Frequenc Spectrum of CDs vs. LPs (1 Viewer)

[Mat_M]

I thought I'd pass this along...

Today I went to a local "hifi" dealer here in Tempe, Arizona. I spoke on and off with the owner in between my listening sessions of the setups in the store. After a while a gentleman walks into the store and starts talking to the owner about the frequency spectrums of CDs and LPs. The owner then proceeds to tell him that LPs have a 'far superior' frequency spectrum than CDs. "Up to 88kHz," he says.

Now, my gut instinct was, "what the bloody hell is he thinking?!?" I know that the Nyquist theorem limits a CD to 22kHz (44.1kHz sampling rate).

Well, an LP is an analog source...So how can I tell what the frequency spectrum is? I've looked online, in books, here, and there is nothing I can find to justify his claim. I'm VERY skeptical of this claim, and was wondering if anyone knows of any credible sources to back him up?

What gives???

 

[Brian Bergen]

According to a textbook i have Audio in Media by Stanley R Alten, isbn 0534196020. the frequecy response for an lp is 40hz to 10,240hz. A cd has a frequency response of 20 hz to 16,000 hz.

I am not sure if I am answering your question though.

 

[Wayne A. Pflughaupt]

No way he can know that first hand - his dog must have told him.

Regards,
Wayne A. Pflughaupt

 

[Mark All]

A good phono cartridge for LP playback does have a wider bandwidth than CD, but less than the theoretical limits of SACD or DVD-A. Check out some of the specs on phono cartridges and you'll find most in the range of 5hz to 32kHz, with more expensive ones going even higher, possibly up to 88kHz. The specs don't mean a lot though because phono pre-amps usually limit the usable audio spectrum on LPs from 20hz to 20kHz. One of the problems according to audiophiles with CDs is that filters sharply cut off frequencies above 20kHz resulting in a certain harshness to the sound. This is why audiophiles will say they prefer the sound of LPs over CD. SACD and DVD-A are touted as superior to CDs in part because they have frequency ranges that do not cut off sharply.

 

[David Judah]

Then the media is the limiting factor, despite the higher limits of the cartridge and the phono preamp, it sounds like.

DJ

 

[Mark All]

I'm not sure how old Stanley Alten's textbook is, but the frequency response limits for vinyl haven't been at those levels since the 1950s. Most people didn't have speakers capable of reproducing sounds beyond those levels so there was no need to put full frequency recordings on vinyl. Vinyl as a medium has a higher potential limit for high frequency reproduction than CD because there's no built in brick wall frequency response limit for vinyl. Whatever frequencies are put on vinyl can be played back. Put on a copy of the Cardas Frequency Sweep LP and look for Track 2a which goes from 30Hz to 30kHz. People won't be able to hear the limits of the frequency sweep, but a turntable can reproduce the sounds.

 

[David Judah]

Thanks for the clarification, Mark, but what about wow and flutter & dynamic range? .

DJ

 

[Mat_M]

So from the looks of it, there's only one credible source so far, and that claim is only to 10.24kHz. For those of you giving the better specs on the lps, what are your sources?

As for Cardas, if it's the same George Cardas who makes $3 cables and sells them for $1000, I won't even consider that garbage.

 

[Mattias_ka]

Mat_M, Your wrong.
First, in the 70's there was 4-channel LP's where the 2 "surround" channels was in the 30-40KHz range on the vinyl.
Second, according to Kevin Grey (that cut vinyl's daily) his cutting system; With frequency response from 7 Hz to 25kHz (I think his laters measuring was at 27KHz. Taken from: http://www.recordtech.com/prodsounds.htm


David Judah, Well, according to Kevin Grey again, vinyl has; over 75 dB dynamic range possible.
The reason he say over is because you can with good gear "hear thru the noise floor".

 

[Wayne A. Pflughaupt]

Possible perhaps, but not common. Acording to information I saw published in Stereo Review back in the day, the S/N ratio of most commercially-sold records was less than what you would get with a Dolby B cassette (which is typically about 65dB).

