909s are 1"

**Phil-G** · November 7th, 2016, 01:08 AM

here's a pair for sale on ebay. there's a picture of the gasket side without the gasket and screen. I copied the pic and resized it till the studs were on 3" centers at the base. the outlet measures 1". check for yourselves

One Pair of Altec Lansing Model 909-8A High Frequency Drivers | eBay

GM · November 7th, 2016, 01:34 AM

True, what's this about?

GM

**bowtie427ss** · November 7th, 2016, 08:49 AM

what's this about?

900 series drivers have a 7/8 inch throat.

There is an ongoing debate that they made 900 series motors with 1 inch throats. Perhaps they did, but i will need more than scaling a digital image for proof positive.

It wouldn't make sense. The 900 series drivers are all shown to be the same depth.

If there was a variation in throat diameter with a constant depth dimension, then there would have to be a variation in throat angle, no?

I understand that the marketing department is a whole other ball of wax. But, would the Altec engineering dept have done that?

[IMG] 90220throat zpsfh3hm5z6

[/IMG]

**Phil-G** · November 7th, 2016, 11:12 AM

One thing I noticed when i pulled the gasket off, was the throat insert on my 902 has a 1/16 lip inside a 1" hole.
Check the photo yourself.

**Elitopus1** · November 7th, 2016, 12:12 PM

I would bet that all the 900 series were at one time 7/8" and then later (or earlier) 1". It would make no sense for only the 909 to be that way. I'm sure if you looked at enough of them you could find 1" 902 and 908 also

GM · November 7th, 2016, 01:01 PM

At least the few I had any 'hands on' experience with, the 902, 908 are 7/8", hence have a frequency BW shifted somewhat higher than the 802-8Gs, which in turn is slightly higher by design than earlier 800 series, with 909 switching back to 1". Don't recall doing anything with 906s, but assumed 7/8", so anyone know for sure what size it is?

GM

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Originally Posted by Elitopus1

I would bet that all the 900 series were at one time 7/8"........

Inretrospect, by the time the 909 came out, Altec was already down to 'making do' in some cases with what they had/could afford according to the local distributor, so no telling what they actually shipped out, especially if it was a panic replacement order for a prosound app.

Frankly, the 802-8G was the last Altec small format driver of interest to me, so recommend using more modern drivers if the older, pampered [or at least GPA rejuvenated] ones aren't in the budget.

GM