The author developed a DIY measurement system to evaluate the Musical Fidelity M1 turntable, which features an SME M2-9 tonearm. The setup aims to analyze speed accuracy, wow, flutter, and drive errors using digital tools rather than traditional hardware meters.
The measurement chain consists of a Soviet test record, a cartridge, a phono stage, a Creative Sound Blaster G3 USB audio interface, and the WFGUI software. The author also created a custom browser-based viewer to analyze raw data files generated by the software.
The Musical Fidelity M1, introduced in 2004, utilizes a belt-drive system with a brushless DC motor and optical speed feedback. The turntable features a two-tier acrylic chassis, an inverted main bearing, and a platter weighing 5.75 kg, with a total unit weight of approximately 21.7 kg.
Initial tests of the measurement chain using a 3150 Hz tone showed high stability. When playing a local 3150 Hz WAV file, the system recorded 0.0000% RMS, confirming that the measurement channel does not introduce significant wow or flutter before testing the turntable itself.
The author notes that the WFGUI software performs demodulation by measuring the duration of each signal half-period. The raw data is saved in a DAT format, which records the half-period error in tenths of a nanosecond, allowing for detailed post-processing analysis.
