New digital front end

I have only heard the Sim Moon Eclipse as part of a complete Sim system set-up so can't comment on it's good or bad points.

However, I have heard the CEC combo on two occassions and can say that it is an impressive performer for the price. I think the DX-71 is now in it's MkII form and also contains a pre-amp section. The sound is very liquid or should I say organic (reviewer speak) and that is something that cannot be said for many solid state CDPs near the CEC combo's price point. In the past, there had been several questions raised over the reliability of CEC's belt-driven transports. Some blamed it on the fact that the very nature of belt-driven transports meant that they were more susceptible to developing problems. However, the likes of Burmester of Germany are able to utilize belt-driven transports in some of their CDPs with no reliability issues so in the case of CEC, it was just a case of bad quality control at the point of manufacture. However, these quality control issues have now been largely overcome especially with the latest models.

As to the issue of delta/sigma bitstream etc, well I have heard CEC components several times and they've never failed to impress these ears and IMO, if the price is right and the sounds seduce, then the underlying technology pails into insignificance from my perspective. In other words, I believe that the musical message is more important. Personally, I think you should place them head to head although I think that the Eclipse, at it's new price, is significantly more expensive than the CEC combo but I would think that the Eclipse could be purchased second-hand or ex-demo where you are if it's sound appeals. Good luck!



Enjoy the music,

Lawrie.

 

Read my post Tone - he's selling his DAC64 He now reckons it's harsh sounding - well, with beryllium speakers, what do you expect

Michael.

 

You see, I'm so non plussed with stuff these days, I fall asleep reading the threads, sorry !!!
The Sim is a nice player (and tweeks well), has grove/interest/detail & image, plus a serious bling factor.
The opus 21 I don't rate, however lots of people do, so worth a listen.
Why not just change the dac?, a A/S discrete with built in pre & b/g version is available used for around £3k, or a wadia 27ix dac, if your feeling desperate and want to go all ultra-fi then a delius/elgar?, or maybe a Meitner?
That harmonix dax thing remo?, hum with 18 bit philips chips, sorry again I thought it average, just different, but not better twist on whats about nothing more. (Hype factor 5)
AS for B/Stream V's Delta sigma, well, personally I just use me ears, if its right you'll know, if not keep you cash rooted in your sky rocket.
BTW if you like the essence of the dac 64, you can make it sound good, it is possible. Wm
#

 

The 2.89GHz thing is fine in theory, and I ran up against this in some early thought processes I had on PCM -> PWM conversion.

However, that's only the case using very simplistic logic. By using noise shaping, you can decrease the required clock rate to only a few MHz whilst retaining the full resolution of CD (or even rather more).

In terms of technology, it would be entirely possible to make a DAC chip running at 2.89GHz. We can make a 60 million transistor computer processor run at 4GHz, so a simple (by comparison) DAC is easy. There is simply no need for it however.

 

[as for what makes a cdp / dac sound good - for me i've always felt that the power supplies / analog output stage had just as much - if not more influence on the sound.]

Julian,

You are absolutely right. The small currents output from a multibit DAC ladder, like the BurrBrown PCM1704 found in the Eclipse, require conversion to voltage for later filtering and amplification. One of the design challenges with the 1704 is how to convert its current output into a clean voltage. For the 1704 this is very difficult due to HF noise on its output. The raw current carries higher order multiples of the sampling frequency and higher "images" of the audio signal.

That's the reason why power supply noise is so important in any digital audio system and more so with multibit DACs. (The use of a switched power supply for the DAC64 really isn't a great idea in first place, and can explain a lot of things...)

[AS for B/Stream V's Delta sigma, well, personally I just use me ears, if its right you'll know, if not keep you cash rooted in your sky rocket.]

Wm,

May I ask then why Wadia's older models sound better to you?

