Question about A7

[weasel951]

Hello.
Hmm,is there a problem with the xo ,when i use
a 808-8A driver for HF?
I have see that the 802-8G uses a alu diafragm,the 808 a symbiotic.
Then my bass is a 416-8c,what uses M19 original?

Greetings,Andi

[cclark65]

I don't think you'll have a problem electrically, they just sound a little different.

If you get the chance, I would try a 902 driver on the horn. I bet you would be pleased. The 902-8A is the one that people say has the best HF extension, but if I am correct, any of the 902 B or T series can be made into an A series by removing the loading cap and lining the back cover with a pad of felt, but make sure it's not so thick as to touch the diaphragm!

Somebody please correct me if I am wrong.

[Altec19]

The early Model 19's used Alnico drivers (416-8B and 802-8G). Later 19's switched to all ferrite (416-8C and 902-8B). Don't ask which sounds better. You'll start a religious argument. As for the 800 series drivers, there were two basic motor assemblies (long and short) combined with several different diaphragms. The longer motor (used for the 802) is 3dB more efficient than the short motor (used for the 808) so yes, there is that difference.

As for the diaphragms, the Symbiotics are least preferable being designed to handle higher power but with poor high frequency response (HINT: you can no longer get these - and they're not valuable because of it). The aluminum diaphragm (used in the 802-8G and the 902-8B) has great sound but the lowest power handling. The later Pascolite diaphragm both sounds good and handles high power. I use Pascolite in my 19's and aluminum in my A7's and 604-8K's. I don't think you can go wrong with either aluminun or Pascolite unless you intend to run a lot of power. Then definitely Pascolite.

Also, keep in mind that the 802-8G and the 902-8B used the Tangerine Radial Phase Plug. The 808 did not.

[bfish]

Quote from Altec Fan;
"HINT: you can no longer get these - and they're not valuable because of it"

AMEN BROTHER! See how easy it would be to start a new trend?...Just think of all those shelved symbiotics we could turn into $$$ if someone spun it the other way! Glad you didn't.

I'd like to politely add that the 808-8B did have the tangerine plug, and is identical to the 802-8G, except for choice of diaphragm, loading cap, and felt pad;

Maybe when folks realize there are identical options available to the "holy grail" 802-8G, that market will become more realistic as well.

[just me now]

so what are the differences between the 802 series drivers... is the G version highly sought after solely for the tangerine phase plug?

basically what drivers can be put to 802G spec (with the proper diaphragm, removal of loading cap, felt addition)?

so far we have 808-8b

same question with the 902 series drivers....
remove the loading cap, replace diaphragm, add felt.... and turn a T into a A or B?


thanks

[Altec19]

I bel1eve there was only one Alnico motor assembly fitted with the Tangerine plug. It was used for the 802-8G and the 808-8B. That's why the demand for the 802-8G. But the 808-8B can easily be converted. It just won't have the correct label on it (if it has one at all)

You are correct about the 902 series. There are fewer combinations to consider because there is only one motor assembly.

[bfish]

Correct, and the 902 series has the same motor structure as the 909 series. The OEM versions of both simply had no rubber magnet donut or label, and with 909s, only had a loading cap and no rear cover. As with the late long-motor alnicos, the difference is largely in the choice of aluminum or pascalite diaphragms, 26420 or 34647 (for 8 ohms).

The 906 series is an entirely different unit, being a ferrite 1.4" of EV design.

[Jack6428-2]

Hello,

Does anyone know what a 909 diaphram is compared to a 902?

What 1-inch diaphrams are currently available from GPA?

Is it only the 900 series or do they still sell 800 series?

Thanks,
NG

[bfish]

There are currently 4 replacement diaphragms available to fit all Altec 1" drivers;

Aluminum (HF extension at slight expense of power handling)
34647-8 ohms
34852-16 ohms

Pascalite (Higher power handling at slight expense of HF extension)
26420-8 ohms
26421-16 ohms

Install the loading cap to limit excursion for Higher-power apps.

Remove the loading cap, and install a felt-lined rear cover for best response in power-limited apps.

There is no "best" configuration, only a best configuration for a given application.

[Jack6428-2]

Thanks bfish,

Are there any differences between what is now currently available vs what was used on the alnico 800 series drivers before the ferrite 900?s replaced them?

NG