Which Altec compression drivers are these?

[Steve71]

Picked these up locally yesterday. Apparently they came out of Union Railway Station in Denver.

I assume the horns are Tar filled 1005b's? Any Idea what the compression drivers are? The back plate says "ALTEC Lansing Corporation Hollywood", but the labels have been painted over many, many times.

My current mid range horns are Altec Manta Ray MR-64's driven by 299 CDs with GPA 288 8K diaphragms (400hz to 7.2Khz). I wonder if these multicells would sound any better. :dont-know These things are way to heavy to be swapping in and out without knowing I'm going to get a worthwhile improvement in sound. Otherwise they will have to wait in the basement for that next project. Every home needs at least one set of Altec's per floor, right?


http://steve71.fileave.com/1.JPG

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[Tom Brennan]

I can't tell if they're tar-filled without a side or top view of the horns.

Maybe the drivers are old 288s, you might have to inspect the diaphrams to tell.

IMO no horn sounds better than the 1005 multicell.

[Steve71]

Thanks for the reply Tom. Here's a pic of the top of the horn. As you can see it doesn't have any gaps between the individual cells. Each horn and driver seem to weigh about 100-150lb. So if it's not tar it's gotta be lead filled lol.

When I get these guys out of the truck I'll take off the covers and check out the diaphragms.

http://steve71.fileave.com/4.JPG

[Tom Brennan]

Oh yeah, those are tar filled. I had to get my kid's help setting my old tar-filled 1005s with 288s atop the cabinets they sat on.

[Steve Schell]

Steve71 you've got some good stuff there. To me they look like mid to late 1940s H-1005 tar filled horns with solid brass throats and drivers of similar vintage. Since the driver decals are painted over you would have to remove the rear covers and examine the diaphragms to determine the driver model. Most likely they are 288s with aluminum diaphragms, but they could be an early version of 289 or 290 with phenolic diaphragm. How about posting some diaphragm pictures? Enquiring minds want to know!

The tar filled horns do sound really good, better than the later non-filled versions. I'm pretty sure I would prefer them over the Mantarays, but you'll have to decide that one.

[Steve71]

Thanks for the info Steve. I'll post up some pics of the diaphragms, but it might not be for a few weeks. I have to make some space in the basement & rope someone into helping me unload these.

I measured the 1005's and unfortunately they won't fit without blocking the screen. I'd love to hear them, but there would be considerable effort to set them up only to have to carry them down two flights of stairs. In years to come I'll have a larger space for them.

At any rate, since these came out of Union Train Station, I have just the song play on these guys. :D

http://www.youtube.com/watch?v=Z0HM0RtRv-E

[Steve71]

Well I've managed to get one of these beasts into the house. Hopefully this week-end I'll get them both up stairs and swap them out for MR-64 horns - at least for a few weeks.

Anyway here are the requested pics of the diaphragm. I'd say the diameter is around 3 & 1/4".

Is it safe to assume that, due to their vintage, these are Alnico magnets?

http://steve71.fileave.com/IMG_5511%20%28Large%29.JPG

http://steve71.fileave.com/IMG_5510%20%28Large%29.JPG

[Steve71]

Well I've found something with the same "Altec Lansing corporation Hollywood" markings on the back. So I guess this is an 1946 (or so) 288 driver.

Here is a link to the ebay listing. The sale is for a complete 1946 A5 VOTT, but if you scroll down there are pics of the 288 driver. In the 288 pic the label just says "288" no a,b,c etc

http://cgi.ebay.com/2-altec-A5-from1946-with-RWB-lable-288-515-1005-horns_W0QQitemZ330329135097QQcmdZViewItemQQptZVint age_Electronics_R2?hash=item4ce92697f9&_trksid=p3286.c0.m14&_trkparms=72%3A1234|66%3A2|65%3A12|39%3A1|240%3A13 18|301%3A1|293%3A1|294%3A50 (http://cgi.ebay.com/2-altec-A5-from1946-with-RWB-lable-288-515-1005-horns_W0QQitemZ330329135097QQcmdZViewItemQQptZVint age_Electronics_R2?hash=item4ce92697f9&_trksid=p3286.c0.m14&_trkparms=72%3A1234%7C66%3A2%7C65%3A12%7C39%3A1%7C 240%3A1318%7C301%3A1%7C293%3A1%7C294%3A50)

The seller is asking $2500 for the 288's if sold separately. I don't know how fair a figure that is, but it seems like I got quite a deal on mine :).

