Which Altec compression drivers are these?

[Steve71]

I'm using my current horns in a three way system, so a 300hz horn is preferable. In fact since I'm using a steep 24db/oct x-over I'm pushing my current horns MR-64 to 400hz. This is for home use of course and while not optimal, it sounds better to me than using a 500hz x-over. My somewhat crude RTA analysis doesn't show I'm down any at 400hz either. I know at some point I should measure my bass horn and mid range horn (outside) and then come up with a proper crossover slope based on that.

Funnily enough I've often wished for a 300hz horn since that 288 driver sounds so nice I like to use it as low as practical.

I'll post back in the next 3-4 weeks once I've got these babies up and running.

[Steve71]

I wanted to post a follow up as I've finally gotten around to installing these.

Backing up a little though, I think I've identified the drivers as 288 RWB's due to the word "Hollywood" that appears on the back.

Anyway, I've moved house since I bought these last year. The new room is large enough to do justice to these guys and I figured a way wrestle these 170lb beasts onto the bass horns by myself (which has been the cause of much of the delay).

Being that I use a dbx drive rack digital x-over it was easy to get the new horn up and running. I'm trying a low crossover (250hz to 6Khz) on these, but it'll take some mucking about until I've got them dialed in to their full potential.

Initial impressions are good, but they didn't blow me away as compared with the 288-8K's on MR-64 horns. The soundstage was the biggest difference and I *think* there was better detail making the vocals a bit easier to follow.

At extreme volume they remained smooth where the MR-64's started to get a hard edge (which I'd always attributed to reflected sound in the room).

[Tom Brennan]

Interesting.

[Steve71]

Well after a bit of fiddling around with eq, delays and x-over points, I've gotten these intergrated a lot better.

I want some time with them before I say more, but I will say they are remarkable at clapping (think Queen's We Will Rock You) and audiences in general. You could just about put an exact number on the attendance .

They're also just so freaking smooth. Maybe to a fault - they almost seem less dynamic. I guess they might need a re-mag. Is that something that would show up in the FR measurements?

[RKLee]

Can you xover over a 288 at 300 Hz? Altec recommends a 500 Hz xover for 288, and 300 Hz xover for their 290 driver. According to my altec brochure the 290 has a phenolic 'phram.

[Steve71]

For home use 300hz is no problem for the 288 as I understand it - provided that the horn will load the driver down that low.

Bill (from GPA) told me they (do/can) verify the correct installation of a new diaphragm by hitting it with a low level 20hz signal. Yeah that's not a type-o.

I'm also using a LR 24db/oct slope which also helps.

I wonder why these 300hz PA horns ended up with 288's? Did Altec make the 291 driver back in the 40's?

[Altec Best]

Nice Horns i have a pair of the tar-filled 1005's w/brass throats and they are my Favorites !!

[Steve71]

Nice Horns i have a pair of the tar-filled 1005's w/brass throats and they are my Favorites !!

Thanks AB, these guys are winning me over as well. While they do give up a few tricks to the MR's they really do have more detail. Hard to believe the sound coming out of these is from the 1940's.

IIRC you recently bought some A2 (or A4) speakers, correct? Cool to see that such majestic beasts find a nice home for retirement.