Regards,
Wayne A. Pflughaupt

 

[Mat_M]

7Hz to 25kHz is FAR from 88kHz; and I have seen NOTHING that states the medium can go to 40kHz.

 

[Mattias_ka]

Well, we are talking about what CAN be stored on a vinyl LP. What mostly are are not intresting. Most CD's now have at most 10 maybe 15 dB dynamic range so have CD's only a 15dB dynamic range? No off course not.

 

[Wayne A. Pflughaupt]

Absolutely not so. You're talking the about the dynamic range of the recording. Yes, recordings are overly compressed and exhibit limited dyamics. That's not the same thing as the dynamic range of the medium, which includes any inherent noise present during the quietest passages i.e., between songs.

If CDs truly only had a 15dB dymanic range, you would hear audible hiss between songs.

 

[Mark All]

I'd tend to agree with Wayne in that the store owner's original comment was a generalized statement, a generalized overstatement even, but understandable given that he knows and sells hardware. Expensive moving coil cartridges are easily capable of reproducing frequencies in excess of 80kHz at a -3db limit. Look for any high end cartridge from companies like Ortofon and the frequency response ranges will be apparent. On the lower end of the sound spectrum, vinyl related hardware is not able to get to the 2Hz limits of CD technology.

From the perspective of the actual vinyl medium and disk mastering, the owner's statement can be taken as incorrect. Vinyl does have limits as a medium that hardware exceeds by a considerable margin. In practical usage, recordings on vinyl won't normally have information below 40Hz, but there is no set bottom limit. Low frequencies take up a lot of space on an LP, but it is possible to put pipe organ music on an LP and the frequency sweep mastered by Stan Ricker on the Cardas Sweep test LP does go to 30Hz. As a medium though, I'd say that CD is better in its potential to contain low frequency tracks. On the other end, LPs won't have frequencies much above 30kHz because normal vinyl available in the U.S. isn't hard enough to allow recordings to be usable for multiple playbacks. There are a number of other problems associated with putting ultrasonic information on an LP, but it can be done. There is no need to put ultrasonic information above a certin level on an LP though because, after all, no one can hear much above 20kHz. The important thing to remember about the upper frequency range of LPs is that they do not have to cut off everything right at 20kHz. The inclusion of a certain amount of ultrasonic information on LPs (and now SACD and DVD-A incidentally) pleases the golden eared audiophile crowd. This was most likely what the store owner was referring to. So, although certainly not an idiot, he was being a salesman.

 

[Mattias_ka]

Wayne A. Pflughaupt, Well, there are vinyl with over 22KHz so it's right like I said.




Wordfarting. What you get when you buy a LP or a CD is the combined result of:
*Recording
*mixning
*mastering
*format

And when most CD's have MUSIC that have only 10-15 db dynamic than it's rather uninteresting to talk about the 96 db dynamic range that never are used.

 

[Chu Gai]

I'll just bet there was a bit more commision in that vinyl wouldn't you think? Mattias, you've got to stop listening to Britney Spears. Turn the sound off and just look. It's healthier!

 

[Wayne A. Pflughaupt]

Let me make sure I have this straight, Mattias: We're talking about what CAN be stored on vinyl, but we're not talking about what CAN be stored on CD? Hmmm...

 

[RobertR]

But that's not the same as saying that they were capable of linear, high level playback at those frequencies. It was simply a subcarrier signal.

The quoted claim of 88 kHz for vinyl doesn't really hold up, considering the practical difficulties in putting a musical frequency that high on a record. I seriously doubt that anyone can show me more than a tiny handful of LPs that have significant output above 15 kHz on a spectrum analyzer.

 

[Mat_M]

Yep....exactly

 

[Mattias_ka]

Well Robert, you are already biased so there is no meaning to show you otherwise. But I hope you only buy PAL DVD's because they are sooo much better than NTSC DVD's.