DIY Jensen Compact Back Loaded Corner Horn

CornerHorn

New Member
Hey guys this is my first time posting but I thought I would share with you all the cabinets my grandfather and I made. I'm very interested in hearing the opnions on our speaker choice. Please keep in mind that we used what we had and the reproduction quality has smashed through our best expectations. We have a JBL 076 IER catseye radiator for HF and it's companion LE5-9 with waveguide for mids, now for the LF we couldn't afford to pony up for a D130 so we went with what we had, a 15" Carvin PA speaker. I believe it's model number to be PA-150? Anyways that PA speaker hasn't missed a beat and I couldn't be more surprised at how good it sounds. Also we are using the crossovers from a set of Sansui SP-2500's which are also working surprisingly well. A Denon DRA-545R is providing 65 watts of quality stereo signal to both. Our source of choice is my LG V10 with a 32bit DAC and a library supplied by Tidal HIFI. Can't wait to get feed back on these please be gentle as these have been my baptism into HiFi lol0521170058.jpg 0521170058.jpg 0521170059.jpg 0521170058.jpg 0521170059.jpg 0521170100.jpg 0521170058.jpg 0521170058.jpg 0521170059.jpg 0521170100.jpg 0521170058.jpg 0521170059.jpg 0521170100.jpg
 
Do you have any photos from different angles on the speakers.
I'd be interested in looking at them
 
You certainly dived right in and they look great, the concept is really good but I would look into having someone design you a custom crossover if possible, not me they are a mystery.

The JBL 076 IER & LE5-9 are gold and a matched pair, JBL have the appropriate crossover for them, here is the schematic, you just need to have someone design the part for the PA-150 if you want to go that far.

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Thank you very much and I now owe my newly discovered passion and hobby to my grandfather, I also owe him for the huge lesson in cabinet making this project gave him the opportunity to teach me. We have the crossovers from the L220 unfortunatly time has not been very kind to them and was the motivating factor in using the Sansui crossover. Is it easier to repair the L220 crossover then to build one from scratch?
 
I should have stated that these are still in a phase of construction and are by no means considered finished. We still have to decide on a design for the HF/MF enclosure, dampening material still needs to be added and will be an evolving project over the next couple years. But they sound awesome and have truly given me a understanding of fidelity.

Here is the L220 crossover for those who may be skilled in the way of the schematic. Also the correct model number is PS-15 for the Carvin woofer.

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Greetings and well done work. 'dampening'? or open faced.. so some experimenting can be done but usually I like open faced like yours. (only thing is little fingers like 'cats or kids' curiously poking at the drivers. Your grandfather has the mind for the built in greater than 45 degrees of music 'arc'. So praises to him!
 
Thank you everyone for the kind words. My grandfather is a retired cabinet maker with 30+years experience. So we feel confident to tackle some more complex cabinets. If I could find solid plans for a K Horn I am confident that we could build them. Our next set tho is going to be the Jensen Corner Imperial. My Grandfather built one in the 80's and has had the itch to do a set of them.
 
I'm assuming you guys went straight off the 1952 plans for the Jensen corner horn? Looks great !

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That's a fantastic-looking build, buddy! I love the old designs, and I love big speakers, so your build is right up my alley.

I would certainly agree with the others that you will likely be much better served with the JBL crossover. Not because the Sansui piece is no good, but the JBL will give you the recommended crossover points and slopes. And, in most cases, the only thing you need to do to the JBL is replace the capacitors. They are the only thing that can go bad.

Do you plan to veneer the cabinets? Those would look seriously attractive in a nice veneer.

GeeDeeEmm
 
We started with the 1952 plans but quickly discovered that the dims where deceiving. So I found a Russian forum that had revamped plans of this cabinet. Heads up to anyone who attempts these off of the 52' plans you will never get that 90 degree angle with these dims. Thank you for the kind words everyone glad you enjoy them as much as we do.

Dampening the inner baffle behind the woofer. From what I've read it tricks the sound wave into behaving as tho it's in a larger enclosure.

We are going laminate these with a high pressure laminate. A dark wood pattern more then likely. We are also discussing the shape for the grill cloths
 
We started with the 1952 plans but quickly discovered that the dims where deceiving. So I found a Russian forum that had revamped plans of this cabinet. Heads up to anyone who attempts these off of the 52' plans you will never get that 90 degree angle with these dims.

Good to know. Web link ??
 
I'll try and find the link but if you type in "Jensen BLH" in Google and look for a CAD drawing of these that's the site.
 
Dampening the inner baffle behind the woofer. From what I've read it tricks the sound wave into behaving as tho it's in a larger enclosure.

Check me on this because I could be totally off base, but I believe that damping (not "dampening," which refers to moisture) the enclosure to make the woofer "see" a larger volume is primarily useful in the realm of acoustic suspension (sealed) enclosures.

In the case of a horn or reflex cabinet, the ports are tuned to a specific woofer reacting in a specifically-sized enclosure with specific tuning. I think that altering the perceived volume of the enclosure would throw off the tuning.

The primary purpose of damping material in a tuned enclosure is to break up standing waves that would otherwise find their way back to the woofer. That's why a number of designers, especially in the "classic" enclosures, typically used fiberglass batting or panels on only one of two parallel surfaces, typically on the back panel, one side panel, and the bottom panel at a minimum. (Of course, some used no damping, while others used it on all interior surfaces except for the motor board.)

Others with much more knowledge than I will correct me if I'm wrong.

GeeDeeEmm
 
Lol thank you for the correction. I believe your correct about damping in vented enclosures. However I have read that in folded horns the compression chamber I believe it's called, the baffle directly behind the woofer Is encouraged to be dampened. If I remember correctly it helps to reduce standing waves from cone resonance. I'm sure I am not explaining this correctly but I'm gonna hedge my bet on the wisdom of other members.
 
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