Altec 2 Way Build ala JELabs - 802/32/414

Me likey.

What woofer?
Jensen P15LS which seem to be P15LL designated for heathkit.

12471

I previously had Altec 414z's, in the same config as the jelabs. I'll be using the Jensens (and 32 /802) with Salectric's crossovers this time.
 

Pboser

Junior Member
I finally cobbled together my open baffle version of this speaker. Sounds great to start, even crammed in my son' s bedroom for testing and domestic tranquility purposes.

The woofers are courtesy of Early Bender of HiFiTown, and the 902-8As that I got on ebay with only one diaphragm have been brought to life through the intervention of Bill at Great Plains Audio. I'd also give credit to the guy who sold me the baffles with 12" openings if I could remember his name. Thanks to JRob for the simple one-cap crossover idea (still playing around with different values and types). And of course thanks to Joseph (je2a3) for the suggestions of the driver combo AND the baffle design.

At the moment I'm just playing Spotify through a Chromecast Audio, into the thundering 2 watts per channel of the ugly cobbled together breadboard (I guess I have an issue finishing projects) Boozhead Labs 6C45P PP amp. The horns are level-controlled by the Niles transformer volume control - allows for experimentation. And the caps are connected in the traditional manner, using high-end audiophile-approved clip leads.

This thread is fun and inspiring. Please jump in with any suggestions, etc. Happy Saturday!

PeteIMG_1358.jpgIMG_1359.jpgIMG_1361.jpgIMG_1362.jpgIMG_1363.jpg
 

Thermionics

Post Whore In Training
Where the heck do you find Altec 32b/32c horns? They seem to be as rare as hen's teeth. Is anyone making a replica?
 
Where the heck do you find Altec 32b/32c horns? They seem to be as rare as hen's teeth. Is anyone making a replica?
I believe auditorium 23 /ligno lab did make them but azzolini audio do make them and are 3d printed.

Much cheaper to keep an eye on ebay though. The consensus seems to be the plastic ones have the better throat...
 
The consensus seems to be the plastic ones have the better throat...
I'm actually midway through the process of modifying a pair of cast aluminum 32's to optimize the throat. Original WECo 32's had 3/4" inch throat opening (for 713 driver), and hence needed a longer horn path to achieve proper expansion when compared to a native 1" throat horn. When Altec got hold of the metal 32's, they just bored them out to 1" to mate with 806/802 type drivers, but the problem is there's a bit of the throat (from where it was originally 3/4" to where the horn expansion would naturally open up to 1") that has parallel sides--in fact, that bit is cylindrical (which can't be optimal for horn expansion). Furthermore, Altec bored them at a slight angle, so now you have the smooth expansion inside the driver meeting, at an abrupt angle, a cylindrical section of horn before continuing on with the calculated expansion. I'm guessing this can't be optimal. When Altec made the plastic 32's, they reconfigured them as native 1" throat horns, which is why they're a little shorter than the aluminum ones.

Since I had a pair of aluminum 32's laying around, I went nuts one day and cut the "extra" inch or so of bored throat out of them, and am having the driver mounting flanges re-welded onto the now shorter horn. When I'm done, the expansion inside the driver will transition smoothly to the horn expansion, meeting where the horn naturally expands to 1".

Could all be total BS, and a waste of a perfectly good pair of aluminum 32's, but I think not. I'm optimistic it will be a noticeable improvement.

Will update here as warranted.
 
Joe83- Would love to hear your description of 15" vs 12".

The 32/802 and woofer combo is sooo flexible. You can do 12” or 15” woofers in open baffle, 3- 6cuft cabs, ported, closed.

I like to think of them like the Tannoys dual concentric. Very similar in that it’s a simple 2-way and crosses over around 2k. Tannoys have all the combos mentioned above and then some. But 32/802 combo is miles better than the Tannoy upper end. They are just as coherent but they sound more sophisticated and dynamic w better dispersion. Jazz horns are no contest better on the Altecs.

And super easy DIY... if I can do it, then....

My suggestion to eveyone is to use your imagination and experiment.

For ex... Woody- Plop that 32/802 on top of the Onkens, hack into the xover, and see how it goes.
 
Will do once its done and all settled in!
Are you going to use Sals boost network? I'm interested in your R values there. I ended up goosing mine pretty high, so it seems.

Let me check tonight and I'll let you know what mine are. I forgot, my 802's are 16ohm... will need to convert for comparison purposes.
 
Are you going to use Sals boost network? I'm interested in your R values there. I ended up goosing mine pretty high, so it seems.

Let me check tonight and I'll let you know what mine are. I forgot, my 802's are 16ohm... will need to convert for comparison purposes.
Yes, I did have 16 ohm but one diaphragm needed replacing so I went with 8 ohm to keep it simple.
 

Thermionics

Post Whore In Training
I believe auditorium 23 /ligno lab did make them but azzolini audio do make them and are 3d printed.

Much cheaper to keep an eye on ebay though. The consensus seems to be the plastic ones have the better throat...
I've got ebay searches in place, but these horns seem to be going for crazy money (e.g. $700+).
 
I've got ebay searches in place, but these horns seem to be going for crazy money (e.g. $700+).
Hmmm. That may be the original Western Electric. I might pay the freight on those if I was trying to build a "driver" correct 753. It has a longer throat and may be better with the WE 713cd. The Altec versions should go for around $2-300 a pair... that is if this thread isnt bumping up the price. You used to see them on ebay about every other month if not more frequent but I havent seen any lately.

I wouldn't sweat it too much between the metal or composite version. I have both and I think the difference is negligible. Not the easiest thing to A/B. But if there is any difference in sonics its probably just a bit different and not "better". I ended up with the metal one just becauase I think they look cooler.
 
Top