"Joseph Oberlander" wrote in message
news
Arny Krueger wrote:

"chunky_john" wrote in message
om

(Tried posting this on rec.audio.high-end. Got lots of advice, but
no-one actually answered my question...)

Current system: Marantz CD63 KI Signature, Arcam 8/8P biamped to
Monitor Audio Gold Reference 20s via Chord Odyssey 4. Interconnects
are Cambridge Audio Studio Reference.

Have just upgraded speakers & cables. Very nice!. What next?


http://www.audiorevolution.com/equip...orgoldtheater/

Ah. I see. He already HAS the 20s.

Right, and this article suggests other components to match up with them.

Even if he doesn't buy into the surround sound approach, he might take
notice of the subwoofer(s).

So change my reconnedation to a 5.1 setup like Arny suggested.

Or, just enhanced 2-channel with more clean and deep on the bottom end.

Add another amplifier for the center channel and add surrounds.

as he prefers.

The two amplifiers you have are overkill - you don't need to
biamp - so there are 4 of your 5 channels already.

Good point.

As for a subwoofer(if you want one at all) Martin Logan makes a very good
servo sub that's accurate and fast.

Joseph, some day I'll figure out how to explain the myth of fast bass, in a
way that you will understand. Maybe I'll get lucky today!

My last shot at it on another forum pointed out that subwoofer crossovers
are low pass filters in the 50 to 150 Hz range. 12 to 24 dB roll-offs are
common. Even an 18 inch subwoofer has a natural rolloff that is someplace
above 500 Hz, normally 12 dB/ocatve. If you cascade any kind of serious 150
Hz low pass filter with a 500 Hz low pass filter, the 150 Hz is tremendously
dominant. At 500 Hz, a 125 Hz 12 dB filter is something like 20 dB or more
down. So, the effects of relative difference in the *speed* of the subwoofer
driver are completely blown away by the crossover that is always there.

Now for a discussion of the *real* issue. Every room has a frequency,
inversely dependent on its size, where the room starts producing a
sifnificant bass boost. This boost may or may not be mixed in with otehr
audible effects due to standing waves. Its always there if the room has any
integrity as a closed volume.

Very few subwoofers are designed to be flat in free space. They are all
tuned to have a roll-off that is compensated by some presumption about the
space where the subwoofer will be used.

On a good day, the subwoofer comes with a specialized parametric equalizer
that allows you to tune it to any reasonable room. On a slightly worse day,
the user provides his own equalizer, hopefully a parametric. On a slightly
worse day he uses a 1/3 octave graphic eq. On most days, miseducated to
pathologically fear equalizers by the high end establishment and its dupes,
the hapless audiophile has no control over the situation other than buying
and selling subwoofers until he blunders into the right one.

If you use a subwoofer that is designed for a small room in a large room,
the sound is going to be thin, because the subwoofer's roll-off is well in
force by the time we get down to the frequency where the room starts
helping.

If you use a subwoofer that is designed for a large room in a small room,
the sound is going to be thick and thuddy, because the subwoofer's roll-off
isn't going to start until we get well below the frequency where the room
starts boosting the bass.

And so, we have a lot of poorly-informed discussions about non-existent
things like fast bass, because people don't properly match subwoofers to the
room they are listening to them in.