OK, I have a well burned in pair of IMR Dark Matter and Bass Cannon 2023. I can only talk about the ones I received. I know from experience that there can be unit variability with some IMR IEMs, as my initial DM was totally different to the replacement I have now....which I
. Bass on both the DM and BC mirrors what Bob says about them on his IMR Acoustics web pages. Potent.
I now have the 7Hz Legato, which after a sneak listen, I put on initial burn in for 5 hours, just to loosen up the drivers. The Legato comes with the same very large case that the Salnotes Dioko came with. Just a different color, burgundy. A great case, not for carrying the IEM, but for storing dongles, BT dongles and adapters and other various bits and pieces. I immediately put a KBear 7N OCC Copper 4.4mm cable on. The package comes with various Acoustune tips and I put the Yellow, Large AET 07 on and hooked it up to my iFi Go Blu LDAC receiver listening through Amazon HD.
The 7Hz project was a specialized project to create an in ear IEM which was reminiscent of old, large bassy, HiFi speakers. Has the project succeeded in that? Absolutely yes. The bass is the biggest I have heard on any IEM. On first listen it was a bit soft and fuzzy, but after the 5 hour burn in both the softness and fuzz have totally disappeared. A couple of YouTubers had said the mids were recessed. That is a 'fetch all' generalistic statement. For non bass-head tunes the mids are positionally correct. For tracks like Ambitionz Az A Ridah the mids have enough body and position relative to the massive bass lines and are plenty fine . On the bassy, New Model Army war rock, vocals are perfectly placed relative to drums and bass. Drum hits certainly have wallop and impact. Highs do not have any 'technical' nature but they have good clarity and reasonable extension. There is way more capability in these than the epithet 'Bass-head'. I have been to many live concerts and these remind me of those massive stage speakers and thumping bass lines like 'Enjoy the Silence' live, from Depeche Mode. Definitely a specialist IEM which are pointless for those who do not like impact bass and rumble. If you like big bass these are perfect and mids and highs are clean, clear and good. For $100 a bit of a specialist bargain, for producing a feeling like you are at a live concert/gig.