A lot of those differences are *due* to differences in freq response, WHICH IS THE DIFFERENT LEVEL OF A PARTICULAR PART OF THE FREQ SPECTRUM AS COMPARED TO ANOTHER PART.

Plus, you could also say that hey, a lot of those differences are due to phase differences inherent in *most* (not all) speaker manufacturer's designs.

(Phase variance is also created any time a "filter" is applied to the audio signal. Crossovers, low/high pass filters, "cinema eq" etc.)

The problem? Only Vandersteen, Thiel, and Dunlavy, among a very few others, actually make "phase coherent" and "time aligned" speakers. So... if phase (and time alignement too) mattered that much, then people wouldn't be buying B&W, Paradigm, NHT, etc.

Speakers are a different matter annyway, simply because of how they interact with the room.

But, for source components and pre pros/receivers, I believe that the differences that people can actually hear between quality components are so small as to be meaningless. (DSP algorythms are different, just straight stereo, 5.1 DD, DTS, etc.)

And as for people who can hear the differences between *quality* solid state amp designs under normal operating conditions? More power to you, but I think you're fooling yourself. Now, if the amps are driven *hard* enough to detect the nature of their failure ("catastrophic" or "graceful"), that is also different.

A *lot* of people consider amplification a commodity. Not a lot of difference between quality amps.

And I know this from experience. Have had Acurus amps for quite awhile. 100x3, then 2 200x3's, and now 2 A200x3's. Liked 'em so much I tried their big brother the Aragon 8008x3. Big and bad and beautiful power amplifier. But after 30 days? Couldn't detect any difference so stuck with the Acurus.

This is a philosophy thing. I believe what I believe, and you entitled to believe what you want to believe.

Bottom line is that I don't go chasing component after component because I believe I'm going to get that much more benefit in sound quality. (Digital vs analog *does* matter. Analog rules. But differences between DACs in *quality* components *of the same technology generation*? Ain't going to convince me that matters. But I still want 24/192's... )

I go for ergonomics, quality of construction, manufacturer reputation, reliability, features, remote considerations. I put heavy duty consideration into the reviews I read, even if I don't believe all the sound "quality" differences that are noted. But because the professional reviewers out there do come across a hell of a lot more componenets than I ever will, so judgements of all those other items that I look at will be included. I also put heavy duty emphasis on audioreview.com. If a sizeable proportion of the actual *owners* of a product like it, more than likely I will too.

But of course, ymmv, and it will...

Yer foolin' yourself if you think you can reliably calibrate sound levels without a sound meter. Can't remember the source, but I read an article several years ago that demonstrated the need for this to be accurate.
They took a room, with two 5.1 setups. One was a high end speaker system (can't remember the brand). The other was a set of cheapo Rat-Shack small speakers. The RS speakers were calibrated to within 1 db. The others were left mismatched, but still within a small range (can't remember, something like 2-3 dB). Both sets were hidden from view by acoustically-transparent screens.
The participants consistently picked the RS setup as having the more convincing soundfield.

Note, this doesn't mean the best, most detailed sound. When watching a movie, you can have the most revealing setup in the world, but if pans change in volume or character as an object moves, say form left to center to right, the illusion is broken, and you hear the speakers instead of the movie sound.

So, if we can't even reliably calibrate speakers by ear to within 1 db, how can anyone be trusted to know that Amp A sounds 'more detailed' than Amp B, when they heard them on different days, different speakers, etc??

Today, any quality differences between high quality amps are largely neglible. The interaction between a given amp and a given set of speakers is far more important. All speakers have a widely varying impedance across the frequency spectrum. For example, my Martin Logan reQuests are 'nominally' 4 ohms. But, this impedance drops to as low as 1.2 ohms at some freqs -- damn near a dead short! This drastic change is enough to alter the performance of some amps, and even make some give up completely. So, even though an amp meets certain specs, it may fail when hooked up to systems like this.
So, while I might prefer Amp A over Amp B in my system, I don't think this applies to all other systems. Likewise, of the set of Amps that can handle difficult loads like MLs, I think the sound difference is very marginal, if audible at all.


[This message has been edited by bigmac (edited August 04, 2002).]

Good post Kevin. I'd have to say I pretty much agree with you.

I have to say I don't trust anybody's judgement on sound quality for multichannel output (even my own) without the use of an SPL meter.

And yes I completely agree with this statement:

I must say, that changes what I think about everything azryan has said up till now, and tends to make me take all his statements with a big grain of salt.

[This message has been edited by bstan (edited August 05, 2002).]

I see here, and on other boards, that users either "prefer" the analog RS meter, or go as far as saying that they are "better" or "easier to use" than the digital meter.

I have a digital RS meter, primarily because they were sold out of the analog meters the day I bought mine. To use it, I set the range at 70, the weighting at C, and the speed to slow. Then I simply adjust the volume until the inch high numerals read 75 for each channel - Pretty easy for me.

I'm not trying to start a "Tastes better-Less filling" argument over preferences - Other than the analog meter being about $10 cheaper than the digital meter, what else, if anything, makes the analog meter "better" or "easier to use"? I'm sure some folks prefer the analog because it is more like the kind of equipment they are used accustomed to using, but I fail to see where that makes it better or easier to use for an inexperienced purchaser to use.

Any thoughts?

Thanks!

AHwww. Its a digital READout!
Your post made me wish I went digital. The numeric read sounds great and the way you describe the rest sounds like it works just the same. When I asked the RS employee to tell me the differences between the two.. He could not tell me stated he did not understand them and had never used them. So I went with the less-expensive buy, since I've spent enough lately and knew the analogue was in use to satisfaction, by many.

