HiFi Rose RA280 Integrated Amp

By: Ed Selley [hi-fi+ Issue 236]

On occasions, audio companies can positively delight in subverting expectations, and the device you see here is a magnificent example of the practice. If you were to consider the range of HiFi Rose streamers, most recently the RS130 streaming transport that featured in issue 230, you might assume that any matching amplifier would feature extensive connectivity and be firmly into the ‘smart’ category of amp we’ve seen in increasing numbers over the last decade.

One look at the RA280 should have you questioning such assumptions, and a more involved glance at the back panel will be enough to let you know you would be very far off the mark. Regarding operation and connectivity, the RA280 is undoubtedly a very ‘trad’ piece of kit—almost the complete opposite of the streamers. However, HiFi Rose has channelled their willingness to do things a little differently into the actual amplifier section itself.

No shortage of power

Like the larger (and more visually spectacular) RA180, the RA280 is a class D design. There are only two channels here as opposed to the four in larger amps, but there’s no shortage of power, with 250 watts available in 8 ohms. The genuinely exciting part of this section is lurking in the output. HiFi Rose has sought to deal with the notional ‘dead time’ when the circuit switches between states. The RA280 incorporates ultra-high-speed gallium nitride FETs intended to reduce this notional dead time to an irreducible minimum. I will note at this point that, by an astonishing coincidence, the most vocal proponents of the dead time concept happen to make other types of amplifiers, but it shows some interesting thinking on the part of HiFi Rose.

Neither is this the only interesting material choice in play. A switching power supply is used, and this can swing 2.5kW for dynamic peaks as required. It uses silicone carbide FETs to further beef up the means of delivery. Something potentially handy is that this is a switching PSU with universal voltage. Even if the means by which the RA280 works are notionally conventional, the details by which it does it are not.

This amplifier section connects a preamp stage that uses a conventional volume pot with an actual start and finish point. This has a very pleasant weight and feel, but it’s only fair to point out that, with the balanced input especially, the minimum position on the volume control is not actually silent, and the mute function will be needed to ensure that the amp actually stops making noise. It’s unclear if this is deliberate, but this is my first time seeing it.