BT Bashing

[pjacobi 0]

Es ist nun wirklich kein erstrebenswertes Lebensziel, über BT zu meckern. Aber erstens habe ich mein Geld für HobbyHiFi 5/00 ausgegeben und zweitens krümmen sich immer meine Fußnägel, wenn ich dort auf der Titelseite lese:

 

ooo Zitat Anfang ooo

Innovation

HobbyHiFi entdeckt:

zwei Tieftonsysteme Rücken an Rücken -

die Impulse auf das Gehäuse neutralisieren sich,

die Box steht um das 10fache ruhiger.

ooo Zitat Ende ooo

 

Nur ist das so neu nicht. Um das Beispiel zu nennen, daß mir am frischesten im Gedächtnis ist:

"Audio Physic"

 

Es gibt da ein Interview von 1996:

http://www.speakerbuilding.com/content/1039/

 

ooo Zitat Anfang ooo

Several of the larger Audio Physic speakers has two woofers mounted low on each

side of the speaker. Gerhard explains that this is done to get a low-range response

with better phase behavior.

 

- We invented this system because we wanted an in-phase signal in the bass. I

have always tried to avoid the double signal pass that you usually get from

conventional systems; with one pass going directly from the membrane, the

other over the floor and the ceiling. This placement near the floor also gives

you approximately 3 to 6 dB gain. So one of the advantages is that you can

use lower mass in the woofer and stronger magnet systems. But from 200 or

300 Hz you run into problems. You get a resonance. The magazines say that

you shall not put the woofer to the floor, because it gets boomy. But we found

that the problem in fact is in the deeper midrange region. So if you make a

very low crossover frequency, say 125-180 Hz, you can avoid this problem and

have the advantage of the room gain. Also, you benefit from the fact that the

center of the gravity is very low. The system is push-push, so the energy inside

is canceled, and the loudspeaker gets pneumatically stabilized. And the

effective baffle is large, because the woofers "see" the side of the speaker. So

you have tremendous advantages. The only problem I have found, is that the

crossover has to be very steep to get rid of the boominess.

ooo Zitat Ende ooo

 

Eine solche Box sieht man z.B.

http://www.audiophysic.de/produkte/virgo/virgo.shtml

 

Grüße,

Peter Jacobi

 

(Ich habe keine beruflichen oder privaten Verbindungen zu Audio Physic)