Ok, the results are in. DJPhatman was kind enough to lend me his ear. Of course he had ulterior motives, trying to decide himself which cab to build! I think when all said and done we walked away with some very useful information, and had a few surprises along the way.
To perform our by-ear tests, I ran a CD into an input on my board. The signal was mono to ensure the same information was getting to both channels. Both channels were EQ'd dead flat, with the exception of 40Hz down which was removed from the signal.
Drivers in the test cabs are as follows: DR-250, Deltalite 2510; DR-200, Beta 8; OTop 12's, S2012; Omni 10's, Deltalite 2510.
Piezo arrays are as follows:
DR-250, crossfired; DR-200, 2 crossfired, 2 straight; OTop 12's, straight; Omni 10's, crossfired.
The first test was a single 200 Vs. a single 250.
The very first thing we noticed is that the DR200 sounds better with no EQ. With the EQ flat, it beats the 250 soundly. There is a cohesiveness, or clarity to the sound that the 250 doesn't have. After some discussion we agreed the best way to describe the sound was 'tight', The 250 goes lower and is slightly louder. It took about a 1.5dB boost in the gain on the 200 for our ears to call them equal in volume. Once the 250 was EQ'd, they sound very similar, the 250 still winning in lows, the 200 still winning in overall clarity and sound.
Second test: 2-200's Vs. 1-250.
200's win, easily. The lows started to come out more, and the mutual coupling was very apparent. In order to keep things as even as possible, we cut the gain on the 200 input by 3dB since they were receiving (almost) twice the power. They still won.
Third test: 2-200 Vs. 2-250's.
Now things are starting to tighten up with the 250's. They still wanted some EQ to flatten response, but far less. The mutual coupling between these cabinets was in-your-face-obvious. The 250's won in volume and lows. The 200's needed a gain boost of 1.5dB to equal them. However, the clarity of the 200's was impossible to ignore, and they took that category for the third straight test.
Fourth test: 3-200's Vs. 2-250's.
This was very, very close. 3 DR-200's equal 2-250's in volume, and it's possible they even have a slight edge. DJphatman thought the 200's were a bit louder, I couldn't decide. But they're equal at the very least. This was done with the gain cut by 1.5dB to take into acccount 2.6 ohm load from the third cabinet. The lows were very close as well, it would've been tough to make a call.
Fifth test: Adding subs.
For this one we simply used a pair of Tuba 24 MkII's, 16" wide and ran them with two of each cabinet. Once the subs were added, it was a toss-up. Both system were absolutely killer, neither holding an advantage over the other.
Sixth test: 4 DR-200's and subs
We did this strictly for shits-n-giggles since there was nothing to compare them with. The result? IT WAS INSANELY LOUD!
Summary: For single cabinets the 250's have the edge in volume and bass. If you're running without subs, or want to cover a 200 seat room with a single pair of cabs, the 250's win. Once you start stacking them the 200's have a huge advantage in size, weight, and build cost.
The one single unwavering factor that showed up in every single test was the
absolute crystal-clear sound that the DR200 provided. It was there every time, regardless of the setup.
And here's a pic of them together. The few inches doesn't sound like much, but setting next to each other the difference is obvious.
Now for other tests.
DR-200 Vs. Omnitop 12
Once again clarity goes to the DR-200. The Otops had a slight advantage in the lower mids, but also needed a bit of EQ. Volume between the two is virtually identical. The DR won this by a nose in overall sound, however, if you never sat them next to each other to A/B, you'd never know the difference. Choose either one and you won't be wrong.
Omni10 Vs. 2-OmniTop 12's
DJPhatman was kind enough to bring his Omni 10 over so we could see how it stood up. The result was surprising based on the SPL charts. We both expected the O10's to beat the 2-12 OTop in low end, but the OTops won out. That's where it ends though, the Omni 10's clearly had the advantage from the mids and up. Volume was comparable.
Well, that's it. I'm satisfied that we did this as fairly as possible, taking care to adjust gain as needed so the larger array didn't hold an unfair power advantage. I'm sure you could get closer with the right equipment, but I'm not sure you'd get different results.
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