Arcam has been through a turbulent few years. In 2012 it became a subsidiary of Canadian conglomerate JAM Industries whose main fields are pro audio, music, and lighting. Five years later Arcam was bought by Harman to join brands including Revel, Mark Levinson, and JBL. So in under a decade, what was once little old A&R Cambridge has become part of a global empire that’s ultimately owned by Samsung. So, it’s no wonder that this integrated amplifier looks and operates rather differently from the Arcam Alphas of yesteryear.
In truth, the SA20 doesn’t look that different. It costs a lot more than a 1990s Arcam Alpha of course, but what has really changed is that there is a fairly powerful processor at the heart of this amplifier. I’ll start from the top: the SA20 is the bigger of two integrated amps in Arcam’s latest HDA range, sitting alongside the near identical SA10, but offering 90 Watts/channel rather than the 50W of the more affordable offering. There is also the CDS50 CD/SACD and network player in the range but that’s it, no DACs or dedicated streamers yet (they are in the popular rSeries though). As with Arcam’s two-channel FMJ amplifiers, the SA20 has a Class G hybrid power amp section, which operates in Class A up to 12 Watts then switches in an additional power supply that produces Class B for situations that require greater power. The difference between this and a classic Class A/B design is that there is a transition area where both power supplies are operating which is claimed to eliminate the crossover distortion that typifies the latter. It’s worth noting that both power supplies are linear and that Class G is not a new thing; the theory dates back nearly fifty years, but it is complicated to implement successfully.
The SA20 has an on-board digital to analogue converter that runs a 32-bit Sabre DAC chip and has three inputs. Oddly given its 2019, it eschews USB, but includes Toslink and coaxial S/PDIF connections marked BD, AV, and SAT. Arcam is of the opinion that USB connections are not so much in demand and cite the positive commercial response to the CDS50 as a sign that disc spinning is making a comeback. Unusually there is a network socket for Ethernet cable and I had hoped that it might be possible to stream to this but it turns out to be for the purpose of IP control, such as you have in multi-room/custom install situations. There are three single-ended analogue inputs (marked CD, PVR, and STB) alongside an aux input on a minijack socket on the front panel. I’m surprised that the processor doesn’t offer the option to change input names given that they are displayed on a dot matrix (they are however printed on the buttons of both amp and remote). I note that one input can be set for use by an AV processor where the Arcam provides the front L and R channels in a home cinema set up. Finally, there’s also an MM phono input.