Originally Posted by Mark P
Where do you get pricing and specs? I know the Phifer warehouse here in Portland sells it for $xx a lineal yard through a blinds/ shades dealer but when I was checking out the 5% openess factor it was driving my Audyssey system crazy as compared to the 7% and 10% openess of other products like XxX and Screen research. When placing it in front of one speaker in the front soundstage it was saying that speaker was out of phase and changing the frequency response quite a bit. Is this offered in 7% and 10% openess?
Hi Mark -
I don't have experience with the out-board Audysseys, but the built-in MultEQ in the Denons work without issue. I know the separate Audyssey is a much more sophisticated tool, but the Phifer 4500 has been in several Denon systems: two 3806s, one 4306 or 4806 - can't remember which, and their big 5805, which should come with a built-in hand truck. All but one were center-only-behind-the-screen systems. None of them failed polarity check.
In my system, I've had (polarity) success with other room correction systems. The TacT I had for a while passed polarity checks just fine (only my center channel is behind the screen), but I personally don't like the TacT. Good methodology, but just way too much. There aren't target curves to go for and as a do-no-harm audiophile, I really didn't like how much futzing with the mids and highs the system allows you to use. It made everything behave unrecognizably each time I powered up. I'd get it cal'd to sound great and then later it just sounded completely wrong.
While the science behind the Audyssey is solid, I'm much more skeptical of DSP above the mid-bass range of, say, 300Hz. Correcting for room modes <300Hz is an entirely different animal than other goals >300Hz. And I'd argue the former is a realistic problem to fight with DSP and the latter is a can of worms.
I compared the Meridian and Lexicon room correction systems, and I preferred the Lexicon. Both only address <250-<300Hz, so they just get out of the way of the midrange and treble. The Meridian always passed polarity check with either screen up or down. The Lexicon mc-12b(v5.0 EQ) was unfortunately the winner. It nailed my room modes, dramatically improving tone, pace, and bass transient.
Its cal system has been tricky for me. It fails polarity check around 40% of the time and its users commonly know to just double-check things and if you know everything's in polarity, just ignore the "failure." I ran the auto-calibration on the four woven AT screens I have, and could not find any correlation with any AT fabric and any polarity failure. After 40 cals (4 screens x 10 tests), all four woven AT screens were within +/- 1 polarity failure. That, together with results such as the L or SR channels being the ones that measured out of polarity, or screen-up/screen-down not changing things, point to none the screens affecting the polarity.
One thing to watch for is for systems using horizontally aligned MTM center channels; if you are taking multiple measurements you may run into lobing effects on the center. They can affect your polarity checks as well as complicate the room correction's job in the frequency range of the two midranges.
Finally, I'm not sure what the "-2.5dB at 10k" means. The SW4500 measured 0.8dB higher at 10k, which is of course by itself meaningless but within test uncertainty. If I average the three results around 10k, I get -1.5dB. Five results average -2.1dB around 10k. The nine results around 10k average -1.5dB. Within a responsible context, all four woven AT screens I have measured nearly identically.