Meizu mBlu/Lifeme Hifi Audio DAC (Pro) / JCally JM6 (Pro) / other Conexant CX31993 dongles

[abm0]

Continuing from this off-topic: https://audiosciencereview.com/foru...-c-phone-dongle-dac-review.10423/post-1602180
... so we don't mess up the Meizu Hifi (Cirrus Logic + OPA) topic any more than we have to with this discussion of the CX+MAX alternatives.

Just to make this a more meaningful thread-starting post, here's some already posted opinions on what the device is / can do:

JCally JM6 Pro that I was talking about above is also a CX31993+MAX97220, and it's got mushy/veiled upper treble immediately apparent when A/B-ing vs. FiiO BTR3

It takes busy tracks to hear it, it's otherwise fine for most music. I've seen someone else report the same lack of treble detail vs. the iBasso DC02, specifically on busy tracks.

I own the JM6 Pro, as well as the Apple dongle and an ancient LeEco one from '16. In comparison to last two the JM6 Pro doesn't sound veiled at all.

I'd scratch the two CX31993 off the list. 1Vrms output and worse distortion and noise than the 9$ Apple dongle. Impressively low power consumption though.

https://web.archive.org/web/2023052...m/contact/donglemadness/cx-pro-audio-cx31993/

And some notes on what it's not:

the "pro" version in your link (CX31993+MAX97220) has nothing to do with the unit measured in this thread, that has CS43131+OPA1622 and is out of production for a long time.

The mblu HiFi (cx31993) is limited to 1Vrms, has more distortion and noise than the Apple A2049, but is still in production.
The Meizu HiFi (cs43131) can output 2Vrms, has very low distortion and noise, but is out of production and no longer available.

the key word there is "mBlu". If you see mBlu or Lifeme it's the Conexant-centric design, doesn't matter if it also says Meizu and Hifi in the name. They're trying to make people believe it's the same as the highly acclaimed CS chip one.

Also, about this finding:

you can get the JM6 Pro and only pay 15-17 USD. My main suspicion is the price difference is just to get more money from people who think the mBlu is the old "Meizu Hifi DAC", but I guess there could be minor differences in implementation as well, if they maybe... put in some EM noise protection in the mBlu? That's the real glaring fault of the JM6 Pro

It turns out that was also due to incomplete insertion of the 3.5mm jack into the JCally's female connector. Looks like it comes with a pretty stiff tip connector inside, that has to develop some flexibility first in order to allow the full click-into-place insertion. Then everything connects fine, all the terminals match, you get stereo sound and microphone signal (can't take any dongle seriously without a microphone connection as their first job was always to replace the lost 3.5mm connector on smartphones), and there's none of that horrible EM noise I was hearing earlier.

So the JCally should really be a much cheaper alternative to the mBlu/Lifeme dongles trying to pass themseves off as CS+OPA "Meizu Hifi" dongles.