KeithL
Administrator
Posts: 9,941
|
Post by KeithL on Dec 16, 2012 12:25:57 GMT -5
I decided to give this its own post The "best" way to control your volume (for absolute best quality) is different depending on what DAC you have. The XDA-2 has an analog volume control, so the volume control itself doesn't change the sound quality no matter where you set it. If you happen to have an amplifier (or use a preamp) which has its own volume control, you can set the XDA-2 volume wherever it is convenient. In general, if you have multiple volume controls, you always want to keep the volume controls on everything set sort of in the middle (you don't want to set one to 95% and the other at 5%). (If you have a preamp with an analog control that uses a potentiometer, you may want to keep it ABOVE the bottom quarter of it's travel, since some potentiometers don't have especially good channel tracking at very low settings - and the volume control on the XDA-2 tracks virtually perfectly at ANY setting). The XDA-1 has a digital volume control, so the volume control on the XDA-1 WORKS by reducing the actual numbers in the digital audio signal. Another way of stating this is that it reduces the resolution of the audio at lower volume levels. (The quieter sounds on a CD also use less bits than the louder ones; smaller numbers simply take less digits to store). This means that, if your amplifier has its own volume control (and probably also gain), then you want to keep the XDA-1 set to maximum (80), and always use the volume control on the amp, for absolute best sound quality. If the amp doesn't have a volume control, then using the one on the XDA-1 isn't especially bad - it's just the second-bast option. Some people hear the difference when it's turned way down and others don't; when it's turned way down, it's playing pretty quietly, and you may not notice a slight reduction in resolution; just like you don't notice a reduction in quality during the quiet spots on a CD. If your amplifier doesn't have a volume control, but has lots of gain (so you never get the XDA-1 up past 10, even when it's playing as loud as you ever go), you may get a slight improvement in sound quality if you add a pair of passive attenuators between the XDA-1 and your amplifier. This will cut down on the signal level a bit, so you will be able to operate the XDA-1 with the volume control set higher, which will make a slight (but possibly audible) improvement in the sound. You can get a pair of 12 dB passive attenuators at Parts Express for about $30 (they won't adversely affect the sound, just reduce the level slightly).
|
|
KeithL
Administrator
Posts: 9,941
|
Post by KeithL on Dec 23, 2012 15:36:57 GMT -5
I actually have a Squeezebox Touch. I don't use it much since I switched over to just using a laptop connected to a DAC, and I haven't tried any of the output enhancements, but I do sort of follow the threads. As long as the UAC2 support is standard, I would expect it to work. Many DAC drivers are specifically written to only work with certain hardware, but that is a vendor choice - UAC2 itself is a standard and any driver not specifically limited should work with any UAC2 device. Since we do use the CM6631 USB chip, look particularly for anybody who has tips to get it to work with that. I am a little bit curious, though, why you would want to use USB with the SBT and our XDA-2. The SBT has a Toslink and a Coax output. It seems easier to just use the Coax output, which doesn't need any mods or special drivers. I was under the impression that most folks were only using the USB output because they had a USB-only DAC they wanted to connect. Hello and welcome, yesterday my XDA-2 arrived:) Did anybody now if there is any chance to let it work with USB and a Squeezebox touch with "Triodes Enhanced Digital Output app" Thanks
|
|
KeithL
Administrator
Posts: 9,941
|
Post by KeithL on Dec 23, 2012 16:02:18 GMT -5
There is no restriction about putting hi-res audio OUT over HDMI. Just like any other hardware Blu-Ray player, your computer is allowed to send OUT hi-res audio over HDMI. (And it can do that regardless of whether it got it from a Blu-Ray disc or a file.) The whole copyright thing with HDMI relates to not being allowed to take hi-res audio that came IN over HDMI and send it out some other way. Any HDMI device is allowed to pass along high-res audio over an HDMI output - because HDMI itself is considered to be "secure". Where the limitation arises is that equipment with HDMI inputs is not allowed to take in high-res through HDMI, and then put it out over a different format - like Coax - in hi-res. The reason is that they're afraid you'll send that output to a recorder, and so then be able to record that hi-res audio at full quality (which is the no-no). So, for example, an Oppo is allowed to play a Blu-Ray disc and output high-res audio over HDMI; likewise, the new ones could take in high-res audio over HDMI and put it back out ALSO OVER HDMI - "secure in to secure out". They can also decode that audio and put out analog audio (which is NOT a high-res output format). What they're NOT supposed