Recently, I have been enamored with the Mojo2 - for its affordability and ability to be transformed using my kit of products. I have addressed isolation from RF noise on signal (SRC-DX chain with RF-STOP Signal), radiated (DAC-WRAP and environmental) and suggestions for power. Mojo2 has an excellent, low-noise internal battery design but users have reported sonic improvements with external 5VDC power - which required disconnection of the battery to force Mojo2 into desktop mode.
As my readers know, LFP batteries rule in my system: they have near zero electrochemical discharge noise and only nominal added BMS (battery monitoring system) RF noise, which can be RF-STOP filtered. I appreciate that batteries have a nominal impedance/ESR - which is a frequency dependent ("AC") resistance - typically measured at 100kHz. Ideally, you want a power supply with zero ESR and zero RF noise.
Hence my development of PURE-DC which uses a bank of supercapacitors and all-analog control module. This design has the lowest RF noise and the lowest ESR possible. PURE-DC is available in 5V and 12V models. The 5V model has an ESR of 0.23 mΩ; the 12V model has an ESR of 0.92 mΩ. Consider these numbers in comparison to ESR of capacitors present in commodity power supplies:
- Nichicon Electrolytic : 8-30mΩ
- MLCC (Multilayer Ceramic Caps) : 20mΩ
- Tantalum : 800mΩ to 1200mΩ
Even LDO voltage regulators have an ESR of about 1000mΩ.
So if you have a Mojo2 and would like to hear it at its absolute best, you need to consider a PURE-DC supply.