Pro-Ject
Pro-Ject MC Step Up Box S3
Best transformer for audiophiles pairing moving coil cartridges with existing preamps.
The Pro-Ject MC Step Up Box S3 is a high-quality step-up transformer designed to bridge the gap between a moving coil turntable and a moving magnet phono preamp. It features a custom-wound transformer with mu-metal shielding and a fully passive signal path, ensuring extremely low noise and minimal distortion. The dual-mono design maximizes channel separation, while switchable cartridge impedance, gold-plated RCA connectors, and an interference-resistant solid aluminum chassis enhance performance. To extract the best sound from your MC-equipped turntable, pair the MC Step Up Box S3 with a high-end MM phono preamp and rediscover your vinyl collection like never before.
$399.37
Owner Satisfaction
4.5
/ 5
Category Rank
378
/ 474
#378 in Phono Preamps
Price vs Category Average
-94%
Below average
Preamp Type
Passive Step-up Transformer
/ Passive Step-up Transformer
Who it's for
- Audiophiles seeking deeper detail and dynamic range from vinyl
- Vinyl enthusiasts upgrading to MC cartridges on MM-only systems
- Listeners demanding precise electrical matching for peak cartridge performance
Who should skip it
- Minimalists wanting to avoid extra components and added costs
- Users with limited power outlets or cable management constraints
- Casual listeners preferring a simple, plug-and-play audio experience
Performance breakdown
Signal Integrity
Passive design ensures an exceptionally clean and noise-free signal path.
Channel Separation
Dual-mono architecture delivers a wide and precise stereo soundstage.
Cartridge Compatibility
Switchable impedance settings accommodate a broad range of MC cartridges.
Build Quality
Solid aluminum chassis provides excellent shielding and long-term durability.
Frequency Response
Wide bandwidth captures subtle nuances across the entire audible spectrum.
Connectivity Reliability
Gold-plated RCA connectors ensure consistent and stable signal transfer.
Key Specs
Preamp Type
Passive Step-up Transformer
Analog Inputs
1 x Dual RCA Phono (MC)
Analog Outputs
1 x Dual RCA Phono
Frequency Response
10Hz-55kHz (±1dB)
Dimensions
8.11" W x 2.55" H x 6.45" D
Weight
2.07 lbs
Manufacturer Part Number
9120129860383
Features
- Custom-wound transformer with mu-metal shielding for superior sound quality.
- Fully passive signal path for extremely low noise and distortion.
- Dual-mono design for maximum channel separation.
- Switchable input impedance to accommodate various MC cartridges.
- High-quality gold-plated RCA connectors for reliable signal transfer.
- Interference-resistant solid aluminum chassis for durability and performance.
- Designed to enhance the performance of MC cartridges when used with MM phono preamps.
What customers say
Customers consistently praise the Pro Ject MC Step Up Box S3 for its remarkable impact on sound quality. Many reviewers highlight a significant improvement in clarity, detail, and dynamic range when integrating this unit into their vinyl playback systems. Users often express surprise at the enhanced performance, noting a richer, more engaging listening experience. The consensus points to its exceptional ability to elevate the audio output from moving coil cartridges, making it a highly regarded component for audiophiles seeking noticeable sonic upgrades without a prohibitive cost. Its contribution to a refined soundstage and musicality is frequently mentioned.
Know before you buy
This device acts as a bridge between a moving coil (MC) turntable and a standard moving magnet (MM) phono preamp. It uses a transformer to boost the low-output signal of an MC cartridge to a level that an MM preamp can process effectively.
No, the MC Step Up Box S3 features a fully passive signal path. It does not require electricity, which helps eliminate potential noise and interference from power sources.
The unit features switchable input impedance, allowing you to match the transformer to the specific requirements of your MC cartridge. You should check your cartridge's technical specifications to ensure they align with the selectable settings on the device.
The dual-mono construction separates the left and right channels entirely. This design minimizes crosstalk and maximizes channel separation, resulting in a more precise and expansive soundstage.
Mu-metal is a specialized alloy used to shield the internal transformer from external electromagnetic interference. This ensures that the delicate signal from your turntable remains clean and free from hum or background noise.
No, this is a step-up transformer, not a phono preamp. It must be connected between your turntable and an MM phono preamp, which then connects to your amplifier or receiver.
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