Series bass Hum cancelling.

[jazzyvee]

I'm hoping to use my series basses live more often this year. I've read on the forum a few times that some members, I think JJ, has to occasionally adjust the hum cancelling trim pots depending on the venue to keep things quiet.
I've not experienced the same kind of level of noise you get from single coil guitars live from my bass yet, although my shorty is less quiet than the others which are silent. However, I wonder if I was at a venue that was "noisy" and my series bass was picking up noise, that could not be completely cancelled out, is it likely to be louder in my signal chain than it is for a non alembic guitar/bass because the hum cancelling pickup is there to deliberately pick up noise?

[grateful]

I don't remember that Jazzy;  I remember Jimmy saying he had to orient his bass to ensure the source of noise is equidistant from the pickups and the hum canceller

[JimmyJ]

Hey cats,


You may be remembering my story about the noisiest studio I'd ever come across.  I've only worked there once since having Ron's magic "even quieter" upgrade and the room still has issues.  But I'm not alone in that place, they're used to the problem and have it with various pieces of their gear.


Jazzy, when Ron upgrades an instrument he literally dials in the most effective settings on the trimpots and I've had no reason to touch them since.  I think he might even seal them with a sticker once he's found the optimal settings. 


Ron's rig includes noise generating coils which he puts the instrument in as he tunes the electronics.  Despite the fact that a change of orientation to the noise source may produce some artifacts, there is an optimal setting for the hum cancelling trimpots and once you've found it there should be no reason to change them.


I think that applies to instruments without the upgrade too.  Before the upgrade I rarely attempted to adjust the hum balance once I had it set.  Instead, I was resigned to finding the quietest direction to point the neck and standing in that position during the quieter musical passages.


Don't be misled by the idea that the hum coil is hearing and amplifying noise.  The fact that it's out of phase to the pickups will still make it much quieter than any other single-coil setup.


Jimmy J

[jazzyvee]

Thanks for the correction Grateful and JJ, you have reassured me.

[s_wood]

Jazzy, I routinely gig with my Series basses in rathole bars with crummy electrical systems and neon beer lights all over the place, and my basses are almost always dead quiet. On the view occasions where noise was a problem I've found it to be quite directional in nature, and so simply turning my body one way or the other has been quite effective in significantly reducing the noise.  In short, I wouldn't worry about it - Alembics are made to be played!