Dac Questions from an Analogue guy :


As you can see from my Forum name I am a vinyl enthusiast at heart but do from time to time have digital needs so to speak. Upon learning that my DAC on my old CAL LABS ICON MKII Cd player seems to be dead as there is no audio out of the RCA's I figured I would use the digital coax O/P utilizing a friends PS audio NUWAVE DAC since I have never used the digital coax out before. I figured the player was not totally dead because of the fact that when a CD was inserted into the transport all the of the CD info appeared on the player. So I gave it a shot and voila it worked with very nice results. Simple, done. My curiosity furthered me into the other connections on the unit being the USB and the optical. I gather the Optical acts as a link such as the digital coax from my CD player but the USB connection puzzled me a bit. Having looking at the specs of the DAC, it of course is capable of 16/44 audio but can also do 24/96 and 24/192. Of the 2 latter formats, how are these utilized? Through the USB say using a computer or note pad device? I did not do any research as you can see, so these questions I know are rather rudimentary. Do correct me if I am wrong, is the 24/96, DVD audio? ANyways, my whole curiosity of this is how one utilizes the USB connections and all the higher resolution audio features of this DAC. How is the overall Audio quality of these formats? What are my options if I want to delve further into this? yeah I looked on the Net and saw a huge plethera of products which confused me even more so you can say I am a bit brain lazy when it comes to this whole digital format.
I do have an Ipod with MP3's mostly for my car but I can't see that being the end to be all to be utilized with the Dac since I personally find that this overlly compressed format to be inferior. Anyways, any answers starting from 0 would be greatly appreciated.
vinylmad814
DVD Audio is a different format, similar to SACD I think. 24/96 and 24/192 are high resolution methods of recording music. You must use a laptop or computer to pipe 24/96 or 24/192 music tracks into your DAC, but to play DVD-A or SACD discs, and these formats only comes on discs as far as I know, you need a compatible CD player. DVD-A has pretty much gone the way of the dinosaur, SACD won that battle. Check out SA-CD.net for current titles. I don't think the SACD signal can be sent into the DAC you have, you'd need a new player.
If you own CDs currently, you can rip them to a lossless format like .aif or .wav and they might sound better on your iPod, but this depends heavily on how you get the signal from the iPod to your vehicle's stereo, typical methods for this harm the sound quality and won't beat the SQ of an in-dash CD player.
You can rip your vinyl to digital files, using a number of different software packages, and play them through your DAC using iTunes, JRiver or FooBar from a computer or laptop. You can do the same with your CD collection, just use lossless formats, not .mp3...
I don't think your ICON player can output anything more than a 16/44 signal, so a lot of your questions might not be applicable just using that transport. Some DACS can "upsample" that signal to higher levels; I have ultimately found that to be a mixed bag, as it adds a bit of noise to the playback. I can tell you that, in my view, the higher-resolution sources, be they 24/96 or 192 via a download or SACD, do sound better than a standard 16/44 CD, closer to (but certainly not the same as) your analog setup. The differences are more subtle, IMO, in that they just make the music sound more like a real event than a reproduction--I'm sure you probably have that feeling listening to vinyl vs. CD. You won't be able to get SACD playback from your current setup; you'd need a transport that can read an SACD and a DAC that will accept and convert the DSD signal; the standard CD signal is PCM encoded, a different system.

For computer audio questions, which may ultimately be the best way to go, you'll need to look elsewhere than me for any specific advice. I can tell you that my Memory Player (which essentially is a computer) does sound significantly better playing a CD from its memory than the same CD played on a very high quality transport (using the same DAC), and I'm sure from having heard good computer setups out there that they can make the same claim. It also is quite convenient, you'll see if a friend of yours has a good computer setup just how easy it is to store, organize and play back music files. You won't have that tactile feeling of putting a record on the turntable/CD in the drawer, but I'm very impressed with what a lot of these computer-based systems bring to the table.
Are these high resolution 24/96 -/192 files, flac files. The reason I ask is that I have lent over 300 discs mostly classical and jazz titles to my friend who is going to convert these files to his computer. I believe he said something about Flac files. You know I think he has some kind of interface on his Ipad to run these files. I suppose I should ask him lol. ANyways, would the files he is converting from my Cd's to his hard drives be these 2 higher resolution formats or are they just the 16/44 format?
The main reason I am even considering this is mostly to at least put part of my music collection on a digital format to make room for more vinyl. Since i do not intend on purchasing all these classical titles in vinyl, I figured this digital option would be a great alternative.
If you lent CDs to your friend, I don't think he can turn them into any hi-resolution files, he only has 16 bits and 44khz to start with. As I said he may do some upsampling, but that won't make them into what I'd consider to be a hi-rez file.

