Audax PR170MO
I'm gonna vote for the PR170MO (it's letter 'O' and not zero at the end) not because of some 'ultimate' sound quality this or that. Rather, I have 4 of them (and 4 slightly damaged ones) and I don't have time or skills to make a properly implemented system with them. So I'll just ride on your coat tails!
I take it this is a 3-way?
Key question: Is this for home or pro use? If it's a living room speaker then the PR170 can be used much lower with less steep filters.
Here are two thread with some great info:
http://www.diyaudio.com/forums/multi-way/77784-audax-pr170m0-100-db-just-94-db.html
http://www.diyaudio.com/forums/multi-way/232794-pa-midrange-hifi-3way.html
They are only a few pages long so it's easy to browse them.
Here are some quotes from the first thread:
"The PR170M0 is meant to be operated significantly above it's fundamental resonance. There the SPL is determined by many factors other than T/S Parameters. That said, I make it 97db/2.83V/1m and not 100db. Still much depends upon use as well."
"I've worked extensively with PR170M0s and variants (PR17HR70, PR17HR100).
I too, would limit low end extension to no lower than 400 Hz, 18 dB/oct, or 500 Hz, 12 dB/oct. IME, for a more "public address" application (which is where these drivers see their most usage, ie, in several EAW and Peavey high-end cabinets... Audax OEM supplied the PR17 to these manufacturers, among others), a range of 500-5000 Hz is QUITE usable... I tend to use these drivers in a small enclosure (Qtc of about .8 to 1.0), with a silght overlap between the woofer and midrange, and a slight "underlap" (gap) between the midrange and tweeter. Also, using a slightly lower-Q low-pass (ie, larger inductor and smaller cap) on the top end of the PR170, will also benefit the response greatly. For the most part, if you use the tricks specified, the response will wind up pretty much ruler-flat. .. the "rising response" will be very well compensated for. Exemplary dynamic range and control...
For a "hi-fi" application, using them in the range of about 400-3200 Hz (three octave spread) would be quite nice. Avoids most of the breakup, and what you do get, does not color the sound to any detectable amount. GREAT driver. My first choice for high-efficiency 3-way systems, even to this day..."
"Yep, first breakup on a 6" driver is usually around 1600 Hz or so. But, from the data I've collected using this driver, the breakup is very benign... and doesn't really begin to color the sound, until well above 3KHz. In fact, even using it up to 5KHz... the dispersion is more of a sonic factor (ie beaming) than breakup... to a LARGE margin..."
Here are some quotes from the second thread:
"I use the audax pr170 crossed around 350hz and 5khz. The sound is sublime. efficiency is 100db. its a incredible driver. It is the best mid I have ever heard.
I use the beyma 12br70 for my bass need, and the two blend seemlessly.
look around for what people think of the audax, thorsten loesch for example, which is a reference in audio thinks highly of this driver..."
Here's a ton of info on the PR170MO
View attachment AUDAX-Vergleichsliste-2009-09.pdf
I warned you it was a ton!
Oh and if you don't have a DSP crossover you simply must get one! I have a miniDSP 2x4.
Here's my thread on these incredible speaker designing tools!
http://www.diyaudio.com/forums/mult...-tool-real-time-dsp-crossover-adjustment.html
"High level of flexibility: correct open baffle, notch resonances, correct driver response, xover point, slopes (BW6-24, LR12-48, Bessel ..), delay, attenuation ...
The 2 way plugin interface starts with digital atten, then 6 filters of pre eq, then crossovers, then 6 more filters of eq, then atten and delay. Whew!!!
Awesome! Doing this analog would take forever (passive), awhile (active), or a bit (Pass/Marchant variable xover) but with DSP it's click click click ... go!"
...
"Oh yeah, it also has a digital (24bit) vol control ($5 pot) so you can use the top part of volume knob without touching the actual 16bit CD resolution! !! !
Next I'm going to try 3 and 4 way by getting the 4-way plugin for an extra $10. With it the 2x4 can be easily reprogrammed to become a 1x4 (1 in and 4 out). !!! !!!! !! This of course means it's not stereo anymore but that's ok for testing for now.
Then I'll get another 2x4 so I'll have a stereo 3/4 way and then go full digital with the $70 miniDigi (2 coax and 2 optical SPDIF ins that connect directly to one or two 2x4s)!!! !! "
Good luck and I hope you choose the PR1790MO. Keep us posted (so I can copy your design

)
Cheers,
Jeff