Bessel functions have wide ranging applications for wave direction…..microwaves, directional antenna, radiology, etc…technology far beyond the commercial/home audio industry. There’s no construction details…….close spacing of the drivers where C to C spacing is less than or equal to the point at which the driver begins to beam is all that is required.
Not sure where the whole ‘stereo’ thing came into it….I don’t think you raised the point….each 5 element array would be for a single channel of signal………for an LCR soundbar, three 5 element arrays comprise.
I guess the thing to do if you might want a center channel later is to build it with three channels to begin with, that will save a lot of screwing around later.
So either 15 drivers in three chambers, or three drivers in the same. Figure out what 15 of what size drivers will sit nicely in 57" if you want to do the bessels, and that will get you a start on drivers. Mayhem13 sounds like they know what would be good too.
Just three drivers will be a lot cheaper though obv.
I went with sealed after trying ported and aperiodic-ish, I felt like I had a lot of bass lumping around by the wall and floor I didn't want. I wanted my attention on the screen not the bass. Vocal intelligibilty and not much bass were my goals. I live in a small apartment and I know from the other side how annoying a subwoofer can be, so I wasn't interested in inflicting it on my neighbors. Worked out.
So either 15 drivers in three chambers, or three drivers in the same. Figure out what 15 of what size drivers will sit nicely in 57" if you want to do the bessels, and that will get you a start on drivers. Mayhem13 sounds like they know what would be good too.
Just three drivers will be a lot cheaper though obv.
I went with sealed after trying ported and aperiodic-ish, I felt like I had a lot of bass lumping around by the wall and floor I didn't want. I wanted my attention on the screen not the bass. Vocal intelligibilty and not much bass were my goals. I live in a small apartment and I know from the other side how annoying a subwoofer can be, so I wasn't interested in inflicting it on my neighbors. Worked out.
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This is what I have so far have tried pretty much every 3"-5" full range driver on Parts Express with a response about 17k.
Tang Band W4-1337 seems to be about perfect but costly.
Dayton Audio DMA80-4 is also very good.
I have no idea what is considered "loud" for a television but I believe all of these would be sufficient.
Feel free to tell me how I misused WinISD.
I've only ever used it for one other project, a pair of sealed 12" subs.
I know it appears I am turning my back on the Bessel Array - I did model the PC83-4 and 8 and the math/graphs do not seem to work in their favor; cabinet volume, response, etc.
If you can show me where I went wrong with those two drivers I would consider buying 5 to play with.
Tang Band W4-1337sdf
Dayton Audio DMA80-4
Dayton Audio ND91-4
Dayton Audio RS100-4
Tang Band W4-1337 seems to be about perfect but costly.
Dayton Audio DMA80-4 is also very good.
I have no idea what is considered "loud" for a television but I believe all of these would be sufficient.
Feel free to tell me how I misused WinISD.
I've only ever used it for one other project, a pair of sealed 12" subs.
I know it appears I am turning my back on the Bessel Array - I did model the PC83-4 and 8 and the math/graphs do not seem to work in their favor; cabinet volume, response, etc.
If you can show me where I went wrong with those two drivers I would consider buying 5 to play with.
Tang Band W4-1337sdf
- $79.98
- Spec. 70-20k
- Box 175 Cu.In
- Tuning 82hz
- Port 4" x 5/8" x 8.55"
- -3db 90hz
- Max SPL 100.5db
Dayton Audio DMA80-4
- $18.98
- Response 90-20k
- Box 89 Cu.In.
- Tuning 91hz
- Port 4" x 7/16" x 9.9"
- -3db 87hz
- Max SPL 96.5db
Dayton Audio ND91-4
- $26.98
- Response 65-17k
- Box 89 Cu.In
- Tuning 71hz
- Port 4" x 5/8" x 24.54"
- -3db 70hz
- Max SPL 97.5db
Dayton Audio RS100-4
- $37.98
- Response 80-20k
- Box 200 Cu.In
- Tuning 67hz
- 4" x 3/4" x 14"
- -3db 59hz
- Max SPL 95.5db
i would suggest you consider the off axis response as your primary area of design concern........all 3-4" single driver solutions will be full on beaming everything after 8khz or so.......sit 30 degrees off axis and all vocal intelligability will be lost
You appear to be fixed on bass response.......not sure how you modelled 5 drivers in Win ISD in a Bessel array.........but 5 drivers will have significantly more power handling than 1.......around 3x more as per the Bessel function. Sealed is better here with small drivers and high QTS......ported and the drivers will flap around and smear the bottom octaves.
If you were going to do a single driver per channel solution, the Faital Pro 3fe25 is the way to go......high SPL and efficiency with class leading off axis response.
