Axiom Home Page Forums General Discussion Technical Questions cd mods...Music Hall MMF-CD25

I promise on my family's graves three generations back that the supplied files are exactly as I have suggested (within the limits of integer math - for instance if a sample of noise is at 5/65536 of full scale and you half it, it'll be rounded up to 3/65536 since digital samples are never expressed in floating point math) but obvious caveats aside, this is a more than fair assessment of all these numbers and discrepancies everyone throws around but hardly anyone understands.

Bren R.

That's excellent Bren.
I can't hear much of anything on my computer system, but then again even with decent speakers the hum of my computer, trucks outside the window and such really don't help the critical listening process. However, i will be burning a new reference disc at some point so i will run these through my Axiom basement setup and see what comes of it.
If you have anything else to throw together like that for a 'test' disc, i would certainly love a copy.

Wow - that's excellent!

Nope, I can't take the trophy.

But some comments anyway - 3db is not twice as loud - it's "slightly louder" according to Axiom's own articles. 10db is twice as loud. Your point is still valid though - it's much greater than even an average HTIB.

6 jitters - each less than 23microseconds long. If there were simply six wrong notes that long, you wouldn't hear those either.

To put it in perspective (if ya don't wanna bother doing the math) there's room for 264,000 errors in that six second clip. Roughly.

This isn't to say you're aren't 100% correct in your test idea - it's a GREAT idea! I just think the sample isn't suitable for this type of test.

Try the intro of Beethoven's Pathetique. Or nearly anything off Johnny Cash's first American Recordings CD (can't recall the name of it...starts with Delia's Gone).

A blatant error by the guitar player would barely be noticable in your tracks - that music is busy!

One sample jitter is 23 microseconds of change. The noise floor, while HUGE by the standards of silence, is tiny compared to the busy tune. These things are heard during subtle quiet accurate clean nearly-naked pieces of music, especially during decays and rests.

I think your effort is fabulous - and although I didn't hear a difference, we all know there IS one (or two) now!

I'm just not convinced (yet) that I'd NEVER hear it, given the right piece of music, whatever that is.

I not really sure one "jitter" (the 23uS) is even audible - I think our limit of discrimination is more like 30uS. But I think my kmart cheapie on a bad day strings all six screw ups together, and THIS, you might hear.

Intersting notes BR.

My take on it:
You bring up a good point that i look at as an idea that goes towards the futility of trying to find audio perfection. Although some errors MAY be delineated on certain music passages, a person should ask, "how often does such a condition occur to warrant the requirement for an amazingly refined piece of equipment when even an overdone error [such as Bren has put forth] is incredibly hard to hear on a relatively simple music selection?"
To hear even a truly blatant error (and anything beyond HTIB spec has to be beyond blatant), one must be listening to a specific music piece, recorded with utmost precision (a massive caveat in its own right), and only during a quiet passage?
There is a strive for audio perfection and then there is going overboard. If anything, ppl should be striving for a demand in better quality recordings, not just for the boutique name music groups, but for all bands, even the Spears and boy bands of our time, rather than pursue the beyond human limits equipment that will do so little to the sound reproduction itself (too many previously mentioned limitations).

Audio is still about the hobby though and one's perception of the fun of it. I love to think my shiny new cdp is actually better than my old one in some respects. I certainly have a pride in ownership once i buy something. But the reality of the finite occurrences, under which i've described, that a person could potentially hear a slight difference in sound fidelity is so incredibly remote, is it worth the cost of some of the crazy "upgrades" people buy?
Some will say "yes", and some will say "no".
Personally, i'm in the no camp. I view it as a situation where one worries the spec of sand on the 10 mile beach is not as brown as all the others. First you have to spot it!

Kudos for the sound bits though. These types of tests are good fun to challenge ones ears. Hopefully the Axiom folk with have a good demo setup for the picnic. It looks like i will be attending at this point. Hmm, perhaps an addition to the picnic thread to see who will be going is in order.

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But some comments anyway - 3db is not twice as loud - it's "slightly louder" according to Axiom's own articles.

