FourT6and2
Well-known member
Grabbed a Helios 50 local for a decent price. It sounded ok and I figured I could mod it to be better. A little ragged and cold and anemic. Original tubes so I figured I'd go over the amp and measure all the voltages and make sure it's healthy. It came biased from Bogner at 33% (17.5mA @ 470v). And it wasn't because the tubes had drifted. The bias pot was literally almost all way at zero. Adjusted bias to 60% and it sounds so much better. More pissed off. More authority. Less ragged/cardboard harshness.
The point here is I bet people try an amp and hate it because it was biased wrong and didn't know it. And I'm also willing to bet all the times people say they tried multiple amps of the same model and noticed one sounded better than the others... it's again—in part—due to improper bias. Biasing an amp so cold, will make it sound like garbage. BUT... the tubes will last longer and I'm 98% certain that's why many amp companies ship their amps biased cold (fewer warranty claims).
I bought a new Hiwatt Super-Hi 50 a few years ago. Straight from the factory to my doorstep. Custom ordered. Custom made just for me. No middle man. It arrived with one tube biased to 110% and the other biased to like 45%. Again, if you just plug in and play, it sounded like garbage. But after a bias adjustment...
So yeah, PSA: Bias your amps when you get them, even if they're brand new.
The point here is I bet people try an amp and hate it because it was biased wrong and didn't know it. And I'm also willing to bet all the times people say they tried multiple amps of the same model and noticed one sounded better than the others... it's again—in part—due to improper bias. Biasing an amp so cold, will make it sound like garbage. BUT... the tubes will last longer and I'm 98% certain that's why many amp companies ship their amps biased cold (fewer warranty claims).
I bought a new Hiwatt Super-Hi 50 a few years ago. Straight from the factory to my doorstep. Custom ordered. Custom made just for me. No middle man. It arrived with one tube biased to 110% and the other biased to like 45%. Again, if you just plug in and play, it sounded like garbage. But after a bias adjustment...
So yeah, PSA: Bias your amps when you get them, even if they're brand new.