Sometimes you can also let subjective feelings decide
Like I said before, I think you can make a very great sounding speakers with any of those speakers.
So that could be a fair reason.
For my own DIY projects, I try to just either go for a nice "theme" for a certain speaker, or let the choice be decided what I can get 2nd hand. This prevents you from going into never ending loopholes.
I think the Dayton is a more sexy looking speaker as well.
Although in a bit more "vintage themed" style speaker I would go for the SB instead if the budget allows it.
How about flat membrane Tectonic BMR drivers? Only around 30$
https://www.tectonicaudiolabs.com/audio-components/bmr-speakers/
https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr_v2/
https://www.tectonicaudiolabs.com/audio-components/bmr-speakers/
https://www.erinsaudiocorner.com/loudspeakers/philharmonic_bmr_v2/
Here is the VituixCad simulation of using an idealized 5 inch mid driver. It is slightly different than the 4 inch driver which I showed in post #135. The DI curve is more linear.
This is an ideal piston representation of a 10 inch woofer, a 5 inch mid driver, and an ABEC simulation of an SB26 in an Augerpro waveguide 127mm wide 78.5mm high.
This is an ideal piston representation of a 10 inch woofer, a 5 inch mid driver, and an ABEC simulation of an SB26 in an Augerpro waveguide 127mm wide 78.5mm high.
Interesting drivers... It reminds me of the woofers used in the phase technology PC60 and PC80 speakers.
j.
Yah. And unfortunately the proven performers don’t come in circular frames.
https://www.parts-express.com/Tectonic-TEBM46C20N-4B-BMR-3-Full-Range-Speaker-4-297-2157?quantity=1
https://www.parts-express.com/Tecto...Full-Range-Speaker-8-Ohms-297-2176?quantity=1
https://www.parts-express.com/Tectonic-TEBM46C20N-4B-BMR-3-Full-Range-Speaker-4-297-2157?quantity=1
https://www.parts-express.com/Tecto...Full-Range-Speaker-8-Ohms-297-2176?quantity=1
I should have added that as a written requirement in post#1: Drivers must have circular frame that can be recessed.
I might make an exception for an elliptical waveguide, but I am not going to use any driver that requires rear mounting, or has a truncated or polygonal frame. It is not a written requirement, but it is nonetheless a requirement.
I might make an exception for an elliptical waveguide, but I am not going to use any driver that requires rear mounting, or has a truncated or polygonal frame. It is not a written requirement, but it is nonetheless a requirement.
Ben,
So that rules in the PC83 and PC105.
That rules out the BMR then.
What about something like the DMA series?
https://www.parts-express.com/pedocs/specs/295-591--dayton-audio-dma105-8-specification-sheet.pdf
Or-
https://www.parts-express.com/pedocs/specs/294-1124-faitalpro-4fe35-8-specifications.pdf
(Again I have no direct experience with it)
Does these need recessing? (I hope not- I have the new 4FE42 (neo version, copper cap) on order…)
It probably depends in the frequency region of interest? ~3KHz seems to frequency wavelength (11.4mm) where diffraction can occur due to thickness of the frame the distance from the dome/cone to an edge.
http://zaphaudio.com/mtg-surface.html
OT: Can sometime please remind me of the math between sound wavelength and diffraction/interference at edges or regions of acoustic discontinuity, for lack of my better term?
So that rules in the PC83 and PC105.
That rules out the BMR then.
What about something like the DMA series?
https://www.parts-express.com/pedocs/specs/295-591--dayton-audio-dma105-8-specification-sheet.pdf
Or-
https://www.parts-express.com/pedocs/specs/294-1124-faitalpro-4fe35-8-specifications.pdf
(Again I have no direct experience with it)
Does these need recessing? (I hope not- I have the new 4FE42 (neo version, copper cap) on order…)
It probably depends in the frequency region of interest? ~3KHz seems to frequency wavelength (11.4mm) where diffraction can occur due to thickness of the frame the distance from the dome/cone to an edge.
http://zaphaudio.com/mtg-surface.html
OT: Can sometime please remind me of the math between sound wavelength and diffraction/interference at edges or regions of acoustic discontinuity, for lack of my better term?
