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nightflier
11-02-2009, 03:24 PM
In my ongoing effort to downsize, I'm contemplating not getting a separate CD player, and instead using my Oppo as transport with a really good DAC. So would a $2K-ish DAC coupled with my universal player be as good as let's say a $2K-ish player, for 2 channel audio?

Or, put differently, does the transport impart anything audible on 2-channel sound?


FYI: PS Audio is reselling a slew of traded-in DACs at lower-blue-book value and I've been told that they have some very impressive ones to offer, so I thought I would see what they have. $2K ought to buy a very decent used DAC, and since they don't have too many moving parts, the risk should be minimal.

02audionoob
11-02-2009, 04:31 PM
I'd say PS Audio's own DAC is very decent. I like mine, at least. I just now compared my two sources on the DAC...a Music Hall CD-25 and an LG Blu-ray player. I can hear the difference.

blackraven
11-02-2009, 04:53 PM
Cheap transports may not have as good a laser and optical converter. I think that the Oppo would do just fine but you could easily test it in an audio store. Just bring your Oppo along.

Mr Peabody
11-02-2009, 05:12 PM
I have heard differences in transports. Mainly between cheap and better. For instance, I tried a TDK CD recorder and it made my CJ DAC sound not so good. Using my Krell CD player it still had an effect over the music in the DAC compared to an EAD transport which sounded much smoother in comparison. So I'm convinced there can be a difference. I personally would think the Oppo should make a decent transport.

Hermanv who uses a Levinson DAC which has a safisticated input buffer stage says he hasn't been able to tell the difference in transports. I know the buffer and reclocking has to make the difference. I don't know if PS Audio or anyone else does what the Levinson does but it sounds like a nice feature.

Ajani
11-02-2009, 07:25 PM
In my ongoing effort to downsize, I'm contemplating not getting a separate CD player, and instead using my Oppo as transport with a really good DAC. So would a $2K-ish DAC coupled with my universal player be as good as let's say a $2K-ish player, for 2 channel audio?

Or, put differently, does the transport impart anything audible on 2-channel sound?


FYI: PS Audio is reselling a slew of traded-in DACs at lower-blue-book value and I've been told that they have some very impressive ones to offer, so I thought I would see what they have. $2K ought to buy a very decent used DAC, and since they don't have too many moving parts, the risk should be minimal.

From my understanding (based on tests with my own DAC and reading testing of various transports in Stereophile) the main issue with a transport is jitter. Which is really a problem with older DACs, as many of the modern DACs such as the Benchmark DAC1 and Bel Canto DAC3 are virtually immune to jitter... so if you get a DAC with good jitter rejection, then a cheap transport shouldn't be an issue...

nightflier
11-03-2009, 10:53 AM
By the way, PS Audio isn't just reselling their own branded used DACSs, they are selling everything that has been traded in including everything from Full Nelson MSBs to Levinson and MLB processors. Last summer, on the launch of thier new $3K PWD DAC, they were offering trade-ins of any used DAC towards the purchase of a new PS Audio one, so they now have shelves of used DACs that they have tested, priced and that they are looking to resell. I still haven't decided on what I would like to get, but there's got to be something decent for my $2K budget for this.

blackraven
11-03-2009, 12:51 PM
NF, why don't you consider some of these new DAC's?

Benchmark ADC-1
Bryston BDA-1
Van Alstine Ultra Hybrid DAC

These all have a 30 day risk free in home trial.

or even this $4K used Krell SACDP from spearitsound selling for $1700 from www.spearitsound.com http://www.spearitsound.com/ebayimgs/sacd2a.jpg I'm considering this one!

nightflier
11-03-2009, 01:01 PM
Yes, the Bryston is on my list. Don't know enough about the VA, but Benchmark was also a possibility. Would like to consider others as well. A few of the criteria I'm looking for:

- A warmer, more organic sound than the Cambridge Audio DACmagic
- XLR outputs
- USB input
- 192KHz.
- Volume control (for going directly to the amp)
- Regular component size

I must confess that I'm a bit spoiled with my old stand-by: an Arcam Black Box, which is not exactly what I'm looking for sound-wise, but has just about every other feature except XLRs. It even has a remote!

blackraven
11-03-2009, 01:18 PM
I own the Van Alstine Tube-Hybrid DAC. It does not have xlr if thats what your looking for. It also does not have usb inputs. But what it does have is tremendous Air and Transparency. Its not exactly tubey in sound, its more neutral with a slight edge to warmth as all his gear is. It gives a very detailed sound with no digital edge at all. Resolution is excellent.

