"Arny Krueger" wrote in message ...
"dangling entity" wrote in message
om

Wouldn't BagEnd (or something like that) be a better example of the EQ
boosted system you described?

Why do you say that?

Does this name not ring a bell, or are you saying it doesn't fit the
description at all? I was to understand that the product (if I got
the name right, that is) is basically a woofer put into a
smaller-than-usual sealed box, and a complementary bass boost is
applied in the built-in amplification to give the rated frequency
response.

The Sunfire drive is basically designed to "live" in a small box (in
conjunction with a similarly aspiring passive radiator), inherently.
Whether or not there is EQing involved, I'm not exactly sure. It's
really just an extreme take on a conventional vented design, AFAIK.


How does Sunfire do it wrong, btw?

Presumably driver parameters have a lot to do with it. In short, not enough
Xmax. The passive radiator needs to have *enough* Xmax, as well.

Once upon a time I saw Dumax test results for a larger Sunfire woofer
driver. I can't remember too many details except that at the time, they were
considered to be suboptimal for a product that would be loud and linear down
to 20 Hz.


Well, I wouldn't say Sunfire drivers are exactly lacking in the Xmax
category. When considering 20 Hz output however, just about anything
short of a large diameter driver is going to stress the Xmax
capability at even moderate SPL's. I think the Sunfire subwoofer
products present a sort of odd paradigm between compact form and low
frequency capability. The compact form naturally leads to smaller
driver sizes, but those drivers tend to do well in the low frequency
range where other drivers of similar size would not. The particular
driver parameters in combination with the extreme box loading in a
Sunfire enable a capability that not just any 10" driver (for
instance) could do if slapped into a box of that size. That's one
source of the "mystique", I imagine.

That said, a lot of people confuse that capability as a means for
"unlimited sub-bass output", regardless of room conditions. What the
Sunfire does, it does fairly well in a *smaller sized room* (which
would unsurprisingly benefit the most from a very compact subwoofer
design). Naturally, if you put it in a medium or larger sized room,
you will need more units to make that 20 Hz-ish range accessible.
That's just plain physics (not that I'm preaching to you), and there's
no way around that- not even for a Sunfire. I imagine a lot of people
had unreasonable expectations for the product when they put just one
in their medium sized room and expected to be palpitated with air
pressure waves. Naturally, just *one* Sunfire unit would find itself
overextended in such a situation, but people were evidently expecting
it to create miracles. That's my take on it, FWIW.


Finally, I think the one primary compromise to such systems is
increased modulation distortion due to the VC modulating the permanent
magnet circuit of the motor under high current drive levels (as would
likely be encountered with a system that implements high EQ boosts in
the lowest frequency range).

This doesn't seem to be a problem, at least with the Clark implementation.


It's a phenomenon that effects virtually all VC style speakers. Some
are better at minimizing the effect than others, of course.
Naturally, there are few, if any, loudspeaker manufacturers that care
to expose that sort of information about their product (if they have
even bothered to discern it). I don't believe Clark's Duomax
measurements would necessarily reveal its effects, either, unless
studies are expanded to study (very) large signal inputs, rather than
just standard small signal inputs to determine motor strength.