Quicktime with Windows Audio Session Option – Am I Bit-Perfect?

[Phil C]

As we know, Quicktime is the engine behind iTunes. Take a look at the latest Quicktime (version 7.6.9). I just installed it on a Win 7 (64bit) pc.

 

Take a look at the “Play Audio Using” menu at Edit>Preferences>QuickTime Preferences>Audio tab. It has three options, Safe Mode (waveOut only), Direct Sound, and Windows Audio Session.

 

My previous Quicktime version didn’t have the Windows Audio Session option, so it must be a new feature. One source said audiophiles have been waiting for this option to enable WASAPI which enables bit-perfect music playback for iTunes on a Win 7 pc. Is this correct?

 

With this new Quicktime, will my 24/96 rez music from HDtracks and also 16/44 rez play bit-perfect? Will it automatically switch resolutions now?

 

Looking forward to hearing your responses, thanks

 

 

iTunes with Win 7 pc > USB cable > Benchmark DAC HDR1

 

[blaine78]

Hi,

 

Quicktime windows audio session, sends the stream without conversion directly from quicktime to windows mixer. with the other 2 methods you had to select a sample rate/bit rate within quicktime before stream sent.

It's not true WASAPI as you still need to select the Bit rate and sample rate within windows mixer for output.

 

If you are playing back 44.1khz files in itunes, use QT windows audio session, select 24/44.1 in windows mixer and have volume on both itunes and windows at 100%, with no Eq, no processing what so ever, this will be bit perfect.

 

 

[Phil C]

Thanks blaine78 for your response. As you advise, I have Windows Audio Session set in QT, sound level set to 100% in Win 7, with no Eq, no processing. By the way, I have also selected in Win7 both Allow Applications To Take Exclusive Control Of This Device and Give Exclusive Mode Applications Priority.

 

I’m still wondering about my 24/96 kHz tracks. Are they playing bit-perfect?

 

Also, I see you are using J River MC16…what file formats are you playing, FLAC, WAV, or other? Are you happy with the tagging?

 

iTunes on Win7 pc> USB cable> Benchmark DAC1 HDR

 

 

[blaine78]

Hi Phil,

If you manually set in windows mixer to 24/96 with volume etc 100%, will be bit perfect for 96khz files.

 

Ah J River. I love it. tagging works great, plays any file you throw at it. There are lots of options, so can be bit daunting at first, but settle in with it, it's very easy to use and stable. it also has WASAPI output, so no need to manually change sample rates in windows mixer. WASAPI sends stream direct from J River to your hardware, bypassing windows mixer altogether. on top of this, sound quality wise, it beats itunes, no competition. If you do decide to use J River, i can give you tips on settings to use for best audio.

 

[JR_Audio]

Under Windows 7 (and Vista), you can not get Quicktime to play Bit True, no matter what you select in Quicktime preferences, also if you select WASAPI.

 

You will notice that with that, you will always see an extra slot named Quicktime under the windows mixer, so even with WASAPI setting, this stream will be mixed.

 

You will notice, that the sample rate will not change automatically and even if you set for the correct sample rate, it will not bit true, because of the windows mixer.

 

JRiver MC on the other hand will be Bit True with WASAPI, WASAPI Event Style, ASIO and with KS out.

 

Juergen

 

[blaine78]

hi Juergen,

you can get bit perfect from suggestions i've mention above from itunes. I've tried and tested with bit checker from Weiss.

 

 

[JR_Audio]

I have done my test some months ago and also one year ago and noticed no difference in failure to get bit true signals. I am on the way for today, so maybe I will check if there is a new version of Quicktime for windows 7 available and will re check this again.

 

One thing I would like to mention is, that the Weiss Bit Checker does use only one static signal. I can cheat the signal with a DSP in thousand ways and would still get the bit true indication with Weiss bit checker. I can for example clip the 8 MSB bits and will still get bit true with Weiss bit checker.

 

But as I told above, I will see if there is a newer version of Quicktime available and will re-check.

 

Juergen

 

[blaine78]

Juergen,

The bit checker to my knowledge is accurate. if i turned down the volume just .1% in j river, the checker knows. So i don't know how you came to this conclusion regarding MSB truncating.

 

[PeterSt]

Under Windows 7 (and Vista), you can not get Quicktime to play Bit True, no matter what you select in Quicktime preferences, also if you select WASAPI

 

Which counts for everything which seemingly is dependend on the setting in Windows itself (like 96 would play back 96 in bit perfect fashion).

 

You better test it like this :

 

Play back 88.2 and set Windows to whatever you like (88.2 is not available). If this plays, you'll at least know that the sample rate converter is in the chain.

 

Sadly, the above doesn't proove it the other way around, like matching the correct sample rate in advance with your playback, will not be bit perfect;

There is no such thing as "nothing will happen" if the sample rate matches. It just doesn't work like that. It needs Exclusive Mode, and *that* can be tested with my 88.2 example above. If that plays (the means is unimportant) it is fairly safe to use 96 just the same.

