leftside
Headphoneus Supremus
I'll have to do a little more digging on auto bias vs fixed bias with the Amplitrex. Have you also hooked it up to a laptop and plotted the curves? It's pretty cool.I am very fortunate to have a shop 5 minutes away from my house that lets me rent time with the Amplitrex.
It does come in extremely useful for my obsession with buying tubes from eBay. Many sellers list NOS, and sell tubes that are very low. Even if you run the Amplitrex in “Auto Bias”, well used tubes may auto bias to look much better than with the fixed bias setting.
Just today I tested some Tung Sol 6AS7G that were listed as “NOS”, fixed bias showed very low, but auto bias looks pretty good. I’ve never had a seller argue with me when I send the the test results.
I also scored 4 MELZ, a Mullard metal GZ34, and a pair of Tung Sol 6C8G that all tested new today. Low scores on pairs of Mullard 6080, and TS6AS7, but the 5998’s more than make up for it.
Nice haul you got there.