Re: New PP Pentode Monoblocks

Post by Dave the bass »

Mike H wrote:DTB thought pentode mode could be "fatiguing" but haven't had any of that yet.
Yups, it was Flopp's EL84 amp built from the Elektor magazine. It was an 'exciting' listen, but long term it wasn't an easy listen IME.
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#192 Re: New PP Pentode Monoblocks

Post by pre65 »

There was only one setup at Owston that "offended" my ears, and it was not the pentodes of Steve or Mike.

What I heard of those two certainly seemed to bring out the best in their respective speakers. :)

I can't comment on the long term effects though. :wink:
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#193 Re: New PP Pentode Monoblocks

Post by pre65 »

Dave the bass wrote:
Mike H wrote:DTB thought pentode mode could be "fatiguing" but haven't had any of that yet.
Yups, it was Flopp's EL84 amp built from the Elektor magazine. It was an 'exciting' listen, but long term it wasn't an easy listen IME.
Is that relevant to the amps Steve and Mike exhibited at Owston ?

PS Did you change the post content 'cos I thought it was "different" a few minutes ago. :?
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#194 Re: New PP Pentode Monoblocks

Post by Cressy Snr »

Mike H wrote:Super, thank you! :D As you say does the job surprisingly well ~ DTB thought pentode mode could be "fatiguing" but haven't had any of that yet. Often I've not gone to bed 'til 2 - 3 am cos can't stop playing stuff on it.
Good stuff!
I haven't had any fatiguing listening experiences either. On the contrary, as with yourself, I often have the music on for hours on end and late into the night.
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Mike H
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#195 Re: New PP Pentode Monoblocks

Post by Mike H »

pre65 wrote: Is that relevant to the amps Steve and Mike exhibited at Owston ?
Certainly if it's same o/p stage, which I'm assuming it is. :D
 
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