The $52 SB_Acoustics SB29RDC-4 dome tweeter measures similar to the more expensive Satori cloth-dome tweeters, and will blend well with the MW19P midbass. Troels designed his crossover for a stepped baffle, and a flat baffle would have a slightly different crossover circuit.
If your amplifier can handle a 5-ohm load, you can experiment in Xsim with the higher efficiency 4-ohm version of the MW19P-4.
Thanks for the info - Do you like the way they sound? Some of the quotes I read about these stated, "electrostatic" qualities. Is that accurate?
That big bump around 10K does concern me, but I thought I would hear them before deciding if that peak makes them tiring to listen to before trying to flatten it out, or build a passband filter to cross them with another tweeter. If they prove more trouble than their worth, I'll just move on to another tweeter to pair with the MW19.
Question about the software DSP listed on your webpage. I went the Odroid C2 route for music file (FLAC) streaming. Are you aware of an ecasound build for that SMB? I don't really have time to get into software DSP now, but as a future project I am intrigued.
Too late, I already ordered the 8 ohm version of the MW19. I think that should work better with my gainclone or the old Sumo Polaris I have from new.
That SB_Acoustics driver would be a relatively inexpensive route if the AMTPRO doesn't work out. My strategy will be to build the enclosures before the crossovers so that I can get better measurements for the crossover design. I like the idea of a stepped baffle as Troels designed, but I was thinking a spherical enclosure for the AMTPRO-4 might be cool to experiment with.
Big Rounds
I like the "Juke-Box" style for a desktop 2way MW19P-4 + SB29RDC-4.
What do you think about a "Stretched Kii" style for a 2way with your long AMT? Side woofers optional.
A dipole similar to the Hestia V looks like a good fit for the Dayton AMTPRO-4 tweeter, especially with DSP crossovers and equalization to boost 10kHz+ like the Linkwitz LX 521.
New Build: The Hestia V
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Some people won't want to hear this but I think the Satori MW19PNW is better suited to a 3-way than a 2-way. The peak-dip in frequency response and bump in impedance at around 1.5kHz is a cone resonance. If it is anything like other drivers from SEAS and Peerless that have cone resonances around 1kHz then non-linear distortion will also be higher there. On budget drivers is isn't much concern because the non linear distortion from the motor usually swamps it, so you just have to deal with the non-flat frequency response. On a driver like the Satori it should really be crossed below 1kHz if you are chasing world-class performance. Happy to be proven wrong on my theory if anyone has measurement data of the MW19.
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I think I would like to stay with a spherical configuration for this build. I envision it would look something like the Jukebox to house just the Satori high up in the spherical area, then house the AMTPRO-4 in a separate sphere perched on top of the jukebox.
Coming up with that spherical shape is going to be a challenge. One option would be to create the AMTPRO sphere using fiberglass with internal wood bracing. The bass cab could be a traditional MDF cabinet with an added stack of MDF on top that is machined to the final spherical shape. Or I could try to vacuum bag birch ply into a spherical shape and mate that to the rest of the cabinet somehow. Perhaps machined aluminum could be used, but that might cost a small fortune.
I am tempted to try using a minidsp to provide flexibility to experiment with different crossover configurations. That and a couple of inexpensive chip amps from Parts Express.
I haven't measured this exact driver, but I have measured the MR13P-4, another Satori driver (5" nominal diameter). I did this while suspending the driver in free air about 2m above the ground in a large room with high ceilings. I could get about 50Hz resolution this way, and was testing for open baffle use. I measured several angles in the horizontal plane, both to the front and rear. I found a narrow resonance at 1.5kHz that showed up in the frequency response differently to the front and rear and produced a big spike in the 3rd order harmonic distortion. I did not measure IMD at this frequency so I am not sure about how that would be affected, but it probably is (that's my guess at least). For the price of the MR13P-4 and hype about the Satori line I was not all that impressed by what I found.
I am attaching some data that you might find interesting. After testing I sold off my pair and went with another driver that did not have the FR irregularities I found, which would probably be hidden if the measurement had lower resolution...
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I've been using this combination for the better part of two years as my main system, crossed with a miniDSP.
I've tried everything from 1100-2400hz, and variations of slopes. I ended up slightly asymmetrical, with a 1700 woofer LR4 and a 1750 tweeter LR4, or somewhere close to there.
I can go into detail if you have any specific questions, or if you'd like me to take measurements of any specific crossover on the miniDSP I would be happy to oblige.
Pic below:
IMG_20170518_144439.jpg - Google Drive
I've tried everything from 1100-2400hz, and variations of slopes. I ended up slightly asymmetrical, with a 1700 woofer LR4 and a 1750 tweeter LR4, or somewhere close to there.
I can go into detail if you have any specific questions, or if you'd like me to take measurements of any specific crossover on the miniDSP I would be happy to oblige.
