[bhobba]

Hi Bob, Karsten, and All

In preparation for getting my new Mini I have been looking at what CD player to use.  Intitally I thought of a modded squeezebox.  Recently I came across the new Anagram based system from Cambridge Audio - the 740C and 840C.  I have been interested in the anagram technology for quite some time now, and on a technical level believe it offers current state of the art playback quality.  As part of researching it I came across an old post of Kartens on the Mundorf upgrade where he was enthusiastic about the anagram sonic 2 being fed by a computer.  I guess the query is, is he still impressed with it?  I was thinking of getting the players modded with better power supplies and lower jitter clock etc.
Does he (or anyone else with a view) think a good choice is CA's CDP's, with a view of using them purely as a DAC later, and connecting them to computer? 

Thanks
Bill

[Karsten]

Hi Bill,

Yes I still prefer using a PC as digital source, however latest findings are not in favour of laptops, at least not the laptops I have tested (4 pcs). They are all heavily beaten by a stationary Medion MD8828.

The most plausible course is that it is related to jitter. Laptops have to comply to FCC class A regulations where stationary only has to pass FCC class B. This means that spread spectrum clock is more intensively used on laptops, which could be one explanation. It could also be that the USB clock on the stationery simply is better. Well I'm still looking into this issue trying to figure out why.

I really like the digital attenuation in Windows Vista, it beats every preamp I have tested. When my own Sonic2 DAC design, featuring digital attenuation, is ready I will test some low power computers running Linux as well. The modern laptops did not really benefit from Linux, the stationary running Vista still beat the crap out of them.

Regards,
Karsten

[JP78]

bhobba,

what will your future player be plugging into in terms of a preamplifier (or direct to the amplifier)?  the effects of  impedance matching / current output compatability of your player with your preamplifier are very important in my humble opinion...you should make sure whatever player you decide on should have the right impedance and output voltage to match your pre...otherwise what sounds great with one system may be totally lifeless with yours.

good luck!

jp

[bhobba]

Hi Karsten

Yes I still prefer using a PC as digital source, however latest findings are not in favour of laptops, at least not the laptops I have tested (4 pcs). They are all heavily beaten by a stationary Medion MD8828.

Thanks for the skinny

The most plausible course is that it is related to jitter. Laptops have to comply to FCC class A regulations where stationary only has to pass FCC class B. This means that spread spectrum clock is more intensively used on laptops, which could be one explanation. It could also be that the USB clock on the stationery simply is better. Well I'm still looking into this issue trying to figure out why.

I look forward to your findings.  Please keep us updated.

When my own Sonic2 DAC design, featuring digital attenuation, is ready I will test some low power computers running Linux as well. The modern laptops did not really benefit from Linux, the stationary running Vista still beat the crap out of them.

Now that sounds like the DAC for me.  What may be my best option at this stage is to get an interim DAC until your design is ready - something cheap.  I will do a bit of research on that.

Thanks
Bill

[bhobba]

Hi JP

what will your future player be plugging into in terms of a preamplifier (or direct to the amplifier)? 

A Burson P-100.

the effects of  impedance matching / current output compatibility of your player with your preamplifier are very important in my humble opinion...you should make sure whatever player you decide on should have the right impedance and output voltage to match your pre...otherwise what sounds great with one system may be totally lifeless with yours.

Thanks for info.  That is the exact reason I chose a Burson.  It is basically an upgrade on the famous Burson buffer than many have commented on improve things when inserted between a DAC/CDP and an amp.  The other advantage is it has a bypass mode input so I can handle sources other than using a PC and its volume control.  That way I can still listen to sources like my Foxtel which don't go through a PC.  Only problem I see is later I may need two pass throughs - one for my PC as a source and one for a home theatre processor.  A technician will probably be able to do an easy mod to overcome this when the time comes.

Thanks
Bill   

[gongos]

I use my PC for audio playback w/ my Revelations and would never go back to a CD player. I have a Empirical Audio modified Squeezebox w/ Steve's Pace-Car feeding a Turbomodded Northstar 192 DAC. With my setup the quality of the PC is irrelevant--all the PC does is transfer data to the Squeezebox. You want to talk about lack of jitter--that's Steve Nugent's obsession. All I have now is amazing dynamics, instrument seperation, detail, and a one of a kind musical experience everytime I listen to a album.

[bhobba]

I use my PC for audio playback w/ my Revelations and would never go back to a CD player. I have a Empirical Audio modified Squeezebox w/ Steve's Pace-Car feeding a Turbomodded Northstar 192 DAC. With my setup the quality of the PC is irrelevant--all the PC does is transfer data to the Squeezebox. You want to talk about lack of jitter--that's Steve Nugent's obsession. All I have now is amazing dynamics, instrument seperation, detail, and a one of a kind musical experience everytime I listen to a album.

Definitely a route I am considering over an audio PC.  Do you use the digital volume of the squeezebox?

I must admit to being really in love with the anagram technology.  Maybe even makes I2S redundant.  When Manly, (for example - others found exactly the same), was testing it they tried all sorts of things to 'spoof' the jitter.  Nothing worked - it was always, without exception, exactly the jitter of the clock in the DAC.

I have been looking into an interim cheap DAC.  Here in Australia a 740C can be had for about 1K via eBay, so is not much more expensive than even a cheap DAC, and you get a reasonable transport thrown in for free.   

Once my money issues are sorted out, it would be very interesting testing a pacecar modified squeezebox feeding it.  My guess is it will be exactly as Manly found - but you never know - which is why it would be so interesting.

