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Bass amp question

PostPosted: Mon Jul 17, 2006 11:50 pm
by bigdaddy
I bought a Fender Bassman 150 on Saturday and used it at an outdoor show Saturday night. The amp sounds wonderful but what is the ground lift switch for. Why and when would I consider using it? I can't find any info on the device at so I'm hoping one of you know how it works. Thanks, Big Daddy.

PostPosted: Tue Jul 18, 2006 12:27 am
by ricochet
This is an old amp with a two prong cord, right?

They provided a "Ground" switch with those. One end of the switch is connected to a capacitor that's connected to the chassis. The other side of the switch connects to either wire of the cord, or to nothing in the center position. It grounds AC signals from the chassis to the neutral side of the cord. If the switch is connected to the "hot" side of the cord, there's more hum and you will get a tingly shock if you touch your guitar strings while touching anything grounded (and this will really get your attention if you touch a grounded mic with your moist lips.) If the cap shorts out, you can be directly connected to the power line, thus the cap's popular name, "The Death Cap." All older amps with this arrangement should be converted to a three-conductor cable with the third ground wire directly connected to the amp chassis, and the switch removed or disconnected.

PostPosted: Tue Jul 18, 2006 6:18 pm
by bigdaddy
This is a brand new amp. Three prong cord. It has a "ground lift switch for recording or live sound" is what the adverstisement says. These amps are pretty new in the Fender line up. It's a Bassman 150, 150 watt 1 12 speaker combo amp. 39 bloody pounds is all it weighs. I can carry it with one arm. It also has a built in compressor/limiter which I am finding is great. The others in the band love it because my notes are all even in volume, more flowing. It came in last Saturday so I rush it home and then used at an outdoor gig Saturday night. It sounds really good. I'd better jump on the Fender sight and send an e-mail asking for more details on this feature. Thanks.

PostPosted: Tue Jul 18, 2006 10:29 pm
by bigdaddy
I found out. Down loaded the manual from Fender. It is for the line out. It lifts the groud, the third pin on the line out. It may reduce hum in certain situations. Saturday I used this line to the mixer and it worked just fine but I'm glad I know in the event hum starts up while plying live or recording. This amp really does sound sweet. I'm impressed. I'll use my heavy tank in my house from practice.

PostPosted: Wed Jul 19, 2006 2:40 am
by ricochet
OK. Thanks for the followup!

PostPosted: Fri Jul 28, 2006 6:31 pm
by bigdaddy
Learned some new stuff on this amp. Turned the contour all the way, the freak knob all the way down to 150 and then turned it's level knob all the way up and bam, the mids came to life. I did the same with that other freq knob, down to 800 and the level all the way but didn't get as big a bang. This little amp is so cool. I'm suppose to turn the compressor knob up until I feel I have control of the guitar. I gots to have that comp knob all the way. I have to cut the note off manually or else the bloody thing will ring on forever. Was weird at first but now I'm gettin' use to it. No more hard hits, everything is level and flowing. This amp was good buy for a simpleton like myself. I got a good tone from it them marked all the levels so I don't have to guess.

PostPosted: Fri Jul 28, 2006 6:49 pm
by ricochet
I know fishermen who'd pay a pretty penny for a real bass amplifier. Usually they just have to hold their hands wider and wider apart and talk about the bass.

PostPosted: Thu Sep 14, 2006 11:36 pm
by bigdaddy
Went back to miking this Bassman 150. The line out had a volume but it had to be pre-eq or else the signal was to hot. With the mic I get the warm raunch comin' off that 12 inch speaker out to the ears of the audience. Them line outs must just be for recordin', I don't know. Having the lower volume on stage is nice. This amp can easily out volume everything else. On stage I have the pre set at about 3 and the post sittin about 4 and it's loud. 39 pounds is also sweet.

PostPosted: Fri Sep 15, 2006 12:45 am
by ricochet
Yeah, that's pretty handy!