NuPrime AMG PRA Preamplifier, Grey

The NuPrime AMG PRA is a purely analogue preamplifier that controls volume in 92 fine steps and comes with four-stage bass control as well as switchable phase control.

In short: this is the control centre between your sources and the power amp – no digital detour, but a volume control that still resolves cleanly even in whisper-quiet territory. Few knobs, a lot of effect.

Why the AMG PRA?

A good preamp doesn't draw attention to itself – it adds nothing and leaves nothing out. That's exactly what the AMG PRA aims for: separate circuit boards keep interference away, the two-stage gain (High/Low) adapts it to different power amps, and the switchable phase control keeps the signal correctly polarised.

The 92-step volume control works so finely that quiet levels don't lose resolution or balance – a point where cheaper preamps often struggle.

What you get

On the input side, the AMG PRA accepts balanced XLR and unbalanced RCA sources, each with 1 MΩ input impedance. On the output side, 2 V is available via RCA and 4 V balanced – enough level for practically any power amplifier.

The special feature is the four-stage "Active Low Frequency and Harmonic Gain" control: a targeted bass boost that lets you compensate for small speakers or a difficult room, without immediately reaching for an equaliser. On top of that comes finely graduated loudness compensation for quiet listening sessions.

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Who is the AMG PRA for?

For anyone who deliberately builds their chain from preamp and power amp and wants an honest, analogue preamp with a few useful adjustments. Ideal as a partner to the AMG power amps ONE and STA.

Honestly: if you expect a built-in DAC, streaming, or phono stage, this isn't it – the AMG PRA is purely analogue and focuses on preamplification. That very reduction is its advantage, but you should want it.

Our verdict

The AMG PRA is an unassuming, cleanly built preamp that pays off in the right combination. HiFi-Advice and Totally Wired describe the AMG PRA and AMG STA as a sonically and visually coherent duo – the preamp's full, powerful tone complements the power amp perfectly. The Absolute Sound included the AMG PRA in its 2024 Buyer's Guide as one of the biggest high-end bargains. We at HD Zürisee in Wädenswil appreciate how calm and neutral it goes about its work.

Technical data

• Design: purely analogue preamplifier (no DAC)
• Volume control: 92 steps (step 92 = 0 dB, input = output)
• Bass control: 4-stage (Active Low Frequency and Harmonic Gain)
• Phase: switchable phase inversion
• Gain: 2-stage – 10.10 dB (High) / 6.44 dB (Low); voltage gain 3.2 / 2.1
• Inputs: balanced XLR and RCA, 1 MΩ each (nominal input 8 V XLR / 4 V line)
• Rated output voltage: 2 V (RCA) / 4 V (XLR) @ 100 Ω
• Frequency response: 10 Hz – 200 kHz (+0 / -0.1 dB)
• THD: 0.008 %
• Signal-to-noise ratio: 95 dB
• Loudness compensation: 2.2 dB (125 Hz) / 4.5 dB (100 Hz) / 5.3 dB (75 Hz)
• Construction: separate circuit boards, 15 mm aluminium front panel, CNC-milled chassis
• Control: remote control with programmable remote code
• Dimensions (W × H × D): 235 × 55 × 300 mm
• Weight: 3.5 kg
• Colour: Grey
• Warranty: 2 years

Frequently asked questions

Is the NuPrime AMG PRA an analogue preamplifier?
Yes, the AMG PRA is a purely analogue preamplifier with no built-in DAC. It accepts analogue sources via XLR and RCA, controls volume in 92 fine steps, and passes the signal on to your power amp. Digital sources need a DAC in front of it.

What does the AMG PRA's bass control do?
The four-stage Active Low Frequency control lets you specifically boost the bass range. This helps compensate for small speakers or a difficult room, without bending the rest of the sound. You choose the stage to match your speakers and placement.

Which power amp suits the AMG PRA?
The AMG PRA is tuned to the NuPrime AMG power amps – the AMG ONE monoblock or the AMG STA stereo amp. Thanks to switchable phase control and two-stage gain, though, it also suits many other power amps. We're happy to help you work out which combination fits.

Does the AMG PRA have balanced XLR connections?
Yes. The AMG PRA handles balanced XLR as well as unbalanced RCA signals, each with 1 MΩ input impedance. On the output side it delivers 2 V via RCA and 4 V balanced. That lets it integrate cleanly into differently built chains.

Why buy the NuPrime AMG PRA at HD Zürisee?
Because a preamp is the heart of the chain and needs to suit the power amp and speakers. We advise you on the right combination, check the levels, and take care of setup and service with our own technician. Call, write, or come to Wädenswil.

Goes well with

To let the AMG PRA show its strength, we've put together the right categories:

• The matching power amplifiers
• A digital source in front: DAC
• Playback via streamer
• Plus the speakers
• More from the series: NuPrime