What is it?

The AAL – USB Power Isolator 10W is a compact, galvanically isolated 5V/2A USB power supply designed to reduce electrical noise and interference reaching USB-powered equipment.

It uses an industrial-grade Cosel MGS100505 isolated DC/DC converter to electrically separate the USB power source from the connected device, providing up to 10W of regulated 5V power.

Main features:

• 5V / 2A regulated output (10W maximum)
• Galvanically isolated power supply
• Industrial-grade Cosel MGS100505 DC/DC converter
• USB-C power input / USB-A power output
• 4-layer PCB with 2 oz outer copper
• Separate input and output ground domains
• Input and output filtering and protection
• Switchable USB Dedicated Charging Port (DCP) signature
• Compact enclosure
• Designed, hand-assembled and individually tested by AAL – Analog Audio Lab

IMPORTANT: POWER ONLY – NO USB DATA TRANSMISSION.

This device isolates the USB power supply only. It does not transmit USB audio, MIDI or any other USB data.

Compatible with devices powered by a standard 5V USB supply (up to 2A). A switchable DCP (Dedicated Charging Port) signature is provided for devices that require charging-port detection. USB Power Delivery (PD) negotiation is not supported.

Why did you make it?

USB power is convenient, but it isn't always clean.

Computers, switching power supplies, chargers and other USB sources can introduce unwanted electrical interference into sensitive equipment.

As an electronics engineer and musician with extensive experience in studio recording and live sound, I've encountered these problems in real-world audio setups.

I wanted to develop a compact, reliable and practical solution that would isolate the power supply itself, without unnecessary complexity or exaggerated audiophile claims.

The goal was straightforward: provide clean, galvanically isolated 5V power for devices that need it, with enough current capacity for more demanding USB-powered equipment.

The result is the AAL USB Power Isolator 10W.

What makes it special?

1. Industrial-grade isolation

At the heart of the design is the Cosel MGS100505, a 10W isolated DC/DC converter from an established industrial power supply manufacturer.

Rather than relying on an inexpensive, uncharacterized converter module, the design uses a documented component intended for reliable power conversion.

2. Designed for real-world loads

With up to 2A available at 5V, the isolator can power a wider range of USB devices than low-power USB isolators limited to a few hundred milliamps.

3. Carefully designed PCB

The custom 4-layer PCB features 2 oz outer copper, separated ground domains, input/output filtering and dedicated protection circuitry.

4. Independently tested — with measurable results

An independent beta tester carried out an extensive evaluation using FFT analysis, direct power measurements, audio loopback tests and oscilloscope observations.

The results showed:

• Significant reduction of discrete interference components from several USB power sources
• Effective interference reduction at both 1A and 1.5A loads
• No measurable audio degradation in the tested loopback configuration
• Oscilloscope observations consistent with the FFT results

The improvements depend on the original power source and operating conditions. An already clean supply may show little practical benefit.

A detailed illustrated beta-test report is available upon request.

5. No magic, just engineering

This is not a device designed to artificially enhance audio quality.

Its purpose is to address a specific electrical problem: interference carried through USB power.

When that problem exists, galvanic isolation can make a measurable difference. When it doesn't, audible improvements should not be expected.

Who did it?

Designed, hand-assembled and individually tested in France by AAL — Analog Audio Lab.

Practical electronics designed to solve real-world problems.

analog.audio.lab@gmail.com