to do, for example, is take in high-res audio over HDMI and then put it out over Coax. (Because, since Coax isn't "a secure connection", you could possibly record it in a high-res format.) So that Coax OUTPUT is going to be limited to 24/48. They can also take hi-res audio from some other source and send it out over HDMI ("insecure in to secure out" - so who cares.) The whole point is that you are NOT supposed to be able to get the high-res digital audio out of the "HDMI signal chain" and to some sort of output you could plug into a recorder. In the old days there was some wiggle room in that not all content HAD to be protected this way, but I believe that the current HDMI and Blu-Ray standards now make it mandatory. I am told that there are still some older models of various brands of hardware players, made before the newer standards, that simply ignore the restriction... but I don't know any particulars there. (Likewise, there is software available that will let you decrypt and dissect a Blu-Ray disc, and so get the hi-res audio directly - but it is, of course, illegal to use.) I would assume that most modern big-brand software Blu-Ray players comply with the restrictions - and act just like a hardware player. (For others, especially those sold from foreign countries, your guess is as good as mine.) My Asus does output audio & video thru it's HDMI out. Just to make sure I understand you are you saying that because of copyright protection you get approximately 24/48 through HDMI out of a computer to the Oppo's HDMI in, or a pre/pro's HDMI in, whereas with a USB/Coax/Optical DAC 24/192 is achievable? I don't believe that is correct. My Acer laptop as well as my HP desktop before it outputs the full resolution of my HD audio files(up to 96/24) using JRiver Media Center via HDMI output. If HDMI output were limited to 24/48, then you could never play DTS-HD Master or Dolby TrueHD audio out when playing a Blu-ray disc. I specifically use HDMI output from my computer to my Denon 4311 AVR since that way I am assured of getting the full resolution of my audio files to the onboard DAC in the AVR. I hope this helps.
|
|
|
Post by jevans64 on Jan 2, 2013 0:28:45 GMT -5
I will be the first to admit that I have little knowledge about DAC's. But why is it that DAC's only have USB, Coax, or Optical options? With all the computers that are out now with HDMI you would think that there would be DAC's with an HDMI port. I bought an ASUS net book solely for the purpose of streaming music and movies. It works great! When I get an Oppo BDP-103 I am hoping to be able to go from HDMI out on the Asus to the HDMI in on the Oppo to take advantage of the Oppo's DAC. Is there anything wrong with this scenario? Will this even work? Not sure if this will help you but maybe it is a glimmer of hope. I normally pump everything through my receiver since the DACs in it are high quality Burr-brown vs. whatever is in my Oppo BDP-103. I have an Asus Transformer TF700T tablet and use an MHL cable to connect it to my receiver. The only audio file I have is a 48k 2.0 Flac. I unplugged the MHL cable from the receiver and connected it to the front MHL port and switched the Oppo to MHL HDMI. My HD movie trailers show up as 7.1 HD MA and the 2.0ch Flac file shows up as it should, just like it would through the receiver. I was using the Android version of Dice Player. Haven't tried BS Player yet. The built-in audio player worked as well. I don't have any high resolution audio files handy unless I rip them from my collection. I can check if there is a demo track or something I can torrent.
|
|
kml
Sensei
King o' lamp cord
Posts: 235
|
Post by kml on Jan 2, 2013 11:31:37 GMT -5
|
|
|
Post by garym on Jan 25, 2013 12:02:35 GMT -5
For its next iteration of the XDA Emotiva needs to add DSD support (direct conversion to analog, with no intervening PCM step), and DLNA capability. When it does I'll buy one. :-)
|
|
|
Post by kaijorg on Jan 29, 2013 12:35:18 GMT -5
I am considering the xda2. What is the best connection to use to get files from my computer. I am not familiar with some of the options. I have Mac & PC. Also is there a good way to do wireless or better to connect directly?
|
|
|
Post by AudioHTIT on Jan 29, 2013 20:49:34 GMT -5
I am considering the xda2. What is the best connection to use to get files from my computer. I am not familiar with some of the options. I have Mac & PC. Also is there a good way to do wireless or better to connect directly? With a Mac I like TOSLink, but some prefer USB. If you're not aware the headphone jack will accept a mini-TOSLink connector which you can plug into the XDA-2's optical in with a cable like this. www.monoprice.com/products/product.asp?c_id=102&cp_id=10229&cs_id=1022902&p_id=1557&seq=1&format=2With a PC it depends on the outputs available, most use USB but if your board supports it coax and TOSLink also work. With a Mac you can easily do wireless with AppleTV or Airport Express. They are limited to 16/48 and 16/44 bitrates respectively so if your files are mostly ripped CDs then these work fine, but they won't do HD audio like the direct options.
