Kick's first build LP-1MQ Red Widow

[Simon Barden]

Kick, you will certainly want the volume pots as 'A' types. Its the tone pots that can be audio or linear taper, depending on personal preference, but the volumes need to be A type or you will get a very sudden drop in volume as you adjust the knob. With an audio taper pot, the resistance at 50% travel is roughly the same as the resistance at 10% travel on a linear pot. So you'd set the volume on 5 with an audio pot to get the same reduction in output as turning down from 10 to 9 on a linear pot.

Easy enough to undo the pots so you can get the harness out and look at them. The A and B are normally printed on the insulation that the 3 tabs are connected to on the shaft side of the pot (so you can't see from the back without taking the pots out of the guitar).

If they aren't swapped over, then you can take the opportunity to get some good photos of the wiring.

[Andy40]

Kick, you will certainly want the volume pots as 'A' types. Its the tone pots that can be audio or linear taper, depending on personal preference, but the volumes need to be A type or you will get a very sudden drop in volume as you adjust the knob. With an audio taper pot, the resistance at 50% travel is roughly the same as the resistance at 10% travel on a linear pot. So you'd set the volume on 5 with an audio pot to get the same reduction in output as turning down from 10 to 9 on a linear pot.

Easy enough to undo the pots so you can get the harness out and look at them. The A and B are normally printed on the insulation that the 3 tabs are connected to on the shaft side of the pot (so you can't see from the back without taking the pots out of the guitar).

If they aren't swapped over, then you can take the opportunity to get some good photos of the wiring.

Hi Simon,

True about the A and B pots. personally I prefer all audio pots. I dont think thats Kicks problem though. have a look at his wiring picture on page 30 and see if you can see a problem. To me (amateur) I don't think that hes earthed the pots properly

[chrissyinbkk]

Think Andy is right, to my even more inexperienced eye for a start the earth is missing between the neck volume and tone pots

[Simon Barden]

He has. Purple wire between the neck and bridge volume pots, blue wire between bridge volume and tone and green wire between bridge and neck tone pots. You don't want a fourth ground wire between neck volume and neck tone to create a loop. It's not as the diagram, but they are all connected and its all good.

As long as the output ground is connected to one of those pots, then all should be fine. The solder joints, whilst not the neatest I've ever seen, all appear to have flowed across the surface of the pots and aren't blobby and suspect.

What I'm not 100% sure about are the three yellow wires soldered to the back of three separate pots as I can't see where they go.

[Kick]

Haha, thank you all for thinking with me and I know my soldering is not 'state of the art'

About the three yellow wires; the one connected to the neck volume is the earth from the bridge. The wire from the bridge tone is earth for the jack and the last one from the bridge volume is earth for the threeway switch. But I must admit, that is what I think it is. I have open it up to see it.

As said before, I followed each and every steps from the video tuts from PBG.

And what others say about 'tapers'. I don't know what you mean by a taper (now I feel really stupid...)

What if I just unsolder the nonfunctional pots and switch them? And am I able to see then if there is a 'a' or 'b' stamped on them?

I shall make some new pictures this weekend!

[chrissyinbkk]

You can see it Kick...

[Simon Barden]

A 'taper' is just the shape of something that goes from thin to thick, or thick to thin. In this case it's the shape of the resistance curve of the potentiometer as it's turned. Just another word for 'curve'.

Here you see three curves/tapers for different characteristic pots. The coloured lines are the more realistic values, the dotted lines are the ideal curve. You can get pots where the real-world curves match the idea curves but the cheaper pots tend to use two strips of different resistance track to make up a log (or anti-log) pot.

[Kick]

Thanks Chrissy and Simon!

Here I have an image of how it is at this moment:



I was right when I explained the three yellow wires. And as far as I can see everything is connected as it should be. I think I'm gonna unsolder the two pots that are not working correctly and switch them. I only have to find some time...

[Simon Barden]

I'd still just remove all the pots and look for the A and B labels before thinking about swapping them. If the A pot is volume, then it might be damaged.

I'd recommend pulling the pots out anyway, so that there's no danger of any bits or wires on the pots touching the cavity foil and then playing and seeing what happens.

When you tested the pots, did you test the volumes when neck only and bridge only were selected, or when both pickups were selected? Helps to know if both were selected as there could be interaction between the two pickup circuits, but if it was bridge or neck only, then there shouldn't be any and its down to the pots or the wiring.

Let us know if the problem still happens with the selector switch in the neck position, the bridge position and the both pickups on position. Note that in the 'both pickups on' position, you'll get no output at all if the other pickup's volume is turned down to 0 and some noticeable interaction if it's only just above zero. So test each pickup when individually selected first, then try them both together to see if the behaviour is different

[chrissyinbkk]

Wish I had read that 2 hours ago Simon.......