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Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 12:49 am
by cassius987
Has anyone done a test to, to put it one way, see if a 4000 sounds different from a 4001 or 4003 plugged into the ROS jack? In other words, remove the pickup from a 4001 or 4003 and compare the output from the ROS jack (bridge pickup isolated) to when the pickup was installed?

If not I would probably be willing to do a test later this week for my own benefit. Feel free to suggest riffs you may want to hear...

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 1:07 am
by antipodean
My '00 V63 (fitted with a Lollar HS) sounds very much like my '74 4000 when I solo the bridge pickup (both have medium gauge nickel round-wounds). I have the toaster set rather low on the V63 to balance pickup outputs.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 7:23 am
by Colonel Sanders
The bridge pickup on my 77 4001 taken from the ROS sounds quite a bit like my 72 4000. To the extend that it is a different pickup... but to give you an idea, it is "snappier" or q"uicker" than from the normal output. I get the same quicker feel from my 4000.

I just adore this one...

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 10:45 am
by woodyng
Just remember to turn the cap off,if possible. I think the 4000's lack of one is probably the main difference in how it would sound compared to the solo'd bridge pickup of a 4001. And the pickups in a 4003 are going to be so much hotter,they probably won't sound as crisp and distinct as the 4000's lower output pickup. I've met a guy here that has a 4001,but i haven't had a chance to see it yet. (I think its a mid70's MG from his description) maybe we can do a comparo....

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 10:56 am
by cjj
I think the question here is whether or not having the magnets of the second pickup present, even if not using that pickup, will affect the tone...

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 11:19 am
by cassius987
cjj wrote:I think the question here is whether or not having the magnets of the second pickup present, even if not using that pickup, will affect the tone...
Exactly. Has anyone tried this? If there's an effect it should be observable if the other conditions are held constant (pickup type, wiring, plugging into the ROS jack both ways).

Also... "effect" not "affect". Ugh. Stupid Good ol' Jack Daniels.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 12:20 pm
by woodyng
Sigh,ok,i should know better than to try to get involved with this techie stuff.... 8) :lol:
Good luck on your journey..... :wink:

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 3:12 pm
by jdogric12
Of greater import is the extra wood in a crucial spot that enhances sustain in a 4000.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 3:26 pm
by woodyng
Of no real importance to this thread, but fyi,my 4000's younger twin is fer sale on the 'bay....a white '76 in really clean condition.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 5:43 pm
by cassius987
jdogric12 wrote:Of greater import is the extra wood in a crucial spot that enhances sustain in a 4000.
See, that's the thing, a claim needs to be testable to really be proven. Unfortunately that claim is a lot harder to test than what I'm asking, or else it's another great question to ask (i.e., does that extra wood change the resulting sound). You can compare a 4000 and a 4001S with 4000 circuitry and pickup, but the internal variance (between basses) in the construction or even quality of the wood used for the neck or rest of the body may be so great that you haven't isolated the variable here (that extra mass); besides, several 4000s were routed so you'd have to check first. And many are set neck which is its own (massive) variable.

The hypothesis I'm going after is that the magnetic pull on the strings, which definitely can change how strings vibrate in several cases (especially the bigger the gauge and the stronger the magnet), is having an effect on the sound. I'm not sure if it is or isn't. But I've seen alnico pickups, for example, change the character of E and B strings before when they are in the neck position (where the string is looser so that magnet can more easily affect the behavior).

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 5:59 pm
by Colonel Sanders
cjj wrote:I think the question here is whether or not having the magnets of the second pickup present, even if not using that pickup, will affect the tone...
Ooops... Shoulda read the question in the header...

Probably not an easy thing to investigate considering all the other variables that you cannot isolate.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 6:02 pm
by cassius987
Colonel Sanders wrote:Probably not an easy thing to investigate considering all the other variables that you cannot isolate.
Really? Just remove the neck pickup, continue to use the ROS jack. The bass is the same; the strings are the same; the wiring's the same. The only thing that has changed, because you are using the ROS jack and not the mono, is that one of the magnets is gone.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 6:07 pm
by cjj
cassius987 wrote:
Colonel Sanders wrote:Probably not an easy thing to investigate considering all the other variables that you cannot isolate.
Really? Just remove the neck pickup, continue to use the ROS jack. The bass is the same; the strings are the same; the wiring's the same. The only thing that has changed, because you are using the ROS jack and not the mono, is that one of the magnets is gone.
Yep, should be pretty easy. The magnets will definitely affect the string vibration, though without the pickup coils connected, you won't be extracting nearly as much energy. My gut feeling is that you won't hear much of a change, but actually figuring it out would take more info on the magnets, strings, etc. and WAY more math than I've done in years. Much easier to go the experimental route...

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 6:36 pm
by cassius987
cjj wrote:Yep, should be pretty easy. The magnets will definitely affect the string vibration, though without the pickup coils connected, you won't be extracting nearly as much energy. My gut feeling is that you won't hear much of a change, but actually figuring it out would take more info on the magnets, strings, etc. and WAY more math than I've done in years. Much easier to go the experimental route...
My guess is it depends on the pickups, but by and large I suspect there will be little difference. I probably need to do some long notes to measure sustain as well. I think Toasters might have the most pull so they would probably be the most ideal to test... however the bass I have wired to do this properly right now has HB-1s. So it may not be worth the hassle. Still, I would really like to know what might change, as by and large with that bass I have just been using the bridge pickup lately. On other basses I have found the neck pickup completely essential so removing them would be out of the question.

Re: Affect of neck pickup magnet on bridge pickup tone

Posted: Mon May 13, 2013 6:47 pm
by antipodean
A minimalist test would be to see if there is any appreciable difference in tone on a 4001/3 with the bridge pickup soloed where the neck pickup is set to different extremes of adjustment. Given there is an inverse square relationship between distance and magnetic attraction, there should be an appreciable difference in the impact of the magnetic field on string vibration as pickup height is varied.