|
|
|
Post by yves on Feb 2, 2013 6:23:51 GMT -5
Most PC motherboards (as well as many PC laptops) have been supporting mini-Toslink already for ages, but many people seem to just not know it yet. In a modern PC, the most commonly found onboard audio probably is Realtek HD Audio. Assuming that's what your PC has, go to your Realtek HD Audio configuration panel. In the column to the right, if you see a title called "DIGITAL" then, below it, you should see an image of a digital output connector (use the vertical scrollbar on the right side of the panel, if any).
So if it clearly shows that you have a digital output and you are still unable to find a hole to plug your digital cable into, it's probably because a mini-Toslink connector will be hidden inside an analog line out 35 mm jack hole (probably the green colored one). Typically, the user manual doesn't say that it's a multi-functional 35 mm jack hole that can support both analog line out and optical out, simply depending on whether you plug in an analog 35 mm jack or an optical 35 mm mini-Toslink jack.
The typical reason why some (or many) people prefer to use an internal PCI or PCIe expansion card, like an ASUS Xonar Essence ST or STX soundcard, for example, just to use the S/PDIF output connector on it and not the analog outputs on it, is NOT because their motherboard doesn't have any onboard S/PDIF, but simply because onboard S/PDIF usually has very crappy jitter performance. Whereas, on a decent add-in soundcard, the electronic components (including the ones that make up the S/PDIF output) are supposed to be of higher quality than the onboard audio components of a computer motherboard, which results in much better jitter performance of the S/PDIF output from the computer to a DAC.
However, even the best of the best S/PDIF output connectors, whether they be optical or coax, still have jitter in them. Some experts who have measured the jitter performance of various digital outputs say coax is better than optical in this regard. However, coax can conduct the electric noise coming from the computer's hardware components, into the internal circuitry of a DAC. This explains why some people prefer to use an external USB-to-S/PDIF adapter (which can get very expensive), hoping to minimize the jitter problem as well as the noise isolation problem.
So let's talk about USB DACs. There exist three different types of USB DAC inputs.
Isosynchronous USB has the worst jitter performance of them all, at least in theory. This is because the master clock in the transmitter (in the computer or in the digital-to-digital adapter / transport) will ignore the slave clock in the DAC, so the clock in the DAC is constantly being adjusted (synchronized) to match the master clock.
With isosynchronous USB, the transmitter does not send a separate timing signal, so the receiver has to derive the timing information from the received musical data, which is received in a jittery fashion so that the receiver has to apply jitter correction (based on the derived information). This technique is a relatively very primitive one, and it is completely similar to S/PDIF because the main culprit here is the receiver cannot report back to the transmitter (both isosynchronous USB and S/PDIF are one-way communications).
Adaptive USB partially solves the jitter problem because it uses a two-way communication, allowing the receiver to basically tell the transmitter to slow down or hurry up.
Asynchronous is the new buzzword. Asynchronous USB implements a memory buffer between both clocks, allowing the master clock to be placed on the inside of the DAC unit instead of on the outside, thereby eliminating all transport jitter. The DAC itself still has jitter, though (in fact, all DACs have jitter). It is not easy IMO to find a very good, affordable DAC that uses asynchronous USB. Most are still having problems with electric noise coming from the computer's hardware, AFAIK due to their USB interface using improper galvanic isolation.
|
|
|
Post by jackfish on Feb 2, 2013 8:00:44 GMT -5
It is not easy IMO to find a very good, affordable DAC that uses asynchronous USB. Schiit Modi for $99.
