I've built a pile of Unity horns over the last few years, but haven't been 100% happy with any of them. (I like making speakers more than finishing speakers.)
An issue I had in 2019, is that my 3D printer couldn't make waveguides that are very large.
I bought a flashy new 3D printer, and it absolutely sucks. It's horrible. Possibly the worst 3D printer I've ever owned. (Creality CR10 if anyone's curious.)
Due to all these issues with 3D printing, I had the idea of doing a hybrid. Basically taking an existing waveguide, 3D printing a 'plate' to mount the woofer to the waveguide, and then make a crossover for the thing.
An issue I had in 2019, is that my 3D printer couldn't make waveguides that are very large.
I bought a flashy new 3D printer, and it absolutely sucks. It's horrible. Possibly the worst 3D printer I've ever owned. (Creality CR10 if anyone's curious.)
Due to all these issues with 3D printing, I had the idea of doing a hybrid. Basically taking an existing waveguide, 3D printing a 'plate' to mount the woofer to the waveguide, and then make a crossover for the thing.
Test Bench: Eminence N151M-8 1” Compression Driver | audioXpress
https://www.eminence.com/pdf/N151M-8.pdf
great HF performance but recommended crossover 1.8kHz could be tricky to hit?
*also whats the wave guide? it looks like it should have excellent constant directivity behavior and has nice flat walls!
https://www.eminence.com/pdf/N151M-8.pdf
great HF performance but recommended crossover 1.8kHz could be tricky to hit?
*also whats the wave guide? it looks like it should have excellent constant directivity behavior and has nice flat walls!
Seems to be available in USA:
B-52 PHRN-1014 1" Horn 10" x 14" Bolt-On
and cheap.
*Also available from ebay using international shipping program for non-USA:
B-52 PHRN-1014 10" x 14" Plastic Horn Waveguide | eBay
(I ordered 3...)
Last edited:
Parts Express appears to have fewer than 10 pairs left in stock. Go try and order 20 units and see what happens.
They are, indeed, cheap. And an excellent value. In addition to performing very well, they are quite well made. The QSC was a little better (it had a provision for a backside gasket) but it's history.
They are, indeed, cheap. And an excellent value. In addition to performing very well, they are quite well made. The QSC was a little better (it had a provision for a backside gasket) but it's history.
The main reason I used the QSC waveguide is because it's a ridiculously good match to the Eminence. If you look down the throat, I'd argue the Eminence is a much better match than the Celestion that QSC used themselves. It's like the QSC waveguide was designed for the Eminence! It's wild.
The QSC waveguide has been cloned at least twice:
1) PRV Audio cloned it, around eight or nine years ago: PRV Audio WG35-25-B 1" 90 x 60 ABS Waveguide 2-Bolt
2) The B52 waveguide is the *exact* same thing. Not clear if they cloned it, or just bought a pile of them from PRV.
Considering that Parts Express has stocked this off and on for ten years, I wouldn't be surprised if they were willing to have a run of them made. Someone at Parts Express must know what factory these came out of. And if you look on Aliexpress or Alibaba you can get a good idea who made it.
The QSC waveguide has been cloned at least twice:
1) PRV Audio cloned it, around eight or nine years ago: PRV Audio WG35-25-B 1" 90 x 60 ABS Waveguide 2-Bolt
2) The B52 waveguide is the *exact* same thing. Not clear if they cloned it, or just bought a pile of them from PRV.
Considering that Parts Express has stocked this off and on for ten years, I wouldn't be surprised if they were willing to have a run of them made. Someone at Parts Express must know what factory these came out of. And if you look on Aliexpress or Alibaba you can get a good idea who made it.
In it's stock form, I don't see any issue getting down to 1350Hz or so. I've measured it with a single midrange on the waveguide, and I had to "pad" the Eminence down by about 15dB just to get it to match with the midrange.
It takes two watts for the N151M to hit THX levels.
It was actually the Jericho J7 that inspired me to start using the Eminence. In the pics of the Eminence, I thought it was mostly a clone of the BMS 4552ND, but the Eminence is actually quite a bit bigger. And my thought was that bigger might be better. For $90 they're a steal.
Side by side:
It'll be a three way.
Picture an Econowave Deluxe:
In a nutshell, when you have a two way with a center to center spacing of about 300mm, you get a really strong narrowing of the vertical beamwidth at the crossover point.
Is that audible? Debatable. I had a set of Yamaha DXR12s in my living room, and they have a center to center spacing that's about that bad, and the DXR12s sound great.
But the Unity horn seems to improve the articulation and percussion sounds noticeably better.
So it seemed like a worthwhile endeavor to go from two way to three way.
I came *really* close to just going two way, and I know that Sheldon has mentioned that he doesn't notice a big difference between running his Unity horns in two-way versus three way. (I'm too lazy to look up his post.)
Then again, IIRC, both of the Lambda Unity Horns that I've heard had the TAD upgrade, and a TAD compression driver can go way lower than this $90 Eminence.
Picture an Econowave Deluxe:
An externally hosted image should be here but it was not working when we last tested it.
In a nutshell, when you have a two way with a center to center spacing of about 300mm, you get a really strong narrowing of the vertical beamwidth at the crossover point.
