Difficult Question

[jpetek]

Hi,

do anybody understand why this speaker

http://www.vonschweikert.com/zvr11.htm

use a additional ribbon (2x Tweeter + Ribbon (>10 khz))

I do not understand.

For my option he gets a lot of problems with this large 5" Ribbon.

Thank you for your help.

regards

Josef

[Tenson]

Those tweeters have quite narrow dispersion above about 10KHz, more so than a usual 1" tweeter. I suspect the ribbon takes over from about 10KHz to keep wide dispersion.

Why he uses 2 of those nipple tweeters I don't know.... seems like a bad idea to me.

Dali use a single dome tweeter and a isoplanar ribbon. They claim it reduces IMD by using two drivers.

[jpetek]

Hi,

these driver are from scanspeak 2905 or 2904. Very good stuff.

Why they use two?

I think to get a higher output in high frequency.

regards

Josef

[Tenson]

That would only be likely is they are crossed over lower than they really should be.

It might be to keep a narrow vertical directivity, but that will not actually work at those high frequencies because the drivers will not 'couple'.

The likely answer is that it looks impressive and makes the speaker symmetrical top to bottom.

[wigginjs]

I considered that it's strictly for aesthetics although, it seems it would negatively effect the sound of the speaker unless it was simply disconnected, but really, honestly, would a speaker manufacturer that remotely values their reputation do that?

[MaVo]

IMHO these speakers are geared to look good, disregarding sound quality. I cant think of a sound quality related reason to use two tweeters.

[leadbelly]

Isn't it just a matter of efficiency? The speaker is rated 96 dB/2.83V/1m, and the non-OEM 2904/2905 are rated 94.5 dB/2.83V/1m, although I'm sure aesthetics played a major role too.

[Dave Bullet]

When you go away from a point source (that is one driver covering one frequency range), then problems with comb filtering become apparent. As the wavelength gets shorter, I always thought this becomes even more troublesome, hence why you don't see many multiple driver monopole tweeter designs.

I don't know why you need 2 revelator tweeters. surely there would be some comb filtering cancellation which would require "head in the vice" listening to get the best from these speakers.

[jpetek]

if i understand the construction right he use for each frequenz
two good driver to have more efficiency accept for the ribbion. One Ribbon is on the front and one ribbon is on the backside.

Maybe this Ribbon start at a very high frequency like 15 khz and work parallel to the two 290x?

The reason? Maybe better transperancy.