Harman Kardon HD7525 DAC concept ?

[Bernhard]

Hi,

anybody knows what is done in this player, got 4 x PCM61 and a bunch of 74HC164 after os filter.

[rfbrw]

macrovision? DD/DTS?

[guido]

nope,

That's the entry model with RLS: real-time linear smoothing.

http://www.diyaudio.com/forums/showt...970#post495970

Sorry for the typo, that's probably why you did not find it with search (you searched, didn't you

The rest of the info is in that tread. Never seen one, only have the brochure..

edit: and forget about the claims on my own dac, found out later it did not work as i thought it did

[Bernhard]

Originally posted by guido

That's the entry model with RLS: real-time linear smoothing.

Now how to 'translate' the above into a schematic? The above text implies the use of an integrator, but then why 2 dacs/channel?

As I got the player I can follow the traces and draw a schematic.

I was thinking that maybe the logic chips will translate the data into positive and negative halfwaves, but this hardware double oversampling is interesting too.

[wimms]

As I got the player I can follow the traces and draw a schematic.

Please do.

I *suppose* that it is roughly something along these lines.

[jean-paul]

If you want it, I have the service manual ( of course ) of HD7725 with the same output stage/DACs.

[Bernhard]

Yes, I want it, please email to me.
hd7525atbeautyphoto.de

[JohnW]

Hi Jean Paul,

Could you Pls. also Email me a copy of the HK "oversampling" DAC section.

Cheers,

John

[rfbrw]

Originally posted by guido

edit: and forget about the claims on my own dac, found out later it did not work as i thought it did

have you corrected it?

[JohnW]

Hi Bernhard,

"Even if it is a rubidium atomic clock, that does not necessarily mean it is low jitter"

As a quick side note, the lowest phase noise atomic clock I'm aware of is the Stanford Research Systems Rubidium Frequency standard PRS10.

I use one phase locked to my 2 FTS4050 Cesium Frequency standards to reduce their “short-term” phase noise – on my module its phase noise is better then -140dB @ 10MHz 10Hz offset!

John