Can I convert a 909 to a 902?

**SOOTSHE** · May 31st, 2010, 07:57 PM

I have 2 Altec HF drivers.....a 902 8A and a 909 8A. Will they be the same if I put the same diaphragms in them?

The bodies look identical to me, except the 909 has some sort of rubber ring around the circumference.

**Old Guy** · May 31st, 2010, 09:39 PM

I have to admit not being as familiar with 900's...does the 909 have the loading cap?

If so I would assume the same mods as an 808 needs?

Just curious...

**bfish** · May 31st, 2010, 10:39 PM

Measure the outlets, I suspect you'll find the 902 to be 7/8", and the 909 a full 1". If so, even if they're equipped the same, they'll be different.

**SOOTSHE** · May 31st, 2010, 11:13 PM

I measured the outlets & they are both 7/8 inch & they both have the orange tangerine phase plug.
I found this info.....does this give any clues?

**SOOTSHE** · May 31st, 2010, 11:17 PM

Originally Posted by Old Guy

I have to admit not being as familiar with 900's...does the 909 have the loading cap?

If so I would assume the same mods as an 808 needs?

Just curious...

The 909 I have has no loading cap.

**RonSSS** · June 1st, 2010, 04:19 AM

The 909's had Pascalite frams, the 902's didn't.

ron

**whitebroncoii** · June 1st, 2010, 02:09 PM

The answer to your question is "yes".

If your 902-8A looks exactly like your 909-8A, they are both from the same period where the 902, 908, and 909 were all built using the same motor and the only difference was the diaphragm.

The rubber bumper was installed on drivers sold alone. The drivers used inside of speaker systems did not normally have a rubber bumper and often did not have a back cap (this saved a few manufacturing dollars).

There were times when drivers were pulled from finished stock and installed in speaker systems. Of course these would be complete assemblies.

**robertbartsch** · June 1st, 2010, 04:42 PM

Yeh, Altec did some weird stuff back then. For example, I'm rebuilding some 846B Valencia cabs whose serial numbers are close. One cab has a bottom square bracket that sits on the floor that is made from one inch plywood and the other is compressed sawdust (MDF).

**Old Guy** · June 1st, 2010, 05:23 PM

Originally Posted by whitebroncoii

The answer to your question is "yes".

If your 902-8A looks exactly like your 909-8A, they are both from the same period where the 902, 908, and 909 were all built using the same motor and the only difference was the diaphragm.

The rubber bumper was installed on drivers sold alone. The drivers used inside of speaker systems did not normally have a rubber bumper and often did not have a back cap (this saved a few manufacturing dollars).

So the 909 did generally come with a cap then? Am just assuming so because the back cover couldn't be left off without it?

**SOOTSHE** · June 1st, 2010, 05:27 PM

Originally Posted by whitebroncoii

The answer to your question is "yes".

If your 902-8A looks exactly like your 909-8A, they are both from the same period where the 902, 908, and 909 were all built using the same motor and the only difference was the diaphragm.

The rubber bumper was installed on drivers sold alone. The drivers used inside of speaker systems did not normally have a rubber bumper and often did not have a back cap (this saved a few manufacturing dollars).

There were times when drivers were pulled from finished stock and installed in speaker systems. Of course these would be complete assemblies.

whitebroncoii,
Thanks for that....saves me having to try to find another 902. Will organise a couple of new diaphragms & I'm ready to go.