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Classic Audio Spartan 15: MM phono stage from Michael Fiedler

Classic Audio Spartan 15
Classic Audio Spartan 15

The British company Classic Audio introduced a new phono stage in the Spartan series – Spartan 15 , which became a logical continuation of the successful two-stage phono stage for working with moving magnet (MM) heads Spartan 10 – the company’s debut model, released in 2021.

Handcrafted in Kent, England, the SPARTAN 15 phono preamp uses Japanese 2068 op-amps specifically matched to the impedance of the MM cartridge, delivering a record-breaking 78dB signal-to-noise ratio for a phono preamp. Very accurate RIAA equalization (to within 0.1 dB) is achieved by using 1% tolerance film capacitors to eliminate the coloration and channel balance issues associated with more common designs.

MM phono stage Classic Audio SPARTAN 15

The SPARTAN 15 phono preamplifier is equipped with a 3rd order infrasonic filter to prevent unpleasant infrasonic intermodulation distortion in speaker systems. The polypropylene film capacitors in the filter are hand-selected during assembly to achieve consistent filter performance without the characteristic low frequency inconsistencies associated with lesser quality filters. There is a switch to mono mode on the front panel, which can significantly reduce noise and distortion when playing monaural recordings.

MM phono stage Classic Audio SPARTAN 15

Like its predecessor, the popular SPARTAN 10 phono preamplifier, it uses an original two-stage amplification circuit to achieve a gain of 110 for a 1 kHz signal (40.8 dB). As a result, it was possible to achieve very low SOI (0.0006%) in the range from 40 Hz to 22 kHz. The input signal can reach 95 mV at 1 kHz without causing overload.

MM phono stage Classic Audio SPARTAN 15

The linear power supply uses highly reliable Panasonic electrolytic capacitors with precision reference diodes and an external transformer, which allows you to reliably isolate the phono circuit from external electromagnetic interference. Using a linear power supply provides much better isolation from the mains than switching power supplies. Also implemented here is a circuit for shutting off the output signal when turning the phono stage on and off, based on a Panasonic relay, which allows you to protect subsequent system components from transient processes.

  MM phono stage Classic Audio SPARTAN 15

The Classic Audio SPARTAN 15 phono preamplifier is housed in a sandblasted anodized aluminum body and is available in black or silver finishes. The new product is already on sale – the phono stage can be ordered directly from the manufacturer. UK RRP £330 . In EU countries, SPARTAN 15 will be offered for 400 euros , and in the US you will have to pay 450 dollars for the new product .

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