Jump to content

Opinion Requested re: DAC


Recommended Posts

I know, strictly speaking, this is a speaker site but there are a lot of reasonable enthusiasts here who may be able to help me with a question I have regarding outboard DACs.

First a little background. A couple of years ago my CD player broke and instead of replacing it I decided to employ a computer full time as a music source using multiple Apple Airport Express units as wireless digital interfaces for the various receivers and integrated amps around the house. All speakers are pre-1980 3 or 4 way ARs with 10" or 12" bass drivers.

One of the receivers has an onboard DAC connected via Toslink so the Airport DAC is bypassed. All of the others are connected through RCA plugs and use the Airport DAC to convert digital to analog. To my ears there is no qualitative difference in sound aside from the obvious difference in speakers and rooms.

Before my fairly cheap CD player broke I would occasionally compare the two sources and considered them to be substantially the same in sound quality.

The music sources of concern are classical music CDs and Lossless files. I am out of the vinyl business.

My ears are old and can hear to maybe 13khz. I listen to music for the emotional experience and don't care if the system will resolve the difference between a Yamaha and a Steinway or a Stradivarius and a Carruthers but I do expect to hear the difference between a viola and violin or french horn and trombone. To sum up I am moderately discriminating with my equipment snob years well behind me.

Now I am thinking about purchasing an outboard DAC for one of the systems to place downstream from the Airport, which will remain as a wireless receiver, and also provide a USB connection for notebook PC.

My question is: Do any of you have direct experience with built in DACs of the type described and, if so, to what degree will an outboard DAC of say $400 or less improve the sound if at all?

I know all ears are different so I am really just asking for opinions from those of you who have DAC experiences and who wish to contribute your 2 cents.

Thanks

Adams

Link to comment
Share on other sites

If you are happy with the airport Express DAC, and onboard DAC in your receiver, which are serving others sets of speakers, then $400 seems like a lot to pay for a standalone DAC. Now at that price maybe you should ask to try before you buy, and judge for yourself if there is a difference worth paying for. I do not know the answer to that but I can say that I am perfectly happy using a cheap DAC, and am too content with the sound quality from my computer set-up into AR-16 speakers to bother with higher price DAC units.

Link to comment
Share on other sites

Thanks Jeff. I have been thinking about a try and buy but thought I would see if I could find a shortcut by asking other users. This DAC business reminds me of cartridges. With MM cartridges, as I moved up the Shure and Stanton lines incrementally, I liked to think I could hear a difference until I got a V15 Type 5 at which point I really could hear a difference. I never tried MC units which seemed esoteric if not exotic and finicky and certainly more costly.

My early CD players with their first gen DACs did not sound as good as the V15 but eventually the CD sound caught up to my vinyl system and I made the switch. To my ears and memory I am at a V15 level which is pretty good. I have just been reading about all of these "great" outboard DACs and been wondering if there really is anything to it.

Like you I am pretty satisfied with where I am now.

Adams

Link to comment
Share on other sites

  • 2 months later...

Hi Adams

I do not know what you decided to do about a better quality DAC but I recently came across this interesting article about DACs. The link takes you to the conclusions page but you can jump to any of the other 19 pages of the article comparing four DACs from $2 to $2000. The results are rather surprising.

http://www.tomshardware.com/reviews/high-end-pc-audio,3733-19.html

Link to comment
Share on other sites

I am a bit surprised they did not discuss headphone amplification in that article. My ASUS sound card I added to my PC has headphone amplification which I think many good phones need or benefit from. That seems like it would be a big negative with the realtek choice.

My ASUS card also has optical out so I connect to a Yamaha receiver and it's built in DAC, but I also have the Emotiva DAC I could easily connect it to as well and get the benefits that the article spells out about the $2,000 version.

I think the article sort of misses one of the big points of using an outboard DAC and that is the ability to plug in numerous sources beyond just the computer to one controlling device.

Link to comment
Share on other sites

David, before you added the Asus soundcard, I would bet that the PC had a headphone jack, most do, if so that is your headphone amplification. The PC I bought in 2008 (on which I am typing this message) has headphone out, line out, S/PDIF optical out, all provided by the onboard Realtek ALC888S codec. It also has onboard HDMI out provided by NVidia.

I believe each DAC used in the test provided its own headphone amplification. The whole point of the article was to test how the onboard Realtek ALC889 fared against the other more expensive DACs. The test concluded that the Realtek codec (headphone out) is on a par with the other DACs for sound quality, but acknowledged that it lacked the features of the more expensive DACs, as you have noted in your final sentence.

Link to comment
Share on other sites

Jeff

Thanks for the link. It was just today that I saw activity in this thread. I read the article and correct or not, it reinforces my suspicions that there just isn't much difference in sound quality from one DAC to another. There might well be an outlier on the market that is truly better sounding but it has yet to make itself known to me in an easily verifiable way.

As an update, a large part of the funds that would have gone to a new laptop and dac went instead to a MAC 4100. How I was diverted is another story but I was not sufficiently sold on the need for a new DAC without having the new computer.

I am however sold on digital over vinyl,especially using lossless files, with classical musical or any type of music that benefits from the much lower noise floor compared to vinyl, a difference I believe which translates to a wider dynamic range and truly does make silence part of the musical experience at home.

Adams

Link to comment
Share on other sites

There are a bunch of great discussions about DACS on other web sites that are more dedicated to the digital domain and it is interesting to see what folks think. There is a fair amount of concern about all the noise that the computer adds to any signal being produced from it and many outboard DACS are favored simply because they clean all that up. Now, can we really here all that, not sure. Maybe at times and depending on what equipment the signal is going to and being used to listen to it.

