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I have a five-year old Harmon/Kardon cd player and am interested in going with an offboard dac. There seems to be a growing number of 24/96 dacs in the market now, most notably the MSB and PS-3 units. What I don't understand is how many cd players with 16 or 18 bit on-board dacs can really fully take advantage of a 24/96 off-board dac ? Don't these older players only output a 16 or 18 bit signal ? If so, then why are companies marketing their products as if you will be getting 24/96 resolution simply by popping in the right disc and using their dac ? Any answers out there ?
Don't be misled by the 24/96 etc. claims of various DACs.
A CD and thus the digital output of ANY CD player or transport is no more than 16 bits 44.1kS/s or kHz .... Period. Whether a DAC or other device "changes" this data to a different format has nothing to do with the digital source, namely the CD.
A CD player as a transport has nothing to do with the external "manipulation" of the data from the CD.
When you use an outboard dac with a cd player you are not using the cd player's dac at all.
The cd player's dac is not related to what an outboard dac is capable of processing.
Standard cd data is encoded at 16/44 (meaning 16 bit samples at 44k sampling rate). This is the information that is sent to the digital output of the cd player and hence the input of the outboard dac.
If a dac performs any kind of updampling it still uses the 16/44 data because that is all that exists on a standard cd. There is a whole debate about the results of mashing 16/44 data to synthetically produce higher resolutions - you can decide for yourself where you stand.
A standard cd player is not capable of playing true 24/96 media. If you want to get at this higher resolution source material you need to buy a player capable of reading it.
Ah, therein lies the question. What is the difference between reading the data and what the dac does ? What, in a standard player limits it to lower resolutions while other newer players can "read" higher resolutions ? These questions, because all I'm hearing is that it's only the disc and the dac which determine resolution and sampling rate. There must be another element here in the transport/reading mechanism or circuitry that enable it to read 24/96 or whatever. If I put a 24/96 disk into my 18 bit player and send the data to a 24/96 capable off-board dac, why the hell am I not getting the resolution that is on the disk ? And why do modern dvd player with 24/96 dacs downsample to 48kHz to the digital output ? Apparently, there are only a couple of players that send a true 24/96 datastream to the digital output ? Why, why, why ?
Just want to understand this whole mess.
If I put a 24/96 disk into my 18 bit player and send the data to a 24/96 capable off-board dac, why the hell am I not getting the resolution that is on the disk ?
I say agin, your standard cd player can NOT physically read a 24/96 disk. Therefore you CAN'T send 24/96 output from your cd player to an external dac.
Great, now I know that it can't read the disk. But my question is why not ? It was stated earlier that only the disk determines the outputted data, but this can't be correct. What enables one player/transport to read higher bit/kHz discs ?
I have stated the facts plainly, twice, and frankly can't understand where you are coming from. Hopefully someone else will be able to help you.
I hope they can too, Nick, because, although you have provided some intersting and relative information, you have not answered the core question, namely, why can't the transport mechanism read data other than 16/44.1 ? I have asked this question more than once and it hasn't been answered.
Please try to understand the following:
A CD disc is formated as 16 bit and 44.1kHz and a CD player/transport can only read this type of disc. A DVD (24/96 or 24/192) for instance is a totally different format and requires a different laser to read them. SO ... a CD player CANNOT read ANYTHING other than a normal 16/44.1 CD. Period ... end ... out!!!
And, don't be fooled into to thinking a Cd lables "24/96" is a different format. It is still just 16/44.1 but the "MASTER" was made at a data rate of 24/96 and "downsampled" to 16/44.1, the CD standard.
GOT IT NOW?
a CD player can't read the pits/lands in the trough on a DVD Video Disc, or why a CD player can't read SACD/DVD~A discs either. It has to do, in some cases, with the laser's wavelength. The bits on a SACD disc are more closely spaced/deeper vs. CD and this is more or less the same for DVD~V. That's why every DVD~Vp has either two lasers, or two lenses to focus the single beam differently. They may look the same on the surface, but they ain't!
This can also be a software issue in the transport. The Sony 7000 DVDp could not PASS a DTS bitstream, let alone decode one. It didn't have the algorithm to make heads or tails of what it was looking at.
