Digital EQs - how effective are they?

Any EQ adds distortion. EQ IS distortion.

Basically then, it could be said, anything but live sound is distorted, because all equipment adds distortion to some extent.
Using an EQ thoughtfully to correct driver output, I would have to say, minimizes distortion.
 
First, I'm glad you got the situation worked out....whatever method it may have taken.

Second, I'd be very interested in hearing the gory and graphic details of your attempt at implementing an acoustic treatment scenario...if for no other reason just so I'll know what kind of space and what kind of panels (eight of them, no less!) couldn't get content below 200Hz under control. Got a link?

No link, but I had 8 Echobusters panels (experimented with both flat against the wall and spaced) and 2 pretty large GIK Acoustics bass traps. Echobusters is, I believe, now out of business. Measurements showed that pretty large variations in response (5-6 dB) remained.
 
Ok, found some pics of your space (and remember it now...nice!). You do indeed have some funky boundary layer configurations in that room which I could easily imagine creating a number of challenging issues that would require quite a bit of effort to overcome with acoustic treatments alone. I can see a good DRC unit not only simplifying the process considerably, but (just as you said) accomplishing things a modest treatment scenario simply can not.

I did get a look at your panels and they can't be any more than 2" thick. My experience has been getting content below 250Hz absorbed with a 2" panel takes about 12" spacing between it and the wall....generally not practical for a living space....and if you have to have the panel on the wall one will likely need about 4" inches thickness (OC 703) to be effective down that low.

And BTW, 5-6db variations in response is not bad at all. If one can have a response curve that maintains max deviations +/- 6db they're doin' pretty damn good! :yes:
 
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I've got a spike @50Hz that remains no matter how far my subs are away from the corners or where I cross them over (@35 to 45 hertz). I've been futzing with the subs and panels all morning and have made some progress flattening the response out from 30 to 200. Taking a break. I'll try pulling the 2" panels further out into the room later and see what happens.
 

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^^^

I'm having a hard time making out your response curve there, but I'd be surprised if repositioning those panels does anything at all for your 50Hz issue, Mike. A 2" panel, no matter how far away from a boundary layer, isn't going to do much of anything below 125Hz. There's just simply not enough material there to trap that long wave. That's several purpose built bass traps territory your dealing with...and if it's a room mode (which I suspect it is since moving the subs doesn't seem to help the issue) you'll likely have to EQ it out to kill it unless you get very aggressive with bass traps.
 
^^^

I'm having a hard time making out your response curve there, but I'd be surprised if repositioning those panels does anything at all for your 50Hz issue, Mike. A 2" panel, no matter how far away from a boundary layer, isn't going to do much of anything below 125Hz. There's just simply not enough material there to trap that long wave. That's several purpose built bass traps territory your dealing with...and if it's a room mode (which I suspect it is since moving the subs doesn't seem to help the issue) you'll likely have to EQ it out to kill it unless you get very aggressive with bass traps.

Response curve rolls off steeply at 200Hz since I'm using a frequency sweep from 10 to 200 Hz:D

Still some work to do moving the subs to various positions within the room and believe more aggressive bass trap treatment might be required given the shape of the room. I've got two turns of >45 degree angles where a corner would normally be and an open door at the other end of the room....no corner there either. :no:

I'll start looking at EQ though but I'm pretty happy with the rest of the gear.
 
I use the Dayton Omni Mic. Room EQ Wizard might be your best bet for measuring your room, David (since it's free software you can download). Google it and prepare for a very steep learning curve.

I get the feeling you won't geek out over waterfall plots and response curves like me. It might be best for you to just get a DRC unit and let it do the dirty work. Even with all my acoustic treatment efforts I'm seriously looking at the MiniDSP Dirac unit....just to get that last 10-20%. Dirac Live Suite is actually a downloadable DRC program, but I'll go for the MiniDSP stand alone unit as I don't think you can use the software if you're listening to streaming music from a laptop and with Tidal fixin to hit here that's probably about all I'll be using as a source for my tunes.
 
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Response curve rolls off steeply at 200Hz since I'm using a frequency sweep from 10 to 200 Hz:D

Still some work to do moving the subs to various positions within the room and believe more aggressive bass trap treatment might be required given the shape of the room. I've got two turns of >45 degree angles where a corner would normally be and an open door at the other end of the room....no corner there either. :no:

I'll start looking at EQ though but I'm pretty happy with the rest of the gear.

Just to be clear, when I suggested EQ I meant any EQ applied by DRC.
 
Thanks, I'll have a look into it.

I don't necessarily believe the best spec is the best sound for me but it is good to have some reference point.
 
The MiniDSP Dirac unit doesn't lock you into an "ideal" or "flat" response....it allows you to start there and tweak to taste. That's a very strong feature IMO.
 
Oh yeah and the panels I have - they can be moved around.
The DRC makes me wonder what I'd do with my turntable if I get one.
 
I might be talking heresy here, mixing pro gear with home audio but this is a piece I find intriguing.

Graphic AND parametric functions. Balanced in/out which the M6i can handle.

Inexpensive but packed with functionality. I could virtually dial out the 50hz modal hump in my room.

Comments, thoughts?

http://www.behringer.com/EN/Products/DEQ2496.aspx
 
It goes downstream of your source, so whatever your M1 does the Behringer redoes with its own DAC.

I'm thinking MF probably has a better converter than Behringer. :scratch2:

I tried a similar unit, the dbx DriveRack PA+, and didn't care much for its sonic contribution.
 
I used the Behringer for a couple of years with good results. I found it quite transparent using digital I/O, just OK using the analog output. I'd certainly use one again rather than go without room correction.
 
I might be talking heresy here, mixing pro gear with home audio but this is a piece I find intriguing.

Graphic AND parametric functions. Balanced in/out which the M6i can handle.

Inexpensive but packed with functionality. I could virtually dial out the 50hz modal hump in my room.

Comments, thoughts?

http://www.behringer.com/EN/Products/DEQ2496.aspx
Very good device. By you have to build uncommon setup with Behringer BEFORE main DAC. I was not very impressed with its ADC and DAC capabilities. But keeping it in digital domain only gave good results. You can use free REW software to dial it in.
 
I just took a closer look at the feature set of that Behringer and with this....

- Balanced inputs and servo-balanced outputs with gold-plated XLR connectors, stereo aux output, AES/EBU and S/PDIF inputs and outputs (XLR and optical)

....it appears the unit could indeed be situated upstream of the DAC so all tweaks occur in the digital domain. If your source is a laptop via USB you'll need a USB/SPDIF converter, but that's no biggie. :scratch2:

I think I'm seeing this correctly....right guys?
 
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