I talked to my amp tech about this when I got my HRM and he said it made a lot more sense with these amps to just go the external loop box route. I also hate the extra complexity but it comes with the territory with these amps.

Generally speaking any effect or device that will bring your signal up to "pro" line level (rack effects level) will work in the loop. I successfully used an Alesis Nanoverb to bring the return level up and use my pedal board without a D-later. So if the DBX has enough makeup gain to sit in front of your pedals and bring the signal up then it will work. The Klienulator does a great job of further smoothing of the overdrive sound (as does the C-labor) so you would miss this benefit.

Hope that's helpful

Cheaper / easier to just use a Klienulator?

And I'll cast a vote for the G12-65s which sound stellar in my convertible back 2x12.

For me it's just a curiosity. The HRM sounds so good as is I would not make the
Changes. It's just a monster of an amp with a very wide sweet spot compared to the other d-styles I've played through.

Cripes, I paid $1300.00 US for mine without the Klienulstor (which I picked up after the fact).

I have an HRM 100 and I'd also like to know this. I think it's mainly a difference in the voicing but I think it's across the clean and overdrive channels.

You need a mic preamp to do what you are trying to do. You can pick up an M-audio audio buddy for about $50.00 used.

Thanks guys! Loving this amp. Can't wait to take it out live. The guitar is an Old Moon custom one off with SD P-rails. It seems to get along well with this amp.

Here's a quick demo I did of my 100 watt HRM Today. Just picked this amp up a couple of weeks ago so still dialing it in. Playing through a custom Fusco 2x12 speaker cab loaded with Celestion G12 65s. Recording was done with a single Sure SM 57. Using a TC Electronic reverb pedal and an Alesis Nanoverb for delay which is also managing the makeup gain through the effects loop. Backing track picked off YouTube. Couple of clams in there but...