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Old 3rd April 2003, 08:47 PM   #11
dhaen is offline dhaen  Europe
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Brett,

I too looked at the "Outerlimit" in awe.
When I asked Benny for the capacitance of the choke, he said he didn't have it, but the resonant frequency was 1 or 2MHz. I couldn't believe this, and asked a transformer winder if it was possible. He said no. Also with a 10K primary, he said there is just too much total capacitance for good HF performance.
I think it is an attractive method, but for lower impedance anodes.

Cheers,
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Old 6th April 2003, 09:37 PM   #12
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Default PARAFEED.

Hi,

Quote:
I've found that by tuning the cap to under the audio band gives the best results for me but may not be the case in your system
Had a big grin on my face when I saw this.

Actually, I find this to be true for cathode bypass caps as well.

Quote:
When I asked Benny for the capacitance of the choke, he said he didn't have it, but the resonant frequency was 1 or 2MHz. I couldn't believe this, and asked a transformer winder if it was possible.
Yeah, Benny must have been dreaming.It's just not possible.

Anyway, ringing can be kept under control, I suppose.

John, Brett,

When I meet Benny in a couple of weeks I'll ask for a demo and a copy of some measurements ( I hope) he took.

I'll keep you both posted.

Cheers,
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Old 7th April 2003, 09:40 AM   #13
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Default Re: PARAFEED.

Quote:
Originally posted by fdegrove
John, Brett,

When I meet Benny in a couple of weeks I'll ask for a demo and a copy of some measurements ( I hope) he took.

I'll keep you both posted.

Cheers,
Thanks, but they really should be beta tested in the subtropics in the southern hemisphere, which I'd volunteer to do. Just have him box one up (either version) and send it on down.
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Old 7th April 2003, 10:39 AM   #14
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Brett,

I know you have worked through Lynn Olsen's asylum post on current flows in parafeed connection... Do you have a view on what is the real advantage for parafeed?

Looking at the latest asylum posts on decoupling the cathodes of PP amps to the B+ centre taps - I was wondering if this was similar? I guess I need to do a proper ac large signal analysis of current flows...

ciao

James
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Old 7th April 2003, 12:53 PM   #15
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Brett

You can probably get a parafeed taste without investing in a huge choke by trying a parafeed WOT line stage. Something happens to the mids not to my liking but the bass is nice. Only your ears will be able to tell you if it's right for you. I am currently under a full SET spell induced by a pair of Osram PX25 working hard into my inneficient speakers so my judgement is questionable


cheers

peter
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