USB to I2S 384Khz - DSD Converter

[glt]

Originally Posted by NicMac

Ok. Back on topic
Found something in my incoming post today........

NicMac, Do you know why "MUTE" in your boards is been painted over?

[kevinkr]

Just added myself to the list for two.. Building a new dac or two in the near future.

[NicMac]

Originally Posted by glt

NicMac, Do you know why "MUTE" in your boards is been painted over?

No. Maybe Domenico can enlighten us....

[amanero]

Mute signal has been reassigned to Pin 11 and Pin 6 now is MCLK (master clock )

http://www.amanero.com/drivers/combo384-D.pdf

[gentlevoice]

@kevinkr:

Just added myself to the list for two.. Building a new dac or two in the near future.

Bruno Putzeys of Hypex amplifiers has suggested a fast CMOS flip-flop as a DAC for one-bit signals ...

@rayCtech: Thanks for outlining your approach to designing a discrete DAC in one of the previous posts. The theory behind this is beyond my understanding, however, I wonder how it's possible - to a large extent - to genuinely "expand" on the original information available in e.g. a 2.8 MHz one bit signal? I reckon that even if some aspects of the original signal can be changed/altered/improved there's still "only" 2.8 MHz 1 bits available ...?

Greetings,

Jesper

[gentlevoice]

P.S.: Any of you know of a DAC that converts 44.1 - 384 kHz/24 bits and also 128fs direct DSD (i.e. without multibit conversion etc.)? Preferably a DIY project ...

Greetings,

Jesper

[RayCtech]

Originally Posted by gentlevoice

Bruno Putzeys of Hypex amplifiers has suggested a fast CMOS flip-flop as a DAC for one-bit signals ...

A much better approach would be a ECL flip-flop with TTL in and balanced ECL out...

The rail to rail and class B / D type of clipping and "sticking" to ground and the PSU rail and high frequency generation will be exchanged with class A performance and controlled voltage swing.

Originally Posted by gentlevoice

I wonder how it's possible - to a large extent - to genuinely "expand" on the original information available in e.g. a 2.8 MHz one bit signal? I reckon that even if some aspects of the original signal can be changed/altered/improved there's still "only" 2.8 MHz 1 bits available ...?

I have a website under construction and there will be more informations in the technology section and in the white papers there.

[Bunpei]

Originally Posted by qusp

doesnt really sound like the DSD direct filter is ..you you say....'optimal'?

then again it was hard going even with chrome translator, it did seem to be a theme among thos he tried with the LPF compared to using ESS DSD mode

As far as I know, more than ten people in Japan tried their own "easy LPF" methods to play DSD raw signals without DAC because two DSD64,128,256 compatible transports, Chiaki's SDTrans and ElectrArt's USB Dual Audio are popular among them. Some try a single LCR, other try line tranformers & load resistors other than a single R. No one say "It is optimal" as they suffer residual digital noises that is hard to be eliminated completely. However, most of they say "more vivid or fresh with enough resolution than expected".

The author of the blog page says, Amanero Combo384 is a suitable platform of high cost performance and good availability to experiment such a DSD "playing". His usual DAC is not ESS-based one but FN-1242A(by Japanese manufacturer)-based one.

[Bunpei]

Originally Posted by qusp

..... with the USB board being usb powered this would mean USB ground passed right through… thats what you call terrible PSRR ...

The reason why the author of the blog page tried a various bypass capacitors was that the behavior of residual noises was variable depending on USB cabling methods. I think his finding may mean your worries.

[Bunpei]

Originally Posted by gentlevoice

Any of you know of a DAC that converts 44.1 - 384 kHz/24 bits and also 128fs direct DSD (i.e. without multibit conversion etc.)?

Do you mean, even for DA conversion of PCM you want not multi-bit but 1-bit delta-sigma modulator?
If so, I'm afraid no modern commercial DAC chips satisfy your requirement.

If you allow a multi-bit delta-sigma modulation for PCM, TI BB DSD1794A(and its family models) may meet your conditions because only analog filter is applied to DSD input signals under their "Advanced Segments" architecture. DSD1794A supports DSD64, DSD128 & DSD256.