I still have not had a chance swap these out for the Mantaray /288-8K drivers.. I got side tracked with some lovely Gauss 1502 tweeters. Now one channel of my Crown D-45 is playing up, so my system in down. Listening to the 1005's might still be a few weeks off.

[analog addict]

http://i443.photobucket.com/albums/qq158/analog_addict/CIMG3797.jpg

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http://i443.photobucket.com/albums/qq158/analog_addict/CIMG3795.jpg


I have been led to believe that these are 288B's. I can't date these, but the "W" LF horns (see avatar) have 515's with 1953 dates on them....:dont-know

IMHO, these have some of the sweetest mids and upper mids around. However, they don't have the sparkle that comes with meaningful response over 12K-14KHz....

[Steve71]

Thanks for the post Analog Addict!

Those 288B's look very close but the ones I have say "Hollywood" underneath "Lansing corporation". You should be able to make that out in the second photo I posted. :)

When I hook these up I'll be crossing to a HF horn at 7.2K so thankfully any short comings in the HF range won't matter. I didn't really like the HF response of the 288-8K drivers I'm using now.

Those bass horns in your avatar look very interesting, they look to have a much smaller throat area than most of the Altec bass horns. Do you have a link to some larger pics?

[analog addict]

That my components are badged as "IPC", so I can't say if the markings will be identical.

I threw together a photobucket album with most of my Altec gear in it. There's a few things missing, like my 19's and 872B's, but most of the larger stuff is there....

http://s443.photobucket.com/albums/qq158/analog_addict/Altec/

There may be some dup's also, since I haven't had time to clean it up yet....:p

[Steve71]

Is it possible that these are actually 1003 horns? When browsing pics of the 1005b's mine look larger relative to the throat. Also these were used as public address horns in a railway station so it would make sense that they'd spec 300hz horns for speech.

Anyway here is a pic of the horn from directly above. The CD is there so you can judge scale.

BTW thanks for the link Analogue Addict, at first I didn't realize that you had multiple pages. That is an amazing collection. :applaud:

http://steve71.fileave.com/Altec%201003.JPG

[Earl K]

- This pdf document about Altecs' MultiCellular Horns (http://www.altecpro.com/pdfs/vintage/SpeakerAndMics/horns/HF%20Horns%20Multicellular%20Horns.pdf)will help you determine what model your horn is ( by comparing its' dimensions ) .

>< cheers :)

[Steve71]

Thanks Earl! According to the dimensions it's a 1003b horn. No wonder these things weigh a ton as they are considerably larger than the 1005b's.

[Steve Schell]

Yup, 1003s. You'll have better loading of the lower mids and a bit less high frequencies than with the 1005s, a very good tradeoff in my book. I have long preferred a low, +-300Hz. crossover frequency in order to have most of the vocals coming from one driver / horn combination. 300Hz. is a bit much to ask from 288s, although 375Hz. was the standard xover frequency of the Lansing Shearer systems, using a second order filter. Later on Altec changed the xover frequency to 500Hz. when the VOTT was introduced.

The actual exponential flare constant of the 300Hz. horns is lower, something like 180Hz. The old masters knew well to stay above the actual cutoff to avoid excessive response ripples. You're going to like these things. I've spent many happy hours listening to Altec 300Hz. multis, and they weren't even the superior quality tar filled ones like you have.

[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. :D

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 :p.

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. :)