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Correct, a logarithmic scale, twice the power (watts) is a 3dB increase, 6dB is twice the signal, and 10dB is perceived as twice as loud. Was rushing through what started out as just a message and ended up as a theory lesson and made a mistake of logic.

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Try the intro of Beethoven's Pathetique. Or nearly anything off Johnny Cash's first American Recordings CD (can't recall the name of it...starts with Delia's Gone).

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PM me with a way to get a clip (uncompressed WAV/AIFF/etc) of it, and I'll do the same for it.

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One sample jitter is 23 microseconds of change. The noise floor, while HUGE by the standards of silence, is tiny compared to the busy tune. These things are heard during subtle quiet accurate clean nearly-naked pieces of music, especially during decays and rests.

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Again, my model took into consideration an insanely large amount of white noise - enough that it was clearly audible by itself. You'd definately hear that much during a rest. The actual amount of noise differential we'd be talking about between DACs would be a LOT lower, to the point where giving your ears a good cleaning before each listening would do much more for your enjoyment than the chip would.

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I not really sure one "jitter" (the 23uS) is even audible - I think our limit of discrimination is more like 30uS. But I think my kmart cheapie on a bad day strings all six screw ups together, and THIS, you might hear.

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Then the player should be thrown out. Even a CD-ROM that was packing it in on one of my computers could manage 1-3 jitter errors per track on average (while ripping at 4x). We're talking a CD-ROM that would take an extra 5-6 seconds to recognize a CD and bit the bullet about 2 weeks later.

Bren R.

Ok, I'd like to take a stab at this, here is what I think they are:

Track 1 has the jitter errors
Track 2 the higher noise floor
Track 3 is the original

Bren, I can't disagree with anything ya said there.

Again, I think it's a great effort. And I DID throw that cheap player out!

That's because - whatever number of errors in a row or per track or weak DAC or whatEVER it takes - there was no doubt that (during the musical conditions I described before)I could hear a difference between THAT player, and my XCD88.

I'm not saying it's a $2000 difference - but the better hardware, a hefty case, some cool features, etc., and the very subtle but better sound - it IS worth $200 more - to me!

Chess - I agree with the "grains of sand" thing too. I'm not one of those people either. But - while those moments of music are rare for you, perhaps, they are common for me. That IS what I listen to - as much Mozart as Metallica. I'm fairly diverse.

One random point to ponder - nothing cracks me up more than an "audiophile" in my house picking on "sonic discrepancies" that can't tell me if a piano or guitar is out of tune, or if the singer was on pitch.

"Strive for better quality recordings..." Absolutely. Without that, nothing else matters. I have no interest in accurately reproducing other people's mistakes!

Anyway - I still think it's a cool idea - thanks for the effort.

"Any "mod" which would actually cause an audible change would therefore be by definition a degradation of sound quality."

The above is a statement of opinion. ("degradation of sound quality"). Quality? Huh? If the mod leads the user to enjoy the sound, it is an improvement. Who wants "perfect" sound if it sucks? This kind of statement is also irrelevant when applied to home audio equipment in an environment which can't even come a million miles close to a real live experience, ie, getting "perfect sound" doesn't really matter anyways.

If the "sound quality" is moved closer towards reproducing the performance, then it's "better" by anyone's book. If you prefer to modify the sound to suit your preferences, then it's "different" - and "better" to some but not to others.

In general, the "live performance" (having seen a few - and participated in a few) - is rarely - almost never - as good as it is in my living room. Sure, the "ambiance" and so forth is unrivaled, but I could say that for a Larry the Cable Guy CD too. The balance, the mix, the artist's intentions - these are usually better in my living room.

Live performances are full of "soft" edges from echo, errors by performers, gear that malfunctions, and people that scream over my favorite parts. NOTHING is like a live performance, no doubt. But it doesn't usually sound "better" if you define "better" as "closer to what the songwriter hoped you'd hear."

Having said all that - if the recording sucks, then, yeah, I wanna hear it that way. Anything else is cheating!

Casaba - I won't spoil the fun yet with an "answer key" but rest assured, I will provide one soon (probably next Monday as I'm heading out to NeverHappy's neck of the woods tomorrow)

Bren R.