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mallynoshow
05-09-2017, 06:35 PM
Evening all,

first build, and this weekend i'm hoping to do the pups.

Question - the online PDF shows the pups coming in from the left side into the control cavity. The IB-5, when looking into the cavity has the wires coming in from the right. I've flipped the PDF below, and am wondering which one should I use? Does it matter as long as i follow the same pod connections but in reverse? Or should I feed the pups in through the right and attach to the left pod as per the original PDF.

Any advice would be greatly appreciated.

22098

22099

Simon Barden
05-09-2017, 07:32 PM
It doesn't matter which side the pickup wires feed in from - it's a wiring schematic, rather than a true physical layout (though I know that having everything positioned as it's laid out does help). But it does matter which of the three potentiometer lugs you connect your wires to and you can't just mirror-image the connections.

If you swap them over, then the knobs will operate in reverse - so that 10 is off and 0 is full volume or tone. Also, with the volume pots, as they have a logarithmic curve which would normally give a nice gentle reduction in volume (as the ear hears volume in a non-linear way), working backwards they'd give an anti-log function so all the volume would be with the knob on 0, but by the time it got to 1, you'd have almost nothing.

So please do wire the pots up as shown in the PBG diagram, just ignore the side the pickups feed in from.

Note that the pots are also laid out on the bass in a diamond formation, and not a square one as shown in the schematic, so you'll have to decide which pot is going to go where. It's the connections to and between the pots and outputs and switches and pickups that are important, not the relative component locations.

It's easier to make up the main wiring harness outside of the body, by using a cardboard template with holes (in the correct locations) in for the pots to sit in whilst soldering them up, then just make the last couple of connections to the pickups when the pots are fitted in the cavity. This helps to keep wiring lengths down and you get a neater cavity as a result.

One consideration for the future is that a lot of people have fitted the Belcat EQ-B2T 2 Band Active EQ in their IB-5s, which gives a master volume, balance pot and treble and bass controls. It gives a slight boost to the output signal for the standard kit pickups, which people generally find to be a bit low on that model. You can fit one at any time, so no rush to fit one straight away.

mallynoshow
05-09-2017, 07:46 PM
Simon, you've saved what little hair i have left. FWIW, I was thinking of going with your idea of just feeding in through the right but following the top diagram.

Greatly appreciated!!

Simon Barden
05-09-2017, 08:07 PM
Hope it all goes OK!

mallynoshow
10-09-2017, 09:30 AM
Right. I know I'm close. I'm getting full sound and tone after finishing the soldering.......BUT only when the plug is half in! This has got to be an easy fix, right?

Anyone, please?

wokkaboy
10-09-2017, 09:37 AM
Mally its a stereo jack, so try moving your wires to another lug/s on the jack maybe. Once you experiment and get the right ones solder them. Your jack has 3 lugs ? Or is the jack tip shorting on copper shielding or anything else ?

mallynoshow
10-09-2017, 10:07 AM
Thanks Wokka. It has 3 lugs but the cable that comes with the kit appears to be a mono cable. Not sure whether this would cause an issue or not. I'm starting to think maybe the plug itself might be damaged. I've tried all different combinations of wiring but still no luck.

*edit. I have been doing some continuity checks on the jack. It is giving 2 positive results when testing the outer on the plug (earth). see below. I'm beginning to think there may be a short in the plug itself.

22165

Paul_H
10-09-2017, 12:01 PM
It it probably more correct to refer to the socket as a Tip Ring Sleeve (TRS) socket, rather than stereo. The guitar plug is a Tip Sleeve (TS) plug.

When you plug in, the Tip part of the plug initially engages with the Ring part of the socket. Push the plug further, and the Tip components of the plug and the socket will connect. If you have soldered the output wire from the guitar to the Ring connector, this would explain the issue you are having.

In the barrel style of socket, it is practically impossible to visualize what is going on, but this image may help. You can use a TS plug in a TRS socket by leaving the socket's Ring connection unattached.

22166

Paul

Paul_H
10-09-2017, 12:04 PM
In the event that the socket has a problem, I recommend that you purchase a quality replacement. Switchcraft brand is great, and you can get one here:

https://www.realparts.com.au/electronics/jacks/switchcraft-stereo-long-barrel-jack-black.html

This is a TRS socket, so earlier comments apply.

