Windows 10 generates a 13dB increase in noise & distortion when going from Windows output level 99 to 100. I am posting Audio Precision APx555B analyses to illustrate.
This anomaly was verified in two ways: 1) USB to I2S to APx555B DSIO digital input, 2) USB to ASIO to Yamaha A-S801 headphone out to unbalanced APx555B analog input. The latter is illustrated.
THD+N (ratio) goes from -94dB @Windows 99 level out to -81dB @Windows 100 level out.
This bug is likely to be encountered, even by Audio professionals, because it is well known that audio quality is optimized by generating maximal digital levels out of a PC; i.e, controlling volume on a downstream analog audio amplifier.
This anomaly was verified in two ways: 1) USB to I2S to APx555B DSIO digital input, 2) USB to ASIO to Yamaha A-S801 headphone out to unbalanced APx555B analog input. The latter is illustrated.
THD+N (ratio) goes from -94dB @Windows 99 level out to -81dB @Windows 100 level out.
This bug is likely to be encountered, even by Audio professionals, because it is well known that audio quality is optimized by generating maximal digital levels out of a PC; i.e, controlling volume on a downstream analog audio amplifier.
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Welcome to the forums, and thanks for the grunt work.
Audio professionals mostly use ASIO. That is unaffected by Windows Volume control position.
Also, most audio interfaces meant for professional use (though not all) come with hardware mixers that link to the Windows VC without actually routing it through the software control mixer built into Windows.
And lastly, some interfaces interpret the VC position differently from others. For example, the first generation Audioquest Dragonfly used some of the positions for adding digital gain, which would drive the unit into clipping. This was in spite of the device having its own analog volume controller. It was recommended to run the Dragonfly between 90 and 93 position and no further.
So there happen to be multiple variations on the theme, and experimentation is the key.
Audio professionals mostly use ASIO. That is unaffected by Windows Volume control position.
Also, most audio interfaces meant for professional use (though not all) come with hardware mixers that link to the Windows VC without actually routing it through the software control mixer built into Windows.
And lastly, some interfaces interpret the VC position differently from others. For example, the first generation Audioquest Dragonfly used some of the positions for adding digital gain, which would drive the unit into clipping. This was in spite of the device having its own analog volume controller. It was recommended to run the Dragonfly between 90 and 93 position and no further.
So there happen to be multiple variations on the theme, and experimentation is the key.
Posted images are too big.
Can you please tell me how to reduce size.
Media Manager was not apparent.
Can you please tell me how to reduce size.
Media Manager was not apparent.
IMO measurements from the first fully-digital path would show what really happens with the digital signal in windows. The latter path could have involved Yamaha internal distortions at full scale input signal.
Windows audio has two major problems that aren`t very well understood, but need to be managed to avoid distortion. Once these are taken care of, it can be fantastic.
My detailed investigation and measurements are attached, but summarizing:
1. Avoid Windows`CAudioLimiter by ensuring signal never exceeds -0.12 dBFS. This requires:
a. Adding ~ 4 dB digital loss (pre-amp APO) if upsampling, to avoid intersample overs (see Benchmark site for detailed description)
b. If not oversampling, adding loss (I use 4 dB) if high pass filtering which can cause the maximum digital word to exceed the unfiltered maximum value
c. otherwise add at least 0.2 dB pre-amp APO loss even if not filtering or upsampling
2. Checking your system for `hidden`APO`s that can create distortion, and then disabling them (eg, using EAPO). My Dell tower had an APO that I believe to be related to the stock realtek card that caused terrible distortion similar to the OP`s, until it was disabled. `Disable all sound effects`in the enhancements tab isn`t enough, the APO`s may still be present.
It`s good practice as well to avoid the upsampler, though I`ve achieved very good results in recent tests, much better than archimago`s results.
Once these steps are taken, Windows audio is faultless. It then allows EAPO to be used which provides significant audible benefits (faultless room EQ or headphone EQ) that far exceed benefits of using ASIO or WASAPI exclusive. I also measured the distortion of EAPO and its non existent as long as the system isn`t clipped. Finally, I also checked EAPO`s cramping for high frequency digital filters, and while not perfect, REW`s PEQ filters predict EAPO`s behaviour dead on. As long as the PEQs are designed with REW, there is no issue.
Windows also supports remote desktop from android so I can use my tablet and remotely control all eq settings, playbacks, everything. Similar to Spotify Connect`s convenience, but working globally over local file playback or streaming.
My detailed investigation and measurements are attached, but summarizing:
1. Avoid Windows`CAudioLimiter by ensuring signal never exceeds -0.12 dBFS. This requires:
a. Adding ~ 4 dB digital loss (pre-amp APO) if upsampling, to avoid intersample overs (see Benchmark site for detailed description)
b. If not oversampling, adding loss (I use 4 dB) if high pass filtering which can cause the maximum digital word to exceed the unfiltered maximum value
c. otherwise add at least 0.2 dB pre-amp APO loss even if not filtering or upsampling
2. Checking your system for `hidden`APO`s that can create distortion, and then disabling them (eg, using EAPO). My Dell tower had an APO that I believe to be related to the stock realtek card that caused terrible distortion similar to the OP`s, until it was disabled. `Disable all sound effects`in the enhancements tab isn`t enough, the APO`s may still be present.