Last edited:
I did a quick survey of my friends and acquaintances who might build a copy of this speaker. There was a lack of enthusiasm for using a router guide bushing to route an elliptical recess. Much more enthusiasm for making a tapered bevel...
That is fine. I have spent a lot of time in the last year with a high quality waveguide system, as well as a high quality non-waveguide system. They are different, but I can't say one is better than the other. On any given work of music, yes there is one or the other that I prefer, but overall, no. I enjoy both, they are different, but equal...
That is fine. I have spent a lot of time in the last year with a high quality waveguide system, as well as a high quality non-waveguide system. They are different, but I can't say one is better than the other. On any given work of music, yes there is one or the other that I prefer, but overall, no. I enjoy both, they are different, but equal...
It depends on the distance from the source and the size of the discontinuity. I think that exact solutions (i.e. double integration) gets complicated fast, so simulation is our best friend... As a practical matter, I found that a discontinuity as small as 1/10 wavelength has a measurable effect.
The exact math? I would ask @vineethkumar01 or @tmuikku or @fluid... I am too long away from university for that...
This is a reasonable rule of thumb. Real problems are where the reflection distance is a quarter wavelength causing an overall half wavelength path delta.
Midrange with surface-mounted steel frame should not be a problem, it has cone surround anyway. But square frame is not pretty...
DMA-105 has thick cast frame, not pretty on a 3-way either but nice perfomance
https://www.parts-express.com/Dayto...ne-Full-Range-Driver-4-Ohm-295-590?quantity=1
Another way to make a recess is to make an add-on thin mask to the baffle. Or cover the baffle with cloth!
DMA-105 has thick cast frame, not pretty on a 3-way either but nice perfomance
https://www.parts-express.com/Dayto...ne-Full-Range-Driver-4-Ohm-295-590?quantity=1
Another way to make a recess is to make an add-on thin mask to the baffle. Or cover the baffle with cloth!
Last edited:
Yeah about tenth of wavelength, perhaps less if discontinuity is equidistant from the source like mounting rim of a driver, where amplitude is strong (short additional path length) and accumulates on-axis as it's equidistant. In general, physical size and shape show strong effect on acoustic measurement when they are about wavelength in size. Picture baffle step for example, huge hump around 1wl and has long tail towards lows and could be said there is about none at 10x the wavelength. There could be comb above until beaming is strong enough, or roundovers big enough.
In general, the immediate acoustic environment of the transducers makes most effect. What I mean is that the point where you first lose the game for some particular wavelength makes most interference and anything that happens after has less effect simply because the amplitude drops with distance, also part of the energy was already distributed on the first discontinuity. Some diffraction happens on all features all around your box/structure, on various wavelengths, but the effect just tapers of past the first one.
In general, the immediate acoustic environment of the transducers makes most effect. What I mean is that the point where you first lose the game for some particular wavelength makes most interference and anything that happens after has less effect simply because the amplitude drops with distance, also part of the energy was already distributed on the first discontinuity. Some diffraction happens on all features all around your box/structure, on various wavelengths, but the effect just tapers of past the first one.
If you can get Sigma Studio, ALLO Piano might do it.
For utter cheaps, CMedia CM6206 based sound card, RPi3 onwards, Charlie Laub's LADSPA IIR crossover and filter set and 4-6 TPA3118 "mono" class D amps. Power with ASUS 19V laptop bricks. Though troubleshooting can be "awful" if you're not computer literate and determined or bloody-minded.
Thank you.
Well i would like no troubleshooting neither have to turn me into a computer geek to have just acceptable sound quality.
I hoped something like Camilla dsp software and 'paint by number' solution for dacs... i'm too optimistic!
I will still use my fancy loudspeaker management unit for some times it seems ( after all it wasn't a bad investissment even if costly at time of purchase with more than 10years of constant use without upgrade).
Well i would like no troubleshooting neither have to turn me into a computer geek to have just acceptable sound quality.
I hoped something like Camilla dsp software and 'paint by number' solution for dacs... i'm too optimistic!
I will still use my fancy loudspeaker management unit for some times it seems ( after all it wasn't a bad investissment even if costly at time of purchase with more than 10years of constant use without upgrade).
Sorry, I totally missed this post.
It's definitely possible, also working on a couple of ideas.
People are happy to join in if they want