The Trumpet needs 15-16Vdc on the power input with the correct plug configuration. I believe the polarity is indicated on the receptacle. Whether that is from a switching or linear power supply is of no real consequence other than how each sounds.
Speedboost or other lps for Hagerman Trumpet MC
I have been really enjoying this unit so far and now have Tele ac7 smooth plates (curve trace matched low noise and non-microphonic, thanks Brent Jessee) and a fantastic pair of Valvo e82cc triple mica in the au7 sockets. I think I have the tune combo I want.
I have read about folks using lps for this phono stage and I am a little confused as to how it could make sense since the power supply in the Trumpet MC is a switching one. Can anyone explain how lps would affect the onboard power supply or would one need to somehow bypass it, and if so how would you do that without rebuilding the unit?
lastly I saw @lewm recommend 12fq7 as a substitute for 12au7. Looking at the data sheets, they are similar with identical on out, but not identical. Has anyone tried this and if so what was the result? Sheesh, guess I am not done tube rolling after all.
thanks