Question about an Epi SG selector switch, push/pull knobs, and p/u effects

[living room rocker]

I've a question regarding the push/pull volume controls and selector switch function on a recently purchased Epiphone SG 400 Pro. With the 3-way selector in the up position, this energizes the neck pickup while its push/pull volume knob splits the neck humbucker into a single coil. Likewise, with the 3-way selector in the down position, this energizes the bridge pickup while its push/pull volume knob splits the bridge humbucker into a single coil. It is the middle position of the selector switch, along with each push/pull volume knob position that has me confused. If I select the middle position 3-way switch, pull up BOTH volume knobs, roll down the volume knob of either to zero, this kills all sound. What's happening?

 

[Worblehat]

That's how it is wired. Astonished me at first, too.
Having the selector switch in the middle position you can use the volume knobs to blend the neck and bridge pickup to your taste. But as soon as one of the volume knobs is at zero, you won't get sound from any of the pickups.

I don't have a coil tap function on my guitar but I guess pushing or pulling the volume knobs does not change this behaviour. Does it?

 

[Bad Penguin]

it's normal, so relax. And welcome to the forum!
First off, the push/pull switches are what's called coil taps. Basically, it grounds one half of the pickup to make it into a single coil. ( Like on a strat.) So when you pull both up, and have the middle position on the 3 way, you have 2 single coil pickups.
The way the guitar is wired, if you turn the volume down to zero on either pickup, when the switch is in the middle position, you effectively turn off the sound of the guitar. This is completely normal. It's been this way for over 50 years, and nothing to be concerned about.

 

[Adavis84]

Yep, perfectly normal. Turning a volume pot to zero sends the signal to ground. When the pickups are in parallel (middle switch position) and one pot is at zero, you've provided a ground path for the sum output of the two pickups. There are wiring schemes that get around it, but they're not worth the trouble from my view.

 

[living room rocker]

That's how it is wired. Astonished me at first, too.
Having the selector switch in the middle position you can use the volume knobs to blend the neck and bridge pickup to your taste. But as soon as one of the volume knobs is at zero, you won't get sound from any of the pickups.

I don't have a coil tap function on my guitar but I guess pushing or pulling the volume knobs does not change this behaviour. Does it?

You're correct Worblehat, now that I've checked. Regardless whether the push/pulls are in or out, rolling either to zero with the selector at mid-position kills all sound.

 

[living room rocker]

it's normal, so relax. And welcome to the forum!
First off, the push/pull switches are what's called coil taps. Basically, it grounds one half of the pickup to make it into a single coil. ( Like on a strat.) So when you pull both up, and have the middle position on the 3 way, you have 2 single coil pickups.
The way the guitar is wired, if you turn the volume down to zero on either pickup, when the switch is in the middle position, you effectively turn off the sound of the guitar. This is completely normal. It's been this way for over 50 years, and nothing to be concerned about.

Thanks for the welcome and info Bad Penguin. I'm fairly new to guitar playing and have recently discovered the tonal effect differences with just simple volume adjustments. Kept dialing down the bridge volume with the neck volume maxed and it killed all sound at zero. I've found that adjusting volume and tone pots can give oneself an almost unlimited array of tones. Why do guys invest so heavily with pedals?

 

[living room rocker]

Yep, perfectly normal. Turning a volume pot to zero sends the signal to ground. When the pickups are in parallel (middle switch position) and one pot is at zero, you've provided a ground path for the sum output of the two pickups. There are wiring schemes that get around it, but they're not worth the trouble from my view.

Thanks for the input Adavis84. That makes sense, and I agree will prolly just leave it be as is.

 

[plankton]

I've found that adjusting volume and tone pots can give oneself an almost unlimited array of tones. Why do guys invest so heavily with pedals?

Because they're so much fun! Also, guitar controls can only affect your signal by taking things away (unless you have active pickups) while pedals can add all sorts of cool stuff.

But you're right, using the guitars controls is a great way to produce a huge variety of tones, especially coupled with a good tube amp. Throw a germanium fuzz into the mix and I'm in heaven!

My Laney Cub is a single channel amp and I keep the gain set for mild breakup (think AC/DC). Dialing back the guitar volume gets me a great clean sound, and with two volumes set at different levels a simple flick of the toggle changes between them. Step on a fuzz or boost pedal and you can dial up any level of dirt you like.

