The "mod your Zhalou" Thread

[keyid]

going to try this.
Also read on diyaudio this would work too. Digikey - Newava S22160.
So on these pulse transformers only 4 pins are used and just have to connect the signal that goes in and comes out, and they are non polar so it doesnt matter which set is in and out.

Any recommendation for the powersupply opamp? I been using 2604 and recently replaced with AD823. The sound has changed quite a bit. Probably going to try OP275.

 

[FOXY]

Hi,
I have Zhaolu 2.5A, and need help how to improve the sound of this DAC.

Already have:
-replaced op-amps with LM4562.
-bypass the input caps.

What more mods will improve the sound of this DAC?

 

[BobMcN]

uhhhh, read the thread perhaps?

 

[Pars]

Quote:

Originally Posted by BobMcN /img/forum/go_quote.gif uhhhh, read the thread perhaps?

And, uhhh, read the thread on diyaudio which it appears you also posted the same thing to...

 

[Bleemv1]

hey guys,

I want to add an extra line out from the dac. Can I just connect the wires up to the current line out jacks? or should I go from the board?

thanks

 

[sleep888]

I have a question for quite a while, and I search the mail trial about Zhaolu for answer, but cannot find ... ...

It seems that no one complain Zhaolu do not have Anti-jittering unit, why? I assume anti-jittering module is critical part for a DAC which always be used for some pchifi source.

Am I wrong? Thanks ...

 

[rolleiman59]

Hi Gang,
I am having fun moding my D2.5A DAC. So far I have done the following:
- Bypassed the two ouput caps
- Disconnected the Headamp completly
- Removed ouptut jacks from the PC board and install a set of gold placed jacks on the line out.
- Replaced the OP amps with LME49720s
- Removed PC RCA jack and installed gold plated one
- Installed a 673-PE-65612 pulse transformer (+RCA, -RCA on primary then connected Secondary to + side and ground of PC board)
I read (and can not find the posting) where someone separated the ribbon cables connecting the boards and twisted some and re-routed others)
Does anyone have pinouts of the connectors for the boards in the D2.5A DAC that they could post or send me. Also, are schematics of the boards available?
Thanks!

 

[BobMcN]

For the zapfilterers using a 2.5C - are you getting any bleedthrough on your RCA outputs? When my preamp is muted and a CD playing I am hearing music coming through the speakers. This didn't happen before and doesn't happen on any other component.

I did measure about .2mv Left and .9mv Right DC on the RCA's. Not sure how to eliminate that or if it is causing the issue.

Any thoughts?

thanks,
Bob

 

[udo]

Where (in Europe) can I get the small S/DPIF 'transformer' for the D2.5C?
It's for properly decoupling the signal.


[size=xx-small]As I posted in a different thread I will mod the clock of the NAD C521BEE transport with a D-clock.
What could be next for this setup?

NAD C521BEE w/ D-clock -> D2.5C w/ Zapfilter 2 and improved clock -> C320BEE -> Tannoy F3

Thought about Zapfilter for C521 but wondering about muting transistors etc.

Maybe a good S/PDIF switchbox that works at 96/192KHz?[/size]

 

[udo]

Quote:

Originally Posted by BobMcN /img/forum/go_quote.gif For the zapfilterers using a 2.5C - are you getting any bleedthrough on your RCA outputs? When my preamp is muted and a CD playing I am hearing music coming through the speakers. This didn't happen before and doesn't happen on any other component. Any thoughts?

Do you notice that the Zapfiltered d2.5C is quite loud compared to the other sources?
Does the 'mute' not just mute but attenuate a certain amount of dB's?
This could explain your issue. Just move the D2.5C to a different input, the problem will move as well.

 

[BobMcN]

I've got an answer from LC Audio (it would have been nice to have this in the Zapfilter instructions instead of leaving it up to the user to find out though) ...

I've connected the + Zap board output to the + on the RCA.
the - on the Zap board to the ground (-) on the RCA

Apparently I need to connect the ground on the Zap board to the ground (-) on the RCA.

I think that will eliminate the DC and the bleed through.

Again, would have been nice to have this simple diagram or description i the instructions.

Thanks,
Bob

 

[udo]

What PSU can I use to replace the D2.5C standard PSU?
I zapfiltered the Zhaolu so the PSU only needs to power the DAC board, not the analog board.
I would like to place a slightly overdimensioned, but physically smaller PSU in the place of the standard PSU board.

This could give room for the Zapfilter and a dedicated clock to be installed.


Or maybe just combine ourselves:

- Dedicated Clock (D-clock/XO3/Tentlabs,etc)
- DAC board (Zhaolu, other?)
- Zapfilter
- Dedicated power for the DAC board since clock and zapfilter have own supply

Any ideas, tips etc?

 

[BobMcN]

A dedicated clock is more aptly installed in the transport, not the DAC. That's where you'll get more bang for the buck.

Bob

 

[udo]

That is an operation in progress.
I posted a thread about adding a D-clock to the NAD C521BEE.
No responses so far.
Why does the transport clock matter most?
What is the relation between DAC and transport clocks?

I know the transport encodes the S/PDIF stream and thus a clock, but doesn't the DAC reclock some way?
Or what else?

 

[ddeell72]

Many are expecting D 3.5 ...... expecting ....