Balanced audio technology VK500/1000: "Single-Ended Bridge" Topology, 450W into 4 Ohm
About
http://www.balanced.com/resources/brochures/1998/VK500desc.pdf
I read:
A typical solid-state amplifier
will have four or five gain stages, with a feedback loop traversing these same
stages to correct the signal. The VK-500 uses only two gain stages—without
global feedback. Unusually direct for any amplifier, this purist signal path is even
more surprising in a design of such high power. The ingenuity of the signal
path is complemented by a unique single-ended bridge topology that allows the
use of superior N-channel MOSFETs in both driver and output stages. The
result is a clear, open sound that breathes life into music.
This sounds like a design from Mr. Nelson Pass.
Also the review about
Balanced Audio Technology VK-500 Reviews
and
Product Review
Perhaps a transition from a "ZEN"-topology to a "CSPP" (Circlotron)??
Who knows more about BAT's topology?
About
http://www.balanced.com/resources/brochures/1998/VK500desc.pdf
I read:
A typical solid-state amplifier
will have four or five gain stages, with a feedback loop traversing these same
stages to correct the signal. The VK-500 uses only two gain stages—without
global feedback. Unusually direct for any amplifier, this purist signal path is even
more surprising in a design of such high power. The ingenuity of the signal
path is complemented by a unique single-ended bridge topology that allows the
use of superior N-channel MOSFETs in both driver and output stages. The
result is a clear, open sound that breathes life into music.
This sounds like a design from Mr. Nelson Pass.
Also the review about
Balanced Audio Technology VK-500 Reviews
and
Product Review
Perhaps a transition from a "ZEN"-topology to a "CSPP" (Circlotron)??
Who knows more about BAT's topology?
Attachments
Last edited:
I don't need a detailled schematic diagram, only a simlified schematic like that one from the Pass Aleph on page 5 aboutlike krell, they don't release schematics. good luck!
http://peufeu.free.fr/audio/schemas/Pass_Aleph_3.pdf
The phrase "balanced single-ended", first used IIRC by Bel Canto, and an
oxymoron if there ever was one, is nevertheless pretty descriptive.
It is likely:
1) Circlotron, either Common-Drain or Common-Source.
2) Two conventional single-ended output stages operated in balanced mode,
either Common-Drain or Common-Source, biased by a CCS or variable
current source.
3) If the product is advertised as lacking global feedback, then it very likely
is a Common-Drain version of 1 or 2
(Fet pin references. Your pins may vary)
oxymoron if there ever was one, is nevertheless pretty descriptive.
It is likely:
1) Circlotron, either Common-Drain or Common-Source.
2) Two conventional single-ended output stages operated in balanced mode,
either Common-Drain or Common-Source, biased by a CCS or variable
current source.
3) If the product is advertised as lacking global feedback, then it very likely
is a Common-Drain version of 1 or 2
(Fet pin references. Your pins may vary)
in post #3 under
https://www.diyaudio.com/community/threads/bat-vk-500-schematics-info.203650/
was an URL with schematic - unfortunately this file in the URL is deleted in the meantime.
Who have save the schematic ?
Here an URL with pics of a dismantling procedure:
https://www.stereonet.com/forums/topic/238057-balanced-audio-technology-vk500-repair/
In the attachment some images.
At first glance you can see numerous N-CH MOSFETs in parallel mode operation, but no associated source resistors.
https://www.diyaudio.com/community/threads/bat-vk-500-schematics-info.203650/
was an URL with schematic - unfortunately this file in the URL is deleted in the meantime.
Who have save the schematic ?
Here an URL with pics of a dismantling procedure:
https://www.stereonet.com/forums/topic/238057-balanced-audio-technology-vk500-repair/
In the attachment some images.
At first glance you can see numerous N-CH MOSFETs in parallel mode operation, but no associated source resistors.
Attachments
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