Shielded compression drivers

[bmar]

Greetings,

I would like to purchase a Shielded compression driver to use with a horn in a center channel speaker.

1 3/8 screw would be best but not limiting.

any place something like this is available would be most helpful.

thanks,

Bill

[TBrennan]

Bill--Any old Altec or JBL Alnico magnet driver is shielded. These use an Alnico slug magnet inside the driver, the iron return structure that forms the body of the driver focuses the magnetic field into the gap area and the result is a shielded driver (though the shielding was not the intent), a paperclip won't stick to one of these things. Find a used driver on ebay or at Jammin Jersey, local pro shops may have one lying around. Try Altec model 802 or 806, JBL model 2420, 2420, LE-175 (same as 2410) or LE-85 (same as 2420). All these drivers use aluminum diaphragms and have extended highs, tweeters are not needed unless they are used on constant directivity horns in which case EQ or tweeters are needed. Crossover no lower than 500hz.

[bmar]

Thanks Tom,

I have some 807-8 i will have to give a try. if those are not alnico I will be on a hunt! I called Klipsch in hopes to purchase a horn driver from a RC-7 or the like. they are not for sale so I was told.

Bill

[TBrennan]

Bmar--You're home free, the 807 is Alnico.

[bmar]

T- You are the man!

I waved it around the TV with no ill effects. I was originally going to use this driver but had passed it up because the 811 horn it was on, I decided was a little large for a center speaker. (for now)

just ordered a new bolt on horn lense that will replace the CH3 I had used. might still need to ad a small bullet for some extended high end twinkle.

I have a few other center speaker and this one is by far much better.

Thanks,

Bill

[TBrennan]

Bmar---Nice, very nice, no doubt it sounds very good. If you want to add a little sparkle you can change out the diaphragm in the 807. The 807 used Altec's "symbiotic" high power handling diaphragm, compared to the plain aluminum one used in the 806 and 802 it's said to lack a little on the top and has slower transients. Personally I've never compared but this is the conventional wisdom among Altec enthusiasts, Altec themselves did rate the driver as having less extension. A Radian brand aluminum replacement diaphragm will do the job or get a diaphragm fom Bill Hanuschek at Great Plains Audio in Oklahoma. Bill was Altec's last head designer, when Telex killed the company Bill bought the tooling and he makes original parts on the same machinery using the same methods. Send the driver to Bill and he'll remagnetize (Alnico can lose magnetic strength over the years, especially if a driver has been overpowered) and rediaphragm it for about $100, that's one bargain. Radian diaphragms are about $50 each and are easy to install and sound VERY good, I've used them in Altec and JBL drivers. But note that some think that even the best 1" metal diaphragm drivers are a little shy on top, I don't, but it's a matter of taste. Checkout the Altec info at www.soundpractices.com and look at www.radianaudio.com