Re: Room correction (Was Progress?)

Hi John,

> Don't underestimate the DSP power required for room correction.

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.

 > 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.

> 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.

 > 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.

> `Room correcting' EQ enjoyed brief popularity in professional studios in
> the mid 1970s, but it soon fell out of favour when everyone realized it
> didn't work.

I agree there's no substitute for a well-balanced monitoring room, but 
many people using computer-based recording don't have that luxury. There 
are many techniques that are available now that weren't available in the 
70's, particularly in the digital domain of course.

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 :-)

Cheers!

Daniel