Phasemation T-550 MC Step-Up Transformer

Passive MC step-up transformer with 26 dB gain, balanced phono input, and rigid copper-plated chassis

Suited to cartridges with an output impedance of between 1.5 and 40 ohms, the T-550 is a robustly engineered step-up transformer designed to reveal the full musicality of low-output MC cartridges. It introduces a balanced phono input for improved noise rejection, making it ideal for high-performance analog systems.

The T-550’s chassis follows Phasemation’s flagship design concepts, with a 10 mm slanted aluminum face, a 1.2 mm copper-plated chassis, and a 1.6 mm copper-plated cover. The transformer itself is floated on damping rubber to suppress vibration, and magnetic shielding reduces external induction hum. This is a passive, low-noise design built for uncompromised playback.

At its core is Phasemation’s original split-winding transformer architecture: low-loss, ultra-thick copper windings on a large EI core made of 78% permalloy. This yields wide-band frequency and phase characteristics, excellent bass linearity, and a clear, spacious sound image across the audible range. Gain is fixed at 26 dB.

Compared to the T-320, the T-550 adds a balanced XLR input, heavier copper-plated chassis panels, transformer suspension, and magnetic shielding, offering greater noise rejection and vibration control.

Who Needs a SUT?

If you have a low-output moving coil cartridge, a step-up transformer allows you to passively increase the output of the cartridge, letting you use a moving magnet input on a phonostage, which has far less active gain, and therefore far less chance to magnify noise. A SUT has to be very carefully matched to your cartridge, so make sure you talk to our analog team before buying one.

Specifications

Optimum Cartridge Output Impedance: 1.5–40 Ω

Load Impedance: 47 kΩ

Gain: 26 dB

Frequency Response (+/-2 dB): 10 Hz–50 kHz

Input / Output Terminals: Gold-plated RCA and XLR (input), gold-plated RCA (output)

Dimensions (WHD): 6.85" x 3.54" x 6.81" (174 x 90 x 173 mm)

Weight: 4.63 lb. (2.1 kg)