You are right X, on looking back at that 7khz peak, I don't think it is the room. I will have an experiment.
Regarding bass distortion, that is without a front baffle gasket, or stuffing. I need to go buy some rockwool
Regarding bass distortion, that is without a front baffle gasket, or stuffing. I need to go buy some rockwool
This looks great! Congrats and well done!
I'll have to do some thinking/CADing to figure out if these are a possible match for my home...
First: Appearance.
This is how my media console looks like:
I would put them atop of that. I feel like the design is hard to make slim (width) as you need to be able to fit a quite large COTS WG, so why not make it just that: Wide and low. Maybe something like this:
Sketches (Width: 480 mm/18.9", height: 330 mm/13", depth: 320 mm/12.6"):
Top and bottom are either high gloss white/black or solid oak. Front/sides/back is covered by one piece of fabric, maybe something like this:
Should be fairly easy to make. Inside: a XT1464 coupled to a SB65, I like the constant directivity aproach more than the tractrix kind. I would however not make it sealed, but have about 1 Sd of holes on each side to reach cardiod/supercardiod behavior.
They need to be aimed slightly up as the console is quite low. I'll need to try a few kinds of short legs.
Now to my question: I have 4 of the Faital Pro 8FE200-8, would these work? X: care to sim them in akabak? I don't need to go very low as the media console contains one subwoofer in each end.
/Anton
I'll have to do some thinking/CADing to figure out if these are a possible match for my home...
First: Appearance.
This is how my media console looks like:
I would put them atop of that. I feel like the design is hard to make slim (width) as you need to be able to fit a quite large COTS WG, so why not make it just that: Wide and low. Maybe something like this:
Sketches (Width: 480 mm/18.9", height: 330 mm/13", depth: 320 mm/12.6"):
Top and bottom are either high gloss white/black or solid oak. Front/sides/back is covered by one piece of fabric, maybe something like this:
An externally hosted image should be here but it was not working when we last tested it.
Should be fairly easy to make. Inside: a XT1464 coupled to a SB65, I like the constant directivity aproach more than the tractrix kind. I would however not make it sealed, but have about 1 Sd of holes on each side to reach cardiod/supercardiod behavior.
They need to be aimed slightly up as the console is quite low. I'll need to try a few kinds of short legs.
Now to my question: I have 4 of the Faital Pro 8FE200-8, would these work? X: care to sim them in akabak? I don't need to go very low as the media console contains one subwoofer in each end.
/Anton
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x - thanks for the gated vs fdw comparison. For myself I prefer the gated, unsmoothed version to see exactly what's going on. Lots of detail lost with the fdw, though it would be nice to see the fdw with no smoothing, as well as a comparison of the polar data set.
Thanks what a beautiful journey, regarding measurements would you like to share W/T impedance plots too.
Seems in sealed to hit a Q 0,7 that one SB23NRXS45-8 wants 38,19 liter, so probably not bad you ended up 40 liters for the duo. Below is response difference for initial plan that was 2x8 liters verse final 40 liters.
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This shape should work as well, not very easy to make though...
/Anton
An externally hosted image should be here but it was not working when we last tested it.
/Anton
Thanks Byrtt - love the building montage!
I will probably have to remeasure the impedance plots as I didn't save them.
Will dig the kit out this weekend.
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Nate - I am using a different horn to X, but here is my unsmoothed data for what it is worth! Measurements done in non-ideal setup obviously...
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Onni,
Nice concepts. If you look at the aspect ratio of my horn, with enclosure and in horiz orientation it can probably work for your shelf. 17in wide x 11in high x 13in deep. I never thought of grille cloth. But I imagine if you covered this compact horn with grille cloth it would look like an ordinary speaker with performance that astounds and surprises people.
Imagine a box tightly conforming around this:
Top view if horizontal orientation:
Seems to be a good choice for this aesthetic:
Nice concepts. If you look at the aspect ratio of my horn, with enclosure and in horiz orientation it can probably work for your shelf. 17in wide x 11in high x 13in deep. I never thought of grille cloth. But I imagine if you covered this compact horn with grille cloth it would look like an ordinary speaker with performance that astounds and surprises people.
Imagine a box tightly conforming around this:
Top view if horizontal orientation:
Seems to be a good choice for this aesthetic:
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Exactly my thought! I showed my wife a few horns and apparently they don't have a place in our home 😉 But if covered with some kind of fabric it should be fine 🙂Onni,
Nice concepts. If you look at the aspect ratio of my horn, with enclosure and in horiz orientation it can probably work for your shelf. 17in wide x 11in high x 13in deep. I never thought of grille cloth. But I imagine if you covered this compact horn with grille cloth it would look like an ordinary speaker with performance that astounds and surprises people.
Imagine a box tightly conforming around this:
Top view if horizontal orientation:
Seems to be a good choice for this aesthetic:
/Anton
Anton - go for it - these things sound amazing!
Here is my new 100dB distortion with sorbothane gasket on baffle - improved the HD even more.
The box still needs stuffing which may improve things further...
