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Room correction, DSP for dummies.

I have not paid a lot of attention to audio for some time, almost 15 years and as a result I am trying to catch up on some of the innovation and tech developments that have been popping up in that time. 

One of the more interesting to me is the advent of electronically guided digital signal manipulation to help quell small system issues and room reflections. It seems wildly promising but  the few systems that I have read about that seem to work well look to be  painfully expensive. 

Reports have seemed to indicate that this technology was making its way into other, more affordable formats but I guess I just don't understand or grasp where the field is going well enough to know where the bulk of the technology is and how its manifesting in our hobby. 

Who can help shed some light on where this tech is, how  its being applied and how can I make use of it without selling a kidney? Maybe that last part is not possible yet? 

Thanks in advance! 
128x128dsycks
recluse
270 posts
 
Just like the title of this thread. A good one and should be a sticky :-)

Is there a product out there yet that is idiot proof or doesn't require a separate highly variable computer interphase or doesn't require downloading software?

IOW, something you can set up after a few spikesd eggnogs. Thanks for your input.

Merry Christmas 
mlsstl
1,438 posts
 
@recluse -- if you want to experiment on a relatively low cost basis, here's an option for you.

Buy a Raspberry Pi 3B+ or 4 ($30 or $40) along with a HiFiBerry DAC+DSP Hat (under $100 and fits on the RPI). A case for the boards, a power supply and an SD card might be another $25.  The needed HiFiBerry OS system is a free download.  Finally, you'll need a measurement microphone with a USB connection; there are a number of options for $100, give or take. 

Set up the RPi/DAC card and use it as a player into a line-level input on your stereo. The HiFiBerry OS has an option where, using the measurement microphone, it will measure the frequency response of your speakers in your room.  Once done that'll show you a graph of the response and give you options to make corrections -- bass only or several broader choices. 

The OS also has the option to do custom equalizations if you have others ideas in mind. 

Obviously this is something that requires a LOT of experimentation, but it gives an effective way to investigate your DSP options without throwing down big bucks. 
mijostyn's avatar
mijostyn
8,570 posts
 
dsyckx, check out my system page and you will see an advanced DSP system at work.
yyzsantabarbara
4,909 posts
 
Same with my page.
mijostyn's avatar
mijostyn
8,570 posts
 
Erik, the best room correction systems merely create a mirror image filter to the speakers frequency response in a given room and give you the arrival time of each individual speaker. Some will also calculate the delays required to make the sound of each speaker get to the microphone at the exact same time. After that all the choices are yours. Unfortunately a large proportion of clients had no idea what to do with those choices and made a f---ing mess out of it. So manufacturers started making those decisions for people such as with DEQX and Anthem units but even with these units if you care to dog deeper you can wrestle control away from them. Most are not so inclined.
You can not just ignore the room. You still have to block early reflections and set up subwoofers correctly. The filters can only do so much. 
IMHO you can not get to the seventh level without correction but you have to do everything else with it or it is just a waste. 
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