|
|
|
Post by garbulky on Feb 2, 2013 9:01:39 GMT -5
The typical reason why some (or many) people prefer to use an internal PCI or PCIe expansion card, like an ASUS Xonar Essence ST or STX soundcard, for example, just to use the S/PDIF output connector on it and not the analog outputs on it, is NOT because their motherboard doesn't have any onboard S/PDIF, but simply because onboard S/PDIF usually has very crappy jitter performance. Whereas, on a decent add-in soundcard, the electronic components (including the ones that make up the S/PDIF output) are supposed to be of higher quality than the onboard audio components of a computer motherboard, which results in much better jitter performance of the S/PDIF output from the computer to a DAC. I've talked quite a lot on here about there should be no difference in sound quality as long as the output is properly configured to send out a bit perfect signal. I've recommended people buy the cheapest cd player possible. But cautious initial impressions show me that I may have to eat my words. ;D I've been using an asus xonar essence st's SPDIF coax->XDA-1 and from the brief time I've had with it, I've noticed a nice difference which really surprised me. I was mainly excited about the xonar SPDIF out ASIO vs my USB (WASAPI) on my laptop out because it would finally allow the xda-1 to play high res audio. And it did flawlessly. But, there was a difference - at least on just a few hours of listening - and so far it has been very nice. The essence ST has a feature that the STX doesn't have which is an onboard jitter reduction/correction clock. I don't know if the benefits are transferred to the spdif output but it may be accounting for the difference. Interestingly I noticed no difference between a Toshiba HD-DVD A-2 toslink output vs the laptop via USB. However the coax output of the xonar essence to the xda-1 sounded better than all of them including a ps3 via toslink. Unfortunately the essence has some issues with ASIO on windows XP and so I am hesitant right now to claim it's a definite improvement as I'm not sure if there is something else mucking around there that makes me notice a "difference". So I'll reserve my final opinion on that following further testing. But, yes, I am very excited about this unexpected "free" improvement that I never utilized.
|
|
|
Post by tbro49 on Feb 2, 2013 9:15:33 GMT -5
Yves, I have Realtek HD Audio with a coax output set for 24/192 output to my UMC-1, which indicates that is what it is receiving. It sounds pretty good, especially in the bass, but a bit tinty/harsh on the high end. Is there something else I should be doing to maximize the SQ?
|
|
|
Post by garbulky on Feb 2, 2013 9:18:13 GMT -5
tbro sending you a pm
|
|
|
Post by yves on Feb 2, 2013 9:53:42 GMT -5
It is not easy IMO to find a very good, affordable DAC that uses asynchronous USB. Schiit Modi for $99. Personally, I, would not describe the sound of a Schiit Modi as "very good"...
|
|
|
Post by yves on Feb 2, 2013 10:44:34 GMT -5
I've talked quite a lot on here about there should be no difference in sound quality as long as the output is properly configured to send out a bit perfect signal. I've recommended people buy the cheapest cd player possible. But cautious initial impressions show me that I may have to eat my words. ;D I've been using an asus xonar essence st's SPDIF coax->XDA-1 and from the brief time I've had with it, I've noticed a nice difference which really surprised me. I was mainly excited about the xonar SPDIF out ASIO vs my USB (WASAPI) on my laptop out because it would finally allow the xda-1 to play high res audio. And it did flawlessly. But, there was a difference - at least on just a few hours of listening - and so far it has been very nice. The essence ST has a feature that the STX doesn't have which is an onboard jitter reduction/correction clock. I don't know if the benefits are transferred to the spdif output but it may be accounting for the difference. Interestingly I noticed no difference between a Toshiba HD-DVD A-2 toslink output vs the laptop via USB. However the coax output of the xonar essence to the xda-1 sounded better than all of them including a ps3 via toslink. Unfortunately the essence has some issues with ASIO on windows XP and so I am hesitant right now to claim it's a definite improvement as I'm not sure if there is something else mucking around there that makes me notice a "difference". So I'll reserve my final opinion on that following further testing. But, yes, I am very excited about this unexpected "free" improvement that I never utilized. I find that the one best way to discover audible differences (without professionally training one's hearing in an attempt to become the "golden ear" type of person) is to focus on the music and nothing but the music. As soon as I try to focus on the differences instead of on the music itself, clearly audible differences tend to become alot more subtle and I often stop hearing differences altogether. If I use fast A/B switching, the audible magnitude of differences is affected similarly. Initial impressions can be VERY deceiving. It often strikes me that I do not seem to be noticing a difference and then suddenly, I realize that I have a completely different emotional connection with the music. These differences in the emotional response of the music listener to the music itself are not at all easy to describe, yet can sometimes grow from unaware / virtually nonexistent to overwhelmingly obvious just by trying to enjoy the music for days, weeks, even months without changing anything whatsoever to the setup (and instead, simply allowing one's ears to adapt to the sound signature). As a final example, some people prefer bright sound. It is only after they have listened to neutral sound and nothing but neutral sound for two whole months, they will usually discover the fact brightness can easily be misinterpreted as detail, when in reality, brightness was killing a fairly big portion of the real detail. However, not every person's hearing is the same (!), so the term "neutral" varies from person to person (even, if it were technically materially possible to eliminate a human person's personal preferences completely from the equation). I hope this illustrates why audio is part science, part subjectiveness.
