Beginner DAC questions
Dec 30, 2013 at 6:06 PM Thread Starter Post #1 of 36

NickMDal

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Hi.  My wife and I love classical.  We have ripped our CD collection losslessly (by WMP) saved to PC and listen mostly through computer, frequently by a pair of Grados.
 
Will a DAC improve our sound if I listen to the lossless copies as they are?
 
We bought a DacMagic Plus (using 2.0 driver) thinking so but are not seeing much of a difference.  I use foobar with the ASIO and kernel plugins.  The unit only reports 44,1 sampling and so it seems playback shouldn't be hugely different.  Should the sampling rate by the unit be showing higher?  Foobar has a sampling rate adjuster that does not affect the DacMagic sampling rate.
 
The computer motherboards all claim to have HD audio components, though not sure if that is reflected in quality of digital to analog conversion (without the DAC).  Do those chips make 44.1 sound quite good with good headphones?
 
Do the CDs need to be reripped at a higher sampling rate in order to get the DacMagic to sample at a higher rate?  Thanks!
 
Dec 30, 2013 at 8:41 PM Post #2 of 36
DACs on computer motherboards, no matter how good, will always be infected with digital noise due to all the processing going on. So really there's no point in putting anything half decent on the mobo itself. There's no technical advantage, only disadvantage to upsampling CDs to a higher rate. That's not to say it couldn't sound better though, if it does that's just a sign that the DAC's corrupting the sound more at the lower rate.
 
As you like classical (I'm also a huge classical fan) I'd suggest looking at getting a DAC based on a multibit chip (say TDA1543, AD1865, TDA1545) - these deliver a more believable instrumental timbre - on brass particularly, but also piano. Your DACmagic has a sigma-delta type chip and they're far more common these days.
 
Dec 30, 2013 at 10:21 PM Post #3 of 36
Thanks for the help.  I'm still a little confused.  The DacMagic Plus lists 24 bit dual DACs.  Isn't that multibit?
 
If the CD is not sampled at a rate higher than 44.1, how can anything improve it other than by providing a cleaner signal to headphones (mobo noise)?
 
If the lossless rips are good quality, it would seem pointless to resample it higher.  Is that why you said there was no technical advantage?
 
The Cambridge Audio DacMagic cost $500 and used to sell for 650.  How might that vibe with the units you mentioned that seem to be a fraction of the cost?  Cambridge Audio sold a ton of those.
 
This next is due to my ignorance of this area.  Are there consumer versions of any of your suggested units?  I am in favor of cheaper and really just want to hear everything there is on our Ludwig collection CDs 
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We have a budget of 500 and the unit can be returned.  May I ask what you or anyone else would do?  Thanks for your advice with this.
 
Dec 30, 2013 at 10:48 PM Post #4 of 36
Good questions - the one about '24bits' is a common misunderstanding and its not helped by the manufacturers of parts playing the numbers game.
 
First off, '24bits' here just refers to how many bits its input will recognise. Whereas 'multibit' refers to a way of building DAC chips - if you pull up the datasheet for the chips inside your Dacmagic you'll see that inside they use a 'low bit' (typically 5 or 6 bits) DAC and digital processing before it to correct for all the noise such DACs generate. Problem is, not all the noise is corrected. By 'multibit' I meant 16bits - the same width DAC as your digital audio files have so no processing is needed between the audio file and the actual DAC.
 
Second, about 44k1 - its perfectly adequate for very decent sound, provided you convert it with a decent DAC. No need to go higher (in rate) or deeper (in bits) despite what the purveyors of 'hi-res' will tell you.
 
As regards whether to return your DACmagic - I'd not suggest that yet. But do go out and find a multibit DAC to audition and see if you notice greater listening satisfaction with it. If not, you'll save yourself a lot of hassle.
 
As for consumer versions of multibit DACs, there isn't a very wide choice. One that comes to mind which is cheap is the Muse 4 * TDA1543. Another is the Lite DAC-AH. Metrum Octave is another but its not as cheap as the other two.
 