Since the analogue meter screen has no hash marks for smaller increments. Sounds like your digital would be more accurate.

bigmac,
One... since you don't know the source, I'm sorry but your example is totally pointless.
Who knows how that test (if it even existed as you wrote it) was set up?

I'm sure I would have picked the system that was set closer to correct over the one you said was set wrong on purpose if asked which had the more balanced/solid surround field.

This doesn't prove that the SPL meter calibration method was more accurate than by ear. This test has nothing to do with debating that issue. The test (as you described it) is only showing that a level matched system is important to a surround set up.

I totally agree with this.

Personally I use a 4.1 system w/ Newform Research speakers in phantom center mode (not that I recommend this set up for everyone, but more speakers doesn't simply mean better).
This creates an inherently perfectly matching center in both tone and volume to my mains. Panning is inherently perfectly seamless also in my system, and with my rear Newforms ~110 degrees behind dead center the surroundfield level matched by my ear is also seamless within the general 'sweet spot' of the couch.

Matching the sub is much tougher of course. I use dual DIY sonotube subs in the same corner of the room. I have the phase flipped on them to blend into the mains that are ~6' from the nearest walls, and floor to ceiling bass tube traps to cut up the standing waves (which would otherwise distort my ear's judgement AND and SPL meter's reading).

Since the rat shack SPL meter is so inaccurate on bass (and yes I know about the correction chart), I prefer to judge by ear the blend of bass on many diff. tracks of CDs and DVD's -which all have diff. levels of bass mixed anyway, so no 'one' level is ever going to be exactly right in any system.

I certainly would like to set this even more accurately if possible, but it can't be done.

Ever hear a combo DD/DTS DVD w/ diff. surround/sub levels on your system? One's closer to right than the other, even though both are on the same SPL level matched system. But which is right no one can say. Take your pick. Your 'preference' won't be wrong.

Look at the advice of steves (who believes he disagrees with me)...
He says level match w/ SPL meter (ignoring my point being that you can't know you have correctly done this), and THEN tweak your system by ear per source, defeating the whole point of claiming that level matching w/ the SPL meter is so critical!
He then explains how a properly calibrated system should generally sound. Which I think everyone here agrees with, and no one is questioning. Questioning his grasp of my debate points.

Wow,
Sad.
Ok, some of your disagree w/ me. Fine..., but then you neglect to actually explain how I'm wrong -making your opinions baseless and flaming. You can do better than that can't you?
bstan. You made just enough effort to post a generalized insult as to the quality of ALL my previous posts? Low. Very low. And quite without a leg (or fact based point) to stand on.

Here's the plain and simple version of my two main points.
"There's a TON of variables involved in level matching your surround system w/ an SPL meter, and NO consensus as to exactly how to do it."
and
"Beyond this, there's many other huge factors that more than counter any sincere efforts to calibrate you system w/ an SPL meter".

Many of the variables I posted have already been posted in this thread by others. By people who are very much in favor of SLP meter calibration, yet don't see these variables as any kind of a flaw in the process actually being accurate.

Like I said -I'd LIKE to be in favor of SPL calib. myself.
I've got a rat shack 5 min. away, and enough money for the meter any day of the week. I've thought for years about getting one because of all the recommendations.

Sadly, all these MANY variables that keep cropping up (and seemingly ignored by everyone as irrelevant) make the 'calibration method' highly flawed, or at best of little sonic value even if it were perfect. -unless your ears are just awful and your own judgement of the test tone's volume is way way off.
Someone could have mentioned this in a point against me.
I concede to this being possible though, so -'too late'.

Here's one more variable (and please go back and read all the others I posted if you want to debate this with me, and leave the personal insults OUT of it. You should be able to do that.)

Do you all calibrate w/ the meter dead center in the prime sweet spot? Great, but unless you all watch movies alone, or you insist on always sitting in that 'sweet spot' you just threw off your calibration in yet another way by sitting even slightly off to one side -(and screwed up your distance settings or digital room correction systems too which are diff. issues, but in the exact same vein).

And not to change the subject but as for you who think all amps bascially sound the same. You're just flat out wrong, and none of you should then own amps that are anything but the cheapest available, or you'd pointlessly be wasting money.

My new eARTwo digital amp was instantly FAR FAR better than my previous and long broken in Audiosource digital AMP7 -in every way. My wife and I were both shocked at the difference. It's incredible how much better my 950 sounds through it. And the 950 certainly not the best sounding front end in the world -great as it it.

And compared to my amp before that, my AMP7 had a much tighter/faster low end, slightly more recessed midrange, and faster, more transparent yet slightly less smooth highs. This is at at any point in normal volume range so don't fool yourself that level matching played any part in the issue either.

Azryan, Tsk, Tsk, is it because its Monday?
You know I am the first to declare (regarding myself) I DON’T KNOW NUTing hardly yet. But I’ll pick up the gauntlet for a quick point. I find it enlightening that you have never used a meter, and personally I think you should add that in as pertinent tidbit, when discussing the merits thereof. I see your theory, and I see very valid arguments for your points. Particularly in regards to all the variations using a meter has to account for. After all, we did make our first shots to the moon, all based on understanding parameters without having first hand experience of them yet.

But I’ll take it on faith that you and your wife hear a difference when you added in your new amplifier, (and I believe). If you’ll take it on faith that my husband and I heard a difference (for the better) after calibrating our speakers.

..these results may not be representative of everyone choosing to follow our diet plan, and did include a weekly regimen of exercise

You might want to re-read what I said, which was- IF you wanted to tweak the levels. I don't. Most folks only make small level adjustments to the center and/or sub. By the way, a phantom center is great as long as there is only one (or two of you close together) occupying the "sweet spot". Having a center speaker works much better as it will anchor the dialogue and central sound effects way better for people sitting "off-center". I do like a "phantom center" when I'm listening to two-channel music.