Real class-AB discrete transistor amplifiers made small. 45 watts into 4 Ω; 25 watts into 8 Ω. With rugged 15 amp 200 watt output transistors the Proprius drives even the most difficult of speakers.
With volume controls that go all the way, these power amps can be driven by a separate preamp by parking the volume at full — or their own volume controls can be used in a minimalst system driven by a fixed output source.
As a stereo pair the volume controls can be used to balance the stereo image if there’s no balance control anywhere else.
Bi-amping, tri-amping, and surround sound will benefit by using the Proprius volume controls, allowing you to easily adjust the tonal balance and/or audio image placement.
Simple (and Smart) Design
-Power amps don’t have to be brutish – they can be neat and compact as the Proprius shows – and at only 20.5 cm deep by 5.5 cm high by 10.5 cm wide, the Proprius is definitely neat and compact.
-It doesn’t overheat even when used for long intervals at maximum output.
-Easy to connect and get up and running, the Proprius can be used with “single-ended” and “balanced” sources using the same single input XLR socket (left).
-Connect power supply to the “48V” connector – both signal and power connectors are locking – and attach the speaker cable: the speaker terminals accept 4mm plugs; 8mm spades; or bare wire to 4mm diameter.
-The Proprius amplifiers can be used free-standing wherever you want, or mounted on the back of speakers, making them into “powered monitors” using the supplied mounting kit.
Reliability
Intelligent remote power supply can detect when things are getting out of hand when it immediately shuts down and restarts when the problem goes away. But that’s not going to be during normal listening.




- Power output (rms) measured 26 Watts into 8 Ohms; 45.5 Watts into 4 Ohms (ref 1% THD+N at 1kHz)
- Power bandwidth at rated power into 8 Ohms 10Hz – 47kHz (-3dB), 20Hz – 25kHz (-1dB)
- Power bandwidth at rated power into 4 Ohms 12Hz – 40kHz (-3dB)
- Total harmonic distortion and noise at 8 Ohms 100Hz: 0.043%; 1kHz: 0.047%; 5kHz: 0.061%; 10kHz: 0.085%; 20kHz: 0.125%
- Total harmonic distortion and noise at 4 Ohms 100Hz: 0.066%; 1kHz: 0.071%; 5kHz: 0.094%; 10kHz: 0.129%; 20kHz: 0.181%
- Signal to noise ratio in dB “A-weighted”: 87dB; 22Hz-22kHz “Q-pk”: 80dB
- Bias type Class Ab; Bias current: 60mA (approx.)
- Input sensitivity for rated output 575mV rms
- Short circuit protection Fuse and power supply shut-down (short circuits should be avoided to prevent component stresses)
- Fuse F2A 5mm x 20mm (glass “quick-blow” fuse rated at 2A)
- Power supply 48V DC, 120 Watt – self adjusting to AC mains 100V – 240V, 47 – 63 Hz; IEC cord supplied
- Size (approx.) Amp W105 x H55 x D205 mm; Power supply W65 H40 D170 mm
Specifications subject to alteration without notice in keeping with our continuous improvement policy.







