thanks to dave, the angles are drawn.
although it doesn't work on my linux system, hornresp is supposed to model horns.
Resurection
I aquired a pair of DIY corner horns made from the Jensen plans.
Back in the days of mono a local guy bought a Tannoy silver 15", and had a local furniture maker build the cabinet.
Stereo became the rage and the guy wanted in on it, but he couldn't afford another Tannoy Silver.
So he bought an Altec 15" duplex and had another cabinet made.
Like Wilberforce's 50 dollar cabinet he found, these are shorter and wider.
30" tall, and 37-1/4" wide. The depth follows along with the plans, however.
I guess the customer didn't want a 36-1/2" tall cabinet...
And then he has the cabinets mounted on 5-6" angular tapered legs?
Some sort of compromise regarding the lowboy fad of the era?
These are made from solid 3/4" Mahogany. Actual 3/4".
After some work, I'm starting off using Crites CW1526/K33 woofers, with Faital Pro LTH142 horn and HF140 driver.
A passive 2nd order network with an autoformer is used, with cut-off at 500Hz.
I have quite a bit of refinish work to do, but I really like these beasts.
(the Chinese grille covering went bye bye)
Mike
I aquired a pair of DIY corner horns made from the Jensen plans.
Back in the days of mono a local guy bought a Tannoy silver 15", and had a local furniture maker build the cabinet.
Stereo became the rage and the guy wanted in on it, but he couldn't afford another Tannoy Silver.
So he bought an Altec 15" duplex and had another cabinet made.
Like Wilberforce's 50 dollar cabinet he found, these are shorter and wider.
30" tall, and 37-1/4" wide. The depth follows along with the plans, however.
I guess the customer didn't want a 36-1/2" tall cabinet...
And then he has the cabinets mounted on 5-6" angular tapered legs?
Some sort of compromise regarding the lowboy fad of the era?
These are made from solid 3/4" Mahogany. Actual 3/4".
After some work, I'm starting off using Crites CW1526/K33 woofers, with Faital Pro LTH142 horn and HF140 driver.
A passive 2nd order network with an autoformer is used, with cut-off at 500Hz.
I have quite a bit of refinish work to do, but I really like these beasts.
(the Chinese grille covering went bye bye)
Mike
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Mike, I just now saw this. Any updates? I haven't been here for ages, I just popped in to refresh my memory on the crossover Zilch devised. My cabs are still rocking, and one of them has been pressed into duty as the center channel for the home theater rig, with my JBL 4311s serving as L and R. Just one cable swap and it's paired back up with its brother, and these days is driven by a Bottlehead Stereomour.
Post some photos of your beasts, please.
Post some photos of your beasts, please.
Good to see you around Wilberforce, your project has always been one of my favourites for this genre.
EarlK
Howdy,
This all started out when I had the parts for Crites Cornscala D, but no cabinets. Didn't have the funds to buy cabinets from Bob. So I either was going to build the bass cabinets myself, or lurk Craigslist for empty speaker cabinets that may work for the application.
An audio friend in the area listed the DIY Jensen BLH speakers on CL.
Without much knowledge on Jensen speaker designs at the time, I figured they were the proper size cabinets for 15" woofers.
Over time, you could hear bass peaking with music. Running a signal generator confirmed some nasty peaks at 300Hz and around 180Hz along with my smallish room gain at 100-120Hz. After 80Hz, roll-off seemed to drop quick.
Looking further into the Jensen plans, I figured the volume of the cabinets are more in spec with a 12" driver than a 15", being 30" tall.
That, and looking at your BLH project being much taller for 15" woofers.
So I had some Baltic Birch cut up, and then made cut-outs for 12" drivers.
The drivers I'm using for now are a CDK/AMK brand 8 ohm coaxial ceiling speaker.
They have titanium diaphragms with a round wood poplar horn, a woofer with a Fs of 45-50Hz and minimal x-max. 2.5mm or some such...
I had them in 3.5 foot internal volume cabinets port tuned to 50Hz, and I never was too fond of the bass response.
These seem to sound rather good in the BLH speakers. No weird bass peaking, just the room gain at 100-120Hz. Bass roll-off seems/sounds more extended, and still audible at 50Hz. They still boom a bit and I should play with damping to maybe attenuate the booming.
These speakers aren't really bass monsters, but they don't sound terribly rolled-off. Everything above 70Hz sounds great with the solid Mahogany being some sort of contribution I would guess. A subwoofer could help along with lower registers.
The coaxials make for good imaging and look period specific.
I recall reading a comment somewhere online about vintage speakers from this era. Where furniture quality was just as important as sound quality.
I ended up with some nice furniture like speakers and a major refinishing project for a good price. You can never have too many speakers...
But I still had parts for Cornscala D.
I did eventually find a pair of DIY Jensen BL250 Ultraflex cabinets on CL for 30 bucks. These will work for a Cornscala D variant. I already lashed them up and listened before I started to rework them.
They'll be painted black. The veneer was pretty rough...
I had a big post going, with images, and it was booted because I was too slow...
Here's the ongoing thread at AK.
BLH cabinets made from 1952 Jensen plans/plus DIY BL250 Ultraflex | Audiokarma Home Audio Stereo Discussion Forums
This all started when I had parts for Cornscala type D, but no bass cabinets.
I was either going to build bass cabinets for Cornscala type D, or scrounge Craigslist for some sort of speakers cabinets that would suit the application with regard to being bass reflex and internal volume.
The Ultraflex option should be rather close.
I do like the BLH cabinets and plan on re-finishing with new grilles...but it's going to be a chore.
Mike
Here's the ongoing thread at AK.
BLH cabinets made from 1952 Jensen plans/plus DIY BL250 Ultraflex | Audiokarma Home Audio Stereo Discussion Forums
This all started when I had parts for Cornscala type D, but no bass cabinets.
I was either going to build bass cabinets for Cornscala type D, or scrounge Craigslist for some sort of speakers cabinets that would suit the application with regard to being bass reflex and internal volume.
The Ultraflex option should be rather close.
I do like the BLH cabinets and plan on re-finishing with new grilles...but it's going to be a chore.
Mike
Thanks, Earl. I wound up reading the whole thread for the first time in years. I was so lucky with all the help I got here, especially from Zilch, who had the right answer on the first response. He is missed.
The speakers are still going strong. They're enormous beasts, not suitable for everyone, but the sound is completely different with that horn loaded bass. It's not the kind of bass that will impress anyone with a killer subwoofer, it's musical sort of bass, in that the very low over-emphasized low end that is popular these days doesn't come from any acoustic musical instruments that I know of. The horn loaded bass sounds really natural.
Cheers
Hi Wilberforce,
I see that "photobucket" has cut off your service.
Are you able to restore your photos of your fabulous corner-horns ( ie; place them here as attachments ) ?
Thanks!
Photobucket turned out to be a leaky vessel. I deleted a bunch of photos there, trying to get back into the 'free' tier, but it seems it's more of a bandwidth thing. Maybe they'll show up again next month, I don't know. That site is a mess, and I don't think I have those photos locally anymore. Sorry.
Hi,
Thanks for responding.
I saved some of your corner-horn pics ( the most recent ones of the drawings ).
If it's alright with you I'll post them here ( lmk ).
That's fine with me--post them. When I get more time, I'll sort out the photos/photobucket myself. I'd like this thread to remain as a resource for anyone else who wants to build these speakers.
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