The Power Box RS2 Amp is the optional linear power supply for the Amp Box RS2 power amplifier: it replaces the stock switching adaptor and offers two output voltages, 35 V for cooler running and 45 V for up to 25% more power.
Power Box RS2 Amp: 35 or 45 V for the power amp
The voltage selector lets you decide how the amplifier should run. Pro-Ject recommends 35 V, above all with 4 ohm loudspeakers: the amplifier draws less and runs cooler, which helps when it sits in a closed cabinet where little air circulates. At 45 V the Amp Box RS2 gains up to 25% in output, but amplifier and supply then need a spot with good ventilation. Either way, the Amp Box RS2 has protection that switches it off by itself before heat can do any harm.
At the core of the unit is an audio-grade toroidal transformer, isolated from the mains and screened with copper foil, far more generous than a standard adaptor: it accounts for much of the 4.7 kg weight. Low output impedance and 40,000 µF of filtering on low-ESR capacitors let it meet the current demands of the amplifier; according to Pro-Ject, soundstage, background silence and detail all gain.
Rectification is followed by precise voltage regulation, a soft start limits current at switch-on, and the low-noise parts include surge protection. The lead that links it to the Amp Box RS2 comes with the supply. The enclosure is rigid aluminium, chosen for screening too, and the unit is manufactured in Europe.
Specifications
- Type: linear power supply, non-switching
- Component powered: Pro-Ject Amp Box RS2 power amplifier
- Output voltage: ±35 V or ±45 V, set by a switch
- Output current: 4 A
- Mains input: 115 V / 230 V AC
- Filter capacitance: 40,000 µF on capacitors with low ESR
- Transformer: audio-grade toroid, copper-foil screen
- Switch-on: gradual soft-start circuit
- Supplied accessories: link lead for the Amp Box RS2
- Size: 206 mm wide, 71 mm high, 209 mm deep
- Weight: 4.7 kg
- Finishes: black, silver
