stevem Messages: 4733 Registered: June 2004 Location: NY
Senior Member
I play Bass also besides guitar and have both active and passive Basses.
I find that my Carvin Bass with a 18 volt active system drives these preamps very easily and I must keep the Baaees volume down a good amount.
My other Active Bass with EMG pickups and only a 9 volt system I only need to keep turned down a tad.
The other reason I ask is that in these K150 and K250 heads the factory made a change and added more gain to the 5066 preamp to better please guitar player by changing some resistors.
The change came about in Nov 1971 during the first production run and became permanent there after.
I have several of these amps and I find that my two early amps are better for my active Basses since I jump my amps two channels with a short cable.
This info might interest you?!
And no, these metal face amps are not as easy to blow the first gain stage out due to big signal levels as are the a plexiglass face amps.
On those a input signal of over 1 volt can pop them!