Harley Benton PowerPlant ISO-2 Pro

I’ve been running the Harley Benton PowerPlant ISO-2 Pro on a small rehearsal board for a few weeks, and it’s proven to be a surprisingly capable little power hub - especially for the price. I wanted something compact with genuine isolation so my combination of overdrives, modulation and a digital delay wouldn’t hum or interact, and this unit promised exactly that functionality in a pocket-sized chassis. My aim was straightforward - quiet, stable power for up to eight pedals without breaking the bank or adding a tangle of wall-warts.

First Impressions

Out of the box the PowerPlant ISO-2 Pro feels light but solid - it’s noticeably smaller than many multi-output supplies and easily fit under my compact pedalboard. The LEDs for each output and the supplied assortment of coaxial patch cables made setup quick, and the switchable outputs for higher voltages gave me immediate flexibility for pedals that need 12 V or 18 V. I expected a cost-focused product to cut corners, but the initial build and included cables left me pleasantly surprised.

Design & Features

Physically the unit is tiny - the low-profile aluminium chassis slips under most pedalboards with ease and the status LEDs for each output are bright and unambiguous, which I appreciated on a dim rehearsal stage. Functionally the layout is straightforward: two switchable outputs that can run 9/12/18 V DC at up to 500 mA each, and six dedicated 9 V DC outputs rated to 300 mA each - all reported as isolated, filtered and short-circuit protected. The unit is powered by a single external adapter (12 V/2 A on this model) and Harley Benton warns the total combined load must not exceed the specified wattage, which is important to respect when mixing high-draw digital pedals with smaller analog stompboxes.

Setup & Usability

Setting the ISO-2 Pro up was quick - I used the two 500 mA outputs for a multi-function multi-FX and my tuner, and put the rest of my 9 V stomps on the 300 mA outputs. The included 60 cm coaxial leads were long enough to route cleanly on my board, and the single Y-cable (voltage doubler) was handy for a couple of older pedals that needed a second supply rail. I did pay attention to the total wattage and per-output limits - pairing a 500 mA output with a hungry digital reverb plus a wireless unit would be pushing the limits if the total draw climbed too high, so I mixed high-drain pedals across the two switchable outputs during rehearsal.

Real-World Experience

In rehearsal the biggest win was the significant reduction of hiss and ground-loop related hum I previously had with daisy-chained supplies - the isolation is audible in a good way. Over several sessions the LEDs reliably indicated each output’s status and I experienced stable operation for the most part, but I did notice one quirk: on a couple of occasions the unit behaved as if it was starved for power when used on marginal wall outlets, causing the LEDs to blink or drop out until I swapped mains sockets. I also learned to keep an eye on connector compatibility with older pedals - many modern supplies use 5.5 x 2.1 mm plugs while some vintage stompboxes expect 5.5 x 2.5 mm, so adapters may be required for certain legacy units.

The Trade-Offs

The compromises here are mostly about capacity and connector standards - it’s not designed to replace a large-format 12-output pro distro if you run a lot of modern multi-FX or amp-modelers without separate adapters. Because the total output budget is limited, you’ll need to plan which pedals go on the higher-current switchable outputs and which can survive on the 300 mA lines. Also, while the chassis is solid for its size, the lightweight nature means it doesn’t add much protection against rough handling - I’d mount it under the board rather than leave it exposed on top during transit.

Final Verdict

Overall I found the Harley Benton PowerPlant ISO-2 Pro to be an excellent budget-isolated power supply for small to medium pedalboards - it gives you real isolated outputs, flexible voltage options, and a compact form factor that makes tidy routing a breeze. It’s not without quirks - watch the total wattage, verify plug sizes for older pedals, and be mindful of marginal mains outlets - but for players who want credible noise rejection and per-pedal isolation without spending double or triple the money, it’s an easy recommendation. If you gig with a modest pedal count or want to eliminate noise from a compact board, this unit delivers an outstanding price-to-performance ratio.