Phono Preamplifiers

Enthusiasts can access a deal of information about the M8x Vinyl through MF’s website and press releases cut ’n pasted by bloggers worldwide! However, what you won’t read elsewhere on the web is this: the simplest way to understand the M8x Vinyl is to see it as a solid-state version of the Nu-Vista Vinyl 2 [HFN Feb ’24] with which it shares the same RIAA eq and balanced gain structure. The key difference between the two units lies in the higher voltage ‘swing’ available to the latter’s tube output stage – 21.9V versus the lower 10.1V offered by the M8x Vinyl. The newer amp’s sub-1ohm output impedance confers some benefit over the Nu-Vista’s <1kohm (bass) output, but that 6.7dB difference in level translates into a similar reduction in input overload headroom on all MM/MC input gain options.

In practice, the M8x Vinyl offers the same eight gain settings – four MM and four MC – as the Nu-Vista Vinyl 2 but the input level that’s tolerated before one or other stage in the preamp clips (~1% THD) is now 103mV, 73mV [black trace, see Graph above], 53mV and 37mV versus 209mV, 151mV [red trace], 110mV and 80mV, respectively, for MM. The input clipping limits for the four MC gain settings are 10.5mV, 7.5mV, 5.4mV and 3.8mV versus 21mV, 16mV, 11.5mV and 8.0mV, respectively. But here’s the good news – MF’s engineers have done their homework – for while the M8x Vinyl has, across its settings, 6.1-6.7dB less headroom than the Nu-Vista Vinyl 2, this still leaves it with ~1dB more than the ~20dB target necessary to accommodate the fiercest of cuts without clipping. So, by a whisker, the M8x Vinyl welcomes all MMs and MCs. PM