PS - Xrk - I think you were right about the SB65 - I loosened off the screw a little and HD improved a lot - just over-tightened things I think.
Here is my new 100dB distortion with sorbothane gasket on baffle - improved the HD even more.
The box still needs stuffing which may improve things further...
PS - Xrk - I think you were right about the SB65 - I loosened off the screw a little and HD improved a lot - just over-tightened things I think.
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Lot of cool details and work sorted out in building montage.
No hurry with impedance plots take your time, can see below you have plenty of tasks and ideas to squeeze last bits of quality.
100dB at 1 meter and you are getting better than -40dB HD at 30Hz! Amazing - no sub needed, really. 😀
Glad that my suspicion of a distorted frame on the SB65 was the source of the high HD at 2k-7k! 🙂
That 7k peak went down to -55dB!
But now there is the -45dB peak at 5.5k - still not a bad at all.
This speaker's HD performance is actually, very far beyond what I would have expected. With the rock wool,it will maybe hit -45dB at 30Hz? For a speaker to have a range from 30Hz to 20kHz with a two way sealed, quasi transient perfect, near flat phase, low HD, is excellent.
Actually, what is the -3dB and -6dB point for the bass? What is the voltage drive level required to get 100dB at 30Hz? Can you show a measured electro-acoustic XO plot like this one (upper right graph) you did earlier?
Well done!
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It would great if anyone willing to could measure the speakers exactly as described here
http://gedlee.azurewebsites.net/downloads/On Measureing loudspeakers.pdf
And then send the measurement files to Dr. Geddes. He will then process them and upload high resolution polar maps into his polar map database on his website. Where they can be compared to Gedlee's woofer/waveguide combos as well as Nate Hansen's successful EOS Synergy, among others.
GedLee LLC
It's really an excellent offer on his part and a great opportunity to see definitively what the polar response is of the Synergy designs in this thread.
-Shawn
http://gedlee.azurewebsites.net/downloads/On Measureing loudspeakers.pdf
And then send the measurement files to Dr. Geddes. He will then process them and upload high resolution polar maps into his polar map database on his website. Where they can be compared to Gedlee's woofer/waveguide combos as well as Nate Hansen's successful EOS Synergy, among others.
GedLee LLC
It's really an excellent offer on his part and a great opportunity to see definitively what the polar response is of the Synergy designs in this thread.
-Shawn
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These waveguides are different than a SEOS, which aim for a flat DI over as wide a range as possible. So you are not going to do any better than the factory pristine (undrilled) waveguide. Fortunately, both 18Sound and Faital Prog provide the polar DI maps for their waveguides used by Bushemeister and myself, respectively.
18Sound XT1464 (elliptical):
Faital Pro LTH142 (tractrix):
vs. Gedlee Summa:
An externally hosted image should be here but it was not working when we last tested it.
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100dB at 1 meter and you are getting better than -40dB HD at 30Hz! Amazing - no sub needed, really. 😀
Actually, what is the -3dB and -6dB point for the bass? What is the voltage drive level required to get 100dB at 30Hz? Can you show a measured electro-acoustic XO plot like this one (upper right graph) you did earlier?
Well done!
Here you go X:
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Would it not still be worthwhile to have a high resolution polar map of the completed speakers in the database? For science!
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I'd say this project is moving past the pilot phase in a hurry 🙂. Time to go for a stereo pair! Of course I remain curious what a little FIR filtering might bring here. The results so far look excellent though. It's fun to see a world wide collaboration at work, all projects should work like this! (lol)
Not exactly bookshelf size speakers anymore.........although still excellent work as what may be the smallest Synergy type system to date.
On another note, just found that 1/8" felt lining portions of the interior walls on the TC9/Maltese horn made a very large reduction in HF ripple- from +/-4 dB, to near that of a compression driver, around +/- 1dB, with only about one dB loss of sensitivity. Also made polar response more uniform.
Unfortunately, the "very large reduction in HF ripple" must have been an interpretation error (probably comparing two different measurement angles) after spending this morning trying damping felt in various places in the horns, I could not replicate the "last test of the day" results from yesterday.
The sensitivity loss turned out to be too much for the very minor improvement in polar response in some frequency ranges, and the polar response was worse in others, and overall no smoother.
Although the quad array of narrow dispersion Maltese horns using TC9s will work well for my intended use (center fill for high SPL live sound reinforcement) the polar response is not nearly as good as a single horn of similar dispersion pattern.
The tape and cardboard TC9FD-18-08 45 x 30 conical horn prototype whipped up in about 20 minutes just before last Christmas had really good polars, and a only a few easy to correct "bumps", raw response below.
Note that only about 6 dB of EQ correction would be required to flatten response from 250 to 16kHz.
Though the initial conical horn flare is 45 degrees, actual horizontal coverage is 60 degrees (-6dB 30 degrees off axis) with uniform constant directivity pattern control to 650 Hz.
It would be easy to build from plywood (or foam core), and much easier to mount woofers on than elliptically shaped horns.
Art
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