The Discs all use different formats, they are NOT the same internally and once you get over this hump, you'll have the answer to your question. There are no 24/96 CDs. Period. Your CDP can't read them, because none EXIST. Your CDP can't can't read DVD~V, DVD~A, or SACD discs (and in many cases CD-R & CD-RW) because they ARE NOT CDS.
For most practical purposes, 24/96 DACs are overkill, especially if one only does CDs and no upsampling. I'm sure the digital gurus will tell us that they can help, but I'm not smart enough to tell you why. They are being made/marketed more frequently than the 14, 16, 18, or 20 bit dacs and are easier to buy in bulk and install these days. DVD~V music discs, in the right situation, can give one the higer resolution that the 24/96 DACs are meant to produce, but your player has to pass the 24/96 signal w/o downconverting, either at the analogue OUTs or at the Digital OUT (usually done).
To give you an idea, my Toshiba 2200 w/24~96 DACs will only pass a 20/96 signal from the 6 '5.1' analogue jacks on the rear and it will only pass a 24/96 signal through its two channel analogue jacks, when playing a DVD~V music disc. I will only have the higher resolution in STEREO, not surround. The COAX/Digital OUT will only do 16/48 due to copyright/piracy issues. So, just because I'm playing a 24/96 DVD~V disc through my Denon 3300 with 5 kick-ass 24/96 DACs, doesn't mean that's what I'm hearing. It's very complicated and one best read the manual first, before buying.
I must have read this post three times before submitting. Oh well, that's why an editor proofs the writer. A different set of eyes.
Chris, thanks for that explanation. Superb !
All that said, doesn't it seem a bit dishonest the way 24/96 is being thrown around these days ? I mean, I read a lot and I am just now understanding how all of this stacks up. Sounds like a lot of marketing hype to me.
Up until DVD-A and SACD how many levels of encoding resolution were there ? And now that I have a used Link DAC II on the way, what is it that is creating the sonic benefits reviewed ad infinitum ? Lower jitter or what ?
Again, thanks for the help.
Well the Redbook standard is 16 bits sampled at 44.1 kHz. DVD~A can do 24 bits at 192 kHz, but I guess, only with dual AES/EBU runs. I'm foggy on this concept. DVD~V does 24/96. Sony is supposedly using a 1 bit 2.5 (?) mHz sampling rate, but really an 8 bit converter. At the recording console/master tape, people can do a combination thereof, and Chesky does some 24/96 discs and JVC XRCDs are 20 bit/K2 processes, but I'm going to put my foot into my mouth, so I'll stop here.
I guess, the benefits of an outboard DAC might be in better parts used. Rodney Gold is pretty smart in the digital arena, as well as Steve, Peter, Garth, and RBP, so you might do a SEARCH on their names and read up on their thoughts. I'm a stupid layman susceptible to marketing mumbo jumbo.
You wanna here something really neat? I'm about to hook my Hi Fi S~VHS player up to my Sony SCD-1/preamp and do a recording of an SACD for Bill Roberts (engineer.) He thinks that he'll have a better idea of the format's sound and that this analogue tape will be pretty close to what's on the disc. Neat, huh?
according to Garth, who posts here and seems to know a bit, the SP/DIF interface (either RCA or BNC digital out on 98% of digital gear) only supports up to 24/96 anyway, so for all practical purposes, there exists a bottleneck, similar to a bus speed on a motherboard in a computer.
Yes, it is marketing. What most people don't understand is the limitation of each disc in question. Many love upsampling (where through math, things can be stretched) others don't. Peter Qvortrup and Audio Note don't even use Digital Filters, others do. I wouldn't get hung up on any of it. 24/96 DACs do work in the context of DVD~V, if everything else is in line. However, it's just easier to throw the higher rez. part in and tell everyone, you've got a better DAC.
Heck, most systems probably can't resolve the differences anyhow! My ears are clay, but I think my system is capable. Remember, people think that just because they can HEAR, that this fact makes them a GOOD listener. One needs a trained ear and I don't think I'm entirely there yet, myself.
