I wonder how a CD sounds with a cat's hearing?
I have noticed that the sound volume when my cats prefer to leave the room is much louder for vinyls than for CDs. I'm aware that this is not a scientific proof, that the statistics are insufficient, if not non-existing, that the effect could have other causes such as simply sharper transients on CDs than on vinyls and all that - But bear with my little thesis and observation. Cats are supposedly able to hear frequencies up to about 48 kHz so the sampling frequency of CDs must have some audible tone, timbre, distortion or other effect on my furry friends' perception of CD sound.
Does anyone here share the same experience?
Just a thought: Would it be possible to sample a piece of music with for instance half the normal sampling rate and get a feel for the effect myself with my own ears? By 'possible' I mean: Is it something that can be easily done with a normal sound card in my PC and/or Audacity? (I never noticed an option to choose a sampling frequency in the audible range: As far as I recall the choice is between 22, 24, 48 and 96 kHz. And 80% of all the functions in Audacity leaves me clueless as to what they are and do
). Perhaps somebody knows an off-hand trick to do this.
(Hope the Lounge is an appropriate forum for this post, or that a moderator will guide it to a better place).
I have noticed that the sound volume when my cats prefer to leave the room is much louder for vinyls than for CDs. I'm aware that this is not a scientific proof, that the statistics are insufficient, if not non-existing, that the effect could have other causes such as simply sharper transients on CDs than on vinyls and all that - But bear with my little thesis and observation. Cats are supposedly able to hear frequencies up to about 48 kHz so the sampling frequency of CDs must have some audible tone, timbre, distortion or other effect on my furry friends' perception of CD sound.
Does anyone here share the same experience?
Just a thought: Would it be possible to sample a piece of music with for instance half the normal sampling rate and get a feel for the effect myself with my own ears? By 'possible' I mean: Is it something that can be easily done with a normal sound card in my PC and/or Audacity? (I never noticed an option to choose a sampling frequency in the audible range: As far as I recall the choice is between 22, 24, 48 and 96 kHz. And 80% of all the functions in Audacity leaves me clueless as to what they are and do
). Perhaps somebody knows an off-hand trick to do this. (Hope the Lounge is an appropriate forum for this post, or that a moderator will guide it to a better place).
I have no idea. I have been playing CDs for a while on a cheap Denver DVD-player.
Maybe this answers your question?
Yesterday I finally got enough of it and bought a Denon CD-player (for reasons that has more to do with convenience and ease-of-use than sound - the DVD-player has no display to tell you wich track is playing, no cutout on the sides of the drawer so you can grab the CD by the edges and was really sluggish to change tracks, start/stop a.s.o.). So far I haven't noticed any difference in the sound between the two players, but I haven't really compared them either. I'll try to notice if the too-loud-for-cats threshold has changed now...
Well,
I have two examples.. unfortunately not cats though..
Some years ago when I was using meridian cd player and linn LP12..the dog would go behind the sofa with the CD on, when playing a record he would sit by the tube amp and go to sleep..
The same would happen with my son at the time a baby..he would go to sleep with record playing but not with CD..and its interesting because it would happen with heavy rock..or soul music..or R&B..
Regards
M. Gregg
I have two examples.. unfortunately not cats though..
Some years ago when I was using meridian cd player and linn LP12..the dog would go behind the sofa with the CD on, when playing a record he would sit by the tube amp and go to sleep..
The same would happen with my son at the time a baby..he would go to sleep with record playing but not with CD..and its interesting because it would happen with heavy rock..or soul music..or R&B..
Regards
M. Gregg
Cats, dogs and babies all (normally) have hearings that go beyond 20 kHz. So I would call this a valid observation.
Fortunately, I'm no longer cursed with the ability to hear much over 14 Khz. It has been some years since I was unable not to notice a CRT-TV by its line-shift ringing even several rooms away, if the doors vere left open. That is 15.625 kHz in Europe AFAIK. As a child, up to my late teens, that tone really annoyed me. Turning up the volume on the TV usually helped drowning it. But I remember some TVs vere so badly constructed that the audio circuits were also infected with that constantly ringing tone and just amplified it
A conventional DAC should not output anything above 22kHz, but a NOS DAC could go well beyond that with image frequencies. A DVD player is most unlikely to use NOS. A cheap DVD player might have poor filtering so lots of HF mush. Bitstream?
On the other hand, LP can sometimes go quite high in frequency, depending on cartridge and preamp. The shape of the spectrum might be different: LP gradually sloping off at HF, CD having a cliff-edge between 20kHz and 22kHz.
Maybe all listening panels should include a few cats?
