Need midbass 150mm-170mm 80-2kHz

[ro9397]

Cost is an issue: eight mid-bass per LCR channel = twenty-four mid bass per system. We're building two identical systems (myself and a friend) requiring forty-eight mid bass pieces (fifty pieces with two spares).

Please state whether you heard or did not hear the suggested driver (most interested in the former).

Sound quality requirement: lively, dynamic...no stereotypical soft audiophile presentation.

Size: 150mm to 170mm (5.9" to 6.7")
>170mm exceeds practical baffle dimensions
<150mm clashes cosmetically with large wave guide

Range: 80 Hz to 2 kHz
One FR bump is OK
One big FR dip is fail

Crossovers:
Active HP 2nd order @ 80 Hz
Passive LP 4th order @ 2.0 kHz

Ported or sealed
86 dB+ anechoic
8 Ohms preferred, consider 4 or 16 Ohms
50Wrms+ with active HP 2nd order @ 80 Hz
Frame: prefer cast for cosmetics but we presume stamped can meet strength requirements in this size range

Diaphragm material: consider any. No absolute conclusions, but a promising poly-cone SBC 6.5" lacked dynamic liveliness. Also, every carbon fiber mid bass I've heard (dozens) lack transient snap and macro dynamics (not necessarily the case with bass-only drivers).

A promising Faital paper/ferrite 5.25" failed because of an audible dip that does not appear on its FR graph.

Thanks for your effort!

 

[ScottG]

IF you are disappointed with the dynamics of virtually any driver, then you may well be disappointed with any substantial array - no matter how dynamic-sounding each individual driver is.

That "dynamic" sound is often a function of excursion under normal operation (..and includes force/mass/sensitivity etc..). Large arrays drop excursion to almost nothing in the driver's operating range unless operating at extremely high spl's.

Your best bet to improve on this is looking for a driver with higher sensitivity, which usually means higher fs for a given diameter, which for your design will require ported rather than sealed for an extended mid-bass response.

What's your budget per driver?

 

[ro9397]

IF you are disappointed with the dynamics of virtually any driver, then you may well be disappointed with any substantial array - no matter how dynamic-sounding the driver is.

Thanks for your help.

In liveliness and dynamic snap drivers range from soft and compressed to extremely lively. Searching for more of the latter and less of the former.

That "dynamic" sound is often a function of excursion under normal operation (..and includes force/mass/sensitivity etc..). Large arrays drop excursion to almost nothing in the driver's operating range unless operating at extremely high spl's.

I omitted the following because I wrongly presumed it was not pertinent to the driver search.

The application is unique, inspired by Toole's earlier theories. There are two matched monitors (above 80 Hz) per channel: one main monitor + one effects monitor located separately and away from the main monitor, providing a unique radiation pattern. 86 dB x 4 drivers + effects monitor yields about 93.5 dB total.

Space and image effects exceed all other radiation patterns. "Sound density" is also exceptional.

The specified power rating (50Wrms x 4 = 200Wrms) yields 9 dB more than the current speakers, which I presume is plenty adequate. Higher sensitivity is OK.

Your best bet to improve on this is looking for a driver with higher sensitivity

See above. Please quantify "higher."

which usually means higher fs for a given diameter, which for your design will require ported rather than sealed for an extended mid-bass response. What's your budget per driver?

Let's put the cost issue this way: we'll have to scrap this plan even though signs suggest a new performance benchmark, if the only drivers fitting the bill cost as much as Scan Speak Revelators.

Would be nice to find something under $75 MSRP, even better half that cost. Twenty four drivers per system adds up quickly, especially with six cabinets per LCR system.

Thanks again!

 

[ScottG]

This is a good place to start your search (PE search with 5" to 6.5", pro section, price low to high):

Woofers, Subwoofers & Midrange Speakers in the Speaker Components Department at Parts Express | 31 - 497|3917,3918,3919,3920


Of the grouping these look like they will give you most of what you are looking for:

Eminence Beta-6A 6-1/2" High Power Midbass Woofer 290-662

http://www.parts-express.com/pedocs/brochures/290-662-eminence-speaker-beta-6a-brochure.pdf

You'll need to play around with different tuning freq.s to see what's most appropriate to your design.

For a bit more money with lower power handling but greater linearity there is the B&C mid on the list (..also measured in Zaph's 6.5" test grouping).

Note that pro drivers generally need a fair bit of "break-in" when compared to "hi-fi" drivers (..pro drivers have stiffer surrounds when new).