That Bryston would probably be #1 on my list. I love their equipment and wish I could afford an all Bryston system.

Feanor
11-04-2009, 06:59 AM
In my ongoing effort to downsize, I'm contemplating not getting a separate CD player, and instead using my Oppo as transport with a really good DAC. So would a $2K-ish DAC coupled with my universal player be as good as let's say a $2K-ish player, for 2 channel audio?

Or, put differently, does the transport impart anything audible on 2-channel sound?
...
The transport can matter. From all I've heard, the unwanted contribution from the transport is jitter, that persistant bugaboo. Also, most transports are connected to the DAC via a S/PDIF interface that carries sound bits and timing mixed together. To make matters worse, the S/PDIF cable, coax or optical, can make its own jitter contribution and that is why different cables can also make a difference to sound.

My understanding is a rather crude, but given S/PDIF, the DAC must separate sound bits from timing information; this is done by a "receiver" chip in the DAC. The separated signals are sent on directly to the actual DAC chip, or first to an upsampler chip and then the DAC itself. But note that this separation of sound and time by the receiver chip is not, as I understand, equivalent to full reclocking of the sound bits, and does not remove all jitter. Sadly, the receiver itself can contribute jitter.

Now, as I understand, an asynchronous upsampling process, (e.g. 44.1 to 192 kbps), effectively reclocks the sound bits -- one reason why upsampling might improve the sound. Note that this reclocking does not necessarily occur for synchronous oversampling, (e.g. 44.1 to 176.4 kbps). And the upsampler chip itself can contribute jitter (as you might have guessed. :o)

What is unfortunate is that there was always a better, inherently much lower jitter interface than S/PDIF; this is I2S interface (which is used internally in CD players). Unfortunately no standard connection method has evolved for this interface, so you tend to see it only between transport and DAC devices from the same manfacturer, PS Audio's PerfectWave transport & DAC.

I suspect that if the I2S interface was common between transport and DAC, that the DAC could effecively ignore the separate timing info the transport and reclock the sound bits internally. In this case the quality of the transport would be almost irrelevant.

nightflier
11-04-2009, 10:12 AM
Feanor, you're making me want to reconsider the PS Audio PWT/PWD combo, and I can't afford a $6K combo right now. Argh!

Mr Peabody
11-04-2009, 04:24 PM
You might check on some of the Levinson DAC's. Their buffer/reclocking input seems to do a great job of making the transport not significant.

pixelthis
11-05-2009, 12:13 PM
In my ongoing effort to downsize, I'm contemplating not getting a separate CD player, and instead using my Oppo as transport with a really good DAC. So would a $2K-ish DAC coupled with my universal player be as good as let's say a $2K-ish player, for 2 channel audio?

Or, put differently, does the transport impart anything audible on 2-channel sound?


FYI: PS Audio is reselling a slew of traded-in DACs at lower-blue-book value and I've been told that they have some very impressive ones to offer, so I thought I would see what they have. $2K ought to buy a very decent used DAC, and since they don't have too many moving parts, the risk should be minimal.

Absolute Sound has the 169 oppo listed as a great beginner CD player in their latest buyers guide, but suggest an upgrade to the 499 blu if you have the scratch.
If those snobs like it....
Really tho, expensive players use transports made by the likes of Sony, etc.
Long as it turns the little silver disc round and round.
Main thing for any digital music is the DAC.:1:

RGA
11-06-2009, 10:37 AM
Yes they matter - just don't expect transports in sub $2,000 players to be any different or better than transports in the sub $500 range. None of the "name" CD player makers make their own transports in the budget model realm. They are all purchased from other companies and as a result the same exact transport could be used in dozens of models. Transports matter at higher price points.