Help with diagnosing very thin and tinny single coil pickup

Chuck Snider R.I.P. · From: West Virginia, USA - Morgantown, WV

I have an MSA Classic D10, that I was using as a practice guitar that unexpectedly started sounding extremely thin/shrill/tinny. I believe the single coil pickups are the originals, and nothing has been changed since I've had it (2 or 3 years?). I have played it occasionally before now and it sounded ok. I recently set it up at a bandmate's house for practice sessions. Because I didn't need unlimited volume, I played it through a Fender Vibro Champ. I know it isn't ideal, but it was adequate for the intended purpose. Sounded ok for a few practice sessions (between 2 and 6). I recently had to replace my gigging amp (G-K MB200) with a Quilter MicroPro Mach 2. The new amp sounded great plugged into my gigging guitar (GFI U12 Ultra). So, was looking forward to hearing the MSA played through it at the next practice session. We didn't even get through the first song before I had to stop, it sounded terrible. I tried adjusting the tone controls, and several other settings, to no avail. Initially I thought the problem was with the new Quilter amp, and was prepared to send it back. I had my gigging guitar in the car, so I quickly set it up and got through the practice session.

When I finally had a chance to investigate the problem further at home, I determined that the GFI U12, my Carter U12, and my Sho-Bud D10 Permanent all sounded great played through a Fender Vibro Champ, Peavey NV400, and Quilter MicroPro Mach 2.

So, then I tried the MSA through the Fender Vibro Champ, Peavey NV400, and Quilter MicroPro Mach 2. The MSA was equally awful through all three amps. It was "ok" when the lower strings were picked. However, when I picked any of strings 1 through 4, or included any of them in the grip with lower strings, it was extremely shrill and tinny.

My suspicion is that the E9 neck pickup has a problem. I don't use the C6 neck, and not sure if it has been affected or not. Unfortunately, I don't have a spare 10 string pickup that I could swap out, unless the C6 pickup could be used on the E9 neck.

Having said all that, I have a couple of questions and need some help/guidance/advice. I'm not very knowledgeable of electronics or electrical stuff, but I do understand a few very basic things about them. I do have a low quality volt-ohm meter, and almost know how to use it with some guidance.

1) Before buying a pickup, are there any readings I can take to see if the E9 pickup is healthy or not?
2) Would the C6 pickup be useable on the E9 neck, either for diagnostic purposes, or temporarily to see if the shrill/tinniness goes away?
3) There's not much more than the pickups. Although, there are the pickup leads, the toggle switch to select the neck pickup to use, and the output cable jack. Those appear to look ok, no loose or extraneous frayed wires.

Any help/advice/guidance/etc. will be much appreciated!

Thanks,
-Chuck
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GFI U-12 Ultra Keyless, Carter Black U-12, both with Alumitones, and a sweet '70 Sho-Bud Permanent D-10, NV400 in Rick Johnson cabs, NV112, '73 Vibrosonic in Rick Johnson cabs, Hilton pedal, Steeler's Choice seat, Bessdang Gizmos from Dale Hansen, and a few other widgets and doodads.
I may not sound good, I just don't wanna sound bad.

Bob Hoffnar · From: Austin, Tx

Chuck, before you spend any money I would go over the wiring. I had the same problem this summer with an Emmons and it turned out to be a cold solder joint. Pickups tend to work or not work. But all sorts of goofy stuff can go wrong with even the most simple wiring.
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Bob

David Ball · From: North Carolina High Country

I had a Rickenbacker do that to me--the pickup worked, but all of a sudden sounded really tinny. The other neck sounded fine.

If you set your pickup selector to the E9 neck, plug a cord into the guitar and then take your ohm meter and measure between the tip and the barrel of the other side of the cord, you should read something in the Kohms range. If it measures less than K ohms (not knowing your pickup, I can't say how many K ohms, but it shouldn't read like 10 ohms or something like that), or if it reads really high--hundreds of Kohms or more, or reads open altogether, you're probably looking at a rewind job on that pickup. Although it could also be in the wiring harness somewhere else as Bob pointed out.

My Rick pickup read completely open, but still worked somewhat. Just tinny and thin. It had a wire inside the coil broken and I got Tom Brantley to rewind it for me.

As Bob says, a bad solder connection somewhere is a likely culprit too, and easy to fix.

Hope this helps--haven't finished my first cup of coffee, so this rambling might not make much sense!

Dave

Donny Hinson · From: Glen Burnie, Md. U.S.A.