Paul

mallynoshow
10-09-2017, 02:44 PM
Thanks Paul. I've ordered a replacement just to eliminate that as a problem. I continued to try different combinations of wiring with the existing socket and found the only time it sounded perfect, was when i wired it to T and R and left S disconnected. Sounds bizarre, but everything else essentially gave me no signal. It does however seem to be causing the neck VP to act like a master volume with nothing coming from the bridge unless the neck is turned up.

Paul_H
10-09-2017, 03:24 PM
If you've not removed the socket, are you able to provide a clear photo of your wiring? Not sure, but it sounds like something else might be involved.

stuzl873213
10-09-2017, 04:46 PM
Sounds like that

mallynoshow
10-09-2017, 04:57 PM
Thanks Paul. Photos attached. On a side note, just to make the day a little more frustrating, two cover plate heads sheared off while i was tightening them - by hand.

I insulated the red/white with black shrink. The rest, i followed the above diagram. Again, the guitar sounds and plays great, it's just I suspect something is a little sketchy.

Love to know your thoughts.

22175

22176

22177

22178

Paul_H
10-09-2017, 06:11 PM
I confess I'm having difficulty seeing everything. Check for solder bridges between wires, terminals, etc, on all pots and the jack. Use a magnifier to see clearly, and/or use a continuity or ohm meter to confirm or exclude.

Is a green wire from a pickup twisted around the shield material? If so, check that the green insulation hasn't melted from soldering.

If you can get in closer with the shots (maybe use a tripod?) it will be easier to examine.

I feel confident that you will get this sorted. Many issues arise from bridges, shorts, or grounding issues.

Bummer about the screws, by the way.

I routed around the cavity on my IB-5 so the cover sits flush. That was a nerve-wracking job!

mallynoshow
10-09-2017, 06:35 PM
I confess I'm having difficulty seeing everything. Check for solder bridges between wires, terminals, etc, on all pots and the jack. Use a magnifier to see clearly, and/or use a continuity or ohm meter to confirm or exclude.

Is a green wire from a pickup twisted around the shield material? If so, check that the green insulation hasn't melted from soldering.

If you can get in closer with the shots (maybe use a tripod?) it will be easier to examine.

I feel confident that you will get this sorted. Many issues arise from bridges, shorts, or grounding issues.

Bummer about the screws, by the way.

I routed around the cavity on my IB-5 so the cover sits flush. That was a nerve-wracking job!

I left green/white as they were out off the box. Are you referring to it possibly contacting a wire other than the sheild?

Routing? I feel nervous just thinking about it!

Paul_H
10-09-2017, 07:16 PM
I didn't use the stock pickups for my IB-5, so I wasn't sure about the appearance of the pickup leads.

It is possible to melt wire insulation if the soldering is prolonged, and in paired cables (such as twisted cables) this can sometimes contribute to shorts that are not immediately evident.

Good light and a clear head are your friends for this kind of troubleshooting :cool:

mallynoshow
10-09-2017, 07:37 PM
Agree. Going to let this sit until the weekend. Should have the new socket by then to cross reference whether the issue lies there. Got my magnifying glass and head lamp ready to go. I'll report back.

Thanks again Paul.

Ben Jammin
11-11-2017, 12:26 PM
My son and I have just wired up his MB1 as per the diagram in this thread, and seem to have the problem with the pots described by Simon. I'm certain that we have everything properly connected etc, but I'm a little confused by the 2 terminals in the diagram that seem to be bent back. Are they supposed to be touching the body of the pot, and therefore are ground?
Cheers
Ben

WeirdBits
11-11-2017, 01:37 PM
Is this the diagram (http://www.pitbullguitars.com/wp-content/uploads/pdf/PBG-2Hum4Pot%20v5.pdf) you're using? The two bent lugs/tabs should indeed be soldered to the back of the pot, or you can use a short wire link to the back of the pot rather than bending them.

The volumes need that lug connected to ground, assuming your pot bodies are grounded, so that the volume controls work as voltage dividers rather than just variable resistors. Without the link to ground the volume will never turn down completely, it will go a bit quieter but there will always be sound coming through.

Ben Jammin
11-11-2017, 02:25 PM
Hi Scott,
Thanks for your prompt reply, and awesome explanation. So, we have just earthed the remaining terminals on each of the volume pots, and success! I now have a loungeroom full of Thunderstruck and Smoke On the Water! Happy kid.
Great sounding guitar, thank you for your help.
Cheers
Ben