31A horn, 730C, 27a

**Goldjazz** · May 16th, 2014, 11:02 AM

Hi All,

I just got this horn. Unfortunately I only have the one. I understand some folks enjoy listening to these. I'll be honest, I just got it out of curiosity as I'm a bit of a JBL fan and like tinkering and because it's a beautiful thing. Looking for any recommendations on how to hook it up and possibly build a mono setup.

I've owned several JBL's over the years but my experience with Altec gear is pretty limited . I did just get back from Japan where I listened to an A7 and a 604 8g (in an 620A) cabinet as well as a Urei 811c ,,,all of which I enjoyed a lot.

Thanks

**Old Guy** · May 16th, 2014, 01:20 PM

The 730C is pretty much mid only. I think it dies above 5 kHz. So you'll need a tweet.

**Altec Best** · May 17th, 2014, 05:45 PM

Yes as OG said it (730C) was only designed for vocals/PA. They are not meant for HiFi/music. The horn and attachment are Saweet.. If you can find another you would have a very expensive pair of horns.. $2500-$3000. However it seems prices have been plunging a bit lately. YMMV.

**Goldjazz** · May 19th, 2014, 07:03 AM

Originally Posted by Altec Best

Yes as OG said it (730C) was only designed for vocals/PA. They are not meant for HiFi/music. The horn and attachment are Saweet.. If you can find another you would have a very expensive pair of horns.. $2500-$3000. However it seems prices have been plunging a bit lately. YMMV.

Cheers for the reply. Just the one unfortunately. What would be a good driver to match up with the horn and throat? Thanks.

**Altec Best** · May 20th, 2014, 09:16 AM

An 802 or a 902.

**Old Guy** · May 20th, 2014, 03:44 PM

The 31A is 2inch throat. The 27 A is one-to-two inch. Designed for the 594 WE. Altec did 594B and C but you will never find one. Kinda with AB, my vote would be 802 as it will go lower and that is a big horn. I would assume a 1.4 to 2 inch would put a 288 on it.

**Goldjazz** · May 21st, 2014, 06:33 AM

Originally Posted by Old Guy

The 31A is 2inch throat. The 27 A is one-to-two inch. Designed for the 594 WE. Altec did 594B and C but you will never find one. Kinda with AB, my vote would be 802 as it will go lower and that is a big horn. I would assume a 1.4 to 2 inch would put a 288 on it.

Yeah looks like I can get a 902-8B or 802-8D's seem to be prevalent.

I see the hole patterns wont match up with the 27A, I suppose I can just make an adaptor plate? So bolt the driver to the plate and the 27a A to the plate both using screws less then the plate thickness, into tapped holes in the plate?

I see both drivers go from 500Hz up to around 20K. Will this horn behave itself and sound good all the way up that high?

**Old Guy** · May 21st, 2014, 07:59 AM

The 802 originally was a 3 bolt driver. When Altec switched to 2 piece horns, a two bolt pattern worked better. The 730 continued on as 3 bolt. After leaving Altec, James Lansing continued to use the 3 bolt for JBL designs.