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#1
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[OT] Odd speed fluctuation when streaming to car
Android phone plays Spotify over bluetooth into car stereo.
Particularly soon after starting play, I get what sounds like speed changes as though someone has their finger on an LP. After a while it smooths out. I'm getting maybe a couple of hundred cents variation, just as a guess. I was curious as to who was responsible. I haven't tested with another device but I suspect the 2017 Hyundai. |
#2
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[OT] Odd speed fluctuation when streaming to car
Tobiah wrote: "Android phone plays Spotify over bluetooth into car stereo.
Particularly soon after starting play, I get what sounds like speed changes as though someone has their finger on an LP. After a while it smooths out. I'm getting maybe a couple of hundred cents variation, just as a guess. I was curious as to who was responsible. I haven't tested with another device but I suspect the 2017 Hyundai. " You're just imagining things. PSYCH - Just kidding! I noticed that also, via the Blue Tooth in a 2013 Sonata LTD I drove some years ago. The first 30 or sec. the speed was just a tad too high - like a 33 1/3 record at 34rpm - then returned to normal. This from the company that totally fubared their first US models with electric power steering: things were all over the road!! Don't count on much help here with it, though. |
#3
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[OT] Odd speed fluctuation when streaming to car
I'm getting maybe a couple of hundred cents variation, just as a guess. I meant a fraction of a half-step, like 10 or 20 cents. |
#4
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[OT] Odd speed fluctuation when streaming to car
Don't count on much help here with it, though.
No help required; id est, quid id est. I just thought it might create some interesting discussion as this group gasps its last. |
#5
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[OT] Odd speed fluctuation when streaming to car
Tobiah wrote: "id est, quid id est. "
PUSSY statement! NOTHING of human creation or decree "is what it is". If humans made/did it, it can be changed/fixed/ eradicated, whatever. Nothing personal, I just think it's a signal of resignation when someone says that. I did bring up this temporary Bluetooth speed playback issue on an automotive forum, and all it got were crickets - even two years hence, and I no longer drive that car. |
#6
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[OT] Odd speed fluctuation when streaming to car
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#7
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[OT] Odd speed fluctuation when streaming to car
John Williamson wrote: "
The correct solution is to apply test equipment to find out where the variation in clock speed on playback is occurring, and fix that. The problem is unlikely to be caused by the bluetooth connection, unless the bluetooth clock is locked to the playback clock, which on cheap gear can happen if they use the same crystal for timing both. -- Tciao for Now! John. " The problem is, we both heard this speed up via the Blue Tooth in these Hyundais. And it lasted under one minute, for me anyway. I never experienced it with any other Blue Tooth scenario, IE, a BT speaker in a store. And via hardwire - playback speed was always correct, in the cars, and anywhere else. So what else could explain it? |
#8
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[OT] Odd speed fluctuation when streaming to car
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#9
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[OT] Odd speed fluctuation when streaming to car
Theckhhhmaaash gibberered:
I did bring up this temporary Bluetooth speed playback issue on an automotive forum, and all it got were crickets - even two years hence Your vapid gibbering was ignored, and two years later, you're still butt-hurt and whining about it. Thats ****ing retarded, li'l buddy. HTH. LKINHSF. |
#10
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[OT] Odd speed fluctuation when streaming to car
"John Williamson" wrote in message ...
By the way, your newsreader seems to be broken, hiding your response after the sig seperator. It may be dumb **** operator error. |
#11
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[OT] Odd speed fluctuation when streaming to car
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#12
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[OT] Odd speed fluctuation when streaming to car
John Williamson wrote: "That is what the test equipment is for. No need to speculate, it will
tell you. " Two people on this thread experienced the same speedup of playback via Blue Tooth, in the same make of car with the Blue Tooth feature. They experienced it nowhere else. Nobody is speculating. Are you suggesting we are both lying about our experiences? |
#13
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[OT] Odd speed fluctuation when streaming to car
John Williamson wrote:
On 13/07/2018 00:33, wrote: I did bring up this temporary Bluetooth speed playback issue on an automotive forum, and all it got were crickets - even two years hence, and I no longer drive that car. The correct solution is to apply test equipment to find out where the variation in clock speed on playback is occurring, and fix that. The problem is unlikely to be caused by the bluetooth connection, unless the bluetooth clock is locked to the playback clock, which on cheap gear can happen if they use the same crystal for timing both. The Bluetooth clock and playback clock very nearly have to be completely independent. -- Les Cargill |
#14
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[OT] Odd speed fluctuation when streaming to car
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#15
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[OT] Odd speed fluctuation when streaming to car
theckmah @ dumb****.shortbus.edu gibbered:
Nobody is speculating. You are speculating. Are you suggesting we are both lying about our experiences? Nobody's suggesting that you're lying. You're just a retarded idiot whining about something you're too stupid to comprehend. Short-bus dumb ****. HADH. SJF. FCKWAFA! |
#16
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[OT] Odd speed fluctuation when streaming to car
there is some interesting technical data here
https://www.eetimes.com/document.asp?doc_id=1277103 I wonder if the system was not well designed for VBR MP3 files. Can you try to compare the results using VBR vs CBR MP3 files? mark |
#17
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[OT] Odd speed fluctuation when streaming to car
mako wrote: "I wonder if the system was not well designed for VBR MP3 files.
