J-Low

[Duggeh]

Wasn't sure about putting this in the DIY or speaker forum, I suspect that nobody much minds anyway.

I'm keen to put together a pair of big silly horns to go with my big silly stats. The obvious go-to options are the J-Low and the Kleinhorn, but tragically the Kleinhorn is a couple of inches too tall to fit in my room (and nothing like as simple to glue together). The standard J-Low is *small* enough to be built and then moved into the room through the door in one piece. But! I'm tempted by the notion of scaling the build up bigger and assembling it in the room (full height of an MDF sheet is 8 feet and my ceiling is about 9.5). Back of the envelope maths tells me that scaled to 8 feet high the speaker would be 31 inches deep and 33.6 over the front.

What do the HC team think? The more silliness the better I think, so long as its not hugely expensive or difficult to put together. Is there some other design I should take a peek at?

[cetoole]

I wouldn't scale speakers, especially horns, without very carefully considering what the implications to the response will be. Doing so would totally change the tuning.

[Duggeh]

This is what I was uncertain about, because the proportions are the same. So my brain tells me, intuitively, that it'll work even better as you'll just gain more efficiency and bass. But I don't even pretend to be able to understand horn geometry concepts. I just really like the idea and wanted to find out if I was in fact mad for even considering it.

Thinking on it further weight might turn out to be a factor. Adding what might turn out to be 400KG of MDF onto a second floor has me with visions of The Great Race, where Professor Fates house falls down.

[cetoole]

You have to take into account the wavelength of the sound and stuff too.

[bhjazz]

I just read a bit about the J-Low. I had no idea of it before. One thing that stuck out to me was, this comment:

"...The JX92S’s didn’t go any lower in frequency than before but they picked up about 10 dB of gain centered in the 70 Hz region, and in fact became bass heavy."

I'm not sure I'd like to go through that much cutting and gluing only to find that the driver wasn't going to stand up to what I was expecting. So to speak. It seems like there are going to be a lot of calculations first before you even get to power up the saw.

Can you get a better driver for this so you can achieve some vomit-inducing bass? That would be pretty cool. The bass, not the vomit.

[Duggeh]

Nelson pass has said in response to inquiries about building the design with a larger driver "try it and see". Putting an 8 inch woofer-midrange in the box and adding a second driver inside the top mouth could be doable. More drivers means more money though.

[mypasswordis]

Are you going to be building the F1 transconductance amp in conjunction with this horn build? And I'm not so sure about using multiple drivers on a horn build, but maybe one of your design goals is not to have it be full-range with one driver all the way through.

Here is an interesting patent for you, with a bit of stuff on design physics: Back loaded folded corner horn speaker - Patent 3923124

[MASantos]

If I'd be building this, I would use Nelson's exact specifications and measurements for the cabinets since AFAIK, he did some testing on them to make sure they sounded good! Diverging from the original design either in size and/or driver choice could be a disaster sound wise! Or maybe you could come up with a new great sounding horn!

[Knuckledragger]

I hear it has a good bottom end.

[luvdunhill]

Duggeh, any interest still in the project?

[Duggeh]

Sensible consideration of the practicalities made me abandon it. Maybe in the future.

[luvdunhill]

Sensible consideration of the practicalities made me abandon it. Maybe in the future.

drat. Maybe something on a bit smaller scale?

[Duggeh]

I just want to stick with getting more from the Soundlabs, rather than proliferating already limited space and finances with another set of speakers with drastically different amp requirements.

[luvdunhill]

ah. double drat.. you and your logic.