EUB Project

[scojack]

Hello folks.
I have recently started a project to build an electric upright bass. The construction is near completion and i now have to turn to the electrics. There are no off the shelf products for this so its through necesity that i have to make a pickup. My expertise lies in wood-whittling and TBH this whole pickup winding thing is way out of my depth but i have no option but to continue, i need some help/advice from the experts hence my post.
I am planning a simple split-coil job, with 1 coil for A&E strings and one coil for D&G wired to hum cancel. Now, i have them ready for winding and have ordered some 42 AWG wire from Stewart Mac.The polarity of the magnets on each is reversed. (I've managed to work this out so far).
Can anybody suggest how many winds on each coil and what impedance should i be aiming for and should i wind each coil in different directions?
Any help with this would be greatly appreciated.
IanM

[David Schwab]

What kind of tone are you looking to get? Like an electric or an upright?

If you want to get a clear tone, keep the winds on the low end, maybe 5,000 per coil. You will have lower output than some passive pickups, but it will be very natural sounding. You can use a preamp to bring the level up.

If you want more of a P bass tone wind 10,000 turns per coil.

Did you manage to get the two coils to match the curve of the fingerboard?

You can wind both coils in the same direction, and then wire them start to start, or finish to finish. If you wind them opposite, wire them start to finish.

[scojack]

eub

Thanks David much appreciated.
I just plan to 'tilt' each coil slightly so that the distance to each string is roughly the same, unless there is another option that i havent thought about.
Would this cause any problems?
PS seen your basses & pickups on one of your links .... stunning!

What kind of tone are you looking to get? Like an electric or an upright?

If you want to get a clear tone, keep the winds on the low end, maybe 5,000 per coil. You will have lower output than some passive pickups, but it will be very natural sounding. You can use a preamp to bring the level up.

If you want more of a P bass tone wind 10,000 turns per coil.

Did you manage to get the two coils to match the curve of the fingerboard?

You can wind both coils in the same direction, and then wire them start to start, or finish to finish. If you wind them opposite, wire them start to finish.

[David Schwab]

Thanks David much appreciated.
I just plan to 'tilt' each coil slightly so that the distance to each string is roughly the same, unless there is another option that i havent thought about.
Would this cause any problems?

That should do it. The other option is one pickup per string like on the NS basses.

PS seen your basses & pickups on one of your links .... stunning!

Thanks!

[scojack]

eub

David,
Yes i saw that on the NS basses but thought i'd go for a slightly easier compromise . As for the tone, i would like it to be more natural so following your advice i'll go for ~5000 winds and see how it goes.
Thanks again.
IanM

[David King]

EMG sells those single pickups to builders. Bill Bartolini also makes a set that works pretty well. There's the Pierre "String Charger" and last but not least you can get custom alumitones for upright bass and cello from Don Lace that match the curve of your fingerboard.

Location of the pickup determines the sound as much as anything in my experience. If you mount it at the end of the fingerboard it will sound an awful lot like a P bass. I like them about halfway back to the bridge or better yet make it movable.

Keep in mind that a longer (read taller) magnet will throw the field further up towards the string than a short mag and coil can and since the excursion on an upright string is enormous, you want a tall field with plenty of room. 1/4" or 3/8 dia x 1" alnicos would be a reasonable starting point.

[scojack]

Thanks David,
I didnt realise EMG would maybe sell a one off set of those, i'll definately try that if i get another commission. I am planning the pickup midway between fboard and bridge. Very Interesting point about using 1" magnets as well, the ones i have arent quite as long as that. Jeez wish i'd sought advice earlier on this, im already over budget as it is.

[David King]

Send an email request to Marilyn at sensmag.com and she will airmail you some unmagnetized samples for free. Allmagnetics.com might also sell the 1/4" x 1" I think and they are only $.40 ea or something, not sure what the minimum would be.

[scojack]

eub

Cheers David, i'll look into it.
Heres a few photos for those interestd...

http://www.yaskawa.ac.psiweb.com/bass/bass1.htm

Send an email request to Marilyn at sensmag.com and she will airmail you some unmagnetized samples for free. Allmagnetics.com might also sell the 1/4" x 1" I think and they are only $.40 ea or something, not sure what the minimum would be.

[David Schwab]

Cheers David, i'll look into it.
Heres a few photos for those interestd...

http://www.yaskawa.ac.psiweb.com/bass/bass1.htm

Nice scroll! I'm so used to seeing EU basses looking very modern, such as NS basses.

That's going to be a looker!

[scojack]

Cheers David,
The 'classical guitar' type was just way tooo easy, im old school .
I picked up a figured Walnut board a while back and certainly found a good use for it, handsawing the bookmatch for the back is not something i would recommend though.

IanM

Nice scroll! I'm so used to seeing EU basses looking very modern, such as NS basses.

That's going to be a looker!

[David Schwab]

I've got an 85 year old King Mortone upright. It needs a little work, but it's in very nice shape.

I'm always looking at it thinking what beautiful curves.

[Bruce Johnson]

Ian;

Is this bass just something that you're building for yourself? Or are you developing it into an instrument to build and sell?

I may be able to help you with pickups, by selling you a modified set of the "M-pickup" group that I make for my own Scroll Basses. They're separate coils for each string, with three 1/4" Alnico5 magnets in each, arranged along the line of the string. They're powerful, and intended to give a thick rich tone with flatwound strings. I use them in a simple passive circuit. In this configuration, they're set up for a 4" radius fingerboard, which is what I use, but different bracketry could fit them to whatever radius you like.

You can reach me at brucejohnson100 at att dot net

[David Schwab]

Bruce, you make some cool and unusual things! I like them.

[Bruce Johnson]

Thanks, David! Those are the newest versions of my M-pickups. I've added the perforated brass shells for shielding, and they also add a classy look. The tops are 1/16" macassar ebony to match the fingerboards. The magnets are 1/4" dia x 3/4"; 3 per unit. I make my own bobbins by casting them out of polyurethane in silicone molds. The coils and shells are cast solid in black epoxy.

I'm not looking to get into large amounts of pickup building, but I've thought about offering kits of these particular pickups for EUB builders. I haven't worked out a price yet, but they wouldn't be too expensive. I'm already all tooled up to make them for my basses.

My P-pickup system, the elaborate mechanical percussive pickup under the bridge, isn't for sale.