Chuck, unless someone has changed them, the E9th and C6th pickups are identical, as they are on most all (unaltered) double neck guitars.

Bill Sinclair · From: Waynesboro, PA, USA

When a pickup coil opens somewhere in the middle of the winding, the two separated coils can act like the plates of a capacitor which will still pass a signal, just not the low frequencies. Try the measurement that David Ball described and let us know what you find. And yes, I highly recommend Tom Brantley if you need a rewind.

Jim Palenscar · From: Oceanside, Calif, USA

In my experience, when that happens most of the time the pickup is shorted to itself and you will not be able to get a reading on the ohm meter(which generally is 15-18k). On the earlier MSA's single coils were used and are quite thin physically making it difficult to find a suitable drop in replacement. I probably have a couple at the shop if needed.

Michael Brebes · From: Northridge CA

This is how I would troubleshoot it:
1) Does the pickup on the C6 sound the same as the E9? YES - probably a cold solder joint somewhere between the switch and the output connector. NO - either cold solder joint at switch or wiring is open in the pickup.

With the switch set to C6 neck, measure the resistance between the two wires coming from the E9 pickup. It should measure somewhere between 10K and 20K ohms on a digital ohm meter. If it measures high then there is a break in the coil of the pickup. The pickup can be rewound since finding a replacement that size could be difficult.
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Michael Brebes
Instrument/amp/ pickup repair
MSA D10 Classic/Rickenbacher B6/
Dickerson MOTS/Dobro D32 Hawaiian/
Goldtone Paul Beard Reso

Mesa Boogie Studio Pre/Hafler 3000
RP1/MPX100

Chuck Snider R.I.P. · From: West Virginia, USA - Morgantown, WV

Yaaay! Problem SOLVED!!! Thanks to everyone for your great ideas to help!!! I had previously talked to Jon Light about this a month or two ago, but at the time I didn't have enough time to look closely. Jon's ideas were very similar to to the suggestions from Bob Hoffner, David Ball, Bill Sinclair, Jim Palenscar, and Michael Brebes. So, I started by taking a very close look at the wiring and solder joints. First I had to unmount the switch and output jack to be able to clearly view the wires and solder joints. I also removed the screw anchoring the ground leads.

Here's what I found:

1) The lead to the output jack was a cold solder joint, so I re-soldered that.
2) The ground wire from both pickups had been anchored under a frame screw by merely stripping some of their insulation, placing the wires under the screw and tightening the screw. To correct that, I soldered a proper connector to the ground leads from the pickups, and then anchored the connector under the frame screw.
3) The signal lead from the E9 pickup had a couple of suspicious spots that had been mashed/crushed partially exposing the wire. One of them had apparently been badly repaired, and was likely the main cause of the problem. So, I cut out the mashed/crushed spots, then spliced and soldered those spots. I added some heat shrink tubing on most of that lead covering the splice joints.

I'm not certain which of those was the actual cause though likely #3 was the worst, and the other items I found added to the problem.

Jim Palenscar - I'll call you about those replacement pickups, I may spring for one of them as a spare. I also want to get some tuning nuts for the MSA, and I want to make sure I get the correct ones.

Thanks again to everyone that responded, it was very much appreciated!!

-Chuck
_________________
GFI U-12 Ultra Keyless, Carter Black U-12, both with Alumitones, and a sweet '70 Sho-Bud Permanent D-10, NV400 in Rick Johnson cabs, NV112, '73 Vibrosonic in Rick Johnson cabs, Hilton pedal, Steeler's Choice seat, Bessdang Gizmos from Dale Hansen, and a few other widgets and doodads.
I may not sound good, I just don't wanna sound bad.

Jon Light (deceased) · From: Saugerties, NY

Chuck -- when I saw your post here on Saturday I thought 'oh damn....I thought we had solved this!' Without going back and rereading our messages I remembered that the only problem we solved was ruling out the Quilter as the culprit (a critical issue with the countdown clock for returns ticking).

Glad you finally got at this and ¡fantastic! that you've troubleshot & fixed it!

Bob Carlucci · From: Candor, New York, USA

The most common basic step in any low voltage DC wiring system is the "wiggle test"... So many problems in low voltage circuits are caused by bad solder joints, degraded connectors,corrosion, frayed wires, etc.. The wiggle test often finds these kinds of problems in very short order.
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I'm over the hill and hittin'rocks on the way down!

no gear list for me.. you don't have the time......

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