NS X175 tone control = no change ?

[JohnW63]

I was going to do a short post comparing my pretty new Newark St. X-175B and my new to me, SF4. I plugged them both into this small practice amp that is pretty neutral in tone. As I started to twist the dials on both, to judge the range of tones each had, I found the tone control, for the neck pickup, on the 175 does next to nothing. The bridge pickup actually effects the sound so that I am my kid could hear a change, the neck does either VERY little or nothing. Am I missing something in how these tone controls are wired or did I just find a defective one ? You may very well ask, " How did you never pick up on that issue after all these months ? " and the answer is, " I always turn all four knobs to 10 and change things on the amp. "

 

[B Arbogast]

If it's like my Capri, then the tone controls use "50s wiring."
Wired that way, the tone controls work as expected with the volume controls on 10.
But with the volume controls rolled back, the tone controls work in a non-intuitive way (to me anyhow!).

I find "50s wiring" for tone controls mostly useless.
However, there is one thing it is very useful for:
set the tone control to around 6, and you won't hear any treble loss as you roll the volume control down.
I think that's a great feature.
But I still miss having a full range of usable tone control settings.
(Of course, I may just be using the control in the wrong way.)

 

[Sleeko]

Good post. Compared to the tone controls on my other guitars, the Guild's is quite mild. You can hear a difference but it's not obvious.

 

[JohnW63]

But only on the NECK pickup ? On my Starfire, it's obvious. On the NS X-175 is might as well not have a knob.

 

[SFIV1967]

John: I just looked how the guitars might be wired. I am not an expert to say which is better however, I just post the below as maybe others can explain the differences.

Your second half 90ies Starfire 4 might be wired like below (I think that was the last wiring diagram on the Guild webpage some years ago). It is almost impossible to check on the Starfire 4 as it is hard to find such small mirror to check the pots and connections.

I also found the Newark St. X-175 wiring harness:
The left two pots are the tone pots, the middle lug is grounded, one is open and the white wires go to the right two volume pots, obviously hidden under the black sleeves in the middle are the two capacitors in the white wire.
That white wire with the capacitors from the tone pots go to the middle lugs of the volume pots and from there to the 3 way switch.
The red pickup (hot) wires go to one outer lug of the volume pots, the other outer lug is grounded. The black wires are ground wires.

It I am not mistaken in general the NS X-175 is wired like this below '50s type wiring (disregard the 200kohm pot below and also there is no direct ground wire between the tone and volume pot lugs, the ground runs differently):
You see the capacitors are connected to the switch. (and I would think both capacitors in the NS X-175 are 0.022uF)

This below picture is the same circuit (minus the direct ground wires from tone to volume lugs):

Ralf

 

[JohnW63]

I had to put all three up on the screen to make sure I didn't miss anything. I think I may have to draw it out form myself to analyze the three schematics, but even with the differences of how the signal passed through the volume and tone controls, I don't see any difference , in each drawing, between the neck and bridge pickups. So, I would expect the SAME effect on both when I twist the knobs. Maybe Default or GAD can correct my thinking.

 

[B Arbogast]

You should get the same type of response on both the neck and bridge settings. If not, then something must be wrong. A broken wire perhaps?

 

[SFIV1967]

I don't see any difference , in each drawing, between the neck and bridge pickups.

John, you are totally correct, I just wanted to tell you why your Starfire might behave different (assuming it is differently wired) from the NS X-175, it had nothing to do with the issue you seem to have on your NS X-175. Sorry that I confused you.

A good general tutorial I sometimes use to look up about guitar electronics is this:
http://www.stewmac.com/How-To/Online_Resources/Pickups_and_Electronics/Understanding_Guitar_Wiring.html
http://www.stewmac.com/How-To/Online_Resources/Pickups_and_Electronics/How_a_tone_control_works.html

Ralf

 

[JohnW63]

It looks like I need to pull a pickup out to get access to the innards of the guitar and use lights and mirrors to see what going on. I wonder if there is enough slack on the cables to get the tone control out and put a meter on it without pulling the volume control as well ?

 

[SFIV1967]

I wonder if there is enough slack on the cables to get the tone control out and put a meter on it without pulling the volume control as well ?

No John, that is not possible. Look at the construction of your guitar and look at the harness picture above. Sure, the pictup is easy to remove as it is just plugged in and not soldered. But look how small the hole is that you gain when the bridge pickup is removed, you can't get your hands in there. And if you unscrew the tone pot and it falls in the body you will never get it back mounted in the hole! To remove the harness/pots you really need to use aquarium tubing, no other way really. (Sure dental floss also works but is much more difficult). Aquarium tube is the same what New Hartford used in their production as well for the American Patriarch models. But if you have never done it it will be very tricky.

Have a look here: http://www.letstalkguild.com/ltg/sh...(assembled-)&p=1531822&viewfull=1#post1531822

And this was the New Hartford American Patriarch electronics assembly desk: https://scontent-fra3-1.xx.fbcdn.ne...24_10203760725554592_726910489187612580_o.jpg
See the tubing used in that X-500 to mount the 4 pots?

Ralf

 

[Quantum Strummer]

The first thing I'd suggest before taking the guitar to a luthier (the second thing I'd suggest) is to plug into your amp, crank the treble, center the mids & minimize the bass (or at least as much of this as the amp allows), then play while fiddling with the suspect tone control. If the pot & cap are doing anything this should let you hear it.

The first time I ever played through a Marshall 1958 amp (18 watt combo, two 10" speakers) I was using my Fender Jaguar. I like to use the Jag's "strangle" switch (cuts low end) for clean, chordal rhythm playing. In this case when I flicked the switch I couldn't hear any change in the sound. So I thought the switch had cr*pped out. Back at home I plugged into one of my own amps et voilà!, the switch worked again. Turned out the 1958's bass response, or lack thereof, was the culprit.

-Dave-

 

[JohnW63]

Geez. I thought that being a hollow body there would be space to reach inside. Now I want to see a video of someone building one of these guitars.

 

[JohnW63]

I hooked it up to an acoustic amp, al be it a small speaker version, but it is a clean tone. If I strum, and then twist the knob, I can hear a change. I can't tell you what is changing specifically. It seems to "ring" more with it all the way up. Could it be more high end or midrange ? Perhaps. Maybe I just need to slap some new strings on it and see how it changes.

 

[B Arbogast]

Did you do the experiment with the guitar volume all the way up? The tone controls really act in unexpected ways (to my ear, at least) with the guitar volume turned down.

 

[JohnW63]

Yeah. Full volume. I'll have to look up the combination of the 500k pot and a 22uf cap to see what frequency would be effected by changing the resistance. That might help.

 

[JohnW63]

Update:

New Chrome strings = PLENTY of tone change ! I don't know if it's the "new" part or the "chrome" part, but it is night and day now.

 

[B Arbogast]

Excellent! Problem solved, then?

 

[jcwu]

Update:

New Chrome strings = PLENTY of tone change ! I don't know if it's the "new" part or the "chrome" part, but it is night and day now.

Maybe there just wasn't much treble to roll off with the old strings?

I have a '57 T100 that had a non-functional tone knob. Roll it this way and that, no change. Well, yesterday I plugged it in again, and voila! Tone knob roll takes out the treble. What changed? I have no idea. It just started working, and I'm happy with that.

 

[JohnW63]

With a 1957 instrument, I can imagine that could happen.

I may try it out on all of my amps to see if their response was part of the problem.