MAH vs LOW OHMS

THE NEED FOR EXTENDED HIGH FREQUENCY BANDWIDTH -OR WHY YOU NEED A SUPERTWEETER

http://www.hilberink.nl/tannoy/tsupertweeter.pdf

GM

Quote:

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Originally Posted by tomt

Made his own recordings.

With an electrostatic microphone.

That i would like to hear more about.

In another thread ...

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Nope, Right here:

Start with the following URL, and I'll try to find a AA post, a shot of him recording, in a URL #2 to follow, will edit this post.


Audio Asylum Thread Printer


Twenty One minutes later, found URL #2:


Audio Asylum Thread Printer



Jeff Medwin ........Low Ohms

Very cool link that GM posted. Thanks for that.

Seems like there is a lot going on past 20khz. Especially with percussion instruments.

But will our Altec drivers actually reproduce that?

You say Bob Fulton had a driver coming in at 42khz. I would bet money it wasn't an Altec 802:D

So do we need a supertweeter to reproduce those frequencies?

It has been known for many years that some instruments produce sound beyond 20Khz but not usually fundamental frequencies . It is also known that two PURE tones,f1 and f2, will interact, producing sum and difference frequencies, Combination tone - Wikipedia. The energy in these tones is usually diminished unless exploited by deliberate filtering or enhancement - physical or electronic.

The content above 20kHz is lower in energy and tends to be not musical in terms of scales and significant timbres. The ear is not particularly discriminating outside of voice frequencies(except for perception of source placement) unless attention is focussed narrowly. The interaction of frequencies is very broad and occurs everywhere in the source material and the room at all frequencies. The fact that most of the energy in the post 20kHz region, harmonics/hash, is very low and masked by the overall higher energy of the main program content makes it not significant to humans. Your dog may hear it but likely as a confusing irritant.

You can test it by recording pure multiple tones of different frequencies, up to 50khz, and add them to a recording at the correct relative levels and see if there is difference.

Quote:

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Originally Posted by Elitopus1

Very cool link that GM posted. Thanks for that.

Seems like there is a lot going on past 20khz. Especially with percussion instruments.

But will our Altec drivers actually reproduce that?

You say Bob Fulton had a driver coming in at 42khz. I would bet money it wasn't an Altec 802:D

So do we need a supertweeter to reproduce those frequencies?

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and i wasted good money on 4 of the 1310 super tweeters. I just gave up on them because anything over half volume they became decorations. :D

Quote:

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Originally Posted by BillWojo

As posted by Jeff:

"But she could detect instantly ( through resultants in the midrange ) when something was wrong, when 42 kHz and 80-110 KHz were taken out of the play-back chain "

So what kind of drivers was he using to play up in those frequency's? What recordings did he use that had information up there, what instruments play up there and how was this all done? Jeff, my BS meter is pegged off the scale at this point. Actually, I think you bent the pointer!

BillWojo

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Bill,


Here is a photo, Early 1980s , most wideband speaker ever produced to my knowledge. Fulton Premiere P-12. Five-way tweeter module.



Mass - Loading Speakers, for Extra Performance gains - drlowmu - High Efficiency Speaker Asylum


Have you ever seen or heard one of these ?? Set up well??

Its in my office, my co-worker uses it. I gave them to him.


Jeff .... Low Ohms

Quote:

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Originally Posted by Elitopus1

Very cool link that GM posted. Thanks for that.

Seems like there is a lot going on past 20khz. Especially with percussion instruments.

But will our Altec drivers actually reproduce that?

You say Bob Fulton had a driver coming in at 42khz. I would bet money it wasn't an Altec 802:D

So do we need a supertweeter to reproduce those frequencies?

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You're welcome!

Yes, just at very low amplitude due to the diaphragm's mass rolling off its HF output at 12 dB octave beginning around 7 kHz, so already down 18+ dB/20 kHz. The super tweeter would need to be a piezo array for HIFI/HT, but the problem is there's no consumer recordings that go > ~22.05 kHz AFAIK.

GM

Sorry I didn't see this sooner ! This board is not about personal disputes between members it is about All things ALTEC ! PERIOD !

This is not going to be tolerated any longer ! Todd will be by shortly ! Thread closed and please refrain from posting these kinds of threads in the future they will be deleted immediately !

Thread has been quickly edited. I tried to leave any useful or technical information.And edited all snarky comments,characterizations,etc.. Out of the thread.Todd and I discussed that if the snarky comments continue between members.Those members involved will be placed in the Moderated usergroup . Meaning those members won't be able to post until a Moderator reviews each and every post by that member and is OK'd by a Moderator before posting to the board.That would really SUCK ! So please think before you post your comments,because it is getting tiresome !

LONG LIVE ALTEC LANSING !

All this reminds me of when I joined the corporate world; I was told I only needed to practice three things to get along:

live by the golden rule

keep your words soft n' sweet just in case you have to eat them

be kind, considerate to those you pass on your way up the corporate ladder in case you have to pass them on your way down

GM