Hum and noise

[Mlazarus]

Mica told me 2 years ago the new pickups cost about $9000.00. So, pickups are definitely out of the question. It will(hopefully) only be the electronics. I don't want to pay more than $2000.

[hammer]

I agree with Stephen’s suggestion. Call Mica. When mine went in, she indicated it could be anywhere between $900 to $1,800 (my bass also needed a new hum canceler). The cost didn’t hit $2,000 but it was definitely on the high side of the estimate for the bass. Factor in shipping with insurance (that costs more than the shipping) and with a two way trip add about $600 to the costs.


 When I got my bass back Mica was somewhat apologetic that while Ron quieted it down a lot, it wasn’t completely silent. Well Ron must have a lot better ears that I do because I can’t hear any hum at all and it’s now been played in a number of different venues with no problems (and no need to restrict where I’m standing). So, it was definitely worth the wait. While there are some repairs on Alembics any competent luthier can do,nthis type of work is not that kind of animal.  One needs to go to the source and that is Alembic and Ron. As Stephan indicated, ask about what the wait is going to be a see if you can reserve a place and send it in close to when they figure they will have time for it.

[Mlazarus]

I'll call very soon. This will complete the process of an upgraded series 1.

[lbpesq]

Brother Brian is absolutely correct about the upgrade being a job for the Mothership.  Ron, in best mad scientist mode,  invented a rig that creates super RF interference that he uses to calibrate Series instruments.   If it’s adjusted to be quiet in Ron’s electronic torture device, it will be quiet just about anywhere you might be playing.  Not the kind of job you can trust to your local luthier.

Bill, tgo

[Mlazarus]

I need to call Ron on this.

[Mlazarus]

How effective are the noise suppressors like: Lehle DC filter or i believe a ground on/off switch on a direct box, such as the Tech 21 Sans Amp.

[JimmyJ]

The ground lift switch on a DI would only help if you have hum when the bass is on standby. That relates to a voltage potential or "ground loop" caused by your power supply, your amp, and the mixing board on the other end of the mic cable being connected to different power sources.  Sometimes that will make your amp hum, or make the input to the mixing console hum - and lifting the DI ground can sometimes resolve it. 

What I believe we're talking about here is also not an issue that involves DC leakage onto the audio line.  (DC by nature is not hum but causes other odd issues). 

If your bass is dead quiet in standby but hums when you turn on the pickups, and varies as you move left and right, then it is simply your large single coil pickups "hearing" and amplifying ElectroMagnetic Interference which is generated by poorly shielded electronics or AC sources.

Get your output levels set to an agreeable volume, go through the hum balance procedure, find the quietest direction to point the headstock, and THEN decide if your noise floor issue needs further attention or if it's something you can live with.

We all hope you will spend as much time as possible playing and enjoying that bass.  Try not to get caught up obsessing about details.  Make music!!

Jimmy J

[Mlazarus]

Oh, i intend to play. I just have the excitement of finally getting my favorite bass. Took a loooong time. I'm also learning FAST from all of you, but i need to understand the "character" and behaviors of this monster. to play without worry, etc....

Mica told me that if there is hum and noise at a gig, it won't be heard during playing. That is definitely true! I own a 67' flip top Ampeg tube amp. Very noisy. I never worried because that's it's nature, but when it's time to play, you can't hear the noise. I still may do the upgrade though.

[mica]

Let me clarify - I said that some low levels of high frequency noise won't be an issue once you start playing, if you were considering NOT getting the RF upgrade.

For low-frequency hum, it can all be eliminated from the bass with the existing hum-balance controls. You may have other sources of hum in your signal path, but the bass you have the way it is now will be able to eliminate everything 60Hz.

[Mlazarus]

Thanks Mica. Also, i may do the upgrade etc...when you all give me the green light which i know will be several months from now. I'm looking forward to the total estimate.

[jazzyvee]

Hi Mica, you mention 60Hz specifically, so does that mean that those of us in countries with 50Hz ac power will not get as much LF hum elimination as those in the USA?
My basses seem to be fine, but just a thought.

[JimmyJ]

Ha!  Jazzyvee, I'm sure Mica meant no disrespect for our 50hz friends.  But I believe the idea is that low frequency EMI is easier to cancel with the Alembic system because the waveforms are literally slow enough, or large enough to be "heard" at the same time by the pickups and the hum cancelling coil.  The problem comes when you have higher frequency interference because as the waveform gets shorter the pickups and hum cancelling coil start to "hear" it at different times, or in different phases, and that makes it less likely to be cancelled. 

I'm self-taught in this area so excuse me if I'm not accurately representing the science.   

Jimmy J

[jazzyvee]

You are now teaching me Jimmy J. 👍🏾

[mica]

Jimmy is of course correct. I sometimes fall into the typical American-centric speak. 50Hz cancels just as fine as 60Hz, Vince.

[Mlazarus]

Correct. I communicated earier. Mica told me exactly what you said. It's just a time thing now. I know we have to be patent. Thank you.