Pic below:
IMG_20170518_144439.jpg - Google Drive
Those look nice! I am torn between building a crossover and using a miniDSP. My gut says measure and build a crossover. 1700 does seem to be an area where both drivers would perform, do you like the way they sound? Also, did you try it in a dipole configuration?
My Satori's arrived yesterday, so I will likely have more questions as I get into my build.
The Satori's arrived yesterday, so I am anxious to start building. I'm afraid the process is going to be drawn out though due to competing priorities.
I did start planning my direction today. I'm thinking of going with 10" Schedule 80 PVC pipe for the core of the enclosures. I have already worked with PVC with my current speakers, which are PVC quarter-wave pipes. These would follow the same theme, but would be bass reflex.
I think I might try using the AMTPRO in a dipole configuration. It would be much easier to deal with physically, though I'm not sure if doing so would add to the complexity of the crossover. Time to read up on the trials and tribulations of dipoles.
I did start planning my direction today. I'm thinking of going with 10" Schedule 80 PVC pipe for the core of the enclosures. I have already worked with PVC with my current speakers, which are PVC quarter-wave pipes. These would follow the same theme, but would be bass reflex.
I think I might try using the AMTPRO in a dipole configuration. It would be much easier to deal with physically, though I'm not sure if doing so would add to the complexity of the crossover. Time to read up on the trials and tribulations of dipoles.
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The AMTPRO-4 SPL curve and polar pattern look challenging to get great sound. If you have an old wood cabinet you might want to knock-out a test design and search for AMTPRO love before you invest in a complicated-$$ construction.
itschris, Excellent construction work on your 2-way cabinet.
How much miniDSP equalization did you use on the AMTPRO-4?
To your ears, how does the AMTPRO-4 compare to a good dome tweeter?
A tall Kii cabinet still looks good
itschris, Excellent construction work on your 2-way cabinet.
How much miniDSP equalization did you use on the AMTPRO-4?
To your ears, how does the AMTPRO-4 compare to a good dome tweeter?
A tall Kii cabinet still looks good
I had a heck of a time trying to get a decent sounding crossover when I tried them as a dipole. At that point I was still trying to work things out passively, so maybe I would have done better with the miniDSP. 1700-1750 was chosen because of the best polar response match, and the crossover offset was done for phase alignment. I'm very happy with them here and haven't had the urge to go back and tweak anything.
It should be noted I'm not very experienced with passive crossovers and have only built a couple pairs I'm really proud of. You might have a better chance than I did
The AMTPRO-4 SPL curve and polar pattern look challenging to get great sound. If you have an old wood cabinet you might want to knock-out a test design and search for AMTPRO love before you invest in a complicated-$$ construction.
itschris, Excellent construction work on your 2-way cabinet.
How much miniDSP equalization did you use on the AMTPRO-4?
To your ears, how does the AMTPRO-4 compare to a good dome tweeter?
Thanks
It was constructed inside a college dorm room with hand tools & the PE knock-downs. I don't have extensive experience with other drivers, but I do regularly listen to the YG Acoustics Hailey 1.2s; I think the AMTs are definitely no slouch, and the quality is in a realm that's different strokes for different folks. They definitely keep pace with the Satori's. I think they're a good step above the RS28A, but my experience is limited beyond that. If I were to go back to the beginning, I don't think I'd change a thing in driver choice. I'm hesitant to give subjective comparisons, but I do think the 3k region is a little heavier/fuller than the Hailey's. The limited vertical dispersion is definitely a plus for me.
WRT equalization, I think it's rather a lot (6db+) and even more near the ~10k peak. As you noted, the SPL curve was challenging; at the crossover point, the AMTs are pretty inefficient and I don't believe there is any attenuation. The polars (non-dipole) looked pretty well behaved to me when I was working on them.
Another interesting point was that in my final measurements I didn't notice much of a drop-off in the top octave. I'm not sure if its because the 3-13k range gets cut so much, or some other factor. At some point I'd like to remeasure without any crossover because I can't find my original files anywhere.
Lastly, the dipole CSD of the AMT wasn't quite as great as when I closed off the back. Unfortunately I never took the time to investigate.
I too found the AMTPRO to lack a bit up top, so what better way to compliment an AMT than with another AMT. I used the little AMTMini from PE. This was done in my 442 speakers, found here:
http://s1151.photobucket.com/user/6thplanet/library/Project 442?sort=6&page=2
I crossed it kinda low in the 1K range and never really had any issues. Those took second place at one of PE's annual MWAF gatherings, so yeah, they sound quite nice!
http://s1151.photobucket.com/user/6thplanet/library/Project 442?sort=6&page=2
I crossed it kinda low in the 1K range and never really had any issues. Those took second place at one of PE's annual MWAF gatherings, so yeah, they sound quite nice!
Hi Linesource,
Are you maybe aware of any good design combining MW19P (black version) with Satori tweeter? Other than Troels design, I couldn't find anything.
Do a google search for satorique - Lots of interesting German variations on these drivers