Is that audible? Debatable. I had a set of Yamaha DXR12s in my living room, and they have a center to center spacing that's about that bad, and the DXR12s sound great.
But the Unity horn seems to improve the articulation and percussion sounds noticeably better.
So it seemed like a worthwhile endeavor to go from two way to three way.
I came *really* close to just going two way, and I know that Sheldon has mentioned that he doesn't notice a big difference between running his Unity horns in two-way versus three way. (I'm too lazy to look up his post.)
Then again, IIRC, both of the Lambda Unity Horns that I've heard had the TAD upgrade, and a TAD compression driver can go way lower than this $90 Eminence.
Here's some measurements of the N151M on the QSC, which I did four months ago: https://www.diyaudio.com/forums/multi-way/350889-improved-lens-3.html#post6122375
Last edited:
Nice work Patrick. I wonder if those port injection holes are a bit undersized though and you may get some compression losses or the velocity will be too high through them. If you remember about 4 years ago, I did a similar thing with an LTH142 waveguide by printing a woofer adapter with internal volume filler cone. I used a 2.5in fullrange cone instead of a CD for the tweeter though and this let me cross at 600Hz instead of 1.5kHz as typical of CD synergy horns. Your waveguide has advantage of a flat wall. The LTH was curved and required a carefully made 3D model of the back side horn wall to fit properly. That was a pain to do.
A Bookshelf Multi-Way Point-Source Horn
I used a piece of plywood for the driver mounting face though.
It measured pretty well too:
I just got a new 3D printer too - haven’t tried it yet but reviews are very good. No futzing with settings on Dremel model 3D45.
A Bookshelf Multi-Way Point-Source Horn
I used a piece of plywood for the driver mounting face though.
It measured pretty well too:
I just got a new 3D printer too - haven’t tried it yet but reviews are very good. No futzing with settings on Dremel model 3D45.
Last edited:
Oddly enough, this entire project nearly got cancelled because of Microsoft:
I 3D printed the adapter, and put everything together, then measured it. Looked really bad.
Put it back on the shelf.
A few days later I came **this** close to putting it in the trash. I have a really bad habit of never finishing anything, and it doesn't take much to convince me to throw a project away.
But I decided to give it another go, another round of measurements. I started to notice that they just looked inexplicably bad. For instance, there were was way more echoes in the measurement than you'd expect with a proper gate.
I tried different USB ports, different volume levels. I came really close to disassembling my microphone, but decided that would probably break it.
I upgraded the drivers on my sound card. Rebooted a few times. Still crummy.
Finally, as a last ditch sanity check before buying a new mic, I tried a different computer.
Everything worked fine.
So it looks like the geniuses at Microsoft have added some type of new "feature" to Windows ten that's trashed my ability to use the microphone.
A long, long time ago, like 20 years ago, I had the same problem with Windows XP: Microsoft would randomly make changes to the microphone and sound card settings with no rhyme or reason. For instance, there were some "features" that would screw up the microphone input in subtle ways.
Windows 10 barely has any user accessible settings for the mic at all, so this is really irritating.
I think I may have to install Windows 7 just to get this stupid PC to behave properly. Or possibly get an external sound card.
It's seriously aggravating because I didn't make any changes to my PC, it just upgraded itself, like it constantly does. (Yes, I know you can turn off updates, but I kinda like having the O.S. up-to-date.)
TLDR: I can't do distortion or polar measurements at the moment, unless I drag another PC to the garage.
I 3D printed the adapter, and put everything together, then measured it. Looked really bad.
Put it back on the shelf.
A few days later I came **this** close to putting it in the trash. I have a really bad habit of never finishing anything, and it doesn't take much to convince me to throw a project away.
But I decided to give it another go, another round of measurements. I started to notice that they just looked inexplicably bad. For instance, there were was way more echoes in the measurement than you'd expect with a proper gate.
I tried different USB ports, different volume levels. I came really close to disassembling my microphone, but decided that would probably break it.
I upgraded the drivers on my sound card. Rebooted a few times. Still crummy.
Finally, as a last ditch sanity check before buying a new mic, I tried a different computer.
Everything worked fine.
So it looks like the geniuses at Microsoft have added some type of new "feature" to Windows ten that's trashed my ability to use the microphone.
A long, long time ago, like 20 years ago, I had the same problem with Windows XP: Microsoft would randomly make changes to the microphone and sound card settings with no rhyme or reason. For instance, there were some "features" that would screw up the microphone input in subtle ways.
Windows 10 barely has any user accessible settings for the mic at all, so this is really irritating.
I think I may have to install Windows 7 just to get this stupid PC to behave properly. Or possibly get an external sound card.
It's seriously aggravating because I didn't make any changes to my PC, it just upgraded itself, like it constantly does. (Yes, I know you can turn off updates, but I kinda like having the O.S. up-to-date.)
TLDR: I can't do distortion or polar measurements at the moment, unless I drag another PC to the garage.
Ah I see we have already discussed the N151. It looks good, I will have to see how it copes with higher power levels for PA. One thing I do notice with the BMS is that there is a peak just below 20kHz which is not present with the Eminence, could this be a resonance caused by measures taken to allow greater excursion?
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.