SPL Phonos Duo Phono Preamplifier

MM & MC Cartridge Compatibility

The Phonos Duo supports both Moving Magnet (MM) and Moving Coil (MC) cartridge systems, making it a truly versatile phono preamplifier whatever your turntable setup.

Moving Magnet (MM)

Moving Magnet cartridges generate voltage by moving a magnet between copper coils. To achieve the best possible frequency and phase response, the Phonos Duo offers six selectable capacitance settings — 12 pF, 47 pF, 100 pF, 150 pF, 220 pF and 330 pF — allowing precise matching to your cartridge.

Moving Coil (MC)

Moving Coil cartridges work in the opposite way — the magnets are fixed and the coils move between them. This lower-mass design allows for faster, more precise stylus movement, bringing out the finest nuances in your records. Because MC cartridges output an extremely low voltage, noise-free amplification is critical. The Phonos Duo rises to the challenge with up to 70 dB of gain — among the most powerful available for MC systems — delivered via SPL's 120V VOLTAiR technology for ultra-low noise, linear and phase-accurate amplification. Six impedance settings are available: 20Ω, 50Ω, 100Ω, 220Ω, 500Ω and 1kΩ.

Which Should You Choose?

Moving Coil systems are widely regarded as the more audiophile choice, offering greater precision and detail retrieval due to their lower mass. Moving Magnet cartridges are more robust and typically more affordable — and modern MM designs using neodymium magnets can rival many MC systems in accuracy. Whichever you choose, the Phonos Duo is perfectly equipped to get the very best from it.

Balanced & Unbalanced Connectivity

The Phonos Duo offers two pairs of stereo inputs and outputs — one balanced pair via XLR and one unbalanced pair via RCA. Switching between inputs is straightforward via the INPUT switch on the front panel, while the output signal is always present simultaneously at both outputs regardless of which input is selected.

Gold-plated RCA sockets handle turntable connection and line output to a preamplifier such as the Director Mk2 or Elector. A dedicated ground connection accepts either a clamped or plugged ground lead via banana plug socket. A rear-panel GND LIFT switch isolates internal ground from housing ground to eliminate troublesome ground loops when needed.

Gain Control

Three levels of pre-amplification cover every system. Low position delivers +30 dB for MM and +50 dB for MC — ideal for standard hi-fi devices. Med adds a further 10 dB (MM +40 dB / MC +60 dB), while High reaches MM +50 dB and MC +70 dB, bringing output levels in line with modern DA converters.

Subsonic Filter

The mechanical rumble of a turntable's drive mechanism can be exaggerated by the high bass gain inherent in RIAA equalisation. The Phonos Duo includes a switchable subsonic filter to cleanly remove this rumble and keep your low end tight and articulate.

Mono, Mute & Power

A MONO switch sums the stereo input signal to mono — ideal when playing mono records with a mono cartridge. A MUTE switch silences all outputs instantly, and the ON switch powers the unit simply and reliably.

RIAA Equalisation

RIAA equalisation has been the global standard for vinyl recording and playback since 1954. During the cutting of a record, bass frequencies are reduced by up to 20 dB to save groove space and extend playing time, while high frequencies are boosted by up to 25 dB to improve the signal-to-noise ratio. During playback, the Phonos Duo applies the exact inverse curve, restoring a perfectly linear frequency response.

Douglas Self RIAA Design

The RIAA equalisation circuit is built on the recommendations of renowned British audio engineer Douglas Self — holder of honorary degrees from Cambridge University and a lecturer in psychoacoustics at the University of Sussex. His approach uses many small capacitors rather than fewer large ones, enabling faster charge and discharge cycles for superior resolution and impulse response. Only audiophile-grade Styroflex capacitors are used throughout.

We endeavour to despatch same day for orders placed up to 1pm on available stock items (items with stock message "Usually dispatched within 24 hours"). Please remember to check with us first for a physical stock check if next day delivery is important to you. Any items with stock message "Usually dispatched within 72 hours" are items that we do not hold in stock but order in from the importer or manufacturer as soon as a customer order is received. Occasionally these may be delayed beyond 72 hours due to importer/manufacturer stock levels but we will inform you as soon as we can if this is the case.

UK Orders

We despatch the bulk of our UK mainland items on a 24 hour service – Free of Charge.  Non Mainland locations - Isle of Man, Isle of Wight, the Scilly Isles, the Scottish highlands and Islands, the Channel Islands and Northern Ireland may take a day or so longer and are not Free of Charge. Smaller items are delivered using Royal Mail 24 or special delivery. Larger items are delivered using a courier service such as DPD or UPS.

International Orders:

Due to the nature of our products and brand restrictions we are only able to send certain items internationally. Smaller items are delivered using Royal Mail Small Packets Airmail with International Tracked and/or Signed depending on value of item and availability of the service. Larger International shipments are sent by insured and tracked services using UPS. If there are any delays due to specific customs regulations, etc, you will be contacted by Hifisound or by the courier with a request for any further information required. Customs duties can apply for shipments to any countries outside of the UK depending on where the product you have bought is made. Customers are responsible for all taxes and duties incurred when the items enter their country.

Collect in Store or Home Install

At the request of the manufacturer some items cannot be supplied by mail order but you can click and buy them and then elect to collect them from our store or arrange a home install (if applicable). Applicable items clearly state that they are Collect in store or home install. Once ordered you will receive a message prompting you to contact us by phone or email to arrange for us to deliver and install or to reserve and collect from our store at your convenience, you will also be advised of the delivery time / stock availability as not all Home install / collect in store items are held in stock.