It would be nice however if the DAC Karsten is working on would accept I2S.  A pacecared I2S squeezebox into a Sonic 2 DAC with an Anagram timelock (reputed to the lowest jitter clock currently available) really would be something.  Something a techie nerd type like me would just love.   

Thanks
Bill

[gongos]

I don't use the volume control on the SB. Still looking for the perfect preamp. I should give it a try.

[bhobba]

I don't use the volume control on the SB. Still looking for the perfect preamp. I should give it a try.

The Burson looks good.

Thanks
Bill

[gongos]

I don't use the volume control on the SB. Still looking for the perfect preamp. I should give it a try.

The Burson looks good.

Thanks
Bill

Looks good for what? Using with the SB direct to amps?

[bhobba]

Looks good for what? Using with the SB direct to amps?

Both - it has straight through and volume controlled.  That seems to be the beauty of it.  Being basically an upgraded Burson buffer it has a dual purpose - both as a volume control, selector and buffer.  The only change I would think about is replacing the alps pot with either a ceramat or stepped attenuator.

Thanks
Bill

[Karsten]

It would be nice however if the DAC Karsten is working on would accept I2S.  A pacecared I2S squeezebox into a Sonic 2 DAC with an Anagram timelock (reputed to the lowest jitter clock currently available) really would be something.  Something a techie nerd type like me would just love.   

Thanks
Bill

My DAC design does accept I2S, although through an experimental connector.

Regards,
Karsten

[bhobba]

Hi Karsten

My DAC design does accept I2S, although through an experimental connector.

Thanks for the info - I really appreciate it.  The more I think about it the more your DAC appeals - even without an I2S connection.  I am not 100% convinced with the excellent jitter performance of the Anagram up-sampling any audible difference would exist.  What do your investigations show?

Can you post some details of your DAC eg estimated cost, availability, inputs etc?.  After thinking about it, your design with its ability to eliminate the cost of a preamp, is looking better and better.  I really like listening to Foxtel radio which has a toslink out - so a toslink input would be nice - but not necessary as converters are readily available.

Thanks
Bill

[Karsten]

Bill, I'll get back to you on this one tomorrow. Having quite a bit of jitter myself 

Happy New Year to all!

Karsten

[bhobba]

Bill, I'll get back to you on this one tomorrow. Having quite a bit of jitter myself 

No problemo - take your time.  Just to clarify - I was thinking in terms of the Steve Nugent pacecared SB3 which has either an I2S or SPDIF output - the SPF output has a slight extra bit of jitter as compared to the I2S.  It is that level of jitter difference I was thinking of.  Although I trust the guys that tried to spoof the jitter of Anagram DAC I am not aesthetically happy with the 'crud' that comes out an unmodified squeezebox and suspect it would cause problems.  A basic pacecar, without a superclock, feeding a SPDIF seems plenty good enough to allow the anagram technology to do its thing free of grunge.

Happy New Year to all!

Right back at ya - Happy new year - not only to Karsten but to everyone.

Thanks
Bill

[RodMCV]

Happy New Year to all the SP-Tech family.

Karsten,

What is your opinion and experience on the sonic difference
 and required break-in time on the different
levels of Mundorf Crossovers for the Revelations?

Thanks,
Rod

[Karsten]

Bill,

As promised, hereby some more information about the DAC. First of all the brand name will be Blue Cheese Audio and the model name is Roquefort. ( )

Input:

2x AES/EBU
2x S/P DIF
1x COAX
1x Toslink
1x USB
I2S/PCM via experimental connector.

Output:

1x RCA
1x XLR

Remote controlled input selection & digital attenuation in 0.5 dB steps. Remote control will only have one button, which is a small joystick.

Analogue output module is situated on a piggy back module and upgradeable. 3 versions are being prepared. Version 1 is op amp based I/V conversion and buffer. Version 2 is with discrete build I/V conversion and op amp based buffer. Version 3 is with discrete build I/V conversion and class A zero feed back buffer.

The clock oscillator is a TCXO from Connor Winfield - with very good phase noise performances.

The design will comply to the max. 1W standby consumption, although most will probably prefer to leave it on all the time.

Physical size is similar to the 1U 19" rack size, however faceplate for rack mounting is optional.

I'm still waiting for the real prototype boards to show up, so I can't say exactly how jitter immune this design is yet. However the Anagram designs I have tested in the past does seem to benefit from a good transport, but less critical than other DAC designs I have tested.

Estimated introduction price is 6k USD.

Regards,
Karsten

[Karsten]

Happy New Year to all the SP-Tech family.

Karsten,

What is your opinion and experience on the sonic difference
 and required break-in time on the different
levels of Mundorf Crossovers for the Revelations?

Thanks,
Rod

Rod,

The perceived difference of the standard and ultimate cross over depends a lot on the front end used. The ultimate does allow higher resolution and better micro dynamics. With a really clean and fast front end, the ultimate cross over will sound a lot sweeter and more natural compared to the the standard which can be slightly "edgy" if pushed beyond it's limits.

The ultimate cross over can take quite a while to settle in, at least several hundred hours. However I think it sounds pretty good already after a couple of hundred hours.

Regards,
Karsten

[bhobba]

Hi Karsten

Estimated introduction price is 6k USD.

Thanks very much for the info.  It is greatly appreciated.

Unfortunately at this stage 6K is a bit beyond my budget - when I get my super in about 2 years time - that will be another matter.  To others reading this I want to add, considering what went into it, I believe it is a bargain - it is just a probelm with my fiances at the moment.

Thanks
Bill

[mcullinan]

Karsten,
6K... is that the same 6K that is 4 more than 2? Aaaargh! You are making me resort to a life of crime?
Ok I hope you can live with that heavy burden.. hehe
Mike