Room correction, DSP for dummies.

I love DSP, but it is no panacea, and no magic computer that gives us the right answers.

I agree with most of what @grannyring said, but I feel this needs more discussion:

Room Perfect room correction takes the room out the equation and
deals with these room sound degrading realities. The speaker is now able to sound as it should without room editorializing and degrading.

The problem here is that we are honestly dealing with a number of personal choices that make it into software. There is NO room correction software that uses a purely objectively neutral curve. None. They all pick among possible good target curves and make choices about the detail level of the correction. This is a reason why I prefer to do my own EQ, and really like JL audio. They use the same curves I do, but cost about $15k more per sub than I pay. :)  

Further, there is no room correction software that works as well as it would with bass traps. So, yes, in a bad room EQ is better than nothing at all, but not nearly as good as EQ + bass traps and proper sub placement.

Also, let's face it, a lot of highly touted "high end" speakers are not objectively neutral nor are they smooth to begin with. If you buy a speaker for the sound, and you DSP it, your speaker selection and room correction can really be at cross purposes.  The point is, not all room correction software is the same, or moving to the same goals you are. You should absolutely listen to a variety and see which suits your needs, or which can bet tweaked best for you. 


Best,

E

craigl : 

Thanks, I don't need more room measurement/microphones or DSP toys. :) 

I built the correct EQ into my speakers instead. I use DSP modestly. On the sub and on the center channel (depends where the center is). 

Best,

E

the room correction assures your speakers sound as the designer intended in your particular space.

The speaker is now able to sound as it should without room editorializing and degrading.

@grannyring  Bill, thanks for your response, but it still doesn't clarify things for me. I'll try with more specifics. 

What you are saying begs the questions:

- how does room correction know which speakers you have? Yes, some speaker manufacturers provide their specifics, but how complete are these? Is this a perfect system? Is it based on anechoic figures? If so, can one's real life room ever be anechoic?

- how does room correction know what the speakers sound like or are designed to sound like? This isn't a simple question. ["sound as it should"]

- which leads to the far trickier how do you know what the speakers are supposed to sound like? 

- or that your interpretation of the sound is what the designer intended?

- does the designer know what he or she "intended for your particular space"?

- are you trying to re-create the speaker designer's space, as being the ideal? Is it? Do you know it or does room correction know it?
 
There are more, but I'll stop with these. 

I'm sure this is coming across as being difficult, so let me apologize in advance. Looking forward to understanding and learning. Thanks.

@david_ten - I’m sure someone could speak with more knowledge, but the ones i’ve used have a mic that comes with the unit, you put it into test mode and it sends a sweep frequency through the system, starting at very low frequencies, runs the range, then repeats. You can reposition the mic in some cases to try to even out the response in more places in the room, but my Fred Flintstone version is, the little microprocessor reads these sweeps, sometimes a 1/2 hour worth of them, and creates a number of filter sets. When the thing is done with this process, something signifies that (an LED or simply the beauty of silence) and you are in business. It essentially reads the room and creates a filter or set of filters to compensate for the peaks.
I’m using this at a crossover of 55 hz with a very steep slope, so it doesn’t mess with the midrange phase or introduce as many electronic anomalies as it might for a cheap plastic device. (I use a linear PS for it, not the supplied wall wart). I think what it does, sonically, is remove some peaks so the response is flatter. The bass sounds more contained, less amorphous, tighter. I’m reluctant to have such processing in the higher frequencies but I gather that can be done with better units, setting phase, crossover points, an altogether more elaborate device that goes beyond the simple task of smoothing out the bass response in a given room. I think the device is agnostic in the sense that it doesn’t care what the room or speakers are-- it just reads the sweep frequencies it generates and creates a filter set to compensate for them based on some algorithm or set of machine instructions. That’s probably the limit of my technical understanding.
NB> David, I don’t know if you addressed your follow up to Grannyring (whose real name is apparently "Bill" or both of us, since I’m also a "Bill) but you got my response FWIW.

@erik_squires - agree not a substitute for some treatment, including bass traps.