Had the M15c for a few days now, listening with B&W P7s (single ended), HD620S and HD600 (single and balanced).
It’s exactly the same size as M15/M15i, with same standard/high gain switch on the side. Internal positioning of some components looks a bit different, and now there’s just one red LED to show it’s connected, not a separate one or two for gain. One bonus is it’s noticeably lighter than M15i, seems the shell material must be less dense, so good when carrying it tethered to a phone.
So how does it sound? Excellent, kind of like a slightly different take on the M15i. It’s an interesting comparison and I think it’s not necessarily a case of M15i or c being better, different people are likely to prefer one or other depending on their tastes.
It’s difficult to choose the right words to describe the differences without the risk of them being over-interpreted, but here goes. 15c has more of a bass emphasis, and that bass has great texture and detail within it. The soundstage can be more central focused, with a slightly smooth tone to instruments, making it seem more ‘wooly’ and less detailed or resolving in a way than the 15i. 15i, in contrast, is more left to right in its presentation, more on a single plane, with a bit more space between instruments. But 15c also has a difference where it sounds like you can hear right down into mix, whereas the 15i presents things more upfront.
It wouldn’t surprise me if some people described the 15i as more clinical and 15c as more organic, but the 15i in itself has a sense of soul and I wouldn’t want to cast it as necessarily ‘clinical’.
Personally I’m preferring the 15c so far. Apart from the usual audiophile suspects of soundstage, bass, mids, treble etc. the 15c wins me over with a real sense of groove. I find myself just wanting to play one more track, then another, just to hear what the 15c does with it, so you know you’ve found the right kind of special for you when that happens
I should also mention the price but don’t want to spoil anything for Questyle in case there’s been some mistake! When I ordered it I thought I might be paying a deposit and would be charged more at the time of shipping, but that never happened. I don’t know what price it will go for overseas, but here I paid less than half of what the M15i is going for. Maybe the dongle market is so competitive, and Questyle has already done all the R&D for the 15/i, that they’re going for the lower price bracket with the 15c.
It’s exactly the same size as M15/M15i, with same standard/high gain switch on the side. Internal positioning of some components looks a bit different, and now there’s just one red LED to show it’s connected, not a separate one or two for gain. One bonus is it’s noticeably lighter than M15i, seems the shell material must be less dense, so good when carrying it tethered to a phone.


So how does it sound? Excellent, kind of like a slightly different take on the M15i. It’s an interesting comparison and I think it’s not necessarily a case of M15i or c being better, different people are likely to prefer one or other depending on their tastes.
It’s difficult to choose the right words to describe the differences without the risk of them being over-interpreted, but here goes. 15c has more of a bass emphasis, and that bass has great texture and detail within it. The soundstage can be more central focused, with a slightly smooth tone to instruments, making it seem more ‘wooly’ and less detailed or resolving in a way than the 15i. 15i, in contrast, is more left to right in its presentation, more on a single plane, with a bit more space between instruments. But 15c also has a difference where it sounds like you can hear right down into mix, whereas the 15i presents things more upfront.
It wouldn’t surprise me if some people described the 15i as more clinical and 15c as more organic, but the 15i in itself has a sense of soul and I wouldn’t want to cast it as necessarily ‘clinical’.
Personally I’m preferring the 15c so far. Apart from the usual audiophile suspects of soundstage, bass, mids, treble etc. the 15c wins me over with a real sense of groove. I find myself just wanting to play one more track, then another, just to hear what the 15c does with it, so you know you’ve found the right kind of special for you when that happens

I should also mention the price but don’t want to spoil anything for Questyle in case there’s been some mistake! When I ordered it I thought I might be paying a deposit and would be charged more at the time of shipping, but that never happened. I don’t know what price it will go for overseas, but here I paid less than half of what the M15i is going for. Maybe the dongle market is so competitive, and Questyle has already done all the R&D for the 15/i, that they’re going for the lower price bracket with the 15c.