Valve Bias Play Time
Hi All
Have been playing with the bias adjustment on my amp this evening. An Almarro 50125A with 6550 valves by Tung-Sol.
Originally I had the bias set at 150mV. This is the only valve amp I have owned that requires manual bias adjustment. Considering how many valve amps I've owned over the years it's a first.
While checking the bias value (which had not changed from the last check) I decided to raise the bias to the max value noted in the manual which is 160mV.
Back on went the music and immediately found the bass quite noticably firmer and punchy and the mids and highs a touch more open or clear may be a better description. The changes are evident on both CD and vinyl.
I hadn't reallised what a change in sound I was going to get with such a small change in bias. I must admit I do like the change in character and presentation of the amp, bass definition and drive from the bass of Marcus Miller and Metallica much improved.
Has anyones else found this of have you adjusted your bias to greater or lesser values than recommended my the manufacturer
Having some thoughts now on looking at the valve compliment in rest of my gear, Pre, Phono, DAC and dirvers for the power amp and wondering if some changes there could have some useful results.
Andy - SDDW
Perceived changes to sounds ect were in no way influenced by the bottle or so of Red Wine I've just consumed.
HV Electrical Engineer - SAF (Sustainable Aviation Fuel) Plant