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Frequency response while streaming stops at 15kHz- did I miss something in the fine print?

I am streaming with Qobuz.  It sounds great playing both CD quality and hi-rez music.  So what's the trouble?  While working to get the bass response in my room just right I found test tracks on Qobuz.  This was very handy as I played 30-60 Hz test tones over and over.  So when I was done with that I streamed a pink noise track and pulled up the FFT analyzer app on my iPhone.  Surprisingly, I see the trace drop straight down to 0 dB above 15 kHz.  I streamed some test tones and confirmed that above 15 kHz nothing is happening at the speakers.  In my old and decrepit state I can no longer hear above 15 kHz so I am relying on the app.  In a panic that something is wrong with my speakers I pull out my vinyl test record.  I have a nice, pretty flat frequency response from 20-20 kHz showing on the FFT app.  I put in a test CD and again show a good 20-20k.  Lastly, I ripped the test CD onto my server and again had a good 20-20k response.  So why did I not know about the limited bandwidth while streaming?  Is it just me?  It is an abrupt cutoff above 15 kHz while streaming.  What's going on?
128x128tonywinga

Showing 2 responses by audiom3

audiom3
138 posts
 
Which vinyl test record do you own that's flat out to 20kHz?  I have yet to find one.  I have three and all drop fairly sharply at around the 16-18kHz range.

Also, I preferred the sound of Tidal when I compared it to Qobuz earlier this year.  Tidal had more treble extension to my ears and Qobuz had more bass and midrange warmth.  We are talking about the margin of splitting hairs here though. 
I don't doubt you are reading a 15kHz cutoff but I am pretty positive I am hearing over 15kHz with Roon/Tidal in my setup.  Are you sure your streamed audio isn't being transcoded somewhere in your audio chain?  Not sure what frequency response mp3 has because I never listen to them.
audiom3
138 posts
 
@tonywinga I’m not sure what’s going on then. I pulled out a spectrometer app just for kicks and I get plenty of action even over 20kHz+ (at my listening position) with Roon+Tidal in my setup. All fiber LAN. Running a mini PC feeding a PS Audio DS DAC Bridge II to Ayre KX/VX-5 Twenty pre and power amps powering Legacy Focus SE speakers. /shrug, all good here.
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