Dec 30, 2013 at 11:35 PM Post #5 of 36
That's really helpful.  With a 500 budget and the fact that we are using SR80s, do you think we would get a better return on headphone upgrade (need 2)?  Read that going up the Grado scale (a bit) won't yield much.
 
Guess we could ditch the laptop playback and go through the AV Receiver (Consumer Onkyo TX SR505, that does everything), as we have been.  Not sure about it's DAC or headphone amp.  Nothing it its specs.
 
Can you recommend a cheapo (<150) small dac for the laptop that would at least eliminate the laptop noise and produce a fair rendition of the lossless wmv file?  Even with the DAC, the laptop produced strange pauses in the music.  The CD drive?  Thanks again.  Glad I stopped by here. 
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Dec 31, 2013 at 2:05 AM Post #6 of 36
First some context - I'm a DIYer and I tend not to use anything in stock form, I'm always modding. But given that, I'd say your money's best spent on better electronics rather than more expensive headphones. Note that better does not always mean more expensive in electronics. With a DIY mentality its possible to do way, way better for much much less money than commercially available electronics.
 
When you say 'taptop noise' do you mean you can hear processing breakthrough on your audio? If so, is this when using the laptop on batteries too? The only sure-fire way to eliminate common-mode noise (that's noise you get when plugged into the mains which disappears on battery) is to go optical, There are fairly cheap USB-S/PDIF converters (<$30) which have optical (Toslink) outs. Then you need a DAC with an optical in - both the Muse and Lite DACs I mentioned have that. This is sure to cure common-mode woes - you'll get more jitter due to the optical connection but in general multibit converters are more immune to jitter, subjectively. I'm not sure how to advise on the 'strange pauses' - could be your laptop's underpowered CPU-wise? Just speculating though.
 
Dec 31, 2013 at 11:38 AM Post #7 of 36
 
If the CD is not sampled at a rate higher than 44.1, how can anything improve it other than by providing a cleaner signal to headphones (mobo noise)?
 
If the lossless rips are good quality, it would seem pointless to resample it higher. 

 
Upsampling 44.1 kHz data by a non-integer multiple to, say, 192 kHz involves an interpolation step, so you won't get back the data that you put in. However, this also allows the use of a slow rolloff filter with less 'ringing' in the impulse response which some claim to be advantageous in terms of sound quality.
 
I would hesitate to judge a DAC simply on the basis of its digital architecture alone. Multi-bit ladder DACs can suffer from noise generated by drifting resistor values due to thermal loading and manufacturing tolerances (so I've read), however I'm unsure how the noise is distributed (I'm no digital expert) and I can't say for certain that I've ever listened to a true ladder DAC. Although Sapientiam eschews delta-sigma modulation, the current industry darling, the ESS Sabre32 Reference series DAC, bases its design on delta-sigma modulation with some noise-shaping tricks that they claim result in better sound. A presentation on the ESS Sabre DAC can be found here - http://www.esstech.com/pdf/noise-shaping-sigma-delta.pdf.
 
With respect to jitter, if you use a USB DAC that receives the data in asynchronous mode (e.g. DACs employing Wavelength Audio's Streamlength technology), it is largely immune to jitter as the data rate is controlled by the DAC and not the PC. The chief concern here is that your playback process receives a high enough priority within your OS that it isn't constantly interrupted by other running programs - this can result in drop outs and clicks / pops.
 
For a general introduction on how digital playback works, see:
 
http://xiph.org/video/vid1.shtml
http://www.xiph.org/video/vid2.shtml
 
For more on delta-sigma modulation, see:
 
http://www.ti.com/general/docs/lit/getliterature.tsp?baseLiteratureNumber=slyt438&fileType=pdf
http://www.ti.com/lit/an/slyt438/slyt438.pdf
 
For an interesting experiment on digital filtering, see:
 
http://www.stereophile.com/reference/106ringing/index.html
 
Jan 1, 2014 at 7:40 AM Post #8 of 36
   
 
Will a DAC improve our sound if I listen to the lossless copies as they are?
 
