Scan speak Revelator 32W4878T00 measurement

scan speak revelator 32w4878 measurement in an infinite baffle

ss 32w4878

32w on infinite baffle

not picture of measurement but you can see how it was installed.

waterfall 32w4878

ss 32w4878

1/6

The Scan Speak 32w4878 is in a weird spot.

Whilst it can handle 20 Hz to 600 Hz quite well, at 30 Hz – 300 Hz is where it performs best.

Most manufacturers, such as Wilson Audio, use a bass reflex alignment at 20 Hz down low and cut it at ~250 Hz

Spoiler, I tend to not like Wilson Audio design.

As a single unit, I can't think of any product on the market that can offer better performance in the 25 Hz – 350 Hz range. NONE

A very solid unit, which I’ve since sold.

Audio Express also tested the 32W 4ohms version:

http://www.audioxpress.com/article/test-bench-scan-speak-32w-4878t00-subwoofer

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Here’s the reasoning of why I sold my pair. And no, I don't regret it at all.

1. It’s fantastic for 30 Hz – 300 Hz, but only up to certain SPL. With a bass reflex or transmission line, you can accomplish 20 Hz flat with this driver. I was using them in an Infinite baffle so 30 Hz was my safer lower end.

2. Laws of Physics always apply, and like any 13" trying to reproduce 20 Hz, it runs out of gas fairly quickly, and has 14mm of linear travel. Mathematics model predicts maximum output to be 104 dB @ 1 meter @ 30Hz, and @ 20Hz, it drops to only 97 dB @ 1 meter. Not enough for my needs. Distortion at such maximum levels is very high too.

3. An 18" driver will easily outperform the 32w4878 in the 15 Hz - 80 Hz range, be much more efficient, won't show any thermal compression, have more output capacity and to boot, have much less distortion. In bass, there is no replacement for displacement.

4. Now having 18" playing up to 80 Hz, the 32w4878’s ability to go down isn’t required, and the design compromise required for the 32w4878 to run at 20 Hz rapidly becomes flawed. (low efficiency, moving mass on the high side to attain a low cone resonance of 18Hz, lower BL to support 14mm of travel, etc.)

5. Finding a 10", 12" or 15" driver that outperforms the 32w4878 in 80 Hz – 600Hz range is very easy*. Most pro and HiFi woofers oriented for such range (not trying to obtain 20 Hertz but limiting themselves to 50 Hz or so) would work much better.

Bottom line:

Better low frequency offered by bigger driver, better mid-bass offered by more suited driver, the 32w4878 tries to do it all, but gets beaten when splitting the range in two, and using two separate drivers for the job.

Of course, it costs more to buy two speakers instead of one, but the benefits of such an approach are considerable. So much so that this is the route I've taken.

I see the 32w4878 like a good pair of "2 - way" speakers. Good but very compromised. I sold my pair to move up to a good 3-way that offers much better overall performance. Can't beat physics. Even the mighty 32W4878 can't.

* of course, any good woofer designed for 80 Hz – 500 Hz (and often able to go up to ~1500 Hz with relative ease) will absolutely be incapable of reproducing 30 Hz, let alone 20 Hz as they aren't designed to go this low. A FaitalPRO 10FE200 would be a very good and affordable candidate for 80-500hz. It is 96 dB efficient, 9 dB more than the Scan Speak! (actually, it’ll go up to 1200 Hz no problem). Lots better drivers are available at higher price points, but one example is plenty for now.