Hey There!
I just purchased a couple of AMTPRO-4s on sale from Parts Express and I'm looking for drivers to pair them with. My thought is a two-way with the Satori MW19PNW to keep it simple. Crossover would be an LR2@1500hz on both the low pass and hi pass.
Would this be a good pairing? Is 1500hz too low? Too high? The MW19PNW dips about 2db around 1200hz. Does that rule out this pair? Or, would I need a different x-over point, or can I work with the dip electrically to smooth it out?
Thanks in advance
I just purchased a couple of AMTPRO-4s on sale from Parts Express and I'm looking for drivers to pair them with. My thought is a two-way with the Satori MW19PNW to keep it simple. Crossover would be an LR2@1500hz on both the low pass and hi pass.
Would this be a good pairing? Is 1500hz too low? Too high? The MW19PNW dips about 2db around 1200hz. Does that rule out this pair? Or, would I need a different x-over point, or can I work with the dip electrically to smooth it out?
Thanks in advance
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It does look like that from the FRD/ZMA files Parts Express provides for the AMTPRO-4. Comments on their website indicate that these are being used down to 1500hz, although further comments do suggest 2K-2.5K.
So, if I had to set my x-over point to 2K-2.5K, would you think this Satori driver could handle it, or is there a different 8" high-end-ish driver you know is capable of being crossed at those points?
And how does this dayton sound like a midrange or like a twitter spooky?
Can you record the sound to hear how it sounds?
I also look at him.
Hi, the satori is good for it even though it may need a little more complicated filter as the simulatation illustrates.
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I appreciate your help. I think then I will take a chance on that driver. I will use OmniMic and DATS to measure the drivers before building anything, however how did you do your simulation? Do you happen to have FRD/ZMA files for that Satori to share?
The Satori is great upwards. Try to find if there is a frequency where both drivers have the same dispersion pattern at 30 and 60 deg. Above 2k.
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You can have these traced from a spec sheet and assumed on a baffle 22x45 cm. Vented box tuned to manufacturer's suggestion.
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Thanks for that link. I ran across a similar design on the Part-Express forums here: Bamboozled - Techtalk Speaker Building, Audio, Video Discussion Forum.
This is great, thank you!!
Would you mind elaborating on the process used to trace from a spec sheet? How is the baffle size and vented box tune used when deriving data from the spec sheet?
Ah, found the way to derive those files from screenshots of the response graphs.... I found SPL Copy app here:
SPLCopy.zip - Google Drive
Expert designer Troels Gavesen built the MW19 Studio Monitor using the MW19P-8 and selected an LR4 circuit at 1700Hz for the crossover.
"The MW19P-8 midbass driver used here is a rather large driver having a radiating area of 158 cm^2, a little bigger than the ScanSpeak 18WU drivers. Due to size of the midbass we need a low point of crossover to the tweeter ... Here we go with a point of crossover at 1700 Hz providing the best possible frequency response and we use an LR4 filter (circuit) providing some added presence in upper mid/lower treble despite the large cone area of the midbass. By using a steep filter we reduce the "echo" of the midbass beaming. "
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I use passive LR4/LR4 cricuits at 1650Hz with the MW19P-4 midbass and SB29RDC-04 dome for TV/desk speakers.
"The MW19P-8 midbass driver used here is a rather large driver having a radiating area of 158 cm^2, a little bigger than the ScanSpeak 18WU drivers. Due to size of the midbass we need a low point of crossover to the tweeter ... Here we go with a point of crossover at 1700 Hz providing the best possible frequency response and we use an LR4 filter (circuit) providing some added presence in upper mid/lower treble despite the large cone area of the midbass. By using a steep filter we reduce the "echo" of the midbass beaming. "
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I use passive LR4/LR4 cricuits at 1650Hz with the MW19P-4 midbass and SB29RDC-04 dome for TV/desk speakers.
The AMTPRO-4 frequency response makes it less than ideal about 10kHz. I attached a measurement I took on a unit that I own, in free air. It might be possible to EQ the response so that you get a smooth transition between the mid-passband level of (on my plot) 105dB and the near 10kHz response level of 100dB - you might want to EQ out the "hump" around 10kHz or it could sound fatiguing. I would probably try this approach with an active DSP crossover, however, because you might need to combine several EQ bands to get it right.
The AMPPRO-4 also has a rather "tall" diaphragm for a tweeter. The size of the diaphragm is especially a problem in the vertical plane, where the response pattern starts to narrow starting at 4kHz. You can use it as low as 1.5-1.8kHz (it will need a back enclosure). If you add a small dome tweeter (e.g. Ox20?) crossed over at 5-7kHz you will get better overall performance from 5kHz to 20kHz.
On the plus side, the distortion signature is pretty clean and efficiency is high. It's a good driver when used in a way that minimizes some of the response issues.
Note: If you have advanced hearing loss you might not notice the issues above 5kHz I mentioned since these are getting near the edge of your ability.
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Agreed! I always use something above the AMTPRO-4 even when eqed flat. Seems like it is missing that something over extended listens.
Thanks for finding this, I checked out the build on Troels Gavesen's website. If the AMTPRO-4 doesn't work out, I may end up with a Satori tweeter instead. Too bad the component values of the crossover aren't listed.