Can you try to compare the results using VBR vs CBR MP3 files? " Great suggestion! If Tobiah still owns his car with BT enabled stereo he should try that. I noticed that too, when playing CDs with mp3 files on a CD player that can play those disks, occasionally it has a hard time with VBR files. Remember, CD players are looking for a sampling rate to control their inner clock so the disc plays back at the correct speed - without stuttering or pitch/tempo changes/Mickey Mouse effect, etc. We all know that value - 44.1kHz. That's precisely 44,100 Hertz, not 44,099 or 44,100.3. Sometimes, even on a newer CD player that can play back mp3s off a disc, something other than desired, is heard. ! |
#18
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[OT] Odd speed fluctuation when streaming to car
Thechhhmaaaah ( tardsRtheckmah @ dum****.shortbus.edu ) kook-gibbered:
We all know that value - 44.1kHz. That's precisely 44,100 Hertz, not 44,099 or 44,100.3. A sample rate of 44100.3 hertz is within specs for most consumer-grade CD players. Numbers are never your friend, li'l buddy, especially when you're just pulling them out of your bung-hole to pretend that you understand. SBDF. |
#19
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[OT] Odd speed fluctuation when streaming to car
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#20
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[OT] Odd speed fluctuation when streaming to car
On Tuesday, July 17, 2018 at 10:31:41 AM UTC-4, wrote:
mako wrote: "I wonder if the system was not well designed for VBR MP3 files. Can you try to compare the results using VBR vs CBR MP3 files? " Great suggestion! If Tobiah still owns his car with BT enabled stereo he should try that. I noticed that too, when playing CDs with mp3 files on a CD player that can play those disks, occasionally it has a hard time with VBR files. Remember, CD players are looking for a sampling rate to control their inner clock so the disc plays back at the correct speed - without stuttering or pitch/tempo changes/Mickey Mouse effect, etc. We all know that value - 44.1kHz. That's precisely 44,100 Hertz, not 44,099 or 44,100.3. Sometimes, even on a newer CD player that can play back mp3s off a disc, something other than desired, is heard. ! VBR and CBR refer to the MP3 data bit rate. The audio sample rate is always (supposed to be anyway) constant. m |
#21
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[OT] Odd speed fluctuation when streaming to car
mako wrote: "VBR and CBR refer to the MP3 data bit rate."
I, and my cats, all know that. "The audio sample rate is always (supposed to be anyway) constant. m " Perhaps the machine playing discs with VBR mp3 is confusing which ahould be constant and which is variable. |
#22
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[OT] Odd speed fluctuation when streaming to car
On 18/07/2018 14:11, wrote:
" Perhaps the machine playing discs with VBR mp3 is confusing which ahould be constant and which is variable. if the machine playing back the mp3 gets confused, it just rejects the file. Playing back a VBR file using the CBR algorithm or vice versa just outputs garbage, not a change in speed. There is some info on the file structure he- https://en.wikipedia.org/wiki/MP3#File_structure MP3 files consist of "frames" which have information encoded in them to reconstruct (more or less) a section of the original waveform. The frames are all timecoded, and the player outputs the reconstruction of the encoded waveform held in the data blocks using a fixed clock rate specified in the file header. In fact, read the whole article, and you will know a lot more than you want to know about mp3 playback and encoding. -- Tciao for Now! John. |
#23
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[OT] Odd speed fluctuation when streaming to car
John Williamson:
This is what happened one time when playing VBR MP3 on a compatible player: "I Pledge Alleg - the flag of the Unit - tes of America, and - public for which it stands, one - under God, Indivisible with lib - ustice, for all" Like it was skipping chunks. So I re-encoded to CBR, problem solved! |
#25
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[OT] Odd speed fluctuation when streaming to car
On 22/07/2018 03:50, Jason wrote:
In article , says... If you ever find a CD drive raw output that feeds the electronics a constant sample rate of 44,100Hz, I'll probably faint with shock. Just a guess.. could the variation be caused by error correction occurring? The errors might be on the disc or induced by less-than-superb mechanics in the player. Reading CDs is an analogue, mechanical process. The disc does not spin at a uniform rate, but changes speed as it is read, both deliberately and due to feedback and mechanical errors in the control circuitry and motor. While the output of the phase detector is supposed to be either on or off, dirt on the disc or using dye based writeable discs causes it to vary, so threshold comparison is the order of the day. The error correction introduces a delay in the chain from laser to DAC input. This is why the electronics has a buffer, so that the DAC and error correction circuitry can be fed clean digits at a known clock rate and output a clean signal at the right speed. -- Tciao for Now! John. |
#26
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[OT] Odd speed fluctuation when streaming to car
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#27
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[OT] Odd speed fluctuation when streaming to car
Jason wrote:
In article , says... The error correction introduces a delay in the chain from laser to DAC input. This is why the electronics has a buffer, That would prevent what I guessed might be the problem... Also, note that MP3 files at any bit rate take up less space than the equivalent WAV file (which is kinda the whole point of the exercise), so the requirement for data rate out of the transport is lower than the design spec. No transport mechanism should break a sweat playing back an MP3 file or have any difficulty keeping the playback buffers full. |
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