Semi OT - Graphic EQ with RTA

[smanzella]

I think that it is generally accepted that most modern digital pianos sound pretty good through the store's studio monitors, headphones, or on recordings. It is when these instruments are played through most 2-way keyboard amps and speaker cabinets that they tend to come unravelled. They typically sound "boxy" and "mid-rangy". One thing I did to solve this problem at my permanent performance venue was to buy 4 Acme B-1 cabinets powered by a Crown ITX 2000 power amp. This works very well for me. However, I often play out with a few other big bands or jazz orchestras that typically prefer acoustic piano sounds as opposed to electric piano sounds. I usually carry a small combo amp such as a Yorkville 50KW or Peavey KB60 for these occassions. These amps have more than enough power for these gigs and they sound fine on everything except for acoustic pianos. I have tried out some other amps from time to time (Motion Sound KP200, Barbetta, Roland KC550) with about the same results. This leads me to the conclusion that just about all amps give about the same results. The problem for acoustic pianos seems to lie in two areas:

 

1. The lows are not powerful enough

2. The low mids (200 - 400 hz) are too prominent

 

The EQ controls on just about everything I have ever played through are wholely inadequate to address these problem frequencies.

 

One thought I have had for some time is whether these problems could be solved by a unit such as the DBX DriveRack PX (http://www.dbxpro.com/PX/index.php). This unit has a 28 band graphic EQ with a pink noise generator and real time analyzer. My understanding is that this unit allows you to analize a room using pink noise and set the eq so that various frquencies are boosted or cut to compensate for their excessive or inadequate presence through whatever speaker or amp is being used. In effect, I should be able to "flat" my amp for the room I am playing in by using such a device. If the response of the amp is flatter like studio monitors or headphones, then my accoustic piano patches should sound closer to the way they sound when played through studio monitors or headphones.

 

Has anyone ever thought of or tried this approach? I am about to buy one of these units to test this theory. Before I do, I want to know if anyone else has ever tried this and with what results. It seems to me that if one of these units can "flat" the amp, just about any amp can be a good amp.

[DanL]

we have the driverack in our PA. you most likely will not be able to use the pink noise analysis in a room you are playing unless you get in there well ahead of time when no patrons are around. Its obnoxious and you have to crank it up pretty loud to get a good result. What we did was hook up our PA in the basement, run the analyzer and save the preset- that gives us a reference point to start from. We told it to EQ the system flat, and have found that the response from our speakers sounds like there is too much low mids, and we end up using the EQ on the back of the speakers to compensate. We're going to bring them back down in the basement and have it EQ on a curve and see how that helps.

 

I think it'd be overkill for a keyboard setup. You might try borrowing a graphic from someone, play around with it and see if it does what you need, and then decide if you want to buy one. Using your ears is just as important as using an automated tool, if not more so.

[mate stubb]

I used an RTA to set the basic flatness of my Accugrooves in an isolation booth at a recording studio.

 

It is not as good as setting it for each room, but the EQ changes in the room anyway after all the warm bodies show up.

[smanzella]

After observing a few audio engineers set these things up at performances, I figured that the ears were much more important.

 

Dan, I'll probably follow your advice and play around with a regular graphic EQ. Any suggestions?

 

I'll be playing with a jazz orchestra this weekend and will be using my Kurweil SP2X with my Yorkville 50KW or Peavey KB60. This setup sounds good in some places and no so good in others. I suspect that EQ would be the best way to solve this problem.

[Sven Golly]

Sorry, but this is all just lipstick on a pig. Get something better than the 50KW or KB60 rather than try to band-aid a solution.

[Bill H.]

Sorry, but this is all just lipstick on a pig. Get something better than the 50KW or KB60 rather than try to band-aid a solution.

 

Yeah I agree. You just can't EQ your way out of bad amplification. These are frankly horrible amps for acoustic piano, and absolutely nothing will save them.

 

I've used the RTA on my Driverack for my PA and it's not all that great of a tool either. If you move the mic just a little one way or the other you get a different curve, and none of them are going to be what the room is going to sound like when it fills up with people. Your ears are pretty much your best bet when it comes to EQ.