But it doesn’t matter. If an alien species whose hearing went up to 100 kHz came to Earth, they might be disappointed by the fidelity of CDs, but to humans, the sounds above 20 kHz are irrelevant.
What’s the beat frequency that results when you mix a 23 kHz sine wave with an 18 kHz sine wave?
It’s a perfectly audible 5 kHz wave.
Atually, it’s like 2.01. With a 44.1 kHz sample rate, you could perfectly reproduce a sine wave at 22.04 kHz. Filtering this would be a bear, but hey, you said “theoretically.”
I’ll grant you that much. However, this fact doesn’t relate to anything in the hifi world.
By that logic, if you play a 40,000 Hz tone and a 40,060 Hz tone at the same time, you should be able to hear a familiar 60 Hz hum, right? I don’t think it works that way.
A bit of searching has turned up explanations like this for why inaudible frequencies don’t produce audible beats (though apparently, it sometimes happens at very loud volumes that aren’t likely to be part of a musical experience.) If you have a cite saying they do, I’d like to see it.
In any case, if this effect were real, it seems like one could easily compensate for it by artificially inserting the audible beat frequencies before pressing the CD.
So, do you know how well the impedances are matched between the stages of your amplifier and other equipment? Incorrect driving and loading impedances distort the signal, in effect acting like filters.
If the impedances are not properly matched, then there is no telling what things will sound like.
Do you know how well your equipment is matched? Do you know what impedance is? Do you know how to read the output of an audio spectrum analyzer? Would you know what to do if the impedances on your equipment don’t match?
Christ. It is NOT philosophy. It is too many people who haven’t a clue as to what they are talking about. Bitching and moaning about jitter and sampling rates and quantization and how bad CDs are, but they have no concept of the problems that exist in the purely analog realm.
Get a clue. Get a grip. Learn about electronics and acoustics and come back and we’ll talk about it.
Yes, and that 5KHz component will be represented in the recording on the CD. The mixing takes place at the micrphone as well as at your ear.
In any case, it is irrelevant. If a CD can’t reproduce it, neither can your vinyl. Vinyl has even less bandwidth than the CD.
Those of you who insist that vinyl is less distorted should take a look at the work that goes into reproducing a signal from vinyl. If you knew anything about electronics, you’d see quite quickly that vinyl recordings are far more distorted and degraded by the processing they go through than everyone usually assumes.
That you might be acclimated to those distortions and like hearing them better than you do the technically less distorted CD is a different thing, and that probably does get into that philosophical realm that Crandolph mentioned.
Further to Crandolph’s comments re bad modern music:
Most recordings of modern music sound crappy because they are made by people with no clue (technically speaking) of performers with no talent playing music with no soul.
I have said it before, and I’ll say it again:
I’d rather hear a bad recording of good music than a good recording of bad music.
Blaming the technology for the dismal quality of commercial music offerings is just shooting the messenger.
100% perfect reproduction of shit is still shit.
Well EXCUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUSE me! I am obvously sick and wrong for having an opinion (shared by hundereds of thousands of vinyl collectors throughout the world) on how vinyl sounds. I am the 98 pound weakling of the Popular Mechanics He-Man Woman-Haters Treehouse Club and sand should; nay, sand must be kicked in my face! :eek:
Clearly when Dave Davies took a razor blade to his speaker cone in 1964 to produce all that distortion on records that were produced in mono to be played upon dinky turntables and transitor radios, it was so that I would, some 40 years later, read the input of my audio spectrum analyzer and match the impedance of my equipment in order to realize, for the first time, the FULL ARTISTIC VISION of “You Really Got Me.”
Indeed.
Is there any research on 'roid-rage like symptoms from spending too much time near an audio spectrum analyzer? 
This site suggests pretty strongly that modern production of new releases and remixing of older releases has been getting progressively worse (the webmaster seems to have a beef primarily with overcompression) on new CD releases.
This suggests very strongly to me that old copies of vinyl may be your best bet to hear older music as it was intended to be heard by musicians and producers at the time it was recorded.
Assuming that you have vinyl that was properly mastered, manufactured, stored and never played. Quality control on vinyl was poor, especially after oil prices went up and many manufacturers went on cost-cutting binges. Stampers were not replaced until they were completely shot. Vinyl was adulterated with cheap and noisy fillers. The amount of vinyl was reduced, resulting in warp-prone records. Dynamic range was poor and the high frequency content had a short life-span when played on anything less than a carefully maintained “audiophile” turntable, arm and cartridge.
No, but I work in electromagnetics, and do a lot of data processing using similar math. I once wrote a code to resample CD audio to speed up or slow down the audio by small amounts, and ran into some of these issues (especially, how hard it was to properly interpolate the higher frequencies of CD audio). I got a couple of the papers you mentioned. Thanks for the pointers.
ouryL wrote:
You can’t really compare records and CDs directly, unless you can be certain they are using the same master. I’ve been transfering my vinyl records to CDs, and was recently recording “Blind Faith”. I also have Eric Clapton’s Boxed set from around 1988, also on vinyl, which has a couple of the same songs. I thought I’d listen to both, decide which one had less noise, and keep that copy, but it turned out there was a huge difference in the sound. The boxed set version was <insert every flowery audiphile adjective they use to describe the effect of some overpriced or useless gizmo you can think of here>. Seriously. It turns out the recordings on the boxed set were digitally remastered. I think you’re right that the earliest CDs were crappily made, but there’s no telling how much extra processing is being done with new reissues.
Personally, I’d rather transfer a vinyl record to CD myself, than have a CD that was overcompressed. But that’s not a problem with the medium.