On the other hand, LP can sometimes go quite high in frequency, depending on cartridge and preamp. The shape of the spectrum might be different: LP gradually sloping off at HF, CD having a cliff-edge between 20kHz and 22kHz.
Maybe all listening panels should include a few cats?
Back when I worked as a repair tech in a stereo store (1971-1972) JVC invented and licensed to the world a new vinyl format for putting 4 discrete channels on a vinyl record. This was called CD-4 for Compatible Discrete - 4 channel). The CD we know today wasn't even a dream yet.
This required new hardened vinyl, new cartridges, new eliptical "Shibata" stylus, and new record pressing equipment. It worked by using a subcarrier at 30 KHz with modulation info reaching to 45 KHz. A special CD-4 demodulator was inserted in place of the phono stage which had 4 outputs. A few receivers were marketed with the CD-4 decoder built in.
The CD-4 format failed in the marketplace for many reasons including the declining interest in quadraphonic sound. There were also several technical issues that were never fully worked out.
The records that fully complied with the new vinyl and pressing methods spelled out by JVC were called "Quadradisc". These supported 45 KHz information. There were some inferior product on the market, and it was discovered that repeated playing of a Quadradisc with a conventional conical stylus would damage the high frequency information in the grooves rendering the record unplayable, or highly distorted on a CD-4 machine. A list of compatible equipment was supplied, but not always up to date (no internet in 1972, infact no computers) and some compatible equipment....wasn't.
The advances in vinyl production needed for CD-4 were applied to many record pressing plants, making some records better overall.
A CD-4 record has a 30KHz tone recorded on both channels. I still have at least one (Doobie Brothers) CD-4 record, and the tone can be seen with a scope probe on the turntable output cable (it won't make it through the RIAA filter of a phono stage). You can also hear a sweeping tone if you turn off the turntable while the record in playing so that it slows down bringing the 30 KHz tone down into the audio range.
This format proved that vinyl could handle at least 45 KHz on some equipment, in 1972.
Note:
Some CD players exhibit aliasing issues which are audible to humans. The effects are often masked when playing music, but are plainly audible with a test tone CD. If you have (or make) a CD with discrete tones recorded at a single audio frequenciy you should hear only that tone when the disc is played back. Some CD players will also produce an alias tone at 22.05 KHz - the tone frequency. So playing a 15 KHz tone will also create a 7.05 KHz tone at a lower level. This can create ambiguous high frequency information that a human may not hear, but contributes to listener fatigue.
Still I have a cuple of them from my father's collection. They ar called "Cuadraphonic", and there was a Motorola IC to decode them.
This ought to be almost impossible. It would require significant non-linearity in the analogue stuff after the DAC, or a mistake in the code for the digital filters. I suppose sending sharp-edged pulses from the DAC straight into an inappropriate opamp might push it into non-linearity. In either case the effect of the non-linearity would be to produce IM between the signal (below 22.05kHz) and the HF images (above 22.05kHz).tubelab.com said:
The same effect could happen in a line stage or power amp fed from a filter-less NOS DAC.
On a modern oversampling player with a digital filter it is. Older machines ran a 44.1KHz converter with an analog filter and aliasing was possible and audible. I had a old Sharp CD player that sounded bad and I never knew why. I got a test CD for use as a signal generator for testing amps and it became obvious. It had a collection of tones at discrete frequencies. There are tones every 1KHz above about 5 K. Aliasing was audible for every tone above about 12KHz. The Sharp went into the trash.
I have heard some funny stuff on some car CD players but it couldn't be called aliasing since there weren't discrete tones being generated.
That is a different format. When Quadraphonic sound appeared in about 1970 there were several non compatible formats. I had a quadraphonic 8 track player in my car. It used the Q8 format that had 4 discrete tape tracks. There was a 4 channel reel to reel format, and at least 3 different formats for vinyl offering varying degrees of compatibility. The previously described CD-4 system allowed 4 discrete tracks on vinyl but wasn't compatible with any other 4 channel format.
There were several "matrix" systems that created a 4 channel image via addition and subtraction of one channel from another. There were channel seperation issues with each format, but relative compatibility among all of them. Sony created the SQ system, there was a QS system and Sansuii created the QS vario-matrix system. Motorola created a chip that could decode all of the matrix formats. this chip was used in many decoders and receivers.
A record labled Quadraphonic is recorded using one of the matrix systems using conventional equipment. A small signal processor was used during the mixing process to creat the master. The QS system was the most popular in the US. Quadradisc was a registered trademark and only applied to CD-4 records. They were never very common due to the issues with reliable playback. They did sound awesome when everything worked though.
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