Hello Andre,

(Andre Yew) wrote in
:

...
I disgree about the cost of room correction systems. Research seems
to indicate that at least 1 second of room correction (or 1 Hz
correction resolution) is desirable. At 44.1 kHz, and done with FIR
filters, this amounts to about 44.1k*44.1k = 1.9 billion multiply and
additions (MACs) per second, and over 8 billion MACs per second for 96
kHz processing, a sample rate at which many receivers and surround
prepros are operating at today. That is well beyond affordable, and
even achievable. Top-of-the-line Pentiums and Athlons can barely
achieve Dhyrstone MIPS at half these numbers, and those numbers are
unrealistic and inflated anyway, given that Dhrystone isn't a
realistic, or even meaningful benchmark.
...

I think you should take a look at this site:

http://www.ludd.luth.se/~torger/brutefir.html

Realtime FIR filtering with better than 1 Hz resolution at audio sampling
rates is available since at least 5-8 years. A top-of-the-line processor
should be able to run at least 30 channels at 96 Khz using a program like
that. The main problem is that this convolution method is patented by
Lake Audio, so it cannot be used outside free programs like the one
above, but AFAIK the patent is going to expire within few months.
If you use the program above with the following one:

http://freshmeat.net/projects/drc/

(incidentally developed by me you can build a good quality room
correction system almost for free. You can see some example results
achieved with the program above, along with traditional room treatment,
at the following URL:

http://www.avsforum.com/avs-vb/showthread.php?s=
24df513b860d46cb4eb85577a6528c9a&threadid=283878&p erpage=20&pagenumber=16

And that's just for the implementation of the correction playback
side. The measurement side that determines what needs to be corrected
has its own set of challenges, which include a simple enough user
...

I agree, making a good quality RCS is difficult, making it easy to use is
near to impossible (DRC is definitely difficult to use).

Bye,

--
Denis Sbragion
InfoTecna
Tel: +39 0362 805396, Fax: +39 0362 805404
URL: http://www.infotecna.it