Experience unparalleled musicality with the Sutherland Little Loco Mk2 phono preamplifier. This innovative transimpedance design uses current input for stunning clarity, spacious soundstages, and effortless dynamics. Perfect for audiophiles seeking a next-level listening experience, the Little Loco Mk2 eliminates loading adjustments and special wiring concerns, delivering pure sonic performance with moving coil cartridges.

DESIGN PHILOSOPHY

You may have noticed a new kind of phono preamp design on the market—usually referred to as ‘current input’. Until recently, this approach has been very much in the background. But, listeners and reviewers are now giving it some serious consideration. And many love what they hear.

The Sutherland little LOCO is Ron Sutherlands realization of this approach. From the first moments of listening, the musicality is stunning—spacious, effortless & full.

It is “good to go” with no special concerns on turntable signal wiring.The original little LOCO had an essentially balanced input signal requirement. The signal came in on both the RCA center pin and the RCA shell. There was a strict requirement that the RCA shell float above ground.The newly designed Mk2 transimpedance input stage is now single ended. The signal comes in on the RCA center pin. The RCA shell is at ground level.

The little LOCO Mk2 presents a virtual short as the cartridge load. Instead of voltage being the input parameter, it is the current generated by the cartridge that conveys musical content. The endless worry about finding the ‘best’ load value is obviated.The cartridge must be the moving coil type. Those with low output will be embraced. Not compatible with moving magnet or moving iron or step-up-transformers.Thanks to the new little LOCO Mk2 circuit, the shell of the RCA input jack is now at ground. There are no special TT cable requirements.

Place the little LOCO Mk2 near the turntable. The turntable signal is applied to the two centrally located RCA jacks on the back panel. Often there is a ground wire coming from the turntable. Connect it to the grounding screw in the center of the back panel. The output of the little LOCO Mk2 goes to a line-level input on your preamp or integrated amplifier.Load SettingsThere are no loading adjustments in the little LOCO Mk2. Your cartridge will see a load of zero Ohms. The input signal will be the current your cartridge produces into that virtual short. No need to worry about or fuss around with loading choices.

Gain Settings: Your little LOCO Mk2 is factory-set to medium gain. That should work very well in most situations. The usual concerns about cartridge output voltage do not apply here. Cartridges of varied output voltage specs tend to supply about the same level of drive current into a short. i.e. higher output voltages usually have an associated higher internal resistance. Lower output voltages usually have an associated lower internal resistance.If your particular situation would benefit from a gain adjustment, you can change it. Inside, on the red circuit board, you will see movable shunts for gain setting. From the factory, they are set to MED GAIN. You can boost the output voltage by 6dB when the shunts are moved to HIGH GAIN. You can reduce the output voltage by 6dB when the shunts are moved to LOW GAIN.

Specifications:

• Size:
• 17” wide, 13” deep, 2” high
• Shipping Box: 22” wide, 17” deep, 9” high
• Weight
• Unit Weight: 15lbs
• Shipping Weight: 18lbs
• Operating Voltage Requirements:
• 105 — 125 VAC, 10 watts
• 210 — 250 VAC units are available on special order
• Note: operating voltage is NOT universal and cannot be field modified.
• Warranty: 5 years parts and labor. Transferable. Only valid for units that have not been modified or abused.

What is Transimpedance Amplification?

A transimpedance phono stage is a moving‑coil phono preamp that works as a current‑to‑voltage converter: it takes the cartridge’s output current and converts it directly into a voltage, with gain set by a feedback resistor (the “transimpedance”), rather than amplifying the cartridge as a voltage source into a load.
Core definition

    In circuit terms, it is a transimpedance amplifier (TIA) optimized for MC cartridges: an op‑amp (or discrete equivalent) with a large feedback resistor that produces an output Vout≈Iin×RfVout≈Iin×Rf.

    The cartridge “sees” a virtual short at the input (very low input impedance), so its current is determined almost entirely by groove modulation and its own coil resistance, not by an external load resistor.

How that differs from voltage-mode phono

    Conventional phono stages are voltage amplifiers: the cartridge drives some load impedance (often 100 Ω or more for MC) and the stage multiplies the resulting voltage.

    A transimpedance phono stage instead assumes the cartridge behaves as a current source and directly converts that current to voltage, functioning somewhat like an active electronic replacement for an MC step‑up transformer.

Cartridge compatibility aspect

    Because the input is essentially a short, these stages are only appropriate for low‑impedance, low‑output MC cartridges; high‑impedance or MM/MI types are a poor match and can be overloaded or simply not operate correctly.

    Within their intended range, they can provide high bandwidth and low‑noise operation, which is why this configuration is attractive for very low‑level MC signals.