MC Step-up Transformer - Ortofon ST-70
The Ortofon ST-70 reserved for the discerning audiophiles and music lovers. The ST-70 combines the fine components along with world-class engineering, for unparalleled sound reproduction.
Starting with high quality Lundahl™ transformers, surrounded by a specialized mu-metal shielding, listeners can be assured that every detail in a complex array of notes is reproduced with utter purity, with freedom from internal and external sources of interference. These two items combined make the ST-70 transformer one of the quietest, most revealing transformers.
Featuring dual mono design, the ST-70 provides discrete circuitry for each channel, resulting in the elimination of crosstalk and possible distortions. This results in cleaner, clearer reproduction with substantially increased stereo imaging. Regardless of the composition being played, the ST-70 expansive stereo separation provides lifelike realism, and accurate tonal balance devoid of coloration.
To further minimize signal degradation and maximize signal flow, the ST-70 has been engineered using high quality industrial grade PCB. Additionally, gold plated RCA jacks with Teflon insulation provide optimal conductivity for use with high quality interconnects. Internally, the unit is assembled with an absolute bare minimum of internal wiring, preserving absolute signal integrity.
The ST-70 applications
The ST-70 maintains compatibility with most Moving Coil cartridges by using internal jumpers to select between two gain/impedance options. This affords audiophiles with broad flexibility while still maintaining a clean aesthetic.
Why use a transformer? Since the output of MC cartridges is low, higher gain is required to utilize it, such as that provided by Step-up moving coil transformers or MC phono preamplifiers. Although both devices provide this requirement, both are fundamentally different in function and in sonic character. This is where Step-up moving coil transformers are frequently seen as superior; they are completely passive and offer exceptional noise performance and sound quality.
Technical data Configuration A:
- Recommended cartridge impedance: 5-50 Ω
- Gain: 24 dB at 1 kHz
- Frequency response: 10 Hz - 100 kHz ± 1 dB
- Recommended: load 47 KΩ // 200 pF
Technical data Configuration B:
- Recommended cartridge impedance: < 10 Ω
- Gain: 30 dB at 1 kHz
- Frequency response: 10 Hz - 80 kHz ± 1 dB
- Recommended load: 47 kΩ / 200 pF
Dimensions and weight
- Dimensions: 58 mm(W) x 135 mm(H) x 150 mm(D)
- Weight: 1.233 kg
Why use a transformer?
Step-Up Transformers (SUT) are a serious option for anyone who owns a Moving Coil (MC) cartridge, one that can significantly improve both the sound quality and sonic character. Quite simply, a good transformer is the best way to audition an MC cartridge with the highest performance possible.
Since the output of MC cartridges is lower than that of a Moving Magnet (MM), higher gain is required to utilize them, such as that provided by SUTs or MC phono preamplifiers. Although both devices provide this requirement, both are fundamentally different in function and in sonic character. This is where SUTs are frequently seen as superior; they are completely passive and offer exceptional noise performance and sound quality.
This is due to the fact that the structure of harmonic and intermodulation distortion is fundamentally different between MC-preamps and SUTs. While an MC pre-amplifier has a constant resistive input impedance, an SUT has an input impedance that is frequency dependent. The harmonic distortion produced by SUTs is highest at the lowest frequencies and drops as the frequency rises, whereas in most MC preamps the distortion increases as the frequency rises. Combined with significantly lower Intermodulation Distortion (IMD), the sound produced with an SUT will be much more open, dynamic, spacious, and natural.