Re: Room correction (Was Progress?)

Hi Daniel,

> I figure if it's possible to build this kind of technology into a 
> monitor speaker, it will (eventually) be possible to run it on a host 
> CPU. That doesn't necessarily mean it's practical yet, of course.

Yes that's reasonable.

> > Most room
> >anomalies are caused by reflections and simple EQ cannot correct this.
> 
> Quite, that's why we were just talking about Ron's time-domain 
> correction project.

Sounds interesting.

> >Only minimum-phase effects (eg. bass boost caused by wall loading of
> >loudspeakers) can be compensated for like this.
> 
> I've heard that's the case, but then I've also heard it pointed out that 
> bass absorption is the hardest aspect of room balance to get right, so I 
> can see the approach might have some merit.

Especially in the pressure zone, where frequencies have a half-wavelength
smaller than the longest room dimension. These frequencies can
be EQ'd successfully, and the smaller the room the higher the pressure
zone goes. Good news if you monitor in a small room.

> 
> > it will only improve the sound
> >in one small area (it'll be worse everywhere else).
> 
> True, but then in the context of nearfield monitoring there usually is 
> only one listening position.

True at low frequencies. At, say 6kHz, wavelength is only about 56mm. 
That's a pretty small listening area! Fortunately it's easier to absorb
high frequencies than low ones as you correctly point out.

> Having said that, I am naturally sceptical about snake-oil products from 
> studio equipment manufacturers. I've followed the recent discussion 
> about analogue summing amplifiers for DAWs in Sound on Sound with 
> interest. According to a columnist in the latest issue, they are 
> completely useless; the reason mixing in the DAW often sounds worse than 
> analogue is because most people keep the DAW track faders at zero, and 
> the master gain fader pulled right down to keep the output level 
> reasonable. This means there are no clips on the output, but the DAW's 
> internal mixer is completely overloaded, causing nasty digital 
> distortion. I can hold my hand up and say 'Guilty!' to that one :-)

I have heard reports from high-end users (who could reasonably be
expected to set appropriate fader levels) that analog summing can sound
better than some DAWs. Of course, by the time something gets put on a
CD nobody will hear the difference (and how long will it be before CD
is relegated to the same audiophile niche now occupied by vinyl, in favour
of MP3?). I've been using analog summing for years - I use an analog
desk for mixdown ;).

John