Anyway, it's best to try and listen to as much gear in your own system as possible. If you can hear a beneficial difference, then consider that piece.
Glad I`m not the only one with ears of clay! Reminds me of the time I went to a demonstration of Kimber Cables and various tweaks by Russ Andrews (Kimber distributer and `Guru` over here). First he replaced IC`s, then speaker cables, then mains cables, then oak cones under equipment - and if the rest of the group were to be believed I was the only one who didn`t hear the improvements after each stage - although I wasn`t convinced. However, I then asked Russ to change back to the original set up all in one go, and the difference was incredible (I now use Kimber). Personally, I find it very difficult detecting changes in A/B comparisons, but if I have time to adapt to a certain sound, it`s easier then to detect a deterioration. As far as the 24/96 DACs, the first rule of marketing comes to mind - applies to all aspects of Audio - `If you can`t do it better, do it different`
The dacs resolution and wordlength are source dependent. The 24/96 Dacs can play normal cds, but you will NEVER get performance like that of a 24/96 source (such as DVD-A or high bitrate sound from DVD-V). Some offer upsampling as an option, but it is not nearly as good as true 24/96. Upsampling tries to use higher resolution than is possible from standard 16/44.1 , and many feel it is a better way to process the signal, but it will never ever ever be 24/96, just an approximation thereof. Hope this helps.
Digital output from a transport or player is only what is on the CD -- 16 bit 44.1kHz. (Some DVD players can output 24 bit 96kHz, but only from the relatively few audio DVDs recorded using the DVD Video standard.) Starting with 16/44, however, there are devices to upsample to 96kHz (several DACs include such upsampling), and there are a few devices which also interpolate 24 bit words. Those processed digital signals can then be converted in a 24/96 DAC.
Without such upsampling or interpolation, however, you are correct in assuming that a 24/96 DAC does not necessarily bring anything to the party.
but the short version, depending on who you speak to, is that they upsample.
O.K., but my intended question hasn't been asked completely. Is the resolution in the method of recording the disk, or how that data is read by the transport and sent out the digital out ? There are lots of DVD players out there with on-board 24/96 dacs which don't even output the same but rather downsample or convert to 48kHz. Maybe we are talking about two different things; 24 being word length ? and kHz being sampling rate. So am I correct in assuming that the DVD players, while not sending a 96kHz signal to the digital out are sending 24 bits ? If two players, for example, my Harmon/Kardon 7325 with 18bit dac and a player with 24/96 dac, read the same 20bit or 24/96 disk and send the signal, via coax, to an MSB Link DAC, what difference will there be in the MSB's output to the amps ?
I think you're making this harder than it needs to be.
First, no disc can be read at a higher resolution than it was recorded with. For the typical CD, this means 16/44. You can place this CD into a transport built by God and it still won't pull off more than 16/44. Period. That stream can then be sent to a DAC that will _upsample_ it to 24/96 (I leave it to others as to whether this improves the sound), in which case you need a 24/96 DAC to play it.
As for "true" 24/96 discs, any transport that can play them will pull off the 24/96 stream. It doesn't matter if this stream is sent to a DAC that then _downsamples_ it to 24/48 or something else, the fact is the stream was read at 24/96. Most of the 24/48 downsampling in these DACs is done for purposes of copyright protection, not because the DAC couldn't handle it.
Of course, if you put the 24/96 disc in a regular CD player it can't be read (well, assuming it doesn't also have a 16/44 stream). Why? It's a different format. Just because a DVD disc and a CD look the same, it doesn't mean they are.
As for why so many CDPs have 24-bit DACs, that's marketing and economics. This isn't new, 20-bit DACs were all the rage the last couple of years.
Finally, to answer your last question, your HK is going to read a 16/44 stream and send same. Your alleged player with 24/96 would read a 24/96 stream when playing a disc recorded as such (there is no such thing as a 20-bit disc). Would that alleged player _output_ the 24/96 stream? Maybe not, it may downsample it to 24/48 before output. For example, my Pioneer DV-626D has the option to output at 96KHz. But even if I use that option the manual says that for discs with copy protection the signal will still be digitally output at 48 (the analog output will be 96, however).
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