What Do You Hear When Your Amp Needs Biasing?


Hi, Everybody,

I was listening to my rig the other day and noticed that some (but not all) closely miked recordings of female singers (Diana Krall on some of the cuts on "When I Look in Your Eyes" comes to mind) sounded a bit edgy or harsh. I checked the bias on my Manley Mahi amplifiers and found that some of the values on the multimeter, which should have been at 250, were as low as 240. I made the bias adjustments and, lo and behold, the vocal tracks sounded better. So I'm wondering what, in general, is a tipoff that a to be of a fire needs to be biased?

Thanks!
rebbi

Showing 1 response by robsker

On my Ayon Spirit II I audibly hear certain piano transients as having a ringing to them. Also, harshness in clarinet, some vibes transients, and some sibilance in female voices. What rectifies this situation is biasing to ensure that all 4 tubes are at the ideal setting, and moreover, that they are set identical to one another. When the adjustment is done, these distortions/harshness issues go (almost completely) away --- being reduced drastically.