Search found 15747 matches
- Tue Mar 12, 2024 8:32 pm
- Forum: Assorted Stuff
- Topic: Nothing In Particular
- Replies: 16488
- Views: 4837906
Re: Nothing In Particular
Works for me.
- Tue Mar 12, 2024 2:31 pm
- Forum: News
- Topic: Paul Messenger
- Replies: 2
- Views: 637
Re: Paul Messenger
Yep, a genuinely nice guy.
- Tue Mar 12, 2024 8:48 am
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
Even without the 1.414/0.9 = 1.57 excess voltage, I was thinking more about the cold start condition of the ECC88 that will see the entire B+ on its anode until it starts to pass current.
- Mon Mar 11, 2024 9:55 pm
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
Would need at least a 5W zener, but yes I guess so. But remember Max, adding some solid state may cause all manner of demons to fly out :-). A potential divider before the first stage would do the job, a 88 doesn't need a 80k load resistor, especially if its got a choke in there as well. Or just lea...
- Mon Mar 11, 2024 9:48 pm
- Forum: Solid State
- Topic: Germanium Amplifier
- Replies: 162
- Views: 82960
Re: Germanium Amplifier
Just a couple of thought, you are never going to be able to use much in the way of negative feedback in that amp (at least by comparison with a modern direct coupled circuit. That interstage is going to add so much group delay and general phase shifting nastyness that the most you can manage is PP v...
- Mon Mar 11, 2024 9:56 am
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
They are your valves, so up to you. I manually turn heater supplies up then b+. Two outputs on the variac, all heaters first, then b+. I always assume a unexpected short term power outage could happen, so I either make sure that the startup control is automatic, or not needed. The chokes arent inste...
- Mon Mar 11, 2024 9:07 am
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
Just remember the max anode voltage (cold) of a ecc88 is 550v.
- Sun Mar 10, 2024 9:36 am
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
can sit in an oil bath to exceed ratings. Exactly how much difference would that make? I would have expected that most of the heat from the anode was dissipated as IR (it being in a vacuum and all that) so how directly is the envelope temperature related to the max dissipation? I suppose it would a...
- Thu Mar 07, 2024 10:45 am
- Forum: News
- Topic: Paul Messenger
- Replies: 2
- Views: 637
Paul Messenger
Will be missed, One of the good ones.
- Thu Mar 07, 2024 10:24 am
- Forum: Everyones Projects
- Topic: 6550 SE Amplifier
- Replies: 110
- Views: 10805
Re: 6550 SE Amplifier
Thorston always was one for his brand. And trying to add a bit of woo by claiming that electrons have no reality is typical of that. The Standard Model may have a view on that
I am with him with the no such thing as ground though
I am with him with the no such thing as ground though
- Tue Mar 05, 2024 10:58 am
- Forum: Everyones Projects
- Topic: OK…so I’m on wi’ summat
- Replies: 193
- Views: 43565
Re: OK…so I’m on wi’ summat
I have to be careful here as I have gone over to the dark side now, but I think that the preference for small caps in valve amps has two attractions. First, as Paul mentioned, taking the LF down too far just highlights the lack of flux in the output transformer, Secondly, if you have solved the flux...
- Mon Mar 04, 2024 12:35 pm
- Forum: Everyones Projects
- Topic: OK…so I’m on wi’ summat
- Replies: 193
- Views: 43565
Re: OK…so I’m on wi’ summat
Probably Dave or Paul Joppa referred to the fact that protecting the se transformer from too much bass results in better bass. I think the tank effect referred more to the parafeed cap resonating with the two inductors in parallel (choke load and parafeed transformer) so I suppose you see a resonan...
- Mon Mar 04, 2024 8:41 am
- Forum: Everyones Projects
- Topic: OK…so I’m on wi’ summat
- Replies: 193
- Views: 43565
Re: OK…so I’m on wi’ summat
I have not tried it with a output stage, but certainly with interstages, small cathode caps can work a little different than you would from those calc's. The fact that you have a inductive load instead of a resistive one can give you a small (though helpful) inductive peak at LF via the LC circuit c...
- Fri Mar 01, 2024 3:15 pm
- Forum: Assorted Stuff
- Topic: The Quackery Thread
- Replies: 360
- Views: 192938
Re: The Quackery Thread
have never yet been really cold. If you have never been, I can thoroughly recommend Iceland. Iceland's a doddle! Lovely as it is (we really like it), it's not that cold... Try spending a winter in Newfoundland and Labrador - we hit -40C (before windchill) in Labrador which I remember well as it's t...
- Fri Mar 01, 2024 2:24 pm
- Forum: Assorted Stuff
- Topic: The Quackery Thread
- Replies: 360
- Views: 192938
Re: The Quackery Thread
If you have never been, I can thoroughly recommend Iceland.have never yet been really cold.