Peavey T-40 help

[seany_ryan]

Hey I have had many wonderful basses and used to own a T-40. As life goes I had to make ends meet and sold it off 7 years ago. Now I have an beautiful 78' model BUT.....it has a bad hum/buzz when you turn the treble up. I use overdrive pedals and that just intensifies it more.

Is there a way to fix this on my own? Add more grounding to the input jack? Any ideas?

 

[Josh Emmons]

im not a sound guy, nor an electronic guy, but possible if you took the entire basses EQ down, then you might get less hiss, and have a still similar ballanced sound, (just turn up the volume up on the bass, rather than the amp. (sorry if this doesn't help... also, if possible if it possible to do the same to some of the pedals?)

 

[seany_ryan]

I tried that and it is the bass. Not one of my other basses does this. I feel the T-40 has some kind of wiring issue but I am just not sure. Thank you though that was my first idea.

 

[zachoff]

I'd take it to a tech. The wiring on those things is nuts. You might get charged an hour's worth of work but you'll be back to good.

 

[kjpollo]

I'd take it to a tech. The wiring on those things is nuts. You might get charged an hour's worth of work but you'll be back to good.

Sad to say but I think this is your best bet. One thing- is the buzz still as bad if you lower the treble below 7? When you have the treble at 7 or higher, the pickup goes into single coil mode which can definitely produce more hum/buzz.

I wonder if a previous owner had some wiring work done and something went awry. Mine is a 78 or 79 and I dont have any issues like that.

 

[MNAirHead]

Sounds like someone has dorked it or lost the grounding.

The wiring is the same as a T60 (easier to find diagragms)

 

[dangnewt]

............... One thing- is the buzz still as bad if you lower the treble below 7? When you have the treble at 7 or higher, the pickup goes into single coil mode which can definitely produce more hum/buzz............

This was my first thought. Is the buzz loud when you have both Pups on and both tone knobs above 7 but the volumn knobs the same? Is the hum bad in every room that you play?

I hope, for your sake, the hum is single-coil and a function of the electric system and lighting where you play. If not, a good tech is the way to go.

 

[laklandplayer]

When you turn the tone all the way up on a T40 the pickups become single coil. You have to back it down to 7 or so for the humbucking to happen and then its treble roll off after that. You are probably hearing 60Hz single coil hum.

 

[Staccato]

PM sent to Seany Ryan. If anyone wants the wiring diagram, PM your email address and I'll attach the pdf to email, and sent it to you.
It's too large to attach to a TB post.

-John

 

[seany_ryan]

Yes the humming/buzz is bad after 7 on the treble. I like all the way up because I pick, pop/slap and finger on a lot of songs. I move between those a lot while playing the Sam song for many songs.