Best Sonos ZP-80 Mod?

Has anyone tried the Emperical Mod, it's more money and he really knows what he is doing. Perhaps even more than Cullen, in that the digital domain is his main focus.

Does anyone have experience comparing the Cullen modded ZP80 through a quality DAC with the regular Slim Squeezebox 3 or transporter.

I have both the Sonos system and SB3, as well as 3 high quality DACs (Lavry DA10, Naim Supernait and Resolution Audio Opus 21......the latter two of which have built in DACs which can be accessed by digital sources)

Comparing the digital outs of the basic SB3 to the basic ZP80, the SB3 is far superior.....less congested, less compressed, better soundstage and instrument separation.

I do like the convenience of the Sonos system though. If I am to spring $500+ to get the Cullen mods, I would hope I would be getting a significant upgrade from the SB3 quality and close to the Opus 21 CD player quality.

Quite a specific scenario, I know, but does anyone have any insight to answer these questions?

Thanks, Nigel

http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1204503359&openflup&9&4#9

http://www.audiocircle.com/circles/index.php?topic=42526.30

http://www.audiocircle.com/circles/index.php?topic=47245.new#new

Is a basic difference between the Empirical and Cullen mods is that in the Empirical mod the reclocker is an external unit (pace-car), where in the Cullen mod the reclocker is a board which replaces a board inside the ZP-80?

"Is a basic difference between the Empirical and Cullen mods is that in the Empirical mod the reclocker is an external unit (pace-car), where in the Cullen mod the reclocker is a board which replaces a board inside the ZP-80?"

No, there is HUGE difference between the Cullen reclocker and my Pace-Car. The Cullen is an asynchronous sample-rate converter (ASRC) with a better oscillator than the stock Sonos. This is just like an upsampling DAC or a Monarchy DIP. It will improve the jitter by resampling the data, but nothing like the Pace-Car, which does not change the data.

The Pace-Car is a true reclocker with a FIFO memory that is clocked by a Superclock4. It offers superior isolation, jitter rejection and superior clock. It does not resample the data stream like the Cullen reclocker. The Pace-Car also has a separate power supply from the Sonos and many voltage regulators. It contains probably 30X the parts count as the Cullen board, even more parts than a typical DAC. This is a very complex circuit and designed to test equipment standards, using GHz coaxial cable and connectors. It can also drive I2S input DAC's directly, as well as standard DAC's using S/PDIF or AES/EBU. The jitter levels from the Pace-Car will be lower than ANY CD transport. The Pace-Car was recently compared in a shootout (I was not present) to 2 new Meridian $8K and $14K CD players and there was no contest. The participants told me that the Pace-Car was clearly better at a fraction of the price. I believe it was driven in this case by an Apple TV and an AirPort Express, but can be driven by virtually any PCM digital source.

Steve N.
Empirical Audio