M2Tech, of Pisa, Italy, has introduced the Nash MC/MM Phono Preamplifier.

The M2Tech Nash has four inputs: phono MC, phono MM, line1 and line2. Each phono input is dedicated to a different kind of pickup. Phono MC input allows for setting MC step-up gain (3dB to 30dB) and input impedance (10 Ohms to 1 kOhms, continuously). Phono MM input allows for choosing input resistance (15 kOhms or 47 kOhms) and capacitance (0pF, 100pF, 220pF and 470pF, plus any combination of the basic values).

M2Tech told us: “The Line inputs act as “bypass” to allow two line level sources (a CD player, a tuner, a reel tape recorder or whatever) to take advantage of the same amplifier’s input the Nash is hooked to. This is basically conceived for the Young MkIII, which only has one analogue input, but it may be useful with every amplifier, especially when the Nash is hooked to a power amplifier with input level control”

.They went on to explain further: “Why have two different inputs for MC and MM? Because this way the first switch on the signal path  is after the MC step-up, therefore on a higher level than the tiny micro Volts delivered by an MC pickup. Moreover, the user can connect two cartridges to the Nash at the same time: one MC and one MM or high output MC, or two MC, one of which through an external step-up. When it comes to phono, the gain is like good food: never enough. Almost all phono stages deliver output voltages between 500mV and 1V, that is the voltage obtained applying the standards 40-46dB gain to an MM signal. As generally more gain means more noise, designers choose a trade-off between noise and output voltage. This means that in a system in which a turntable and a CD player, a DAC or a streamer are the main sources, the user needs to adjust volume every time he switches from the turntable to the DAC and vice versa. The Nash is designed to deliver 2.5V when driven by a standard 5mV outputs MM pickup with great noise performance. The MM gain can be set to 55dB, 60dB or 65dB, to accommodate pickups with output voltages 1mV to 5mV or more. This wide range or values relates to MM pickups, moving iron and moving flux pickups and medium/high output MC pickups. The MC gain can be set 3dB to 30dB, leading to a total MC gain of 58dB to 95dB! That’s enough for every cartridge around.”

“The Nash has a display showing all current settings, plus an IR remote control, plus includes a Bluetooth BLE module that allows the user to control it thanks to the app for both Android and iPhone/iPad. The Nash is based on a discrete components opamp design. Six such circuits are used, with slight differences between MC step-up, MM first stage and MM second stage. Multiple paralleled low-noise FET’s were used to keep noise at a minimum. The RIAA equalizer is passive: this choice was dictated by the desire to have a consistent performance on transients and a good distortion figure all the way from 20Hz to 20kHz and beyond. Of course, no low-noise circuit delivers what it promises when the supply is noisy. For this reason, M2Tech engineers designed a very low noise power supply, using premium low-noise integrated regulators for the MM stages and a specially designed ultra-low-noise discrete components dual regulator for the MC step-up. To keep noise low, the OLED display was modified, disabling its on-board boost converter for display polarisation and driving it with the input 15V”.



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