I went on Friday... made some notes, but I don't need to share all those.
Biggest disappointment was that Grant Fidelity wasn't there, though that was not a surprise... see their website for further info. I think this is the 3rd time time I've been to the Montreal show, and on the 2 previous shows, I spent a lot of time with Ian, etc., in the Grant Fidelity room - very generous with his/their time, informative, good sound, and products that are closer to my budget than most of what I see in Montreal. All the best, Ian.
For this year's show & my ears, there was again everything from really good to ok, and I'm not going to rhyme off the "usual suspects". However, two rooms that stood out for me on this occasion (perhaps partly because I wasn't familiar with the names/reputation) were Gershman Acoustics (room 2413 per the guidebook) and High Water Sound (room 1221).
I don't recall source & electronics in the Gershman room; it's all about their speakers.
l'm pretty sure I actually bypassed the High Water room because it looked like "more of the same" & you can't necessarily stop to listen to everything, but my friend pulled me back. Certainly not a low-budget system, but I found that the noteworthy component was the Horning speaker - it looked unassuming, but I really liked that sound.
Finally, I would add that there were a couple of rooms devoted to headphone systems, which allowed me to make some comparisons. I was able to do that last year as well, but this year's "rooms" were a little better organized & laid out.
After post #3, I realized that since a lot of DIYaudio members are probably not going to the Montreal show, I probably should have posted my "review" on some other website... not really in the DIY direction.
However, to try to partially "correct" that error, I should mention that the Horning Eufrodite speaker (mentioned above) was probably closer to DIY concepts than many of the box speakers that were at the show. It uses a Lowther DX55 wideband + cone tweeter + bass drivers in something of a high sensitivity horn design. I haven't done enough research to explain it properly, but thought this much was worth sharing.