 

[Bad Penguin]

Like Plankton said, pedals are fun! You can only adjust your guitar tones so much. Throw in a chorus or a nice distortion/gain/drive pedal, then a bit of delay and reverb, and you are exploring new sonic territory.

 

[Col Mustard]

Welcome to ETSG!
If you're new to all this, you're in the right place to ask questions and
get honest answers without too much horsing around.
I agree wholeheartedly with much of what's been written here:

Including your observation that a whole lot of tonal control is available right in the pots
your guitar is equipped with. If you think about it, the Gibson Les Paul was invented in like
1950-1951. There were NO pedals then. The Gibson guitar with two P-90 pickups and
individual tone and volume controls for each one was a radical improvement on
the older Jazz guitars that players had to use.

So the control layout was designed to do just what you've observed. To give the player a lot
of tones to use in his music, and it worked very well at the time. And it still does. Many members
here refuse to use pedals as an aesthetic stance, and demand utmost performance from their
instrument as it is, and from the amp they plug into. And they get it, even in 2018.
Gibson and Epiphone SGs and Les Pauls are very versatile right out of the box, as designed.

But the rest of us love to enhance all this with all kinds of little boxes full of magic.
For me, the joy is in having so much control at my feet, so I can stomp a pedal without
the audience being aware of it... and without having to look down and touch the right knob.
Here's a relatively simple pedal board... I'll walk you through it:

Signal goes from right to left...

1. stomp tuner... the instrument plugs in here. Stomp the pedal and it mutes the signal
so you can tune your guitar and see the notes in a nice bright LED
without annoying the audience, or your band mates. Stomp it again and you're live.

2. EQ pedal... seven frequency bands to either boost or cut. You'll read lots of posts from
guitarists who complain that one pickup or another is "muddy" or perhaps "shrill"...
People who post comments like that don't own an EQ pedal, or don't know how to use one,
or simply refuse to consider it, claiming that it degrades the signal.
>I like having one of these on my board.
I don't use it all the time, because I have never owned a guitar that sounded
either muddy or shrill (to me). The guitar pickups I have experience with have all been accurate.
So sometimes I use the EQ pedal as a clean boost. To me, that's an excellent function, and well
worth having.
>Every musician needs to know how to listen to Highs, Mids and Lows...
and this pedal is a good way to study this skill.

3. Overdrive... The Blues Driver adds distortion to the clean sound of a fine Gibson or Epi.
It simulates the effect of playing an amp so loud that the vacuum tubes built into it can't handle
the pressure and distort the signal. (except you don't have to damage your hearing if you use
the pedal). Do you begin to get it? The distortion effect add so much interest to the clean tone
of your guitar, that simulating it has been the goal of pedal makers ever since the sixties.
There are now lots of distortion pedals you can buy, I like the Blues Driver.
The pedal gives you control over how much distortion to add to your signal,
and you can turn it on and off with your foot. Stomp it for your solo, return to the mix afterwards...
Hard to beat, and very valuable for a gigging guitarist.

4. Reverb... This is just another enhancement.. many amps are equipped with a reverb unit,
but this little red one sounds as good or better than most IMHO. It's a tone I use a lot and
like a lot, and I can turn it on or off with my foot.

5. Direct box... this sends the signal to a P.A. mixing board using an XLR cable which avoids
signal degradation from long cable runs. I use mine to send the signal to the board, but also
to send it to my amp behind me. Very useful IMHO. Others prefer to mic the amp, wanting
the tone of the amp as their final sound. They don't need the direct box then, but put a mic
on the amp and send that signal to the board.

Lots of choices and preferences here... and that's why we love to mess with all
these little boxes.

PEDALS ARE FUN...

 

[Dave Johnson]

As things are now your volume pots are wired as so...

Independent wiring will eliminate what you experienced. This way one pickup can be turned all the way down
with out affecting the other one. It's as simple as swapping two wires on each volume pot if you choose to
go this direction.

Diagrams courtesy of StewMac.

 

[DrBGood]

I've found that adjusting volume and tone pots can give oneself an almost unlimited array of tones.

Is there a good tone difference with all pots at 10, between neck by itself and middle position ? Or do they sound pretty much the same ?