Guys. I had an early delivery. Instead of April 15th it was delivered yesterday.
So far me experience has been good. After testing it and making sure it works I proceeded to open it:
On the inside we find two boards: one is the power supply which seems of a good quality. It does not show any indication of the OEM, it says SMSL01POWER
It has a MBR30200FCT (30 Amp Schottky Barrier Rectifier 200Volts) and a Lonten LSD65R280HT (Lonten N-channel 650V, 15A, 0.28Ω LonFET TM Power MOSFET)
Now the actual amplifier board:
The main components are:
JL AS218P0A950-2504. I could not find anything about this chip. But it looks like the BT and USB receiver
We also have 2 ST072C opamps, but I traced those down and they don't seems to affect the audio coming from RCA imputs. They might be used 1 for amplifiying the signal coming from the receiver chip, and also used as a low filter for the SW out.
We have a DC-DC step down buck converter for 5V supply and a MAX660 Switched Capacitor Voltage Coverter
Next we have the OPA1678 opamp to feed the Merus MA12720 chip
Gefore the opamp we have the 3710 2007U which seems to be a Relay switch for the multiple inputs (RCA, USB or BT)
The RCA input path is traced to those 2 input capacitors, then go into the relay switch and then to the to pot which is detachable and connect with the ribbon cable. Then it goes to the opamp and continues until it reaches the main chip.
The case is made of plastic:
The bottom is a metallic plate and it is used as heatsink for the Merus chip by connecting to an aluminum shim or adapter. I removed it and replaced the thermal paste for a better non conductive TIM.
Now, my so far analysis. This is a very nice and small amp. I'm not interested on its USB or BT features (I know they won't be the best ones), I already have a much better DAC for that use. But using the RCA inputs the sound is very good.
Let me tell you about my setup:
I use a computer USB and TV optical into a SMSL SU-6, then it goes into a SMSL SH-6 Headamp/preamp. I also use two Tube Preamps (FX Audio Tube 01 and FX Audio Tube 03 both heavily modified (Tubes, resistors and capacitors on both and opamps on the Tube 03 and fed by a Linear Power Supply). I was using the original black board with nice audio components Aiyima A04, the only mod was to change the opamps to OPA1656 on adapters. That's a good amp, even better than the Aiyima A07. I can confirm that the A04 has more power than the A100, but the sound on the SMSL is better, is more melodic and has more micro details and resolution. It is weird but somehow having three power states compared to two as the usual Class D amps produces a more linear sound, closer to class A, A/B. Even thou the A100 provided up to 5W into 8ohms with 0.005% THD, and up to 11W with 0.01%THD it is more than enough. We don't usually use more than 4-5W on a small room, it gives plenty of volume with speaker the 88 dB/mW and above sensitivity. If I want louder then I use my HIFIMAN HE400SE headphones.
I use a switch for multiple speaker outputs connected to a JVC SX-F50 towers, a Jamo C93 II and a Sony SS-SC5. Additionally I have a Mirage Omni S8 subwoofer which I can now connect directly from the Amplifier instead of one of the Tube preamps using RCA Y cables.
I don't really know how good this amp will measure, but for my ears is a step forward coming from the Aiyima A04. It sounds nice even streaming Amazon Music (not unlimited or HD).
With HiRes files it sounds wonderful. I know I can't compare this to high-end amps but it is enough for me. I might stay like this for a while.
