Excellent results! I'm sure Zilch would be proud.
I need to get mine up and running. I need to make new baffle boards for the EV SP-12 drivers I'll be using in these with JBL 2404 baby-cheeks tweeter horn should work out pretty good!
Regards, Ron
I need to get mine up and running. I need to make new baffle boards for the EV SP-12 drivers I'll be using in these with JBL 2404 baby-cheeks tweeter horn should work out pretty good!
Regards, Ron
Wow, Beautiful !!!
I know Zilch would be real happy with how this all turned out . Great, great work Wilberforce .
Nice Project !!!
<. cheers, EarlK
ps;
A high efficiency setup like this ( @ 99-100db ) would have represented somewhat of a test case for the EWaves' HF compensation network .
- ( To see if the driver had sufficient HF content to still allow for linear response in the horn circuit after padding the midrange ) .
- It's doubtful that older Legacy drivers ( like Altec or JBL ) on a true Constant Directivity Horn could be properly ( HF ) compensated ( & not lose too much efficiency ) .
- No wonder Zilch was so interested in "Priming The Pump" on this one ( so to speak ) .
- He always did like a challenge . RIP
Sorry for the ramble, 😱 😛
I know Zilch would be real happy with how this all turned out . Great, great work Wilberforce .
Nice Project !!!
<. cheers, EarlK
ps;
A high efficiency setup like this ( @ 99-100db ) would have represented somewhat of a test case for the EWaves' HF compensation network .
- ( To see if the driver had sufficient HF content to still allow for linear response in the horn circuit after padding the midrange ) .
- It's doubtful that older Legacy drivers ( like Altec or JBL ) on a true Constant Directivity Horn could be properly ( HF ) compensated ( & not lose too much efficiency ) .
- No wonder Zilch was so interested in "Priming The Pump" on this one ( so to speak ) .
- He always did like a challenge . RIP
Sorry for the ramble, 😱 😛
Wow, Beautiful !!!
I know Zilch would be real happy with how this all turned out . Great, great work Wilberforce .
Nice Project !!!
ps;
A high efficiency setup like this ( @ 99-100db ) would have represented somewhat of a test case for the EWaves' HF compensation network .
- ( To see if the driver had sufficient HF content to still allow for linear response in the horn circuit after padding the midrange ) .
- It's doubtful that older Legacy drivers ( like Altec or JBL ) on a true Constant Directivity Horn could be properly ( HF ) compensated ( & not lose too much efficiency ) .
- No wonder Zilch was so interested in "Priming The Pump" on this one ( so to speak ) .
- He always did like a challenge . RIP
Sorry for the ramble, 😱 😛
I just wish I could add some data rather than my subjective 'wank.' After we finished up the first one, I was tempted to drive it up to Zilchlab so he could measure it. Obviously, that didn't happen, but my only measurement system, my ears, are very, very pleased with these speakers, and that's enough for me.

I got a request by PM to post the cabinetmaker's improved version of the 1952 Jensen plans. Here they are:
Note: The original design and these sketches don't have the overlay on the top and bottom that my old cabinet had. I asked Bob (the cabinetmaker) to add these after he had made these sketches. I like the look; makes it more finished looking, like a mantelpiece or something. So if you want that, just add 1/2" or however long you want the overhang to be on the front and sides of the top and bottom pieces. This is what it looks like.
Also not in the sketches is the false bottom. It's basically in the shape of the cabinet, but not closed at the back. It's 1 1/2" high and recessed 4" back from the front. I think it helps the bass from getting too muddy.
Second request was for the final crossover components that were fine-tuned by Zilch:
Dayton DNR-16 16 Ohm 10W Precision Audio Grade Resistor
Part Number: 004-16
Dayton DNR-30 30 Ohm 10W Precision Audio Grade Resistor
Part Number: 004-30
Dayton Audio DMPC-4.7 4.7uF 250V Polypropylene Capacitor
Part Number: 027-422
Dayton Audio DMPC-12 12uF 250V Polypropylene Capacitor
Part Number: 027-430
Jantzen 3.9uF 400V Crosscap Capacitor
Part Number: 027-922
Jantzen 0.60mH 18 AWG Air Core Inductor
Part Number: 255-234
1.5mH 18 AWG I Core Inductor
Part Number: 266-552
L-Pad 50W Mono 1" Shaft 8 Ohm
Part Number: 260-255
Any other questions, let me know. I'm loving these speakers.





Note: The original design and these sketches don't have the overlay on the top and bottom that my old cabinet had. I asked Bob (the cabinetmaker) to add these after he had made these sketches. I like the look; makes it more finished looking, like a mantelpiece or something. So if you want that, just add 1/2" or however long you want the overhang to be on the front and sides of the top and bottom pieces. This is what it looks like.

