Amplifier & Preamplifier


150 Watt Amplifier, Class A to 50 watts

The R-1.5 amplifier is designed to drive any loudspeaker, producing warm, “tube like” sound quality. It has been constructed with premium parts, including metal film resistors and film capacitors, reinforcing Usher’s reputation for high-quality manufacturing. High-power bipolar transistors, designed by Motorola, can handle sophisticated power and current requirements. And its massive AC power transformer works with a high-capacitive filtering system for the purest sound. Other features include Burrow-Brown OPA2134P Sond Plus Series op amps, bridging switch for mono block operation, terminals that accept both banana plugs and spades, optional balanced inputs and large handles on the front and rear panel.


Amplifiers available in silver brushed aluminum

8 Ohm/20Hz-20kHz: 150W(ch)
4 Ohm/20Hz-20kHz: 260W(ch)
damping factor: >175 (single ended)
circumgyration: >40V / uS
power supply (4 Ohm): >16A
transient power supply: >75A
S/N ratio: 100 dB
frequency (20Hz-20kHz): +/- 0.1dB
weight: 37 kgs
dimension (w x d x h ): 48 cm x 48 cm x 22.5 cm

shipping weight: 40 kgs /pc
shipping box (w x d x h): 60 cm x 59 cm x 35 cm

$2750.00 / ea


Pre-Amplifier with phono input

P-307 is the control center of today’s high end sound systems. Its two main functions are source selection and volume control. Every effort has been made to keep P-307 as accurate as possible.

To avoid unwanted interactions with adjacent source components, P-307 uses high-quality relays and switching designs to ensure that every source is intact. Thus all sources remain separate from one another and from the power amplifier and cables.

In the digital age, analog preamplifiers remain the most reliable and neutral-sounding component of controlling volume. P-307 uses a superior attenuator
that offers a neutral sonic performance.

Since AC power supply generates noise, P-307’s power supply is housed in a separate chassis. Thus P-307’s audio circuits are exposed only to quiet, regulated DC power and the audio signals itself.


power consumption: 7W maximum
main voltage: 100V,120V, 200V, 230V or 240V AC@50/60Hz
inputs: 7 stereo single-ended(RCA)
1 stereo single-ended(RCA)phono
outputs: 2 stereo single-ended(RCA)
gain: 14.3 dB
S/N: 105 dB
input overload: 2.34V rms
input impedance: 47k Ohm
outputs impedance: 120 Ohm
maximum output (MAIN outputs): 15.3V rms
frequency Response: 10Hz~100kHz
weight: 4kgs
overall dimensions (w x d x h): 43 cm x 28.8 cm x 7.9 cm

shipping weight: 5 kgs /pc
shipping box (w x d x h): 56 cm x 35 cm x 16 cm

$2,964.00 / ea