Hello All,
Encouraged by the positive experiences posted here, I've thought I'll workaround the corporal ripoff network too and ordered an EasyLander 2500mAh battery for the Mojo from AliExpress (
https://www.aliexpress.com/item/1005002524097664.html ).
Everything went smoothly, 1 month later i happily received the battery for around 15€ shipped to Austria.
After replacing it - full of hope and excitement - i was frankly disappointed by how much the sound has worsened compared to using the weary (but still good for ~4 hours) original battery. I could not believe that nobody noticed the difference before. My
subjective findings:
Overall definition and dimensionality degraded into a bit fuzzy and more distant presentation. The background became less 'black', dynamics (micro/macro) dropped significantly ('prat' / slam / body disappeared). The oh-so-famous 'timing' or 'coherence' was also lost. The precise transient edges became worst than those of a quality on-board soundcard. The end result is a flat, chaos-like, uninvolving sound. The Mojo has lost its mojo. (Long live Austin Powers
.) I gave it a 2nd chance, charged it full but the sound remained the same. It lasted 7.5 hours on USB input which i consider good (enough).
To my horror removing the EasyLander's connector from the socket seemed impossible, but eventually somehow managed it with the main board still in one piece.
I remember reading about the importance of power supply here and there, and did some googling on the differences of Li-Ion and Li-Po batteries. (Although the specifications on Ali state the EasyLander to be Li-Po, i
believe it's a Li-Ion, given the low price. Li-Po is significantly more expensive to manufacture.) It turns out that Li-Po is bettered in everything by Li-Ion but peak performance (voltage drop under load, fast reaction, max instantaneous current delivery), which can well account for the differences.
As I realized i can't live with it like this, i ordered an original replacement battery from the authorized Chord service in Germany, and bam!, my loved Mojo was back. This made me 90€ lighter, 60 for the battery, 30 for the postage (the guys in the Chord service can only post it as a DHL packet if one wants tracking & insurance, phew). The original battery i received is 8 years old, but so far works as expected. The test to see how long does it last is in progress as i write.
To be fair, I use the Mojo as a DAC connected to a HK680 amp which drives Mission 767s, so my bad experience with the EasyLander could be easily caused by the 22KOhm input impedance of the amp compared to a couple hundred Ohms headphones' impedance. Since
i rarely use it with cans, i haven't done any tests with them.
Of course, no offense is intended in any way against anyone. This is a subjective experience which i thought is worth to share.