Wondering what the soundmen were doing

[LiquidMidnight]

Hey everyone,

I was just wondering if you could answer a question. Last night, the soundmen we were using did this thing while setting up in which they placed a microphone out on the floor (on a stand of course). For about 5 minutes, it sounded like a 747 was taking off through the mains. I think they were tuning something. It was neat, and I was just wondering what they were doing (forgot to ask them the purpose at the end of the night).

[Munjibunga]

They were "pinking the room." They set an RTA (real-time analyzer) mic out in the room, generate some pink noise at performance volumes, and their Driverack automatically sets the approximate proper EQ for the room. Once you get playing, they can tweak the EQ to suit their ear.

[cirwin]

For those who don't know the jargon - "pink noise" has equal energy per octave as opposed to "white noise" which has equal energy per freq. (Since each higher octave is a doubling in freq, white noise has twice as much energy per octave and sounds "hissier".) Since any room or structure will favor certain freq and not others, using pink noise with a freq. analyzer allows the engineer(s) to "tune" the PA system to the room. And as MB points out, tweaking happens once the actual performance starts.

[P. Aaron]

Cool..."pink noise" rhymes almost with...Pink Floyd.

[LiquidMidnight]

Awesome, I guess you really do learn something everyday. I don't know if our regular soundmen do that or not, since the PA is usually set up by the time I arrive at the club, save maybe a few monitor cords.

I don't run pro-audio, but it's been intriguing me as of late.

[tommixx]

The dbx Driverack is a thing of beauty....we used to do it the hard way but the Driverack now makes it a simple thing to do...input your PA, tell it whether you are running mono or stereo, define your power amps and bam!! After a minute (or less sometimes) of a jet taking off you are ready to play.....HIGHLY recommend them to anyone who runs their own sound....you can pick them up at GC for less than $500!!! They also time align, phase correct, EQ, Limit, Add subharmonic enhancement (bass management), and Suppress Feedback....Mine took over the work of about 12 spaces of gear in my House rack!!! ALL IN A SINGLE RACK SPACE!!! Can you tell I like them?

Peace,

T

[Justice]

The DBX Driverack PA is nice and does do all the things you mentioned, but it does have one major flaw. IF the power cycles causing your DRPA to shut down while your amps are on, it will send a large spike through your system (sounds like a gunshot when it happens) and has the potential to destroy your drivers. It amazes me that as long as the DRPA has been out that DBX has not (asfar as I know) corrected this problem. So you can do yourself a big favor by adding a UPS to your rig so that you minimize the chance of the DRPA losing power.

Also, it seems like the Driverack PA is the only one that suffers from this problem, the other Driverack models do not (like the 260)

I used to run a PA with a DRPA in it and one time the guitar player reached over and cut the power to the DRPA and *BOOM* about jumped out of his pants. This was AFTER I warned him not to do it. (The Driverack was the first thing that gets turned on and the last thing to get turned off) We were luck that time, no speakers damaged.

[tommixx]

Not to derail the thread but I have never had that happen....I run several different systems for other bands who have Driveracks and I have never seen it in there's either.....Go figure...

Peace,

T