You appear to be fixed on bass response.......not sure how you modelled 5 drivers in Win ISD in a Bessel array.........but 5 drivers will have significantly more power handling than 1.......around 3x more as per the Bessel function. Sealed is better here with small drivers and high QTS......ported and the drivers will flap around and smear the bottom octaves.
If you were going to do a single driver per channel solution, the Faital Pro 3fe25 is the way to go......high SPL and efficiency with class leading off axis response.
I'm not obsessed with bass response; I have a desire to reach 100hz on the soundbar with a sub covering the rest of the range.
I have been taking drivers I can find and running through WinISD and if they happen to have a relatively flat response to 100hz, they are up for consideration.
That is my criteria.
I did not model 5 drivers in a Bessel array.
I've searched and the only person I can find talking about Bessel arrays is you. I would like to see more on them like REW graphs, or something. So far all I have is you telling me its great. I've never even seen an image of one anywhere, ever.
Care to share photos of what you have been working with?
Care to share measured responses of what you have been working on?
I have been taking drivers I can find and running through WinISD and if they happen to have a relatively flat response to 100hz, they are up for consideration.
That is my criteria.
I did not model 5 drivers in a Bessel array.
I've searched and the only person I can find talking about Bessel arrays is you. I would like to see more on them like REW graphs, or something. So far all I have is you telling me its great. I've never even seen an image of one anywhere, ever.
Care to share photos of what you have been working with?
Care to share measured responses of what you have been working on?
Ultimately, the turbo encabulator seems like a good idea to any idiot who does not know better. In this case, your Bessel Array seems like it might work but I need examples, not just a singular voice on a forum.
How wide did you say the screen was?
Use 2 x 4" full range, one 4" woofer...
Make a square pipe with MDF or foam board, as wide as the screen... divide the screen width by 3, make 3 chambers, and put the full range at nearly the ends.
Make holes for the speakers, square holes are enough, just for the speaker screws.
Make a hole or slot (port) under the woofer, which you put in the center.
A simple 2.1 plate amp, with a big heat sink, can be put inside or outside.
10W per channel is usually too loud in the long term.
Grill, you can choose any material that does not resonate.
That should do, if your room is less than 1500 cubic feet, with reasonable treatment (no sound proofing or soft material on the walls).
There were designs using round tubes, used for bass and side firing speakers, on old 29" CRT TVs, but round is difficult to make yourself.
Use 2 x 4" full range, one 4" woofer...
Make a square pipe with MDF or foam board, as wide as the screen... divide the screen width by 3, make 3 chambers, and put the full range at nearly the ends.
Make holes for the speakers, square holes are enough, just for the speaker screws.
Make a hole or slot (port) under the woofer, which you put in the center.
A simple 2.1 plate amp, with a big heat sink, can be put inside or outside.
10W per channel is usually too loud in the long term.
Grill, you can choose any material that does not resonate.
That should do, if your room is less than 1500 cubic feet, with reasonable treatment (no sound proofing or soft material on the walls).
There were designs using round tubes, used for bass and side firing speakers, on old 29" CRT TVs, but round is difficult to make yourself.
Pipe, I think a 6" to 8" is enough, do block the ends, of course.
You can angle the end drivers outwards if you feel like, it will add to the complexity.
Stuffing etc., that is not my area of expertise.
You can angle the end drivers outwards if you feel like, it will add to the complexity.
Stuffing etc., that is not my area of expertise.
McIntosh is the only commercial offering I’m aware of to use a Bessel array…..they used em for a few years in different designs and it might be what they use in the 10 mid grouping in one of their current towers……they won’t say
I don’t post designs or measurements until complete…….I’ll have something to share in January. I’ve transferred the drivers to a narrow baffle that can be placed in front of a big sheet of plywood, simulating reflections and boundary gain of a large TV. It’s been too cold to do measurements outside though.
I can understand your skepticism.…… but I’m telling you, the typical lobes associated with comb filtering are so narrow and numerous to be completely inaudible. When I first got the drivers, I did a dirty mount in an old Athena Audio slim Tower speaker and laid it on its side……it was bizarre looking at this 4” wide stick speaker yet hearing a 15” point source.
I don’t post designs or measurements until complete…….I’ll have something to share in January. I’ve transferred the drivers to a narrow baffle that can be placed in front of a big sheet of plywood, simulating reflections and boundary gain of a large TV. It’s been too cold to do measurements outside though.
I can understand your skepticism.…… but I’m telling you, the typical lobes associated with comb filtering are so narrow and numerous to be completely inaudible. When I first got the drivers, I did a dirty mount in an old Athena Audio slim Tower speaker and laid it on its side……it was bizarre looking at this 4” wide stick speaker yet hearing a 15” point source.
