SPL Phonos duo Phono RIAA Preamplifier for Pro Audio and Hi-Fi - Red

The SPL Phonos duo expands the established SPL phono preamplifier Phonos with a pair of balanced stereo inputs and outputs. Phonos duo is thus even more versatile. Whether moving magnet (MM) or moving coil (MC) cartridge systems – the SPL VOLTAiR technology and the RIAA filter in the legendary Douglas-Self design form the fundament for an outstanding phono sound.

MOVING MAGNET AND MOVING COIL

Moving magnet cartridges generate a voltage by moving a magnet between copper coils. In order to achieve the best possible linearity of the frequency and phase response, the capacitance is modified to adjust the cartridge. Phonos duo offers six different capacities for this adjustment: 12 pF, 47 pF, 100 pF, 150 pF, 220 pF und 330pF.

The moving coil cartridge is also a small electromagnetic generator. However, the magnets are firmly anchored – and the coils move between the magnets. This concept is exactly the opposite of the moving magnet cartridge. Consequently, it is not the capacitance but the impedance that is the decisive parameter in matching the cartridge. Phonos duo offers six different impedances for this adjustment: 20 ohms, 50 ohms, 100 ohms, 220 ohms, 500 ohms and 1 kohm.

FREE CHOICE – BALANCED OR UNBALANCED

Phonos duo offers two pairs of stereo inputs and outputs. A pair of balanced inputs and outputs with XLR inputs and outputs and a pair of unbalanced inputs and outputs with RCA connectors. The INPUT switch on the front of the Phonos duo can be used to switch between the two stereo inputs. The output signal is always present in parallel at both output – regardless of the selected input.

CONNECTIONS

Gold-plated RCA sockets are available for connecting the turntable and for outputting to a preamplifier such as the Director Mk2 or the Elector. A ground connection for the turntable is designed as banana plug socket. The ground lead can be either clamped or plugged in. Phonos duo also features a switch on the rear panel labeled GND LIFT. This ground lift function can be used to eliminate ground loops by isolating the internal ground from the housing ground when the switch is pressed.

PERFECT LEVEL

The GAIN switch can be used to set the preamplification. There are three values to choose from. In the “Low” position, the amplification for MM systems is +30 dB and for MC systems +50 dB. This is ideal in combination with standard HiFi devices that operate with a reference level of -10 dBV In switch position “Med”, the amplification is increased by 10 dB (MM = +40 dB, MC = +60 dB). If the switch is in the “High” position, the gain is increased by a further 10 dB (MM = +50 dB, MC = +70 dB). This means that the output level is approximately as loud as that of modern DA converters at a reference level of 0 dBfs = 15 dBu.

The rumbling of the turntable‘s drive mechanism is amplified by the high amplification of the bass range due to RIAA equalization in playback (see RIAA equalization). The Phonos duo offers a switchable subsonic filter to remove this rumble.

The MONO switch can be used to select whether the stereo input signal should be output as a regular stereo signal or summed to mono (switch in the On position). This is useful, for example, when using a mono system to play mono records.

VOLTAIR TECHNOLOGY

The 120V technology is SPL's reference technology. The 120V technology is unique in the world. It operates at a DC voltage of 120 volts. This is four times that of IC-based semiconductor op-amps. In SPL's Professional Fidelity series, this unsurpassed technology is referred to as VOLTAiR technology.

SPL PHONOS DUO FEATURES:

• Phono preamplifier with balanced stereo input and outputs
• Compatible with moving magnet (MM) or moving coil (MC) cartridge systems
• GAIN switch can be used to set the preamplification between three settings
• Switchable subsonic filter to remove rumble
• MONO switch can be used to select whether the stereo input signal should be output as a regular stereo signal or summed to mono
• 120V VOLTAiR reference technology