|
|
|
Post by yves on Feb 2, 2013 11:19:39 GMT -5
Yves, I have Realtek HD Audio with a coax output set for 24/192 output to my UMC-1, which indicates that is what it is receiving. It sounds pretty good, especially in the bass, but a bit tinty/harsh on the high end. Is there something else I should be doing to maximize the SQ? Perhaps you could try using a HDMI source, just to see if that changes anything (I am not familiar with the UMC-1, sorry about that). If your PC has a HDMI output connector, chances are good your vidcard supports audio "bitstreaming" over HDMI. I know Keith mentioned (earlier in the thread) something about ATI / AMD vidcards giving you better luck at this, but the very latest (as well as one or two somewhat older exceptions that I can't remember which, but I do know the GTX 570 and the GTX 580 can't) NVIDIA vidcards can do it too, and so can the latest Intel integrated graphics stuff (my new laptop has Intel HD 4000).
|
|
DYohn
Emo VIPs
Posts: 18,348
|
Post by DYohn on Feb 2, 2013 11:21:59 GMT -5
|
|
|
Post by tbro49 on Feb 2, 2013 12:02:03 GMT -5
Yves thanks. With help from Garbulky, I enabled WASAPI for Mediamonkey and the sound seems improved upon initial listening at low volume. I do not have hdmi capability on my computer.
|
|
|
Post by yves on Feb 2, 2013 13:05:29 GMT -5
Could be, but the designer of the ODAC (NwAvGuy) sure has been making alot of bold statements re objective versus subjective. According to him, his goal was to design a DAC that could compete against the Benchmark DAC-1; however, the sound of the Benchmark DAC-1 leaves me literally stone cold.
|
|
|
Post by newguru on Feb 7, 2013 9:44:28 GMT -5
I am a little bit curious, though, why you would want to use USB with the SBT and our XDA-2. The SBT has a Toslink and a Coax output. It seems easier to just use the Coax output, which doesn't need any mods or special drivers. I was under the impression that most folks were only using the USB output because they had a USB-only DAC they wanted to connect. I can tell you why I run this setup. You can now install a simple third party app ("Enhanced Digital Output") developed by Triode that allows your Touch to output true 24/192 to your DAC via USB or Coax SPDIF. You need the latest updated Media Server 7.2 installed first. It installs a linux kernal that enables the high res digital output and disables the analog outputs (which you don't need if using a DAC anyway). I installed in a few minutes and can attest that it does improve the overall sound quality. My setup actually runs from a Synology DS1512+ running the Logitech Media Server (service on the Synology) to the SBT to a Wyred4Sound µLINK USB to S/PDIF converter (asynchronous XMOS design which is driverless; just plug and use) and then into the Emotiva XDA-2 -> out to my Denon (for the next week or two only) and out to the XPA-5 but eventually the XDA-2 signal will be sent balanced out to the Emotiva XSP-1 and then balanced out to the Emotiva XPA-5 (2 channels of it balanced with the other 3 unbalanced from my Denon 3312CI). I have a good amount of music that has been converted from vinyl to 96 and 192K audio as well as a bunch of HDtracks high resolution audio on the Synology that I need this setup to play high resolution through. I run the XDA-2 in two modes: one with the ASRC enabled if I'm listening to standard CD quality FLAC files since it upconverting to 96K is desirable in that case and when listening to true 96 or 192K files with the ASRC in bypass mode as I don't want any conversion happening in that scenario. Best of both worlds for me. I get the jitter reduction for the high resolution music with the µLINK USB to S/PDIF converter on my true 96K and 192K FLAC files and for CD stuff I get to still utilize the Emotiva's upconversion technology as well. Incidentally I do prefer the sound of the normal 44.1K CD stuff with the ASRC enabled over ASRC in bypass mode. To my ears, it does sound better on the 44.1K stuff.
|
|