How often is >20k cut? speakers that go > 20K?

[jeff_free69]

The motivation for this thread is really for a discussion about speaker design -ie does anyone really need tweeters that go to 30k?

Some points made were that 99% of popular recording microphones don't even go that high. And of course, the limitations of the CD format. (Not to mention problems those of us who grew up on Led Zeppelin might have - but lets assume perfect hearing out to ~ 20k)

The counter-arguments include SACDs, which could extend past CD. And there are some mics like sanken that go out to 30k (though you don't usually see them in the favorites list of anybodys mic cabinet)

I have noticed that, at least for ITB mixing & mastering, some engineers filter out the "digital shmutz" above 20k, just like one would do below 20Hz.

So how common is it to do this? Is it sacred ground?

[Cheebs Goat]

I dunno. I'd imagine that if you were designing a speaker to be as flat as possible at 20 kHz and it just happened to end up flat to 30-40 kHz, you wouldn't nerf it to only go to 20 kHz. At least some of those high speaker ranges are probably byproducts of simply trying to make a flat speaker.

[manman]

does anyone really need tweeters that go to 30k?

Yes mate, u need a tweeter that goes up to 100kHz. Rupert Neve himself stated that his console allow high bandwidth pass through up to 200khz . Even SSL channel equalizer have low pass filter starting at 50kHz.

Real cymbals, and other instrument produce ultrasound harmonics thats why you get realistic sound.

I believe having a speaker that goes at least up to 35Khz is crucial for sound in general, we are in modern world that requires higher resolution for audio, video etc..

Same thing with the bass. Passive speakers can go up to 1hz at low frequencies. Active speakers sometimes have high pass filter on at 30hz which degrades overall quality.

Cutting any bandwidth may affect natural perception of recording. Problem is what converter produces any frequency above 20kHz? lol

[jeff_free69]

At least some of those high speaker ranges are probably byproducts of simply trying to make a flat speaker.

Thats pretty reasonable - a speaker that is
a) flat response and
b) low distortion
may very well also happen to
c) extend to 25-30k.

a & b aren't all that impossible to achieve. The question is that given a driver that does a & b, does C) really matter?

I agree that under purist conditions it could matter, but in practice?
I don't have any major ME equipment, but my Manley Matering EQ plugin has a low pass switch with settings like 25k, 30k etc.
I'm curious to know what the pro's here do. I know one answer boils down to the usual "when it needs it"; but looking at the big picture, how often or rare is it that it does?

[dcollins]

Originally Posted by manman

Yes mate, u need a tweeter that goes up to 100kHz. Rupert Neve himself stated that his console allow high bandwidth pass through up to 200khz.

That may be true of the new Neve, but the ones that made classic records were not flat to 200kHz.

Real cymbals, and other instrument produce ultrasound harmonics thats why you get realistic sound.

Instruments producing >20kHz sound and needing it for realistic sound are not the same thing.

I believe having a speaker that goes at least up to 35Khz is crucial for sound in general, we are in modern world that requires higher resolution for audio, video etc..

Do your mics go up to 35k? The great majority of speakers sure don't.

Same thing with the bass. Passive speakers can go up to 1hz at low frequencies.

Where do you get this idea?

Cutting any bandwidth may affect natural perception of recording. Problem is what converter produces any frequency above 20kHz? lol

Well, any converter running at 44.1 does not. Ones used at higher sampling rates certainly can.....................


DC

[Ron Vogel]

I swear you can find anything on the web:

Acoustic Trauma : Bioeffects of Sound

[Chrisc_o]

Originally Posted by jeff_free69

I have noticed that, at least for ITB mixing & mastering, some engineers filter out the "digital shmutz" above 20k, just like one would do below 20Hz.

ITB=digital.

Don't all digital converters depend on a steep LPF just below the maximum frequency for the converter's sample rate (i.e. around 20khz for 44.1khz)?

I'm pretty sure they do, and if they do then it happens more often than you may realize. The stuff above 20khz will be chopped off by the converter (at 44.1) before you have a say in the matter.

[Nordenstam]

Originally Posted by manman

I believe having a speaker that goes at least up to 35Khz is crucial for sound in general, we are in modern world that requires higher resolution for audio, video etc..

Same thing with the bass. Passive speakers can go up to 1hz at low frequencies. Active speakers sometimes have high pass filter on at 30hz which degrades overall quality.

For the ultimate in extra-sensory nirvana, try marrying such a sound system to a visual kit sporting the ability to record and reproduce infrared and ultraviolet light.



Joking aside, there's no reason to produce sound pressure we can't hear (or feel, unless turned to insane levels). Though it's certainly a good idea to avoid smeary filters of various sorts. Cutting close to audiofrequent band must be done with care. A bit of leeway is nice to have!