Hello!
I am rebuild the vintage Philips 14 bits CD player by using Borbely all FET IV stage aS the attached circuit shown.
Anyone can give me a suggestion which buffer should be following this IV stage?
I see something called diamond buffer stage. Is that any good??
Thanks!
I am rebuild the vintage Philips 14 bits CD player by using Borbely all FET IV stage aS the attached circuit shown.
Anyone can give me a suggestion which buffer should be following this IV stage?
I see something called diamond buffer stage. Is that any good??
Thanks!
Attachments
Diamond buffer is good yeah but not as good as a classA SE buffer. Why use classAB on small signal stages when classA doesn't incur much heat penalty?
The Neurochrome Universal Buffer has opamp on it but my friend suggests all opamp replace with Burson SS Opamp V6 for better result.
You probably won't get the lowest possible distortion out of a discrete I/V stage (ICs normally do better) so I take it from that choice that lowest distortion isn't the primary aim. So it would seem a discrete buffer was more in keeping with your apparent philosophy.
I reckon just a simple pair of JFETs like Nelson uses in his Pass B1 buffer preamp. Simple is best and you already have JFETs in your I/V stage.
Diyaudio store has something similar but backorder :-(
https://diyaudiostore.com/products/mezmerize-b1-buffer?variant=5939090628
https://diyaudiostore.com/products/mezmerize-b1-buffer?variant=5939090628
Unless you need to place a fantastically low impedance filter after that iv thing there's most probably no need for another buffer...the real question is what type of filter you're going to use if any.
My friend sent me this link.
https://tortugaaudio.com/products/diy-preamp-components/sspb-v2-solid-state-preamp-buffer-board-kit/
https://tortugaaudio.com/products/diy-preamp-components/sspb-v2-solid-state-preamp-buffer-board-kit/
the schematic shows heatsinks on the output MOSFET's, so impedance is probably low enough to drive shorter interconnects and a pre-amp input stage from the LPF output directly, assuming the DAC chip isn't being operated at 1x (e.. 44.1k) sample rate, but instead has an upsampler /digital filter at 4x or 8x before the DAC chip. If there is no upsampler / digital filter chip, then you'll need a 6th order or higher LPF after the DAC chip, which is more appropriate for implementation using multiple active LPF stages using high quality op-amps
I don't see any source degeneration resistors on the output MOSFET's, so be careful setting the output bias current so it doesn't run away.
Between line output transformer and First Watt B1 buffer, which one is more adequate after the Borbely all FET IV stage??
stock op amps for TDA1540 partial schematic shown look to be NE5534. is your CD player LHH2000? note that if attempting to remove all op-amps and replace with Borberly IV stage, you will lose the De-emphasis function necessary for playback of some CD's (esp those mastered in 1980's and 1990's using pre-emphasis)
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