dbx DriveRack PX Powered Speaker Optimizer Review

Aloha!

When setting up the stage for a band or a hall for a DJ performance, there is usually not enough time to get everything right, and sometimes there is just not enough time to get a good sound check in. And even if you get a killer sound check in, the room will change throughout the event as people come and go and the dynamics of the band of music change. That is where products like the dbx DriveRack PX loudspeaker management system come in handy.

You may remember dbx, as they came to prominence in the 1970s for their compressors and noise reduction technology. Over the years they went through various parent company changes (BSR and AKG) and now they are owned by Harman international. It turns out that they still make some very nice live sound equipment, such as the DriveRack series.

The idea of DriveRack is to automatically optimize the operation of powered PA speakers. This system can quickly configure itself to optimize EQ settings for the room, and it uses an Advanced Feedback Suppression system to nip feedback in the bud. The result is a very clean sound and thumping bass that does not get all blurry.

The DriveRack PX is in the lower to middle range of this family of products, but it is certainly good enough for what I am using it for. Besides the features listed above, it also contains a classic dbx compressor, a dual-band 28 channel equalizer, a stereo multi-band parametric EQ, and a subharmonic synthesizer that provides that bass I was just taking about.

The PX fits in a single rack space, and connecting it to the PA system is a breeze. On the back are a pair of XLR inputs, two XLR main speaker outputs, and two XLR subwoofer outputs. Also on the back are an IEC power socket, an input pad switch and a ground lift switch. That is it, and the hardest part about this is figuring out where you want to put it in your signal chain. In my set-up it is the last thing in my signal patch before my powered speakers.

The front of the DriveRack PX is only a little more complicated, and if you can use a smartphone or an iPod it should not take you too long to figure it out. There are LED meters for all six of the XLR jacks on the back, a selector knob, nine switches for functions and set up, and another XLR inputand an RTA switch. What are these for? I’ll get to it in a minute…

Set-up is easy, if you can read a manual and follow instructions. Just press and hold the SETUP switch to create a new preset (many popular powered speakers are already saved in the unit), and the DriveRack will tell you what position to put the speaker level knobs in. Then select your subwoofer settings, and pull out the handy RTA microphone that came with the unit.

Set that microphone up about 25 feet away from the speakers and press the RTA switch, and pink noise will start to come out of the speakers. Then turn the knob until it reaches the sound level that you anticipate for the gig, and follow the prompts on the screen. It will automatically EQ the system for your room. Like magic!

Following additional prompts on the screen, it will walk you through setting feedback filters. After it is all done, do not forget to save your preset, so you do not have to complete all of these steps the next time you set up. Set-up should take no more than 20 minutes, and subsequent set-ups take maybe 10 or 15 minutes (you will need to pink noise the room each time). It is best to not try to set this up for the very first time at a gig when you are in a big time crush – experiment with it at home a bit first.

You can set up to 25 of your own presets, in addition to the ones you get from the factory. Of course, you can make things more complicated if you want to and this unit gives you the ability to spend all day fiddling with EQ frequencies, but if you are that kind of person you would not be buying one of these in the first place.

Once I did all of this set-up and got my first DriveRack-enabled dance gig going I was blown away. I was using a pair of 1000W QSC K12 main speakers and a pair of 1000W QSC KSUBs in a 500+ square foot carpeted hall, and I could immediately tell a difference. There was a lot more presence and headroom, and everything sounded more clearly with no harshness, even at ridiculous volume levels. This is a tough room to EQ, and usually the sound would get swallowed up, but this time it really came alive.

Score one for dbx!

My second experience with the DriveRack PX was at an outdoor punk/hard rock show that I was providing the PA and doing sound for. This time I brought a pair of 1300W Yamaha DSR115 mains with a pair of 800w Yamaha DSR118W subwoofers and a pair of 1000W QSC K12 speakers for floor monitors. This was an unbelievably loud show, but I went through the set-up wizard (not for the monitors, there is only so much this thing can do), and crossed my fingers for the 6 different bands on the bill. The sound was clear as a bell, and with four vocal microphones on stage and countless different singers of varying abilities and vocal strength there was not a single feedback incident over the next 6 hours.

Score two for the dbx, and I am willing to call it a win after this one. I will not go to a gig without this thing in my rack.

Fortunately the dbx DriveRack PX will not empty your pockets. This unit has a list price of $599.99 and a street price of $299.99, which includes the RTA microphone. That is one heck of a deal, and if you are doinglive sound with powered speakers I wholeheartedly recommend that you pick one up!

Mahalo!