Originally Posted by Bryan R. Tyler
I remember talking with BigChiefBC about it as he had both; he expected the new one to be pretty much just like the old one, but found the old one to sound better (to what extent I don't know).
The BMS has always been one of the core pedals of my "sound". So when EHX came out with the XO version, I was so excited to go down to 9V power and save a little space, but I was disappointed. The voicing of the filter is different, both the resonance and freq range. It's not bad, per se, but I was hoping it was going to sound identical and it doesn't.
And the octaver reacts differently, as well. I'm not saying the old one tracks perfectly; as a matter of fact, I like to play chords to have it glitch out on purpose. But when the old one glitches, it bounces around really cool and musically. When the new one glitches out, it mostly drops out instead of bouncing around. Some may prefer that, but I have a song that depends on that bouncy glitching.
The XO one is not a bad pedal, I could see some people preferring it. But it wasn't as good for my needs. I will echo someone above that if you get an old one, definitely get it modded for true bypass, the old bypass is simply dreadful.