Pre/Power Amplifiers

The review sample came complete with the BluOS module fitted, bringing the total price here to £3898: this seems pretty standard for NAD loan stock, and clearly shows the company is keen to emphasise the integration of even its high-end products into the Bluesound eco-system. And as expected, the combination of the amplifier and the multiroom system proved a very felicitous one, with the amplifier immediately found and under the control of the BluOS app on the budget Android tablet I use as a controller for testing devices of this kind.

Dramatic Dynamics
And the sound, playing files from my usual network storage as well as the odd Tidal Masters track, was every bit what I was expecting from the M32. The balance here is big-boned and rich without ever lacking in agility, and provided you don't push it too far (see below) the amp always sounds clean, open and fast, with excellent rendition of both fine detail and even the largest and most dramatic dynamic swings. In other words, it plays music, and in a highly appealing and convincing manner.

With its BluOS integration the M32 really is a breeze to use, but if that's all you ever do this is a very expensive streaming device, so I soon parked this facility for a while to explore the other inputs on the amp – and quickly reached a few conclusions. One is that getting the impedance selection correct is important, as noted above: set it too high and the top-end gets rather soft and shut-in, while another is that this unusual amplifier has one odd volume characteristic. As PM explains in his Lab Report, this is a digital amp so it 'clips' at 0.0dB – the Spinal Tap 'goes to 11' thing is really not recommended here.

Not that that's a problem, given the hefty power of the amplifier and its plentiful dynamic capability. By the time you get anywhere near the 0dB mark you're already well up into 'exciting' levels and beyond. The other somewhat more notable factor is that the analogue inputs, while reasonable enough, play second fiddle to the crispness and clarity available from the digital inputs that necessarily drive this 'Direct Digital' amplifier, er, directly.

This is especially true when playing hi-res content, which the BluOS module will handle at up to DSD128, even if this is actually processed by the amp's 192kHz/24-bit DAC, which also sets the limit for the USB-B 'computer audio' input. Given that most inputs are going to be digital these days, that's less of a hardship than once it would have been – and the analogue performance can be optimised by selecting 192kHz as the ADC conversion rate, which restores some sparkle to the sound. However, I wouldn't suggest this amp as an optimum choice for a system heavily biased to LP playback, for example.

Real Impetus
When the M32 is good, though, it is very good, exerting fine grip on the speakers with which it's used – which in my case included my original PMC OB1s and the Neat Iota Xplorers. With the lush orchestrations and electronica of Deadmau5's Where's The Drop? set [Mau5trap, via Tidal] the power of the M32 is much in evidence in the big, rich bass, while the cleanness of the string tone shows the openness and detail here. (There is, incidentally, a long story at Wikipedia about the March release of this album solely via Tidal streaming, although other media will be released.)

With more direct rhythm-driven music, such as John Mayall's 1990 album A Sense Of Place [Island 260 637] the warmth of the M32 doesn't stop it powering the bass and drums along with real impetus while bringing out the character of the lead guitar and vocals. Similarly, with jazzers Lake Street Dive's new set Free Yourself Up [Nonesuch 567158; HDTracks 96kHz/24-bit] the level of detail on offer serves this ultra-precise recording very well indeed, keeping the rhythm section good 'n' tight while allowing Rachael Price's remarkable voice full rein. The lushness of 'Musta Been Something' is simply lovely, while the amp isn't caught out when the easy mood of 'Shame, Shame, Shame' kicks down a gear and goes for it.

All of which might suggest the M32 is something of a curate's egg, but that's not quite so: buy it for what it does well, and you'll be delighted, as fortunately its strengths are substantially greater than its limitations.

Hi-Fi News Verdict
Treat its analogue inputs as a 'makeweight' – they're good, but not great – and the M32 is a hugely impressive integrated amplifier, with plenty of power allied to real control and grip, driving hard without losing the plot. Add the BluOS module and you have a superb all-in-one network/computer music solution, combining ease of use with no shortage of focus despite its appealing warmth and weight.