We don’t just tickle output valves with a few polite volts and hope for the best. No, we run them at the sort of voltages you’ll actually find inside a real amp – the levels where the magic (and sometimes the smoke) happens.
Every set comes with its own test certificate, spelling out exactly what conditions the valves endured. Think of it as their gig contract – proof they’ve already played the loud bit before they arrive at your amp.
And here’s the kicker: we test them in a proper output stage, with a real output transformer. No cushy lab environment. These valves are thrown straight into the mosh pit they’ll actually be living in.
Take the 6V6, for example – the workhorse in many a Fender. They usually run around 410–430 volts. At a measly 300 volts, a quartet might look perfectly matched, like a well-rehearsed barbershop group. But crank them up to 430 volts and suddenly they’re more like a pub karaoke night – way off.
With higher power valves like the EL34, things get even spicier. AVO testers top out at 400 volts, which is sweet enough if your amp is polite. But at least one Marshall happily hurls them along at 550 volts. So unless they’ve been tested at proper head-banging levels, how can you be sure they’ll stay in time and not hiss and squeal when the amp is cooking?
For day-to-day testing of EL34s, we’ve chosen 470 volts – a sensible sweet spot that covers most of the market. But if you’d like the reassurance of testing at full “stadium rock” levels, just say the word. We’ll crank the dial, test them, and hand you a certificate proving they survived the ordeal.
And because we’re not into smoke and mirrors (except the ones on stage), our blog shows you the actual test gear we use. No mystery boxes, no fairy dust – just serious kit making sure your valves are ready to go all the way up to eleven.