Integrated Amplifiers

If you're an enthusiast with more than one pick-up, and irritated by fiddly DIP switches on the rear of an amp to set MM/MC gain/loading, then you might feel the 404 Reference is less friendly still. To make any changes here you need to unscrew the lid and then also unscrew a metal screening can that hides the optional phono card.

But it's worth the trouble... with MM selected, full gain through the preamp is +58.5dB including +17.3dB for the line stage. In practice, the tape loop provides a better indication of the true MM and MC gain at +41.2dB and +59.2dB, respectively. This translates into MM/MC sensitivities of 8.71mV and 1.1mV, supported by very generous input overload margins of 84mV and 10.5mV (or +24.5dB and +26.4dB headroom re. 5mV and 500µV, respectively). The A-wtd S/N is very wide (noise is low) via MM at 91.1dB (re. 5mV in) and slightly less so at 72.2dB via MC (re. 500µV in) while distortion is vanishingly low at ~0.0002% midband to 0.005%/20kHz [red infill, inset Graph]. The response [black trace] is flat to ±0.1dB from 1kHz-100kHz but bass rolls away from –0.75dB/100Hz to –1.3dB/20Hz. PM