I finally took the opportunity today to extensively listen to the 840's. A year or two ago a couple of my co-workers had picked them up, and my initial listen had been positive, but it wasn't until now that I've taken the opportunity to listen to them closely.
In particular I wanted to compare them to my trusty Sony 7506's which have been my work can of choice for years. The Shure's, being clearly influenced by their design, have been on my radar as a possible upgrade at some point should I choose to want to part with the money. So this was a direct back-to-back comparison between these two cans. The source being was iTunes on my Thinkpad T410s, fed via USB to a Corda Move. Nothing super, but perfectly adequate for resolving differences between cans. The 7506's being approximately 5 years old and having Beyer replacement pads, the 840's, as mentioned, 12-18 months old with plenty of time on them.
After some extensive listening, I found this thread, and was relieved to find that at least some of the observations matched mine almost exactly. Specifically on page 123:
The 840s tend to flatten melodies and thus not letting you hear the compositional structure of a piece of work as clearly.
and
This was especially surprising because of the relative bass hump of the Shure's, and their reputation as somewhat bass heavy. That was true on some tracks for me, but on many more delicate or complex pieces, I found that following the bass-line was difficult to near impossible, sometimes it was completely absent. I'd switch back to the Sony's, and nope, it was there clear as a bell to pick out. Back to the Shure's and it was in there somewhere, but I couldn't quite follow it. When the bassline was front and center, then it was full and present (if a little boomy) on the Shure's, but when it was more obscured, it often disappeared altogether. Specifically, on Eric Clapton's Unplugged track #2 Before You Accuse Me someone is keeping time with their foot, but it's only audible as a low frequency resonance. On the Sony's it's clearly there and easy to follow, on the Shure's it's there and then it's gone and I can't really follow it. In the Shure's favor on this track, they provide a bit more of an upfront sound, appropriate to this recording. Yet it also illustrates their other primary weakness in my view, which is a mid-band congestion that makes it difficult to pick out separate instruments.
I first picked this out on Art Blakey and the Jazz Messengers The Complete Blue Note Recordings Disc 5 track 3 Tell It Like It Is. It first showed up as a lack of focus for the Shures. Cymbal strikes that were sharp and definitively placed on the Sony's were muddy and almost as if a veil had been placed in front of the mic on the Shures. The effect was subtle, and on its own, the Shure was engaging and enjoyable, but when directly compared the difference was striking. While the bassline, when the focus, had a bit more punch (see the 'up front' comments from above), the primary impression was congestion where everything was mushed together. When I switched back to the Sony's it was almost a feeling of 'phew' as each instrument again occupied its own space.
All said, I was really astonished by these results. As a big fan of the 7506's, they have certainly been in consideration for an upgrade, with the 840's previously being primary on that list, as they should be all that the 7506's are but more. I guess I've saved myself some money, but it just goes to verify why these have been in heavy rotation for so long. They don't hold up well when directly compared to my best gear, but for durable, all around travel/everyday use, they are still pretty great. I do wish they had the heft of the Shures though. Again, in isolation they seem fine, but handling the two side by side the Shure's are built to a different standard.
