Audio Power Supplies Buying Guide

A power supply feeds clean, stable DC or AC power to audio and AV equipment such as microphones, network devices, preamps and controllers. A poor supply can add hum and noise or cause intermittent faults. This guide explains how to choose power supplies for studios, installations and live rigs.

Voltage and current

Match the output voltage to the equipment's requirement exactly: 12 V DC, 24 V DC, 48 V DC and others are common, and supplying the wrong voltage can damage a device. The supply must deliver at least the current the device draws, and it is wise to choose a unit with 20 to 30 per cent spare capacity so it runs cool and lasts longer. Power in watts is voltage multiplied by current, so total your devices before choosing.

Heat is the enemy of any power supply. Capacitors age faster when they run hot, so a supply loaded close to its limit in a warm rack will fail sooner than one with spare capacity. In Indian conditions, where ambient temperatures are high for much of the year, allow generous ventilation and avoid stacking supplies directly on top of each other. A little extra capacity at the start is cheap insurance against a mid-event failure.

Polarity and connectors

DC plugs come in various sizes and the centre pin may be positive or negative. Check the polarity symbol on the equipment and the plug dimensions before connecting. Installation supplies often use screw terminals, which are secure and neat in a rack or enclosure.

Regulated, switch-mode and linear

• Switch-mode supplies: efficient, compact and light, and the most common choice for modern equipment
• Linear supplies: bulkier and less efficient but can be very quiet electrically, preferred by some for sensitive analog gear
• Regulation: a regulated supply keeps the output voltage steady as load and mains vary

Low ripple and noise matter for audio. Check the specification for ripple and look for suitable filtering when powering preamps and microphones.

Mains input and protection

In India mains is 230 V, 50 Hz, and supplies should accept this input safely. Mains voltage can be unstable in many areas, so look for a wide input range where possible. Protection against overload, short circuit, over-voltage and overheating is essential. A fuse or automatic reset helps protect connected equipment and the installation.

Phantom power and microphone supplies

Condenser microphones need phantom power, typically 48 V, usually supplied by the mixer or preamp. External phantom power units are useful when the input does not provide it. Check that the supply is stable and low-noise, and that it matches what the microphone requires. Read about preamps and processors to see where phantom power is typically provided.

Rack and installation supplies

Rack-mount supplies can power many devices from one place, with individual outputs fused or protected. In installations, DIN-rail and enclosure supplies are common. Consider cooling, fan noise and mounting, and place supplies where heat can escape. For network devices, check whether power over Ethernet from a switch could do the job instead of separate supplies; see AVB networking for related equipment.

Choosing for your application

Studio

Low-noise supplies for preamps, converters and outboard gear, kept away from signal cables.

Live and touring

Robust, protected supplies and spare units, with secured connectors that will not pull out.

Installed AV

Reliable regulated supplies with headroom, protection and clear labelling for maintenance.

Installation tips

• Keep power supplies physically apart from sensitive audio cables
• Use a mains surge protector or a proper earthing arrangement to protect equipment
• Label each supply with the equipment it feeds
• Keep a spare for critical equipment

Common mistakes to avoid

Most supply faults come from mismatched specifications and poor mains.

• Using a power supply with the right plug but the wrong voltage or polarity
• Choosing a supply with no spare current capacity
• Running a supply in a closed space with no airflow
• Powering sensitive audio gear from a noisy supply and ignoring the hum
• Ignoring poor mains and earthing at the site

Buying power supplies at Shivansh Electronics

Shivansh Electronics, Kolkata, West Bengal, India supplies genuine products only, exactly as the manufacturers build and specify them. Every product page has its specifications, so you can compare models side by side before you decide. Our team can help you shortlist options for your room, venue or project, explain how the specifications apply to your setup and suggest the accessories you will need. Message us on WhatsApp or call us for advice, or visit our showroom in Dhakuria, Kolkata.