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Purifi PTT6.5W04-01A 6.5" midwoofer

McFly

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Nice sensitivity! However IMO while not a true midrange in the traditional sense, it looks like the breakup is starting after 3khz and I wouldn't cross it any higher than 2-2.5khz, where you'd still need a waveguide of some sort if directivity matching with your HF driver was your goal. Distortion specs look extraordinary between 100hz and 2khz. ATC mid dome levels. Couple 8" (sub)woofers crossed 100-150hz to this driver with a waveguided tweeter could make on hell of a floorstander.

If they bring out a midrange 4" with similar performance, we could be looking at the new possible leader in the traditional "midrange" band (300hz to 3-4khz)
 

tktran303

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Well there’s a lot of ways to skin a cat.

Some would say that wouldn’t use a midrange smaller than 5 inches.

A pair of 12–15” woofers goes well with a 6.5” midrange crossed to a waveguided compression driver…
 

AnalogSteph

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I'm a bit surprised that such a major change in fs (from 33 to 52 Hz) hasn't resulted in a greater increase in sensitivity - the voice coil may have been put on a diet for the better highs extension seen? (Compared to a traditional high sensitivity wideband driver like a Visaton BG17, that one adds about another 3 dB to efficiency but needs fs of over 100 Hz to pull that off, with a response that is substantially more lumpy though still more extended on top. The 6.5M04 looks exceptionally flat from 200 Hz up to about 3 kHz.) I always thought fs should have a major effect on efficiency as it appears cubed. Looks like the factor that actually matters is (Bl/Mms)².

In any case this driver should be more BR-friendly in its parameters. It's still very much a midwoofer that can easily be crossed over at 150-ish Hz, so that's neat.
 

briskly

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I'm a bit surprised that such a major change in fs (from 33 to 52 Hz) hasn't resulted in a greater increase in sensitivity
Stiffness has nothing to do with efficiency in the mass-controlled region well above Fs. In the passband expression, the stiffness terms in Qes^-1, Vas, and Fs^3 cancel out. It remains in the damping-controlled region and below.
 
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