Summary of Musiland Monitor 01 MINI MODS
Why Musiland 01-Mini?
Because it is the cheapest model (I paid US$ 60), and easiest to get to the I2S lines.
SUMMARY OF MODS (all easy to do)
- Enable SPDIF: link (The circuitry is already in the board, but requires installing a resistor to enable the spdif output. When you load the driver and the Musiland Mini is connected, you will see a SPDIF option)
- Tap I2S lines: link (avoid a conversion step)
- Disable DC-DC power supplies: link (cleaner data/clock lines). Before and after clock trace.
- Increase linear regulator capacitors: link (better power regulation)
- Added a (5V) power indicator LED (There are better ways to install the LED. For example, remove C60, install a surface mount resistor (500-1K ohm) on the power line leading to C60, and cut the power to the DC switching supplies near C12; then install LED in C60)
- (Planned) Add some ferrites to the USB power (remove potential high frequency noise/EMI from the laptop)
- (Not planned) You could replace the on-board regulators with low noise types like the LT1963, but that’s a lot more work.
- (Not planned) You could also replace the 24MHz crystal with a 24 MHz clock (but I’m not sure how much of an improvement that would be).
CLOCK AND JITTER
Clock generation in the Musiland device is explained here. I guess what leads some people to prefer the Hiface device over the Musiland device is the way the audio clocks are derived.
In the Musiland device, the 24.576MHz and 22.5792MHz clocks are derived by the DCM (digital clock managers) in the fpga by doing integer multiplication and division on a 24MHz clock. In addition, the frequencies are derived by cascading two DCMs.
The Hiface instead uses two clocks: 24.576MHz and 22.5792MHz and presumably these clocks must also be divided (integer division) by the fpga’s DCMs in order to get the right frequency for I2S and SPDIF (I am only guessing that the clocks are divided by the fpga as I don’t know for sure. I only know that the SPDIF frequency is much smaller -and thus you need to divide the frequency).
The resultant clock jitter in both devices is therefore the initial jitter of the incoming clock plus the jitter added from the DCMs. In theory, the Hiface implementation will result in lower jitter because the incoming clock is potentially of lower jitter and the frequency derivation is simpler (the argument here is that if one DCM is used instead of cascading two DCMs, the jitter is lower – I don’t know for sure how the Hiface is implemented, but for Musiland, there is evidence that the clocks are derived by cascading two DCMs)
Drivers can be found here:
- Official Release: Musiland Driver Downloads (look for USB). Site is in Chinese. The English language site points to a very old driver
- Officially released drivers: Musiland historical driver directory. Look for MlCyMON
- Latest driver (likely Beta): Musiland latest driver directory. Look for MlCyMON
- All device drivers here: Tam’sAudio Old and new Musiland Monitor Drivers. This directory is maintained by a retailer of Musiland products. All the drivers that have been released are here
- Installing the driver and using ASIO: http://bbs.musiland.com.cn/viewthread.php?tid=4813&extra=page%3D2 (Musiland forum entry. Must have account. Use google toolbar to translate)
- Firmware upgrade: http://coolfungadget.com/musiland/Update_Firmware.html
UPDATE: See here