[BTW if you like the essence of the dac 64, you can make it sound good, it is possible. Wm]

Like I said, "in the end all comes down to the technical implementations". The DAC64 is nothing but WOW factor... like so many other things in audio. And I've been using my ears, trust me. Unfortunateley not with the rigth equipment though... Oh mighty beryllium that your dust can rest upon us as we've been deaf for so long!

Merlin,

How do you campare the Opus21 and the Eclipse?

 

The Opus 21 doesn't sound right at all. Honestly it sounds very strange to a lot of people. Until that is they find themselves really enjoying their music, then they are hooked on the sound.

The Eclipse does everything a high end player should IMO -it's clean, not forced in any way, very detailed, and the latter units (post HDCD) are dynamic.

It's just the Opus does something - you'll have to listen to see if it's for you. Interestingly the two machines use very similar dac topologies, along with sperate psu's. They do however sound quite different to my ears.

 

BD,

You just answered your own question to me in your first paragraph the 1704 dac chip, though it can be over come by the use of total reverse isolation power suppiles, for both analogue and digital segrigation.
The 64, does required the removal of the swps & analogue stage reworking along with clock screen work, it does then becomes acceptable.
Though we actually do take em apart & investigate rather than theorise too much.
Implementation is always the key, though yet to date, very few have got it right.
We first listen at great length to a player to first assertain weather or not it has postive attributes that will 'do the job' before we comence surgery.
The older Wadia's to my mind are far more musical & have that flow, the newer ones don't, granted they' arn't as detailed initialy though this can be fixed.
The present a sound that is believebly tangable with very strong image focus & proper lower frequency reconstruction and they are involving & have an analogue style flow to them.
PMC 63K's and the 1702's to my mind coupled with the first generation 24 bit resolution enhancement chips, give that something I've yet to here in anything lately.
They provide a good starting block to which to build a decent sound.

 

[However, that's only the case using very simplistic logic. By using noise shaping, you can decrease the required clock rate to only a few MHz whilst retaining the full resolution of CD (or even rather more). ]

Isaac,

You must go to the basics in order to full understand what is at stake here. Noise shaping is like the use of negative feedback in an amplifier except that it is not instantaneous, but encounters one-sample delay. With a constant input, the average quantizing error will be brought to zero over a number of samples. The more rapidly the input changes, the greater the effect of the delay and less effective the error feedback will be. There is nothing you can do about it, except bring down that sample-delay by rising the fs. If you want the same resolution as PCM you'll need a fs = 2.89GHz, period.

[In terms of technology, it would be entirely possible to make a DAC chip running at 2.89GHz. We can make a 60 million transistor computer processor run at 4GHz, so a simple (by comparison) DAC is easy. There is simply no need for it however.]

Well, in that case I should have said "no way you can have it with modern and COST EFFECTIVE technology".

[It's just the Opus does something - you'll have to listen to see if it's for you. Interestingly the two machines use very similar dac topologies, along with sperate psu's. They do however sound quite different to my ears.]

Merlin,

Even exactly the same topologie can sound quiet different when implemented by different persons, trust me.

[PMC 63K's and the 1702's to my mind coupled with the first generation 24 bit resolution enhancement chips, give that something I've yet to here in anything lately.]

Wm,

You surely have trusted ears.

 

And in which machines might we find these beasties?

reg


:Quad:

 

Copland's/Wadia's/Monarchy/Sonic Fronters/Primare/Assemblage/Cal/Bow, the Martanz cd7 I believe is also of this sounding Ilk too

 

The CD7 is twin Double-crown TDA1541s.

 

I know the sound is of the same era/type

 

[PMC 63K's and the 1702's to my mind coupled with the first generation 24 bit resolution enhancement chips, give that something I've yet to here in anything lately.]

[And in which machines might we find these beasties?]

[Copland's/Wadia's/Monarchy/Sonic Fronters/Primare/Assemblage/Cal/Bow...]

Wm,

You are not voluntarily missing the Naim CDS2, are you?