For your basic question, you'll need more help from people who know about downloading and computer audio, I'm not good at that.
Vinylmad814, I have a computer based front end, and have done extensive research in the areas of redbook CD playback and upsampling. The CDs you gave your friend can all be ripped to FLAC, or WAV, or AIF, all of these are lossless formats. WAV and AIF can be played by pretty much any software player out there, FLAC cannot be played back on iTunes to my knowledge. High-res files, i.e. 24/96 or 24/192 files you buy on HDtracks.com, can also be formatted into these same file types. What you will get from your friend ripping your CDs will be 16/44, which is the standard for CDs. 16/44 can still sound very, very good; like everything else, it is all about the quality of the recording.
Upsampling is not the same as playing a high res track. Your DAC upsamples the signal to 24/96 or 24/192, but the music signal you are sending the DAC is 16/44, if you are using the CD rips your friend is providing. Upsampling is pretty much what all modern DACs do, it re-samples the 16/44 track at a much higher rate, and it is supposed to push noise artifacts beyond the range of human hearing. Highs are supposed to "smooth out." I cannot really test the difference between a 16/44 track played at 16/44, and that same track upsampled to 24/192, because my current DAC upsamples only, I don't have the choice of non-oversampled playback. So I cannot say that upsampling sounds good or bad, I got into this computer-based-audio thing kind of late. I can say that my PC-rig mops the floor with my Denon changer in sound quality, but the cost differential makes that comparison unfair.
If you purchase iTunes music in 256K mp3 format, those are *not* high res files. the MPEG3 codec cannot push high-res data at that low of a rate (256K).
Thanks for the info folks. I just had a chance to go and see a high end audio provider who's main focus is analogue but has been impressed with some of newer digital advances in the past couple years. He is now a dealer for Weiss, a manufacturere of high end Dacs. Like 6 or 7 K!!! Anyways, I just learned of how these high res masters come. With the Weiss Dac a DVD disc with 24/176 files. No player can play these files, so they have to be downloaded to a computer and played through some type of media player of some sort to utilize these files. I must say they sound absolutley fantastic. The best digital sound i have ever heard, hands down. Mind you this is played on a $7,000 dollar Dac with files that have been mastered utilizing this high bit/res rate. From what he understands alot of the material available is not originally mastered at this high level which in turn goes through an upsampling process. Apparently some of these files do not sound all that good and are not worth the cost over its 16/44 counterparts. So buyer beware. Well i am going to have to press on further and actually to a sound test. I can't believe the digital realm has me mildy stoked. lol
I go to RMAF every year, and have heard some truly incredible digital-based systems there. A $7000 DAC is not a price range that I will ever be in, but happy listening to those that are!
Some imortant things to understand about USB and computer audio:

1) Just like jitter from a CD transport, jitter from a USB interface is the most important sound quality issue - each USB interface has different jitter levels and therefore different sound quality. Think of it like a phono cartridge. The better the cartridge and technology, the better the sound.

2) You do not need any special server. A Mac Mini works great playing iTunes, however SQ can be improved by loading better playback software such as Amarra, Pure Music or Audirvana. You actually have a better chance of great SQ by using your own computer because you have control over the ripper, music formats and plaher software etc.. This does require some work on your part though.

3) Another option which can also deliver world class SQ is using a networked device such as Sonos, Squeezebox or Apple TV. A reclocker such as the Synchro-Mesh can lower the jitter of these and then feed a good DAC. Like a Transport, these usually only support lower sample-rates such as 44.1kHz.

here are some more tips:
http://www.empiricalaudio.com/computer-audio/

Steve N.
Empirical Audio
Been on a rather lengthy hiatus from the digital world. It seems Apple works very well as a USB driven system such as a Imac mini integrated with an IPAD or IPOD touch if you want remotely access your files. If you try to use an external hard drive for extra storage to access whether you are using a MAc mini or PC laptop, does this add an unwanted signal path that can affect overall clock speed timing or any other audio performance issues?
The external hard drive is usually not a problem providing that you interface it with external SATA or Firewire and not USB. If you are doing USB streaming audio then this should be the only USB device.

Steve N.
So I gather that if you do use a Mac Mini, you would need an external drive device given that you will want more 2 TB of storage. I did not realize these drives had a firewire or SATA connections. Also I was wondering if USB 3 connections make a difference for overall performance(ie SQ, Jitter correction etc etc). I know some of external drives have USB3 out but do DACS have USB 3 compatability? Does it matter?
The best configuration is a Oct 2009 Mac Mini with a firewire external drive for the library. Only use one USB port, the one next to the one in the middle of the chassis. Ports matter. Best to replace the HDD with a SSD from otherworldcomputing.com. More details:

http://www.empiricalaudio.com/computer-audio/recommended-systems

USB 3 will not make any difference. The thing that makes the difference is the USB DAC or USB converter that you choose. You get what you pay for. The performance of these runs the gamut.

Steve N.
Empirical Audio

Vinylmad, in regard to 24/96 and 16/94, there is a big difference, but only in regard to HD downloads. 44.1 KHZ is the standard sampling rate for CD's, 96 KHZ is what you want from a HD download. That would read 24/96 for a high resolution down load, and it's better than a regular CD; as a matter of fact, it's better than "my" analog rig, although it may not be better than yours. You will have to try down loading and then play it back through your DAC to find out when you compare it to analog.

Enjoy the music.
Steve, I have an October 2009 Mini. I'm currently leaving the Mini via USB. Which of the five outputs do you recommend?
If the USB port next to the edge of the machine is #1, then you should be using #4.

BTW, I have a Hynes supply that I'm using for my 2009 Mini. Huge improvement. Its a big one, about $850-900, but the dynamics are killer good. I'll be importing them soon.

Steve N.
Empirical Audio
hello again,

So I am looking at buying a very entry level DAC no more than $500 tops. Like I said, I prefer listening to my Lp's and have invested quite a bit of money on my TT rig and Line stage but I do want to play some Cd's since I do have an older Cal Labs Cd player with a working Digital Coax. I also would like to try out some of the 24/192 music that is out there. Oh yeah and another thing,the CALABS inboard DAC has packed it in.I have seen a couple of units on EBAY that have caught my attention. One for around $400.00, the TEAC UD-H01 and a VALAB Dual WM8471 24/192 for around $340.00. Yeah I know, cheap ass units but that is what I want to spend, period. Brand wise TEAC is probably the unit that will most likely stand out the most of the 2. The Valab being an Asian offshore product will most likely raise a few red flags for most. Mind you the specs that were listed and from what I have seen by viewing the photos of the unit on EBAY, the configuration of the circuitry and the general esthetics of the Valab, makes it look quite attractive. Both units have balanced outputs which is what I need since my Preamp is a BAT tube unit. ANy thoughts on these 2 units?