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4001CS bridge pickup signal - too much?

Posted: Tue Mar 23, 2010 9:17 pm
by miguelbass
Dear friends,

It always looked as the signal from my 4001CS bridge pickup is very hot. In fact I wonder if it's really too loud - some symptoms:

1-When I plug the bass directly to the sound card I notice a big difference of volume between bridge and neck pickup toggle switch positions.
2-When I plug the bass through the sansamp bass DI, even with the box turned off, the positions bridge and bridge + neck start distorting. To have the same effect on, for example my p-bass, I would have to turn the DI on and pump up the drive knob.

This last item can be related to the fact that the sansamp doesn't have an input level control, but it still means and sounds like the signal from the bridge pickup on my 4001CS is really too high. It's hotter than my active warwick! Do you have any suggestions on how can I verify what's happening? Maybe checking pickup height or how to check impedances?

Thanks for your help

Miguel

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Mar 23, 2010 9:43 pm
by johnallg
Miguel, the RIHS is wound to around 13-14k ohms and is really hot, where the neck toaster is probably a 7.4k winding. There will be an imbalance. Height adjustment and volume controls are the only way to balance them more. But your CS always sounds great in your videos.

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Mar 23, 2010 9:54 pm
by miguelbass
Hi John! OK, I'll measure impedances tomorrow to begin with. About pickup distance - I shall try control it with those big screws on the HS? I notice that the center cylinders (A and D string) are higher than the other ones. I suppose it's just like that. Thanks, John.

Miguel

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Mar 23, 2010 10:09 pm
by johnallg
miguelbass wrote:Hi John! OK, I'll measure impedances tomorrow to begin with. About pickup distance - I shall try control it with those big screws on the HS? I notice that the center cylinders (A and D string) are higher than the other ones. I suppose it's just like that. Thanks, John.

Miguel
Yes, the bridge pup height is controlled by the screws. The A and D pole magnets are actually longer and should stand up about 1.5mm higher than the E and G poles. The varying heights mimic the curve of the neck/strings.

Be aware lowering the RIHS will change it's tone also. :?

Re: 4001CS bridge pickup signal - too much?

Posted: Wed Mar 24, 2010 12:28 am
by mattj1stc
johnallg wrote:Miguel, the RIHS is wound to around 13-14k ohms and is really hot, where the neck toaster is probably a 7.4k winding. There will be an imbalance. Height adjustment and volume controls are the only way to balance them more. But your CS always sounds great in your videos.
I agree. When I first got my C64S, I didn't realize that there was such a difference in pickup output. Compounding this was the fact that you can adjust the horseshoe to be a lot closer to the strings than you can with the toaster. Not knowning either of these things, I put both pickups up as close to the strings as they could go without interfering, and the horseshoe in the bridge was at least twice as loud as the toaster in the neck. Eventually, I lowered the horseshoe down to where the volumes are more or less equal.

Re: 4001CS bridge pickup signal - too much?

Posted: Wed Mar 24, 2010 12:35 am
by johnallg
johnallg wrote:Miguel, the RIHS is wound to around 13-14k ohms and is really hot, where the neck toaster is probably a 7.4k winding. There will be an imbalance. Height adjustment and volume controls are the only way to balance them more. But your CS always sounds great in your videos.
For those not familiar with Miguel, this is his YouTube channel:

http://www.youtube.com/watch?v=cYQLy7Uc ... re=channel

Re: 4001CS bridge pickup signal - too much?

Posted: Wed Mar 24, 2010 12:51 am
by jps
That little old yellow .0047µf cap can help, too. :wink:

Re: 4001CS bridge pickup signal - too much?

Posted: Sat Mar 27, 2010 9:29 am
by Droog61
My 4001 v63 has a very hot bridge pick up... it starts to balance at around 6-7 on the volume.

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Apr 20, 2010 5:30 pm
by miguelbass
Hello again everyone. I checked the values not directly on the pickups but on a regular jack connected to the output. I have 12K for the neck , 9K for the bridge and 5.4K for both (middle position) which is almost what it would be calculated for parallel. I'm not sure what these mean but I think it's a normal set of values... oh yes - all knobs full open.

Thanks everyone!

Miguel

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Apr 20, 2010 7:21 pm
by johnallg
miguelbass wrote:Hello again everyone. I checked the values not directly on the pickups but on a regular jack connected to the output. I have 12K for the neck , 9K for the bridge and 5.4K for both (middle position) which is almost what it would be calculated for parallel. I'm not sure what these mean but I think it's a normal set of values... oh yes - all knobs full open.

Thanks everyone!

Miguel
Is your CS an early one - early 91-94? The toasters were 12k back then, and bridge pickups were not yet the 11k-14k they became later.

Re: 4001CS bridge pickup signal - too much?

Posted: Tue Apr 20, 2010 7:36 pm
by miguelbass
johnallg wrote:
miguelbass wrote:Hello again everyone. I checked the values not directly on the pickups but on a regular jack connected to the output. I have 12K for the neck , 9K for the bridge and 5.4K for both (middle position) which is almost what it would be calculated for parallel. I'm not sure what these mean but I think it's a normal set of values... oh yes - all knobs full open.

Thanks everyone!

Miguel
Is your CS an early one - early 91-94? The toasters were 12k back then, and bridge pickups were not yet the 11k-14k they became later.
Hi John. Mine was made January 30th 1996, #605.

Miguel