Pro vs hifi drivers - pros and cons?

[technofreak]

Originally Posted by planet10

Only goes up to 13k?

dave

Here is a measurement. My own measurements show the same.

As for bats, according to Wikipedia (couldn't find any other information about it, lazy searcher as I am), their echolocation range is primarily limited by their pulse interval, not air absorption.

To clarify further, I don't believe in super-hyper-tweeters also, I agree that importance of frequencies above 10 kHz falls (for humans and their music, anyways). But I wouldn't say that those frequencies are absent in nature - I have fooled around with a bat detector outdoors, it was quite fun to hear all this ultrasonic noise. Up to around 30 kHz it's quite busy (crickets, grass and leaves moving in the wind etc), after that it gets increasingly quiet.

[gedlee]

Originally Posted by planet10

Last hearing test i had went up to 10kHz.

dave

My wife teaches Audiology and she told me that nob ody does tests above 8 kHz, that the standard is only defined to 8 kHz and she showed me the form, which only went to 8 kHz.

[gedlee]

Originally Posted by technofreak

their echolocation range is primarily limited by their pulse interval, not air absorption.

Sorry, but that simply doesn't make sense. I can get distance with a single pulse, I don't need a pulse interval. Thats not to say that bats don't use the interval, I can see how they would, but the interval cannot be the limiting factor.

Originally Posted by technofreak

But I wouldn't say that those frequencies are absent in nature -

Please don't misquote me, or let me correct any misunderstanding, its not that no animals or signals use the frequency band above 10 kHz, its simply that with the large air absorption, those frequencies are very limited in scope. Humans deal on a very large distance scale compared to say a small cat. Cats hear well above 20 kHz, but on their distance scale the absorption is not a big factor. For humans it is. It's all a matter of degree. Signals exist, we can detect them, but our hearing is ill equiped to utilize them to any significant degree. The obviuos reason is that there has been no evolutionary development of these frequencies because of their rarity over larger distances in the environment. Our hearing is amazingly precise in all those attributes that nature dictates would be important for survival. Above 10 kHz is NOT one of those.

[doug20]

Originally Posted by Spasticteapot

Agreed. In theory, sound quality is completely subjective and everyone has individual preferences. In reality, I find stuff that measures better sounds better nine times out of ten.



The quick answer on this one is that a driver that big is going to run into problems well before you hit 1.2khz, and a 15" woofer in a home speaker will often be able to play an octave lower with no difficulty.

The majority of PA woofers are optimized for use between 1.5khz and 100hz, where they're usually crossed over to a PA sub. In contrast, a 7" ScanSpeak woofer can easily be run from 40hz to 2.5khz.

Of course, just because you CAN run a driver this wide doesn't mean you SHOULD. Nonlinearity at excursion, intermodulation distortion, and various other issues can cause all sorts of problems

But a 7" scanspeak woofer simply sucks in terms of performance when you are considering the dynamics that exist in music or movies and . Im not a fan of compression, distortion at all so I choose better designs that can properly handle the peaks that exist in the content today.

Your quick answer about the 15" woofer having problems before 1200Hz is incorrect. You just need to realize what some QUALITY woofers can do! Linearity is incredible, distortion, extremely low and its just below the point of beaming.

Your post is a great example of over simplification. You haven't seen some of the better drivers and you might be assuming your needs are paramount. Some of us require dynamics without compression and distortion and some of us do have bigger rooms then a shoe box too!



HiFi drivers can not do that period so they are of a lessor quality then other choices like quality built pro audio drivers.

[markus76]

Originally Posted by doug20

But a 7" scanspeak woofer simply sucks in terms of performance when you are considering the dynamics that exist in music or movies

Doug, I agree with you but looking at current recordings one could argue easily the other way around. See Loudness War Explained

Best, Markus

[SY]

Slightly OT- there's some literature on the range of bat echolocation (I can post cites if anyone is interested). One factor on why the range is surprising is the astonishing SPL that the bat can produce; these have been measured as 120-133dB!

[gedlee]

Originally Posted by markus76

Doug, I agree with you but looking at current recordings one could argue easily the other way around.
Best, Markus

That most modern recordings are extremely poor is true, but really great ones do exist. I find the artists who care about their art care about how it is reproduced. One exception that I found was a terrible recording of Linda Ronstadt whom I have always had great respect for. How she allowed such a flawed recording to get out is truely a mystery to me. It may well be that she doesn't even know. Lets hope that someone actually realizes this and tthat the quality control has not degraded to the point where bad recordings get distributed without anyone even realizing it.

[markus76]

Originally Posted by gedlee

... quality control has not degraded to the point where bad recordings get distributed without anyone even realizing it.

That's already reality.

Pink Floyd "Money"



Metallica "Frantic"



Roxy Music "Avalon"



Bob Dylan "Thunder on the Mountain"



Best, Markus

[gedlee]

Originally Posted by SY

One factor on why the range is surprising is the astonishing SPL that the bat can produce; these have been measured as 120-133dB!

That explains a lot!! Quite consistant with the kind of loses that I was describing. 120 dB out, -60 dB attenuation traveling through the air, 60 dB returning to the bat. Not a problem. For humans, 20 kHz at "normal" levels of say 80-90 dB and a distance of say 10->20 meters and you have 50->60 dB - not audible for most people in most environments.

[gedlee]

Originally Posted by markus76

That's already reality.

Best, Markus

What do you base that comment on. Do you have evidence that this is the case? I put it down to distribution where the maximum perceived loudness is felt to be the most desirable attribute and that the lower sound quality that results is recognized as "unfortunate" but completely accepted as a "trade-off" to making more money. In other words they know precisely what they are doing and accept it as OK. This was the situation with "quality" at the car companies when I started. They knew exactly how bad the cars were, but they didn't care. Poor quality made more money.