Also not in the sketches is the false bottom. It's basically in the shape of the cabinet, but not closed at the back. It's 1 1/2" high and recessed 4" back from the front. I think it helps the bass from getting too muddy.
Second request was for the final crossover components that were fine-tuned by Zilch:
Dayton DNR-16 16 Ohm 10W Precision Audio Grade Resistor
Part Number: 004-16
Dayton DNR-30 30 Ohm 10W Precision Audio Grade Resistor
Part Number: 004-30
Dayton Audio DMPC-4.7 4.7uF 250V Polypropylene Capacitor
Part Number: 027-422
Dayton Audio DMPC-12 12uF 250V Polypropylene Capacitor
Part Number: 027-430
Jantzen 3.9uF 400V Crosscap Capacitor
Part Number: 027-922
Jantzen 0.60mH 18 AWG Air Core Inductor
Part Number: 255-234
1.5mH 18 AWG I Core Inductor
Part Number: 266-552
L-Pad 50W Mono 1" Shaft 8 Ohm
Part Number: 260-255
Any other questions, let me know. I'm loving these speakers.
I got a request by PM to post the cabinetmaker's improved version of the 1952 Jensen plans. Here they are:
Note: The original design and these sketches don't have the overlay on the top and bottom that my old cabinet had. I asked Bob (the cabinetmaker) to add these after he had made these sketches. I like the look; makes it more finished looking, like a mantelpiece or something. So if you want that, just add 1/2" or however long you want the overhang to be on the front and sides of the top and bottom pieces. This is what it looks like.
Also not in the sketches is the false bottom. It's basically in the shape of the cabinet, but not closed at the back. It's 1 1/2" high and recessed 4" back from the front. I think it helps the bass from getting too muddy.
Any other questions, let me know. I'm loving these speakers.
i have a pair of JBL E-145 15" drivers. they are the LE15 predecessors. wonder how these might work in the cabs?
i have a pair of JBL E-145 15" drivers. they are the LE15 predecessors. wonder how these might work in the cabs?
I bet they'd sound good. SPL = 98 db. Plays up to 2.5 hz. Why not?
.... and to think, you were only going to have the one box.
Yes, Zilch would be proud...
I like to think so. He was a great help.
And yes, it was going to be the 50's mid-fi mono rig. But it just sounded too good to stay mono. BUT! I still have the original black beast that I found on craigslist, and I'm hunting around for a vintage coaxial driver to stick in the original baffle. Then, I'll have the mono rig that I was originally going to have.
I've been looking at the University 315C, as Altec 604 and Jensen G610 are going for way more than I want to spend. Anyone have any thoughts on the Universitys? I tried an Electro-Voice 15TRXB, but wasn't very impressed with it.
greetings wilbur, thanks heaps for that. By the way what thickness ply did you use? cheers fergs
greetings wilbur, thanks heaps for that. By the way what thickness ply did you use? cheers fergs
I think it's 15 mm. Russian birch multi-ply.
I got a request by PM to post the cabinetmaker's improved version of the 1952 Jensen plans. Here they are:
Note: The original design and these sketches don't have the overlay on the top and bottom that my old cabinet had. I asked Bob (the cabinetmaker) to add these after he had made these sketches. I like the look; makes it more finished looking, like a mantelpiece or something. So if you want that, just add 1/2" or however long you want the overhang to be on the front and sides of the top and bottom pieces. This is what it looks like.
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Also not in the sketches is the false bottom. It's basically in the shape of the cabinet, but not closed at the back. It's 1 1/2" high and recessed 4" back from the front. I think it helps the bass from getting too muddy.
Any other questions, let me know. I'm loving these speakers.
by overlay do you mean "over hang", in that the top and bottom extrude beyond the front and sides of the vertical parts of the cabinets?
can you provide a photo of the "false bottom"?
thanks.
by overlay do you mean "over hang", in that the top and bottom extrude beyond the front and sides of the vertical parts of the cabinets?
Yes.
The false bottom (it is closed in the back, I was thinking of the EV Regency):
An externally hosted image should be here but it was not working when we last tested it.
Greetings, parts express are out of the 1.5mH 18awg I core inductor. Will an air core inductor of the same value and awg do, such as part no. 260-255? Sorry for the remedial questions but I was up the back of the class with Wilbour scratching my name into the desk. Also where do people get thier qsc cd horns and what actual model is it. Will the JBL one be the same? I was considering using the B&C de-250 as most people seem to theink that its much smoother than the selenium220ti. I wonder how it compares to the selenium 2500. Unfortunately PE has run out of the de250's so I have to wait anyway. cheers fergs
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Greetings, parts express are out of the 1.5mH 18awg I core inductor. Will an air core inductor of the same value and awg do, such as part no. 260-255? Sorry for the remedial questions but I was up the back of the class with Wilbour scratching my name into the desk. Also where do people get thier qsc cd horns and what actual model is it. Will the JBL one be the same? I was considering using the B&C de-250 as most people seem to theink that its much smoother than the selenium220ti. I wonder how it compares to the selenium 2500. Unfortunately PE has run out of the de250's so I have to wait anyway. cheers fergs
The QSC waveguides are scarce now. I'd suggest searching or asking your questions on Zilch's Econowave thread here:
Zilch's AK Design Collaborative - Econowave Speaker - AudioKarma.org Home Audio Stereo Discussion Forums
This is a pretty cool design. Who wouldn't like to have their 15" drivers mounted in a pair of these?
What if the center triangular piece was omitted completely?
You would effectively lose over half the length of the folded horn, which would make this box useless.
any idea what the angles are here? they appear to be 30, 60 and 45, but might be fractional?
also, has anyone determined the LF extension of this cabinet? probably about -3db @ 30hz?
I have no idea, either angles or LF extension, but I'd like to know the latter. I don't have any measuring equipment--is there a modeling program for folded horns?
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