One of the questions we’ve been asked the most since the reveal of the ReVolt series goes a little something like this…
…fuelled by 200v and genuine tube power” but runs on 12vDC?…
Excellent question! We’ll give the floor to Téo, one of the main Electronic Engineers here at Two notes Audio Engineering…
The voltage is stepped up internally using a boost converter, also known as “step-up converter”. The result? The 12AX7 tube operates exactly where it is intended to, providing you with the best sound possible! That’s also why disconnecting the power supply when changing the tube is essential!
Back in the day, elevating the voltage from the mains supply to the levels required to power amplifiers was actioned via transformers, but those are only suited to convert AC voltage. Stepping up a DC voltage requires a DC/DC converter, an architecture that’s extremely common in the world of electronics as we know it.
In a little more depth, a boost converter is one of the simplest types of switch mode converter; the very same you see in electric cars where 300V to 400V are commonplace – the battery that needs to supply 500V – you guessed it – has a boost converter! Boost converters were originally designed in the ’60s to power the electronic systems in Aircraft; as such, they were designed to be incredibly small and as efficient as possible (up to 99% efficient to be precise).
We won’t go into a major technical breakdown here, but there are many excellent resources online that explain how they work.
In a nutshell, they’re very small, super efficient and massively integral to the ReVolt series, providing the optimum baseline power requirement for the tube in the pedals.
Fun fact – The Revolt’s signal path is hybrid Tube & semiconductor, but the entire signal path runs at 200V, semiconductors included. This allows us to have the headroom and dynamics required for the tube to deliver its true character and tonal response, making the ReVolt sound – and more importantly – feel like you are playing through your favorite tube amp, right at the sweet spot.
