SPL Phonos DUO - MC/MM Phono Preamp

The RIAA Phono Preamplifier – Doubly Good
The SPL Phonos duo Phono Preamplifier extends the renowned
SPL phono preamplifier with a pair of balanced stereo inputs and outputs. This makes the Phonos Duo even more versatile.

Whether you use a moving magnet (MM) or moving coil (MC) cartridge,
SPL VOLTAiR technology and RIAA equalization filter in the legendary
Douglas Self designs form the basis for exceptional phono sound.

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An eye-catching design – a must
Externally, the SPL Phonos duo Phono preamplifier fits perfectly into the SPL HiFi line
Professional Fidelity – and it is, of course, available in three basic colors: black, red or silver.

MM and MC
There are two systems of turntable cartridges:

Moving Magnet (MM) and Moving Coil (MC).

Moving Magnet
Moving magnet cartridges generate a voltage through the movement of a magnet between copper coils. To achieve the best possible linearity of frequency and phase response, the capacitance is adjusted to match the cartridge. Phonos Duo offers six different capacitances for this pairing:

12 pF, 47 pF, 100 pF, 150 pF, 220 pF and 330 pF.

Moving Coil
The moving coil cartridge is also a small electromagnetic generator. However, the magnets are firmly anchored, and the coils move between them. The principle is exactly the opposite of that of the moving magnet cartridge. Therefore, the decisive parameter for cartridge matching is not capacitance, but impedance. Phonos duo offers six different impedances for this matching:

20 ohm, 50 ohm, 100 ohm, 220 ohm, 500 ohm and 1 kOhm.

MC or MM?
Moving coil systems are generally considered more suitable for audiophiles,
because their reduced mass allows for faster and therefore more precise tracking.
They extract the finest nuances from the groove, so to speak.

The output voltage of a moving coil system is extremely low, only a few hundred microvolts, and is therefore more sensitive to noise and induced hum.
This very low output voltage must be amplified with extremely low noise and therefore requires a very sophisticated preamplifier.

Phonos duo offers one of the most powerful
phono preamplifiers for moving coil systems, with preamplification up to 70 dB. Thanks to 120V SPL technology,
Phonos duo amplifies with extremely low noise, linearity and phase locking.

Moving coil cartridges have very low inductance and impedance.

This means that the effects of cable capacitance (from the cartridge to the preamplifier) ​​are less significant. Impedance, however, is the relevant parameter here and can therefore be adjusted across six values ​​in the Phonos duo. Manufacturers specify the cartridge impedances. These values ​​must be adhered to as closely as possible.

Moving magnet cartridges, on the other hand, are robust and often less expensive.

The high mass of the moving magnets, however, creates greater inertia,
This results in less precise groove tracking. However, modern moving magnet systems also use neodymium magnets, which have significantly lower mass.

These moving magnet systems can even compete with some moving coil systems in terms of tracking accuracy.

Capacitance plays a crucial role with moving magnet heads.

This means that the effects of cable capacitance (from the cartridge to the preamplifier) ​​cannot be ignored. The capacitance for moving magnet cartridges can therefore be set to six values ​​on the Phonos Duo and optimally adapted to the system.

Suggestion:
If you're unsure which capacitance corresponds to the cartridge's, you can simply switch the capacitances on the Phonos Duo. As the high-frequency range increases, the capacitance is lower than the cartridge's. If the high-frequency range decreases again, the capacitance is higher than the cartridge's.

Free choice: balanced or unbalanced
Phonos Duo offers two pairs of stereo inputs and outputs. One pair of balanced inputs and outputs.
with XLR inputs and outputs and a pair of unbalanced inputs and outputs with RCA jacks.

The INPUT switch on the front panel of the Phonos Duo can be used to switch between the two stereo inputs.

The output signal is always present in parallel on both output pairs, regardless of the input pair selected.

Connections
Gold-plated RCA and XLR connectors are available for connection
to the turntable and for forwarding to a preamplifier such as the
Director Mk2 or the Elector.

A ground connection for the turntable
It is designed as a gold-plated terminal
where you can connect the ground wire