The Suhr Iso Boost is a boost pedal and line driver from Suhr that combines two things in one box: the clean boost circuit from the popular Suhr Koko Boost, and a transformer-isolated buffer designed to cleanly drive long effects chains. Suhr describes the result as a "beautifully transparent buffered signal along with the clean boost found on our popular Koko Boost"1.
"beautifully transparent buffered signal along with the clean boost found on our popular Koko Boost"
What it does and how it works
The Iso Boost is a clean, transparent boost with a transformer-isolated buffered signal. The buffer's job is to drive long effects chains cleanly, keeping signal strength intact across a big pedalboard, while the boost side pushes a tube amplifier harder. As a clean boost, its gain varies from unity, where it acts purely as a buffer, up to +20dB of gain1.
Because the boost is clean rather than an overdrive, it raises volume and hit into the amp without adding clipping of its own, letting the amp's own tubes do the work. In practice that gives the pedal two jobs:
- Boost: up to +20dB of clean gain into your amplifier1
- Line driver: at unity gain, the transformer-isolated buffer carries your signal through long effects chains1
- Remote control: on/off switching from a Suhr FxLink remote switching system1
For more on this category, see boost pedals; if you want the pedal to add its own breakup, look instead at overdrive or distortion pedals.
Bypass and buffering
The Iso Boost is true bypass when off, so it leaves your signal alone when you are not using it. A battery monitor watches the internal battery, and when the battery is too low the pedal automatically switches to true bypass, so a dying battery cannot leave you with a degraded buffered tone1.
The battery monitor means a low battery drops the pedal to true bypass rather than passing a weak buffered signal. If the pedal suddenly stops boosting, the internal battery is the first thing to check.
Left on at unity gain, the pedal works as a buffer, and the transformer isolation is the feature that sets it apart from a plain clean boost: it is built to drive long effects chains cleanly1.
Remote switching with FxLink
Like all Suhr pedals, the Iso Boost supports remote on/off via FxLink, Suhr's remote switching system. This lets you control the pedal from a switching setup rather than tapping its footswitch, useful on larger boards1.
How it relates to other Suhr boosts
The Iso Boost takes its clean boost from the Koko Boost and adds the isolated buffer. Suhr's boost line also includes the Dual Boost, a two-level boost announced in 2016, and the Mini Brighton Treble Booster, a treble booster rather than a full-range clean boost.
| Suhr pedal | Type | What sets it apart |
|---|---|---|
| Iso Boost | Clean boost and line driver | Transformer-isolated buffer for long effects chains, up to +20dB1 |
| Koko Boost | Clean boost | The boost circuit the Iso Boost borrows, without the isolated buffer1 |
| Dual Boost | Two-level boost | Two boost levels in one pedal |
| Mini Brighton Treble Booster | Treble booster | Boosts treble rather than the full range |
Videos
N Stuff Music
N Stuff Music
Vertex Effects
Questions
What is the difference between the Suhr Iso Boost and the Koko Boost?
The Iso Boost uses the same clean boost circuit found on the Suhr Koko Boost, but adds a transformer-isolated buffered signal. That buffer is designed to cleanly drive long effects chains, which the Koko Boost on its own does not address.
Does the Suhr Iso Boost work with Suhr FxLink?
Yes. The Iso Boost supports remote on/off switching via FxLink, the remote switching connection offered on all Suhr pedals. This lets you switch the pedal from a remote switching system rather than pressing its footswitch.
Is the Suhr Iso Boost true bypass?
Yes. The Iso Boost is true bypass, and it stays that way even when the internal battery runs low: a battery monitor automatically switches the pedal to true bypass so a dying battery does not degrade your signal.
Can the Suhr Iso Boost be left on as a buffer?
Yes. Set to unity gain, the Iso Boost works as a buffered line driver, with its transformer-isolated buffer passing your signal cleanly through long effects chains. It can also add up to +20dB of clean gain.
Sources (1)
- ISO Boost, Phantom48 (phantom48.com)