Reg,

ROTEL RCD-971 (PCM63) and ACCUPHASE DP65 (PCM1702) are also examples.

[As to the issue of delta/sigma bitstream etc, well I have heard CEC components several times and they've never failed to impress these ears and IMO, if the price is right and the sounds seduce, then the underlying technology pails into insignificance from my perspective.]

Lawrie,

The interesting thing about CEC is that they are using a so called hybrid DAC (NPC SM5865CM) that I'm not really familiarized with, and a proprietary filter, ringless they say. To quote their information:

"Bitstream (one bit) converters have an unbeatable low level performance, no glitch energy and a good low level linearity.
Multibit converters have a good dynamic performance and no need for higher order noise shaping.
The hybrid converters used in the CEC DAC have a bitstream converter for lower levels combined with a multibit converter for higher levels. The result is a DAC with very low glitch energy, only a first (or third?) order noise shaper for the bitstream unit and a very good dynamic response."

Now that sounds promising.

 

It does sound interesting. Don't Ayre do something similar with the CX-7?

reg

:Quad:

 

Yes indeed Reg. It seems to me that it is another marketing hype. Although I have no experience with the BB1738 DAC either.

But I really liked what I heard through the CEC TL 51Z, no lack in pace&rhythm with a nice boogie factor to boot.

As for the Ayre I've been told it sounds bland...

Due to financial reasons my final list is as follows:

a) CEC TLx51/dx71 combo;

b) Accuphase DP75 (used);

c) Accuphase DP65V (used).

I have no valuable experience with any of those machines. Except fot the CEC combo they all are multibit. Any further thoughts?

 

i've just realised i said i heard the cec with advantage gear when i actually heard it with ayre amps. sorry. i heard the ayre cd player at the same time as the cec in the same system - not impressed.
cheers


julian

 

Reg, they do, only the maths/theroy doesn't quite give the results in the real world, if I was left a choice better the Ayre and a Arcam cd23, I'd have the 23 anyday.
Bm, the cds2 doesn't rate as a cd player for me I'm afraid, its the anti-thesis of all the traits I value in music reproduction.
As you mentioned before same bits different implementation, only this time a back wards step.
The Accuphase can be made into a decent machine too, I'd forgotten that one.
Mind you changing the receiver chip from the obliqitory cs8412/14 can yeild interesting results that you maybe surprised over.
I have done a dx71?? dac (tasteful gold coloured too) in stock form very smooth, detailed and inoffensive, twin torriods, nice layout, good board work. disappointing result, took a bit a work to bring it up to speed, but twas cheap $1500 to the door.
Prehaps more time spent earwigging and less time spent festering with spec's may well speed up a purchase.
What about the new 'way out fave' 47 labs, prehaps this may well float your boat, the acoustic pepples certainly enhance the esoteric image.
Maybe you could educate Mr B in the trails and tribulations of a dac 64's sound projection technique? Wm

 

[Reg, they do, only the maths/theroy doesn't quite give the results in the real world, if I was left a choice better the Ayre and a Arcam cd23, I'd have the 23 anyday.]

Wm,

It's not theory, it is an hype. Either you have true multibit or you don't. Delta-sigma is no good, whether is partial or full implemented. It can be made acceptable but... not glorious.

[Prehaps more time spent earwigging and less time spent festering with spec's may well speed up a purchase.]

And I was thinking you were the one that said "changing the receiver chip from the obliqitory cs8412/14 can yeild interesting results that you maybe surprised over." Man, this really sound like spec's...

[What about the new 'way out fave' 47 labs, prehaps this may well float your boat, the acoustic pepples certainly enhance the esoteric image.]

No way I'll buy something like this:

http://www.hifi.nl/recensies.php?id=1966

Five star construction and carefully layout with costly chips...

 

There is a fair amount of discusion as to wether those pictures are the true 47labs items.

 

penance aren't they the new Shigaraki Series boxes, not nearly as uber cool looking as the flatfish and gaincard series.