 

Or "know" the player software well. I said it before, JRiver is no guarantee at all (because it can play in Shared Mode and will do that as soon as it isn't capable of converting herself (for whatever (up to bug) reason)).

Foobar won't allow that, as XXHE will not. They just won't play.

 

Peter

 

PS: I have no judgement about the Weiss regarding its bit perfect indication. I just don't know (because never tested it).

 

PPS: Juergen, I recall from several months back that someone reported something about QuickTime which at least got me thinking that they got their act together. I mean, on being able to play WASAPI/Exclusive.

 

[PeterSt]

Just FYI: This literally means that WASAPI is being used.

 

By itself this doesn't say a thing, because it can be used in Shared Mode just the same. But I guess we know that by know ...

 

Regards,

Peter

 

[PeterSt]

I must apologize. It already suddenly looked to simple to me ...

 

My earlier proposed little test can't work because

 

or Exclusive Mode 88.2 will play (assuming your DAC is capable)

 

or Shared Mode 88.2 will play (into 96 or whatever was selected in Windows) because of the sample rate converter being in the chain.

 

So both will play always.

 

The more dificult way (for most) is looking at some non-ASIO driver control panel which will show you the received sample rate. If you don't have that, there it stops for this kind of "easy checking".

 

Peter

 

[JR_Audio]

If you change the level in JRiver, then you will change everything, so also the LSB Bits, and so Weiss Bit Checker will recognize this.

 

About 6 Months ago, I have tested a ASIO Interface that clipped the MSB Bit. And the Weiss bit checker would not have recognized this.

 

But as I told above, when I am home again, I will look for an more actual Quicktime and will re-check my “older” results.

 

Juergen

 

 

[numberforty1]

So what were the results JR??

 

[JR_Audio]

Under Windows 7 I gave up with testing Quicktime, or iTunes, or Windows Media Player and will not “waste” any more time with testing new versions.

 

Under Windows 7 I normally use JRiver MC or Foobar (as a second verification) and both do work fine with WASAPI Event Style or Kernel Streaming.

 

Juergen

 

[reedermw]

I just ran into something interesting last night that I haven't seen discussed here. In Windows, QT is used to play back the files and I have always set the QT audio output to Windows Audio Session (WASAPI). But there is another option on that same dialog panel called "Music Synthesizer". By default it's set to "QuickTime...". I changed this option to "General Midi" and it dramatically improved the sound. It's less muddy for lack of a better term. I had all but given up on iTunes because the sound quality was lacking but this option seems to make it competitive again. Has anyone run into this before or is it just something unique to my setup? I am running this on a Mac mini running Windows 7 32-bit>USB>Emotiva XDA-1 DAC.

 

[dapla]

I just ran into something interesting last night that I haven't seen discussed here. In Windows, QT is used to play back the files and I have always set the QT audio output to Windows Audio Session (WASAPI). But there is another option on that same dialog panel called "Music Synthesizer". By default it's set to "QuickTime...". I changed this option to "General Midi" and it dramatically improved the sound. It's less muddy for lack of a better term. I had all but given up on iTunes because the sound quality was lacking but this option seems to make it competitive again. Has anyone run into this before or is it just something unique to my setup? I am running this on a Mac mini running Windows 7 32-bit>USB>Emotiva XDA-1 DAC.

 

Just recently (now four years after the quoted post) I tried these settings and couldn't reliably tell a difference in SQ listening to selections from a few tracks on a fairly high resolution 2ch rig, but I tend to repeat such "testing" so we'll see. I left it in "general midi." My understanding had been that the settings only mattered when related to the actual use of a midi, but this is where my lack of PC savvy can trip me up.

 

I'm really in the thread because Windows X referred me to it. I found my WAS "exclusive" setting in QuickTime Preferences seems to be "shared" after all. As still a noob in CA (very much a vet in non-PC based 2ch systems) I'm not sure there's a "final answer" in the thread on the bit-perfect part (and it has been years since the last post), but certainly the shared thing still happens.

 

Also discussed in this thread and elsewhere, is the matter of setting software volume levels on OS and itunes or streaming radio apps to 100% and using any playback volume adjustments in hardware to be bit-perfect, I did find this interesting exchange below (also several years old) and would love any feedback from the CA veterans. Is it still set all software to 100%?

 

In my system it's better if I can use the windows mixer or itunes volume, but I always want to know what affects SQ and to what degree. I am trying to get the best out of my itunes for a couple more months as other CA-related purchases are currently ahead of playback software improvement and foobar appears complicated to set up. My eyes are on Fidelizer first, then HQ Player, or if DSD and that level of "flying" seems not worth it to me, JRiver as a "safe" move that's still a real step up.

 

audio - From a quality perspective, what is better: turning volume up in the software, in the OS, or on the speakers? - Super User