Best way to measure IB bass with Behringer DEQ2496?

[mazeroth]

I'm installing an IB sub this week in my basement theater room and was wondering the best way to measure the response utilizing a Behringer DEQ2496 with the Behringer ECM8000? The DEQ2496 is being used in my 2-channel rig and I will be installing a Behringer Feedback Destroyer Pro in the theater once it arrives.

The only method I can see is going to "Meter" mode and selecting page 2, where it displays the current SPL and also displays the peak to the right. Is this the correct way to measure? I have a computer I can hook up down there and was going to play test tones thru WinISD. I would use some sort of measuring software but I lack a phantom power for the ECM8000 and the sound card is a built-in.

Lastly, the DEQ2496 measures 1/6 octave starting at 20hz. Will she be able to detect sub 20hz bass? I'm sure it can, but am just wondering. I'd like to dial this thing in flat to 10-15hz!

THANKS!

[paulspencer]

The ECM mic is a good choice. Ultracurve can supply phantom power for it - this is controlled in your settings. DIY mics may not be able to handle phantom power as the voltage may be too much, or so I have been warned. That said, I use one without problems.

The range is limited to 20 Hz.

Go into RTA then select "auto eq" ... before it initiates auto eq there is a fullband noise signal and the RTA will show the response. You will get an instant snapshot that way of in-room response.

Why use BFD when you have it built in to ultracurve? Or are you using them in different rooms?

[brucemck2]

I've had more success using TrueRTA than the built in functionality in the DEQ2496. Better GUI for saving and comparing multiple measurements has been particularly helpful.

A related question for the experts ... I too use a DEQ2496 to EQ my subs. It's in the chail after my surround processor. What would be the proper way to account for the extra time delay due to the EQ?

I assume there's a "standard latency" for the unit, so that I can set the distance on all of the other speakers to some longer distance in order to compensate? What would that "extra distance" be?

[noah katz]

"What would be the proper way to account for the extra time delay due to the EQ? "

Use RTA to look at system output at the sub XO freq, and adjust for smooth output there.

If the mains and sub are out of phase at XO there will be a dip in response (although room modes could cause one there as well).