Author Topic: My MQ - really low output when tapped. Fixed! (Read 5014 times)

Twinfan · « **on:** October 16, 2006, 10:31:30 PM »

My Mississippi Queen arrived today, and is now installed into my Gordon Smith SG1. It sounds great, and I'll post a three way shootout review shortly.

I've got a problem though. I've got a tapped MQ and when the tap is selected, the volume drops REALLY low. I checked and if I roll the volume of the 'full' MQ down to 2.5/10, it's the same as the 'tapped' volume on 10/10!

Is this normal? Have I got a, shock horror, faulty BKP????

Tricalibur · « **Reply #1 on:** October 17, 2006, 01:42:23 AM »

wiring fault maybe? idk, sounds an awful lot like a dimarzio I installed in my stinger strat a couple years back. Come to find out I had it wired wrong from the begining. Sounded better broke anyways tho lol

Twinfan · « **Reply #2 on:** October 17, 2006, 07:51:48 AM »

Nope, I'm pretty sure the wiring is OK:

1) Black and shield (bare) to back of pot.
2) White to hot tag on coil tap pot.
3) Green to tap tag.

I've swapped green and white and that was worse. Has anyone else got a tapped MQ who can comment?

Elliot · « **Reply #3 on:** October 17, 2006, 09:21:50 AM »

I think Sambo had the same problem - you could PM him

Ratrod · « **Reply #4 on:** October 17, 2006, 11:31:01 AM »

What's the DC reading when tapped?

Twinfan · « **Reply #5 on:** October 17, 2006, 12:15:37 PM »

Don't know Ratrod - I have no equipment to check it.

I've spoken to Steve at BKP who said to send it back so they could check it, but that means stripping my guitar down again. I was hoping there would be a simple explanation and I could sort it myself.

I'll try PM'ing Sambo and see what his problem was...

PhilKing · « **Reply #6 on:** October 17, 2006, 12:56:19 PM »

I have a tapped mq. I just get a tone shift with very little volume drop when I switch. I had to check with a multimeter to find the right wiring though (as mine had all 4 conductors the same length).

Not sure if mine would match yours as it was a prototype, but the full output on mine is red (same as the normal HB's). I really don't remember which of the others I used, I would have to get the guitar out - I will check it later if you are still having a problem).

Twinfan · « **Reply #7 on:** October 17, 2006, 01:01:03 PM »

Cheers Phil.

I've checked the old posts of Sambo's problem and he had the same issue at one point. He doesn't say how it got fixed though!

I have everything exactly the same as the tapped Mule in my other Gordon Smith so I can't work out what the problem is. I'll double check it all again, but it sounds like some strange wiring issue as Sambo had the same problem. I've PM'd him to see if he knows what was done to fix his.

I'm hoping the wire colour is the same as a humbucker i.e. black and white are start and finish of coil, so black goes to ground and white to hot tag of push/pull volume pot. Green is the tap and goes to the middle tag of the opposite side of the push/pull 3 by 3 than the white?

Louderthangod · « **Reply #8 on:** October 19, 2006, 03:26:22 AM »

How do you tap a single coil? That doesn't make sense to me.

Twinfan · « **Reply #9 on:** October 19, 2006, 09:15:25 AM »

To tap it, you run a wire out before the end of the coil

e.g. full coil = 6500 winds, tap at 5500 winds.

That way you can get two tones out of one pickup :)

genocidal tendencies · « **Reply #10 on:** October 19, 2006, 09:35:25 AM »

When the new site is ready I really hope it has the difference between coil taps and splits in big bold lettering across the homepage.

Elliot · « **Reply #11 on:** October 19, 2006, 09:35:39 AM »

coil tapping is not to be confused with coil splitting - a split is used to make a humbucker a single coil but a tap drops the active number of winds on the bobbin. You can tap a single and a humbucker - you can't split a single.

Twinfan: Do you know what k reading the full and tapped version gives?

_tom_ · « **Reply #12 on:** October 19, 2006, 12:15:16 PM »

Quote from: genocidal tendencies

When the new site is ready I really hope it has the difference between coil taps and splits in big bold lettering across the homepage.

:lol: Me too. Since I learnt the difference it always annoys me when I see a a coil split being called a tap and vice versa :?

Twinfan · « **Reply #13 on:** October 19, 2006, 02:47:36 PM »

Quote from: Elliot

Twinfan: Do you know what k reading the full and tapped version gives?

Not sure my friend...

Twinfan · « **Reply #14 on:** October 25, 2006, 06:40:28 PM »

Well I sent my MQ back to be checked out and it was fine, so it was down to a wiring issue (which I thought it might be). After an email conversation with Tim and a load of head scratching and wiring research by me I've fixed it!

It's all installed and working perfectly. It sounds great - pretty much the tone I've been looking for! I always knew I'd love P-90s...