Altec 420A Biflex listening impressions

[tgroendahl]

Can anyone kindly tell me about this wide range drivers way of reproducing? I have been considering the 420A for my system, eventually with the addition of a hf horn driver above 10Khz. From the T/S parameter list, I have learned that Qts of the 420A is .49 which should make it suitable for an open baffle set-up. My system: 2A3 SET amp + EMT 930 tt. I listen mainly to classical and jazz music. I like the idea of a fullrange- or widerange driver in an OB. Thanks in advance for any help. Thomas

[bfish]

Thomas,

I have no personal experience with any of the biflex models, but there's some basic info on these unique speakers in the Unofficial Library, and there's some more detailed info in the patent for them. (Do a patent number search on the US Patent office site for 2834424).

I'd be curious to hear someone's firsthand application experience myself. Was it an 'Edsel', or another ingenious design that just never caught on? I'm having trouble grasping how the mid-suspension could simultaneously couple and uncouple, which would be required for complex musical signals.

[Jim Butler]

For a year I had a pair of Santanas as the mains in my livingroom. They were switched out for model 8's and a LF-1 subwoofer so I haven't heard them first hand in a while... but... my recollection was they had amazing midrange clarity. I always thought the phenolic tweeter in the Santanas was pretty bad (kind of grating), but the mids produced by the bi-flex, particularly voices was great (my wife used to comment on how well she could hear TV sound at low volume because of the clarity). Since the Santanas and similar Altec cabs for the 420 were relatively small, I suspect the woofer never had a chance to play as deeply as it was capable. If anyone knows the proper cab dims for full 420 bass extension, I'ld love to know.

[zelgall]

Apparently, there are two or three types of 420's. I have a pair with 16" frames and Alnico magnets which I had in a 10cuFt box with a ribbon tweeeter or in a combo with a Goodmans 12" tri-ax. Both sounded very good. On a 4' x 4' sheet of plywood, they were also OK but needed a sub. They also had a 15" frame version and one with a tweeter hanging off a metal strap across the frame. I've heard neither of these but they seem more common on Ebay.

[LICORNE]

Hi,

I found 2 models of 420 Biflex.

420 a 15"
420 b 16"

If they were all allnico ? I don't have that information .

The enclosure of the Santana was sealed.

There was also a 12" version the 419 biflex.

[zelgall]

There's also a 420Y with the tweeter.

[LICORNE]

They all have the HF tweeter above 2500 HZ as descibed previously.

420 a 15"
420 a 16"
420 b

[zelgall]

The Santana has a tweeter, yes. I believe that only the 420Y has a tweeter built into the same frame. It's mounted on a bar across the frame of the 420Y. Others, like my 16" 420A have no tweeter. I wonder why Altec kept the same model number with both the 15 and 16" A's.

[LICORNE]

Hi
Well I think one reason had to do with the old die cast. Altec got new cast and decided to go 16"
. I guess it's a transion period.So you had inventory of 15" and 16" .

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[LICORNE]

Hi,
The Santana had a XO at 2500 HZ. Please see the info below on cabinet dimensions