JCALLY JM20 Headphone Dongle Review

[solderdude]

I have the jm20 that I sometimes use with my hd600 and wondering if the max or another dongle would make a difference. When I go louder it almost feels like it's running out of gas but could be placebo. It also warms up more than I expected. I haven't done a side by side with other gear I have.. this is my portable setup.

The JM20 (just like almost all other dongles) is rather limited in output voltage 2V = 13mW in 300ohm meaning the HD600 can only reach 109dB peak SPL = between 90 and 100dB average depending on the music which means moderately loud at best.
So while the sound will stay clean up to the max level it can reach you may still be left wanting, especially when you add 5 dB of bass (which isn't a bad idea for the HD600).
In that case you can deduct that 5dB and will end up with average levels between 85 and 95dB SPL.

 

[bequietjk]

Recently I noticed my dongle getting extremely hot to the touch after 20 minutes or so and the audio seems to be clipping at that heat level. Audio fidelity of course is insanely good and would love to keep it but I would rather spend more on something that won't heat up so much and either spend more or take a hit on audio fidelity. Any recommendations?

 

[staticV3]

Recently I noticed my dongle getting extremely hot to the touch after 20 minutes or so and the audio seems to be clipping at that heat level. Audio fidelity of course is insanely good and would love to keep it but I would rather spend more on something that won't heat up so much and either spend more or take a hit on audio fidelity. Any recommendations?

Apple headphone adapter

Consumes one third as much power as the JM20.

 

[nanook]

Since I seem to have lost my JM20 I'm interested as well.
Do you mean this one?

Review: Apple vs Google USB-C Headphone Adapters

This is a review, detailed measurements and comparison of Apple's USB-C adapter to the current and last version of Google Pixel headphone adapters. The Apple adapter costs just $9 including one day shipping for free. The Google dongle costs $12. Not that any of these are large by any stretch...

www.audiosciencereview.com

Or is there a new revision out in the meantime?

 

[staticV3]

Since I seem to have lost my JM20 I'm interested as well.
Do you mean this one?

Review: Apple vs Google USB-C Headphone Adapters

This is a review, detailed measurements and comparison of Apple's USB-C adapter to the current and last version of Google Pixel headphone adapters. The Apple adapter costs just $9 including one day shipping for free. The Google dongle costs $12. Not that any of these are large by any stretch...

www.audiosciencereview.com

Or is there a new revision out in the meantime?

There is a new revision out, actually as the product code was changed from
MU7E2ZM/A (Europe) / MU7E2AM/A (USA) to
MW2Q3ZM/A (Europe) / MW2Q3AM/A (USA)

Though AFAIK the model number has remained the same at A2155 (Europe) / A2049 (USA).

Whether the revision brought any changes to performance, functionality, or power consumption with it, I don't know.