New PP Pentode Monoblocks
- Mike H
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#181 Re: New PP Pentode Monoblocks
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- Cressy Snr
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#182 Re: New PP Pentode Monoblocks
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
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.
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
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.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Mike H
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#183 Re: New PP Pentode Monoblocks
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.
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.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- pre65
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#184 Re: New PP Pentode Monoblocks
Never has your flabber been so ghasted.Mike H wrote:
but when I first got it playing I was genunely flabberghasted.
Well done to the push pull pentode boys.
If only Nick had not shown us his mosfet experiment amp.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- Mike H
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#185 Re: New PP Pentode Monoblocks
Frankie Howard.pre65 wrote: Never has your flabber been so ghasted.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- Cressy Snr
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#186 Re: New PP Pentode Monoblocks
No....no....listen.....LISTEN!.....ooh...no...no....Don't titter......TITTER YE NOT!
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Cressy Snr
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#187 Re: New PP Pentode Monoblocks
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.
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.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Mike H
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#188 Re: New PP Pentode Monoblocks
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- Cressy Snr
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#189 Re: New PP Pentode Monoblocks
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?
How are your EL84s doing?
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Mike H
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#190 Re: New PP Pentode Monoblocks
Super, thank you! 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.
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."
- Dave the bass
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#191 Re: New PP Pentode Monoblocks
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.Mike H wrote:DTB thought pentode mode could be "fatiguing" but haven't had any of that yet.
"The fat bourgeois and his doppelganger"
- pre65
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#192 Re: New PP Pentode Monoblocks
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.
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.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- pre65
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#193 Re: New PP Pentode Monoblocks
Is that relevant to the amps Steve and Mike exhibited at Owston ?Dave the bass wrote: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.Mike H wrote:DTB thought pentode mode could be "fatiguing" but haven't had any of that yet.
PS Did you change the post content 'cos I thought it was "different" a few minutes ago.
The only thing necessary for the triumph of evil is for good men to do nothing.
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
Edmund Burke
G-Popz THE easy listening connoisseur. (Philip)
- Cressy Snr
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#194 Re: New PP Pentode Monoblocks
Good stuff!Mike H wrote:Super, thank you! 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.
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.
Sgt. Baker started talkin’ with a Bullhorn in his hand.
- Mike H
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#195 Re: New PP Pentode Monoblocks
Certainly if it's same o/p stage, which I'm assuming it is.pre65 wrote: Is that relevant to the amps Steve and Mike exhibited at Owston ?
"No matter how fast light travels it finds that the darkness has always got there first, and is waiting for it."