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Old 31st October 2007, 04:52 PM   #11
Vix is offline Vix  Yugoslavia
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Default Re: Re: "Circumcising" the F3

Quote:
Originally posted by Babowana
the most important point is to be how the sound would change, IMHO.
I am running ZV9 in the "current mode". I have disconnected Aleph CCS, no feedback. The output is loaded with 10 ohm resistor (it used to be 7.5 ohms , now I changed it to 10) With fullrange speakers, it sounds excellent.

Vix
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Old 31st October 2007, 06:30 PM   #12
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I believe you might have misunderstood what Nelson wrote.

Grey
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Old 31st October 2007, 07:02 PM   #13
Fuling is offline Fuling  Sweden
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Well, Iīm not capable of explaining exactly what I mean (should have paid more attention at the English classes back in school) so letīs drop the whole voltage-current subject.

I guess the only way to find out which CCS configuration that suits me best is to try both.
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Old 1st November 2007, 12:43 AM   #14
flg is offline flg  United States
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Quote:
Originally posted by Fuling
Well, ... I guess the only way to find out which CCS configuration that suits me best is to try both.
As long as you're testing, don't forget just a resistor and more voltage Some woud'nt use a CCS unless absolutly necessary. And then, of coarse, there is the inductor
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Old 1st November 2007, 05:54 AM   #15
Magura is offline Magura  Denmark
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Default Re: "Circumcising" the F3

Quote:
Originally posted by Fuling
Hi

Letīs say Iīm building an F3 amp but I donīt like the Aleph CCS.
Removing R18, R19 and C9 (refering to the ZV9 article) should take care of that, but wouldnīt it also be a good idea to decrease the rail voltage and increase the quiescent current a bit?

F3 operates at 50V (minus some losses in the cap multiplier and cascode circuits) and 2A, perhaps something like 40V and 2,4A would be better in this case?
I agree that the aleph CCS is to be omitted for the Z 9, I took a step back and simply modified a Z 1 to fit the bill. The upper spectre improves, and not so long ago somebody posted measurements that backed this up. The reason it sounds better without the aleph CCS seems to be that the aleph CCS is not adding the same amount current at all frequencies.

I run mine at something like 40V as I recall, and at this point I think it's biased at 3A, this is reasonably reliable.

I have found it to be beneficial to run a few db of global negative feedback, and no local negative feedback.

This setup for this topology, was what I got the most from when using a BOZ pre and Abbey clones with FE166e.


Magura
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Old 1st November 2007, 06:20 AM   #16
Fuling is offline Fuling  Sweden
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flg: I absolutely love the sound of resistor loaded amps, but this time I wonīt use resistors.
I have suitable inductors (112mH 2A) but Iīll save them for another day.

Magura: Now weīre talking!
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Old 1st November 2007, 02:11 PM   #17
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Default Re: Re: Re: "Circumcising" the F3

Quote:
Originally posted by Vix

With fullrange speakers, it sounds excellent.

Nothing is atrange.
Excuse me, which flag state . . . blue/white/red . . . ?
I was sleeping in world history class room.


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Old 1st November 2007, 03:20 PM   #18
Vix is offline Vix  Yugoslavia
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Default Re: Re: Re: Re: "Circumcising" the F3

Quote:
Originally posted by Babowana

Excuse me, which flag state . . . blue/white/red . . . ?
Almost as Choky's

It is strange and complicated. I live in Kosovo (ex-Yugoslavian/Serbian Province). It is now administered by United Nations. As it doesn't have its own flag, I put the one you see...

Btw, I don't like politics nor politicians. We'd be much better off if they listened to music instead of doing what they do: :bs:

Back to the topic...I was surprised that so few people (anyone?) runs the ZV9 without feedback, i.e. as a transconductance amplifier. It sounds as a cross between a "normal" ZV9 and an F2. Actually more like F2, but better.

Regards,

Vix
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Old 1st November 2007, 04:15 PM   #19
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Default Re: Re: "Circumcising" the F3

Quote:
Originally posted by Magura


I agree that the aleph CCS is to be omitted for the Z 9, I took a step back and simply modified a Z 1 to fit the bill. The upper spectre improves, and not so long ago somebody posted measurements that backed this up. The reason it sounds better without the aleph CCS seems to be that the aleph CCS is not adding the same amount current at all frequencies.

I run mine at something like 40V as I recall, and at this point I think it's biased at 3A, this is reasonably reliable.

I have found it to be beneficial to run a few db of global negative feedback, and no local negative feedback.

This setup for this topology, was what I got the most from when using a BOZ pre and Abbey clones with FE166e.

Magura
I run something very similar to this with input buffer and a CLC PSU and results are just as good, though different lineamp, in this case toobs.
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Old 1st November 2007, 04:39 PM   #20
flg is offline flg  United States
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Default Re: Re: Re: Re: Re: "Circumcising" the F3

Quote:
Originally posted by Babowana
... which flag state . . . blue/white/red . . . ?
I was sleeping in world history class room.
Red,White,Blue?
Quote:
Originally posted by Vix
...Btw, I don't like politics nor politicians. We'd be much better off if they listened to music instead of doing what they do: :bs:
Vix
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