Audes ST-500 DC Power Conditioner

Audes ST-500DC power conditioner – Compact Mains Filtering for Source Components

The Audes ST-500DC power conditioner is a compact mains filter with integrated DC blocker, developed by Estonian manufacturer Audes for use with sensitive digital and analogue source components. At the heart of the Audes ST-500DC power conditioner is a 500 VA balanced toroidal transformer — designed entirely in-house — that galvanically isolates connected equipment from the mains. Only clean, stable power reaches your source components.

Ideal for Source Components and Smaller Systems

The ST-500DC is the entry-level model in the Audes ST-series and is specifically designed for components with lower current demands. These include streamers, DACs, preamplifiers, phono stages and network switches. With four CEE 7/3 sockets and a compact footprint, the ST-500DC fits effortlessly into any listening room or desktop setup.

Effective Filtering of Mains Pollution

The toroidal transformer is designed to filter mains noise via controlled leakage inductance and capacitance. The cut-off frequency is set at 800 Hz — well above musically relevant frequencies. Interference from dimmers, switch-mode power supplies and solar panels is almost entirely removed. The output voltage is symmetrical with respect to an artificial centre tap connected to the earth contacts of each socket.

DC Blocker and Protection Circuits

The integrated DC blocker protects the transformer from harmful DC components present on the mains supply. This significantly reduces mechanical hum in transformers of connected components. The ST-500DC also features a fuse for overcurrent protection and thermal protection that shuts down at 90 °C and reconnects automatically at 75 °C.

Key Specifications

• Type: Power conditioner with integrated DC blocker
• Power rating: 500 VA
• Inlet: 10 A, IEC C14
• Outlets: 4 × CEE 7/3 (16 A / 250 VAC)
• Transformer: Balanced toroidal, 230 VAC / 115 + 115 VAC
• Filter principle: Controlled leakage inductance and capacitance
• Thermal protection: Shutdown at 90 °C, auto-reconnect at 75 °C
• Dimensions: 215 × 162 × 270 mm
• Weight: 11.5 kg
• Origin: Estonia

Frequently Asked Questions

Which components is the Audes ST-500DC power conditioner suited to?

The ST-500DC is designed for source components with lower current demands: streamers, DACs, preamplifiers, phono stages and network switches. For power amplifiers or larger complete systems, the ST-1500DC or ST-3000DC power conditioners are more appropriate.

How does the ST-500DC differ from the larger Audes power conditioners?

The ST-500DC has four outlets and a 500 VA power rating — more compact and lighter than the ST-1500DC and ST-3000DC. The transformer architecture and filter principles are comparable, but the headroom is matched to source components rather than power amplifiers.

Does the ST-500DC work without an earth connection?

Yes. The symmetrical transformer construction ensures the power conditioner operates correctly without an earth connection. Mains plug polarity makes no difference either.