Link to comment
Share on other sites

David (and others on other forums) who talk about "noise" generated by computers are right. It can be a problem when trying to set up a decent computer audio system. I use a dedicated small media PC for my main listening and it is to my ears "silent" because it connects to my Yamaha AV receiver via optical S/PDIF. I think the optical connection does a great job at transmitting the digital data to the DAC (which is ten metres away from the computer), isolating any "noise" back at the computer.

The computer I mentioned in my post #6 is also a media PC (that's why it has all those audio output options). I just use it for general computing purposes not hifi audio. I do not have PC speakers attached but use headphones connected to the headphone jack if audio is needed. I can hear "noise" through the headphones. When the mouse is moved around the screen that generates noise. The noise must enter the audio chain because the analogue audio circuitry is in such close proximity to all the electromagnetic RF generating computer circuitry. Out of interest, I tried connecting it to a digital AV receiver via the optical connection and it was then "silent". To avoid the noise irritation in my general use of this computer I bought a $10 USB DAC/Headphone amp. The USB cable must help to isolate the "noise" back at the computer, because I am now free from irritating noise.

I, too, was rather surprised that "noise" was not a problem in the DAC comparison article, but it may be that the computer used was of much better quality, such that the Realtek ALC889 onboard chip was able to perform the digital to analogue conversion within the computer noise free..

Link to comment
Share on other sites

I'm not sure what point you are trying to make with your last post. If noise was going to a problem with any of the DACs tested it would have been the onboard Realtek which would have more likely been affected by computer generated noise. Two of the other DACS were connected by USB and the Asus DAC was an internal PC card. The two USB DAC's (like mine) would have been more isolated from the computer. Like I said in my last post maybe the computer used was just a better design/quality than some others (mine included) where you can here noise through a headphone jack. Plus it is unlikely that Asus (or anyone else) would make a PC card DAC if every computer it was to be fitted in suffered from noise.

Yes, all the listening was done on headphones.

Link to comment
Share on other sites

  • 7 months later...
  • 8 months later...

I have been following the “how to properly listen to AR speaker thread” but it has drifted onto TT/Cartridge set up and I am completely focused on digital now.
I am using a dedicated notebook computer for all playback and still satisfactorily using all of the same wireless DACS as before but I am once again looking to acquire an outboard DAC with optical, USB and Coax input.
It is now 4 months since the last post in this thread.
Does anyone here have any recent experience or updates regarding outboard DAC recommendations.

Link to comment
Share on other sites

I have no recommendations to pass on to you, only a bit of knowledge. It is a common belief (amongst techies) that an asynchronous USB DAC is the best way to go. This avoids the necessity for the digital system to constantly re-clock (which it does when S/PDIF digital connections are used).

My limited understanding about this is as follows. When optical or coax S/PDIF connections are used the master "clock" is provided by the device sending the data. The DAC receiving the digital data (say within an AVR) has to constantly re-clock itself to sync with the sending device. When the sending device is a computer the thinking is that the "clock" is not of optimum precision and there may be a more precise clock within the receiving DAC but the overall system's clock is still governed by the sending device. Secondly even if both the sending and receiving clocks are very precise, there is still an amount of re-clocking necessary.

With an asynchronous USB DAC, the USB DAC is the master clock, fetching data through the USB connection as required. There is no re-clocking as the systems master clock is now that within the asynchronous USB DAC.

Whether any difference is audible is another matter but I can see the logic behind the preferred asynchronous USB DAC solution.

Having said all that I am content with my optical S/PDIF connection between my media computer and my Yamaha AV amp.

For me a downside of looking for an alternative "better" asynchronous USB DAC solution is that the analogue output of the DAC (usually around 2V) may not match the input sensitivity of the amp's analogue input (some can be as high 75mV). Clipping may occur. So it may be wise to get an asynchronous USB DAC which is capable of being attenuated to match the input sensitivity of the amp being used. I believe such DAC's with analogue volume control are available.

With a competently designed digital amp or AVR there should be no need to worry about clipping because the full dynamic range within a digital signal from zero (silence) to "all bits lit" (max volume of a digital signal) should always be accepted at the input without clipping.

I know no more on the subject that what I have written here, and suggest you do a bit of research/reading on the internet before parting with any of your hard-earned cash.

Link to comment
Share on other sites

Jeff
Thanks. The good news is my notebook connection will be USB to the prospective DAC. All other DACs will remain wireless and in place. I too am still satisfied with the sound quality of tmy current set up but in the one room where I do any “critical” listening using lossless files I want to avoid the occasional dropout from wireless transmission vagaries.
My concern is that I could purchase a DAC that would be a step down in sound. I don’t need the “best” I just don’t want a sound downgrade. I am looking for an answer in the CSP because of my perception that many of us are more driven by the music than the gear and none of us make a living touting or comparing equipment.

Link to comment
Share on other sites

Happy new Year Adams.

Notebook to DAC via USB is exactly what I have in 2 systems and I like each. As you know, DACs can range significantly in price. I am not sure what the retun is on the expensive options and my guess is that even the lower priced option would not be a weak link in most systems.

I recently picked up my 2nd stand alone DAC, a Music Fidelity VDac II off of Craigs list for $75 and I cant imagine needing anything more. It has Asynchronous USB which seems to be one of the keys to using USB.

In addition to ripped lossless files from CD etc (JRiver), I also do a lot of streaming on Tidal which has higher Res quality that both of my DAC's help deliver to my preamp. Stuff sounds good. My other DAC is an Emotiva and it's plus is that it has a remote with volume control which is a nice way to add that to an otherwise vintage system.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...