Need help with wiring of my pickup

[Chinn]

I finished my little BluesBird emando last fall built from components from Moongazer Music (pickup, neck, bridge).

Wonderful little instrument and exactly how I hoped it would turn out when I designed it.

On a negative note, I've never gotten much adjustment at all out of the tone knob, and the volume knob only works at the very last 30 degrees or so of rotation.

The pickup is an Almuse MG4, and its wired for coil tapping. I do get nice varied sounds from each of the 3 positions on the switch- 1st position gritty and complex, 2nd position clean with very little edge, 3rd position same as first but with a little more bass and less treble (pretty slight differences though betwee 1 and 3).


Tom Morici at Moongazer provided this wiring diagram and I wired it to the diagram as far as I can tell.


I realize this is pretty hard to interpret, but this is the back of the pickguard and the wiring I did.




If I remember right, when I wired up the mando, I did verify that one of the pots was a volume pot, and the other a tone pot.

[Tom Wright]

A couple of questions: Do your knobs act clockwise--more, counter-clockwise less, i.e. normal? The diagram and your picture seem to show a reversed setup. The center tab is the wiper of the pot, the rotating item. It doesn't matter if you go in at the wiper (Steve doesn't on my Ryder) or one of the outer tabs, but when turned fully clockwise, the wiper has to be at the output tab for normal setup. Yours looks the opposite, in that for the wiper and output to meet, it has to be turned counter-clockwise. This applies to the diagram, too, so I'm baffled.

As to the response, that might be an issue of not ideal values, or not audio-style pot. (I like at least 250K.) There might be an "A" somewhere on the case of each pot if they are audio-taper. Linear-taper will be unsatisfying. Make sure the grounding of the tone pot is good, so the capacitor shorts to ground effectively. (That is how those work, the cap allows highs through and the tone control dumps the highs to ground.) If it is not shorting completely, the effect will be very slight. Cook the case good with the iron and add a bit more solder.

[Soundfarmer Pete]

Hi Chinn,
Worth checking the values....I recommend 500k pots and a 473 capacitor.
Since your volume control is acting like an on/off switch, it sounds as though you are using a log (audio taper pot) for volume - for best results, you need a linear (B500k) for volume and a log (A500k) for tone.
The 473 capacitor should give plenty of treble cut - if you find it a bit extreme, you could go for a 333.
Have fun,
Pete

[Chinn]

Thanks for the suggestions ya'll.

Pete, I think I'll pull the pickguard and check the pots. I thought I had the right type, but maybe not. Will try those different caps as well.

[thistle3585]

With those pickups, but using a different wiring diagram, I use 500K audio pots on both volume and tone with a 022 capacitor and sometimes using a 047. Based on your photo, I wonder if the "legs" of the capacitor might be touching something else as it seems to be making quite a stretch to its two contact points.

[Chinn]

Andrew, thats a good question. If you look closely at the legs of the cap, I put some 1/32" heatshrink on them to prevent just that.