Technical debate

[LICORNE]

I'm proposing for those interested to start a technical information debate on Altec achievements in their products versus competing companies.

Such topics as the Mantaray horn versus all other CD horns .


The only True duplex system versus coaxial
speakers.

The front loaded horn cabinet vertues.


Jim Dickinson wrote quite an eloquent and acurate rendering on the VOTT.

.....................................

[Old Guy]

What's your definition of "the only true duplex"?

There are a number of manufacturers with the horn thru the magnet assembly.

[LICORNE]

Could you name one please.

It has to do with more than a hole through the magnet. Often imitated, but never duplicated, the ALTEC 604 DUPLEX?has been heralded the world over for its ability to reproduce sound accurately and in proper phase. It is still the BEST sounding point-source loudspeaker in existence today.
Just look at these specs.

http://www.altecpro.com/pdfs/vintage...%20Speaker.pdf

The same can be said about the Neumann U47 tube Mic. There are lot's of imitations. But that is all they are immitations.
Most of their parts don't come near to the real thing. I think the same can be said about Altec Duplex 604 The parts and crafstmenship cannot be reproduced or copied by other manufacturers because of their lack of understanding of a long process and evolution that only Altec Engineers
can understand.It evolved through cinematographic
need to reproduce sound.That is why Altec is knowledgeable and still in the forefront.Just one example: The underhung voice coil instead of overhung. Try explaining that to the new generation.

.......................

[Old Guy]

Okay- if you want to have a debate- first thing is you can NOT change the rules in the middle.
You said the "only true duplex" No mention made of quality.

P Audio is an easy one to look up:

http://www.paacoustic.com/Product_De...ctID=BM-12CXHC

Beyma, B&C, and at least a dozen other manufacturers make similar designs.

Altec did not make the last 604's they marketed. They were Great Plains speakers. So Altec doesn't currently make higher quality Duplexes.

I am not arguing that P Audio designs are better. I can say that 12" will smoke a 617, which is a fair comparison.

Truthful statements:

The Altec was the SECOND true duplex style.

Far and away it is the most successful.

Probably the most desired.

Not true-

The Altec is the ONLY duplex speaker.

[LICORNE]

I can only compare the two in a static mode.

The main criteria to judge a speaker is it's
efficiency vs cone displacement.

http://www.altecpro.com/pdfs/vintage...%20Speaker.pdf

For the Altec 604-8H
Sensitivity is 100 DB 1WM
X max .15 inches stays inside the gap no overhang.

Beyma
Sensitivity 98 DB 1WM
X Max .20 inches going outside the gap "overhang".

To get the extra 2DB you have to quadruple power of the amp which explains why it's rated at 300 watts.

Since Altec remains inside the gap and is truly an underhung voice coil. This makes it a more efficient speaker by far.

............

[Old Guy]

To get an extra 2 db you have to quadruple the amp?

[Todd W. White]

What do you mean it wasn't the first?

[LICORNE]

I'll have to compare tomorrow.
I must say it's quite powerfull but only gives you 96 Db if I remmember at 1 watt one meter.

Theres plenty of headromm for Dynamic range material.

It's got to be an overhung voice coil which makes it less acurate than an Altec Duplex.

......................................

[LICORNE]

A speaker 0f 65 watts will give you 100DB+20DB=118DB

A speaker of 300 watts with 98DB +28DB =126DB


The extra 20 Db comes from an amplifier of 65watts for the Altec 604-8H.
The extra 28DB comes from an amplifier of 300 Watts for the Beyma coax.

Convergence

..........................................

[Old Guy]

Actually, referenced to 1 watt, 20 db is 100 watts.

300 watts would be about 24.5 db by my calculations.