Well, that right there is why the sound is not the best, as a tube amp and those woofers are not a good pairing, much less through a passive XO. And 70w is not enough for those panels, and worse due to losses in the XO.
But since you intend to switch to a more powerful amp, you should see better results with the EP driving the passive. But it's still a passive XO, not even the mighty Sanders ESL amp will make that sing.
Thanks for sharing further details about the gear, as that is key to understanding how various options will fit.
Both of your current front ends are integrated models, with pre-amp and amp in a single box, and neither seems to have a pre-out / amp-in loop, which is required to insert an active crossover. So the effort to go active is over unless you are willing to consider fully separate pre-amp / amp options.
Yes, the tech in this thing is pretty cool, but it's been around for two decades. It does depend heavily on the setup software to load and set configurations, so one needs to be comfortable using apps on the PC. And due to its nature as an auditorium-scale management system, it has concepts such as 'Venue' and finally gets down to devices and then presets for the devices. So a bit of unnecessary complexity to manage a single box, but it doesn't really get in the way too much. Then again, I've been in the computer software development space for 45+ years, so what I see as straightforward, may not be to others.
So if comfortable enough driving an app like that to load the pre-made configurations I can send you, the hard stuff will be done for you. The only configuration tweaks we might make are adjustments to input/output gains to match your gear, and the delay settings on the subwoofer output, again, to fit your physical setup.
But, I'll stop there and double-check that the whole active XO path is one you are willing to pursue, as it requires several things to achieve a successful outcome:
- Front-end is a pure pre-amp with line-level, volume-controlled outs (balanced preferably)
- Two amps, one for panels and one for woofers, matched to their respective roles (balanced ins)
- An electronic crossover, DSP-based preferably but could be a fixed analog active XO
- Crossover design that suits the Monolith (I can supply that for the DBX)
- Measurement system to validate settings and setup, REW software, and a UMIK1 microphone
Right now you have none of those (well, #4), so maybe a rethink of the overall project, as this is both complex and costly. But if willing to go all-in, the results can be impressive.
However, as I usually counsel here, your number one bang-for-the-buck improvement is going to be acoustical treatments of the room housing the ESL setup. And those large Monolith ESL panels need a LOT of room treatments to tame them. A full ton+ (literally) of room treatments in my dedicated room.
So maybe look at deploying the EP amp (since you have it) and look at improving the acoustics. A few hundred bucks there goes a long way.