It`s good practice as well to avoid the upsampler, though I`ve achieved very good results in recent tests, much better than archimago`s results.
Once these steps are taken, Windows audio is faultless. It then allows EAPO to be used which provides significant audible benefits (faultless room EQ or headphone EQ) that far exceed benefits of using ASIO or WASAPI exclusive. I also measured the distortion of EAPO and its non existent as long as the system isn`t clipped. Finally, I also checked EAPO`s cramping for high frequency digital filters, and while not perfect, REW`s PEQ filters predict EAPO`s behaviour dead on. As long as the PEQs are designed with REW, there is no issue.
Windows also supports remote desktop from android so I can use my tablet and remotely control all eq settings, playbacks, everything. Similar to Spotify Connect`s convenience, but working globally over local file playback or streaming.
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I've found DDF's same results but I'm scratching my head as to why the built in limiter is causing this distortion if it simply reduces gain. I would love to be able deactivate the limiter (and/or this crude clipper) so that I can get FS audio through my system.
I've asked this question on the Microsoft Community but no one has answered at all.
Windows 10 will not play a full scale digital signal without - Microsoft Community
I've asked this question on the Microsoft Community but no one has answered at all.
Windows 10 will not play a full scale digital signal without - Microsoft Community
in order to maintain the original waveform it would have to atenuate the whole amplitude, I think. A limiter will produce harmonics
A very interesting topic. I probably wouldn't even pay attention. As Sangram writes: professionals use ASIO. Greetings.
it seams it acts at -0.14dBFS. normaly there should be no signal reaching this. but yes, nowadays it happens all the time. now it will be a few fast transients. probably some of the snare hits most of the time. now they wont stop at 0dBFS, so it is better to limit them. I actualy doubt you will hear a diference with either with most material. it's just a a few ms transient.
now if you have some stupidly clipped source, it is easy to verify that you better have the windows limiter https://www.audiosciencereview.com/...ftware-volume-control.5922/page-2#post-172865
now if you have some stupidly clipped source, it is easy to verify that you better have the windows limiter https://www.audiosciencereview.com/...ftware-volume-control.5922/page-2#post-172865
Interesting work. The digital to digital results surprise me because years ago I was able to easily obtain bit perfect audio with windows XP. Going USB-SPDIF-USB between computers the audio was bit perfect to the original file. That was using music and test signals. I wonder now if my signals were full scale. 
Use your phone. Ios and android have lower latency vs windows but that is rather minor.
The fact the phone runs on battery and has tighter power noise tolerances yield 115db s/n and 0.005% distortion from iPhone 6 galaxy s10 is similar.
The fact the phone runs on battery and has tighter power noise tolerances yield 115db s/n and 0.005% distortion from iPhone 6 galaxy s10 is similar.
Technically WASAPI exclusive is more advanced than ASIO (multiple devices possible, no duplex requirement, more than two periods (buffers in ASIO parlance) to avoid buffer failures, access to control elements, etc.). But ASIO has been here for almost three decades, unlike the relatively new WASAPI, has taken over the (rather small) market as there was no alternative for long time, the inertia is huge.
Another point here is that ASIO has a license that makes it difficult to use in open-source projects. See for example Audacity and ASIO.
Hey Dave, How's it going? Its been a while since we all got together to chew the fat and listen to music.
When you mentioned EAPO did you mean Equalizer APO on sourceforge? When I search EAPO I get Elder Abuse Prevention Ontario. Considering my age it may be applicable. I also get a bunch of asian apps for windows and android.
Take care, stay safe.
johnk
When you mentioned EAPO did you mean Equalizer APO on sourceforge? When I search EAPO I get Elder Abuse Prevention Ontario. Considering my age it may be applicable. I also get a bunch of asian apps for windows and android.
Take care, stay safe.
johnk
Foobar allows WASAPI and ASIO with advanced control of buffers. WASAPI is easier to use. Both bypass the Windows audio issues. Its good to have options. Thanks to all the developers, its freeware.
Glad to hear it. I've been tempting to try a pi + Moode but Windows UI seems much easier and more flexible, and better supported by the streaming Apps.
I think a proper future for audio would be industry movement towards a turnkey as easy to use as Sonos or KT receiver dedicated fanless device that could do all this (room measure, eq+convolution, all the streaming apps + DLNA, same streaming UI flexibility and layout as windows) headless from a tablet or cell, but the future of audio is stuck in the past. There's always Roon or JRiver but they still keep you stuck on an OS that pushes updates