We bought a DacMagic Plus (using 2.0 driver) thinking so but are not seeing much of a difference. 

The DacMagic is a good Dac. Do you compare with the computers headphone output? If that is the case, I'd look at the rest of the chain. There must be something wrong. Unless you put special boards into the computer, the DacMagic should show a clear improvement in sound quality.
 
Though I don't know the SR 80, I'd expect, this is the weak link.
Couldn't you try to borrow a good pair of headphones from a dealer over the weekend and check with better headphones?
 
Jan 1, 2014 at 11:20 AM Post #9 of 36
Trust your own ears rather than the prejudices of random strangers.
 
You are right. There is no reason to believe audio via the DacMagic will sound any different to a correctly configured, fully functional, modern on board solution. It might measure very, very slightly better in a test lab situation but both are beyond the ability of the average human auditory system to differentiate. Even if you could the difference would be so small as to be insignificant.
 
You will fnd the best value route to better audio is to spend on better headphones.
 
Jan 1, 2014 at 12:27 PM Post #10 of 36
Agree that the MB based DACs are getting ever better.  There is a pretty good one on the PC I tested with and so there was no easily detectable difference.  The SR80s are Grados and already produce excellent sound.
 
Guess I was thinking it was possible to relive the sound produce by my old Sony D-555.  Problem is I don't have 29 year old ears anymore 
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In 1990, I was pretty broke when my reserve unit became activated for Desert Storm.  Somehow that became my justification to spend 400 on the Sony and another 130 on matching Sony digital headphones.  God what a sound!!!  My love for Ludwig's music instantly became an obsession!
 
Is it really that I had much better ears then?  Now at 52 (normal hearing) and with Grado SR80s and lossless CD rips, am I far from what I heard 23 years ago?
 
Jan 1, 2014 at 2:56 PM Post #12 of 36
  Thats a good joke to begin the year with.

Its not a joke, people buying blind on others recommendations and advice is the joke that is VERY common on this site.  Also modern motherboards are designed with audio in mind as many people now use their pc for a home media server and the producers are very aware of the fact. Things have moved on a great deal in the last 5 years.  Advising people to buy a $300 DAC to go with $200 headphones is madness and it happens all the time on head-fi. 
 
Jan 1, 2014 at 5:31 PM Post #13 of 36
  Its not a joke, people buying blind on others recommendations and advice is the joke that is VERY common on this site.  Also modern motherboards are designed with audio in mind as many people now use their pc for a home media server and the producers are very aware of the fact. Things have moved on a great deal in the last 5 years.  Advising people to buy a $300 DAC to go with $200 headphones is madness and it happens all the time on head-fi. 


Well, the joke is that a total stranger (RonaldDumsfeld) tells a total stranger (NickMDal) not to trust the advice of total strangers (probably my advice, but most likely everybody elses too). And that in an internationally read internet forum, where 99.99% are total strangers. If you ask for advice here, you certainly get it from total strangers by design.
 
That is funny indeed, isn't it? Made my day. My wife is still rofl.
 
Jan 1, 2014 at 7:24 PM Post #14 of 36
Sage advice from a stranger can only be good.  I returned the DAC and got my $540.00 back.  Whew!  Thanks for pointing me in the right direction.  That is the most helpful advice someone can receive.
 
Jan 1, 2014 at 7:40 PM Post #15 of 36
  Also modern motherboards are designed with audio in mind as many people now use their pc for a home media server and the producers are very aware of the fact. Things have moved on a great deal in the last 5 years.

 
Is there any evidence for this claim that mobos are designed 'with audio in mind?.Certainly some mobos I've encountered have Toslink outputs - is this a sign they were thinking about audio?
 

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