Folks,

As some of you know, over the past few months I've been setting up a home
theater in my living room. I recently installed substantial acoustic
treatment including bass traps, added a 5.1 receiver with more loudspeakers,
and made other improvements like floating the main speakers on rigid
fiberglass to avoid structural transmission for a flatter low end response.

The last detail was getting a decent subwoofer. My wife's McIntosh speakers
are nearly 20 years old, yet they are still excellent and flat down to about
60 Hz. But a modern system should be able to reproduce accurately down to at
least 30 Hz - thus began the quest for that lowest octave.

After trying several brands I bought a Carver Sunfire (photo:
www.ethanwiner.com/misc-content/sunfire.jpg) and it is simply one of the
coolest things I have ever owned. I rarely blab about my audio gear, but
this box is truly significant.

First, it's not a loudspeaker as much as a piston. It's controlled by a
digital switching power amp having enormous output power. The box is only 11
inches cubed, yet the primary driver's physical displacement is a staggering
three inches. No matter how hard you try you simply cannot keep your hand on
the cone at high levels. It's like being struck with a jack hammer. I've
also measured the response and played sine waves. I couldn't verify the 16
Hz lower limit claimed - the cone looked right though I heard only wind -
but it kicks serious butt at 25 Hz.

Of course none of that is relevant - all that matters is the sound. Well,
for the last several nights I have spent HOURS in front of my system,
playing music VERY loudly, yelling over and over, "This is unbelievable!"
And so it is. If you are at all interested in subwoofers, you need to
experience this sub for yourself. It will rock your world as it has mine.

--Ethan [not affiliated in any way with Carver]

Too bad you missed auditioning a Contrabass from my company:
www.servodrive.com

John "Lemmee rock your world-literally" Halliburton

I'm impressed. What are the price points on the two Servodrive units, and
what is the "Power Compression" spec all about?
$2500-3500 "Street" We have customers with Basstech 7 used or our factory
demos that would sell for around $2300 each I believe.

Power compression is the limitation of output due to heating of the voice
coils. Impedance can double in less than a minute on a regular driver, and
cranking up the amplifier to compensate hits a point where no appreciable
sound output occurs. Vented gaps on woofers are a response to this problem,
and do help. On the Servodrive products, a motor replaces the voice coil,
and the difference in wire gauge and wire mass in the armature vs the voice
coil is massive. The thermal rise in the motor is more like 30 minutes, and
in use, stays much cooler, resulting in lower distortion, and greater long
term output. In the Basstech 7, we use a blower fan powered by some of the
input signal, and almost eliminate any power compression. I should mention
that power compression in a standard loudspeaker woofer can be upwards of
5-6db, and in our products it is lowered to 1-2db. This is like free
amplifier power or adding more loudspeakers.


Best regards,

John

John,

Too bad you missed auditioning a Contrabass

Wow, that looks truly awesome. It's a little out of my price range, and
kinda big for my living room, but those specs are really amazing. Thanks for
the heads up. I like to keep current with what's out there. You should do
well with it.

--Ethan

"Ethan Winer" ethan at ethanwiner dot com wrote in message ...



I couldn't verify the 16
Hz lower limit claimed - the cone looked right though I heard only wind -
but it kicks serious butt at 25 Hz.


Did your house feel like it was haunted at 16Hz?


Peter