Rega's ISIS CD player is here

I know what it is - but when I looked it up I found this great explanation; in the Isis case it would be used as a hi-rez in/out for the DAC:

SPDIF is used for transporting stereo digital audio signals on PC audio cards, CD players, DVD players, car audio systems, and other systems which transmit or receive stereo digital audio.

For S/PDIF, two 192 bit blocks (left and right channel data) is divided into 12 words of 16 bits each. The first 6 bits of the first word are a control code.

The SPDIF protocol does not specify a given data rate or resolution. The actual equipment containing the SPDIF connectors must determine the data rate "hand shake" from the mutual SPDIF signal accepted by both pieces of audio hardware.

For greatest flexibility, the SPDIF protocol utilizes the Bi-phase mark code (which has either 1 or 2 transitions for each bit). This allows the initial word clock to be directly extracted from the base signal, itself.

The most common SPDIF data rates are 44.1khz (stereo CD audio) data rate and 48khz (DAT- Digital Audio Tape) data rate.

While typical SPDIF transmissions are limited to 16-bit audio (due to audio CD limitations), the SPDIF protocol actually supports 20-bit audio.
Furthermore, the SPDIF protocol can be after-market adapted to support 24 bit audio (with an extra 4 bits). However, 24 bit audio is not directly supported by the SPDIF protocol.
In order to transmit S/PDIF signals having less than 20 bits of bit rate sample accuracy, the unnecessary bits will automatically be "shaved" to zero (off).


Another silly Sony/Phillips proprietary invention? I'd think something more universal like 10/100 could/would work in an audio setting?

 

most DAC's have an RCA/SPDIF digital input...

It's just another way to get a music server connected. I'm sure USB is definitely the wave of the future.

 

The problem with USB is that it was not designed as an audio/video data transfer standard in the way Firewire was. It does not have dedicated, standalone hardware-based control of data I/O the way Firewire does. USB requires too much overhead and as such, has to steal CPU processing power to manage data transfer. It also doesn't have the bandwidth that Firewire does. You need a computer to run USB, but you don't need one to run Firewire. My understanding is that USB is limited to 96kHZ/24 bit, but you can run 176 and 192 KHz/24 bit over Firewire. This is why forward-thinking companies like Weiss and Metric Halo have implemented Firewire support for their DACs.

 

Being pro audio companies, I think that makes good sense. But considering there is almost nothing to listen to in 24/192, I don't see it as a deal breaker.

As with any product at this price point, one will have to weigh the pros and cons.

 

There isn't yet...but there may well be in the relatively near future.

 

24bit/96khz is the limitation of USB 1.0, no one has implemented usb 2.0 in any dac

 

That part is true.

There's plenty of CPU to go around.

As I said above, since there is no implementation of asynchronous Firewire because no operating system supports it, I'd go with async USB.

 

So Jeff, how is it comparing to your Naim CD 555?

 

At this point it's really damn close....

I talked to my pal James at TomTom audio over in the UK who sells both and he has also said the same thing.

But, on deadline right now for issue 24, so once that's done I can spend a couple of days really comparing a lot of material.

Either way, I still love my 555, but the ISIS is fantastic. Another thing worth mentioning about the ISIS, is the packaging and presentation is fantastic, and keeping with a player at this level. In addition to a gorgeous billet remote, it comes in a foam lined crate with a very nice set of interconnects included (probably worth about $4-600 if you purchased elsewhere) and a good power cord that would probably be worth the same.

The other player that I'm anxious to get my hands on is the new one from Sim/Moon that has the world's first 32-bit asynch. DAC. (and a future upgrade for an external power supply...)

It's pretty exciting to see this much going on with CD at the end of it's life. Much like LP!

I think if you are looking for a final destination CD player and also are thinking about using it for a USB DAC, the ISIS is well worth a trip to your dealer to audition!

The review will be out shortly....

 

Thanks Jeff for the feedback. Yes the 555 is an easy thing to love. I did hear the ISIS briefly in James room at the UK hi-fi show. Look forward to reading your review in the near future.

Cheers

 

The 555 costs more than 20 grand afaik ?
Besides the before mentioned Einstein THE SOURCE it is especially the new
Audio Research CD-8 for 10.500 Euro , that might be interesting to compare to the world's best sounding Cd players.....

 

Seems silly to spend this much on a player that can not play SACD...and I am a total Rega junkie... But for this money, I would want something that can play higher resolutuon than redbook... Just my 2 cents...

 

'World's Best CD-Player' (!) ???

 

Not a chance. ARC has never made a transparent sounding cd player!!!

 

The build quality sure is impressive.

 

I have mixed feelings. At a given price point, there is something to be said for optimizing CD playback since it remains the leading digital disc-based music format. Either Rega did not want to pay the licensing fee for SACD or they felt that CD playback in the ISIS would suffer if SACD were included.

On a related note, I think high-end audio manufacturers at times test the limits of their capabilities in their designs without necessarily considering what the consumer wants. I can appreciate the challenge of making the best CD player possible at a given price point, and making a statement in the process, but you have to be able to sell it at the end of the day. For me, SACD would make the ISIS more appealing and a more competitive offering. Of course, they are not alone in offering CD-only players in the high-end realm.

 

That about sums it up for me too.

Call me a dinosaur but I don't care about USB this or SPDIF that.

I want to play my discs on it...that's it.

At that price it needs to play SACD for me to bite.

 

If Oppo could support SACD in a $169 player, Rega should be able to do so for $9000

 

Yeah, that's kinda what I was getting at...I'd prefer a player to be inclusive, not exclusive at the extreme high end of the price scale...but that's my personal preference as a seller, and as Jeff said 99.99% of CD collections are redbook CDs + use as a DAC does allow for HiRez capability.

 

Yeah, but it wouldn't sound like a $9000 player. The Oppo plays everything but it doesn't sound like much. I'd much rather have 16/44 done right than cheapo high res. Sorry.

Supporting a format is one thing, making it sound outstanding is another...

 

From my pov SACD is dead and gone long before it was even born. I have more than 1000 CD's and not a single of them is a SACD. There is even a stronger demand for classical audio in DVD-suround sound, which to me sounds like much more interesting path to follow than this Stereo SACD thing. ( More than 1000 DVD-Audios in SA-Surround available atm. and getting more every day...)

The major problem is that SACD-drives usually make the reading process a boring long one, even with red book CD's and you don't find as many good drives supporting Super Audio and it is more difficult to finetune a CD-drive with SACD function.
I see this SA thing more as a gadget for entry level audiophile players, like a Marantz PM 8003 or a Pioneer A9 as a cheap way to boost the performance level . Wouldn't you prefer your redbooks sounding better via the ISIS than SACD's on your 2 K player ?
The difference between redbook and SACD perfomance on audio magazine reference player Accuphase DP-800 / DP 8001 dp is just a meagre 5 points (the smallest difference) from 135 points via redbook to 140 with SACD.
The new audio research CD 8 doesn't offer SA as well and reaches the same 135 points with redbooks. The only other player that reaches 135 with SACD is the new MacIntosh (125 with redbooks). You see the difference in the medium is not that large once you optimize the true possibilities of the old CD format.

 

You nailed it. Exactly what I was trying to commumicate with more words...