This new Ortofon ST-7 MC transformer is the most affordable step-up on offer from the Danish manufacturer. It is built in Japan by Ortofon's Japanese subsidiary. It has a small metal housing with a striking black aluminium front panel, and rests on four feet designed to dampen mechanical vibrations.
The rear panel boasts two pairs of excellent RCA sockets and a copper ground plug. The internal wiring is made up of very high quality conductors. The ST-7 transformer uses coils with a brand new internal structure, which preserves an excellent dynamic range and an excellent response in the higher frequencies. Unlike other step-ups, which often produce a dull sound, the Ortofon ST-7 boasts two coils – one per channel – which are individually shielded. This significantly reduces noise while simultaneously boosting the stereo effect.
The ST-7 transformer was specifically designed with Ortofon MC cartridges in mind, and particularly the brand’s Quintet and SPU Classic ranges. However, it is also compatible with many other MC cartridges, by Ortofon and other brands, as long as they don’t require a load of more than around 60-80 Ohms. That being said, we got impressive results with a cartridge with a recommended load of 100 Ohms.
The sound quality is very spacious, with a highly realistic sound stage. The timbre quality is also worth a special mention. It goes without saying that these results were strongly related to the top quality MM phono preamplifier we used to set it up.
If your amplifier has an excellent MM phono preamp and you're thinking about buying a moving coil cartridge, the Ortofon ST-7 transformer is the one for you! Exceptional value for money. Franck
Frequency response: 15-45kHz (+0 dB, 2.5 dB)
Gain: 24 dB at 1 kHz
Recommended cartridge impedance: 2-60 Ohms
Recommended load: 47 Kohms/200 pF
Dimensions: 122 x 43.5 X 102 mm
Weight: 790 g