Quieting the beast: Problem

[idontgetit]

Alright, I'm glad that there is a forum which could help me out:

I was sick of the strat-noise I got, when I cranked up the gain, so I decided to follow the tutorial...

Shielding went out very well, but I was totally stuck at wiring. My English isn't that good, so I sat hours trying to understand what I have to do...

My guitar has become noisier than ever before, that's why I have to ask some questions:
1. What do you mean by "audio-cable"? I took the white and red one of those: upload.wikimedia.org/wikipedia/commons/9/90/RCA_Connector_(photo).jpg. Hope that was right....
2. How do you prepare the cables? I cut off the outer isolation and the outer wires and just connected the inner wires for "hot" and "ground". Only on the jack I connected the outer and the inner wires of the ground wire, because it was said so. Somehow confused me, because I used just the inner wire on the other side of the ground...I don't get the point of the outer wires anyways....
3. What's a 20# gauge??? You said the inner wire of the audio cable. But why don't you then say, "use another audio cable". I mean, you used only the inner wire of the audio cable for all other connections, so what's the difference to the "20# gauge"?
4. Why don't you use the desoldered wires, for example from the ground loops, but take some special "20# gauge" cable oder audio cables?

I guess it was a piece of cake for all of you guys to get this thing working, but I'm confused....Would be great if we could somehow get my axe working together. I kinda like this whole modding idea and want to learn more about it.

Thanks,
your Idontgetit XD

[newey]

Idontgetit-

Hello and Welcome!

That part of the shielding instructions can be a little confusing.

When the instructions talk about using a 2-conductor shielded cable to go to the output jack, this means 2 individual wires inside a braided wire shield. The conductors connect to the output jack at one end and to the volume pot at the other, as described in the instructions. The braided shield is an extension of the shielding, since it is impossible to get a layer of metal foil through the hole to the output jack.

The reference to #20 wire means a 20 AWG wire. This is a specification for the diameter of the wire. "AWG" means "American Wire Gauge", a standardized measurement. In this case, you want a stranded, insulated wire. This is used to connect the "ground" from the 2-conductor (plus shield) cable to the star ground point. It doesn't have to be #20, 22 or 24 will work fine. You wouldn't want to go any larger than a #20 (#18 is the next size larger) as that's too big and difficult to work with.

You can help us help you by posting some pictures of your wiring, as that may help decipher any wiring problems.

[ashcatlt]

Welcome a'board.

1. For the "audio cable" described we usually use something like a mic cable or headphone cable. Something with 2 wires inside the braided wire shield. What you're using will work, assuming it fits through the hole, but...

2. The "outer wire" is the shield of the cable. It's supposed to catch the noise and send it to ground before it can get to your signal wires. You need to connect both shield braids to "ground" at the jack end. Especially the one that surrounds the "hot" wire.

2. 20 guage is a measure of the diameter of the wire. According to wiki, the actual number has to do with the number of drawing operations required to get the wire down to the desired size. Higher numbers mean smaller wires. The exact guage isn't too important, so long as it's not HUGE, and big enough to work with and not be too fragile.

The audio cable, as I understand it, is for the run through the hole between the wiring cavity and the output jack. That hole is usually tough to shield with foil, so we use the "built in" shield, which you're calling "outer wire". The wiring in the rest of the cavity is shielded by the foil/copper tape/whatever you used for shielding material, and therefore doesn't need the shield braid.

4. I don't understand this question. Can you clarify?

I haven't yet made a guitar noisier by shielding or re-wiring, but it's not particularly unusual for this to happen. It's usually a relatively minor oversight in the wiring, or a less than reliable solder job. We'll help you fix it up.

Can you tell us a bit more about what exactly you did? Maybe post some (well-focused) photos of the guts of the guitar. Describe for us the noise issue as best you can. What does it sound like? What situations cause it? Does it change when you touch the strings or anything else? Does it change with switch or knob position?

[idontgetit]

I decided to rewire the whole thing, because I think that
1. my BIG iron didn't do a good job for soldering
2. I didn't ground the braid shield of the hot wire to the ground of the jack.
3. The wires I used were to weak (too much gauge). Maybe I heard the noise because of a broken wire.

ashcatlt:
I meant the wires, which originally connect the pot-shells. I wondered if you could use them for example for connecting the volumes ground terminal to the ring terminal.


I will buy myself a new iron and do the wiring tomorrow. Of course I will inform you how it works.

Do I really need a ring terminal underneath a pot which connects to my grounding ring terminal? I don't want to build in a capacitor, so couldn't I solder the wire onto the pot shell?

[newey]

The ring terminal is to ensure good contact with the shielding on the underside of the pickguard. Soldering to the pot shell instead will probably work but you may not have good contact with the shielding since you are then relying on the top of the pot shell alone to make contact.

The ring terminal also makes it easier to remove the pickguard, it means one less wire to desolder. You can simply undo the pot to release the ring terminal. Your output jack connections will then be the only ones needing desoldering.

Reusing the wires to the pot shells is OK so long as they aren't bare wires, as used on some guitars. In a shielded guitar, all wires used need to be insulated so they don't contact the shielding.

[ashcatlt]

Feb 24, 2009 12:33:52 GMT -5 idontgetit said:

ashcatlt:
I meant the wires, which originally connect the pot-shells. I wondered if you could use them for example for connecting the volumes ground terminal to the ring terminal.

Yeah, you could use that. Assuming, of course, that it's insulated and long enough to reach where you want it.

Do I really need a ring terminal underneath a pot which connects to my grounding ring terminal? I don't want to build in a capacitor, so couldn't I solder the wire onto the pot shell?

Without the capacitor, you don't really need both ring terminals. Even with the cap, you could just solder the "shield end" of that cap to the pot shell.

Two reasons we usually don't, though:
1) It's sometimes not a lot of fun trying to heat up such a large chunk of metal enough to solder without overheating and causing damage.
2) We want to be sure that there's a good connection to the shielding foil or whatever you're using.

[idontgetit]

One more thing: Do I have to shield the jack cavity? If yes, how is it grounded?

[newey]

No need to shield the jack cavity if you are using the 2-conductor with shield cable to the output jack, as the shielding on the cable takes care of the wires to the jack.

[idontgetit]

Makes sense to me.

Thanks so far. I shouldn't make any theoretical mistakes now .

I'm wiring the beast now and will inform you asap.

[idontgetit]

Hello everybody,
I have good news for you! I got a new soldering iron (which did a much better job) from a friend and wired my baby today, and this time everything seems fine!

I can't exactly tell how much noise reduction I do have now. I have a 15-Watt Amp and on the clean channel on max vol it just very slighty hums. With Overdrive, Max Gain, Max Volume it's still horribly noisy on 1,3,5, but on 2 and 4 it's very enjoyable.

I remember that I was very disturbed by the noise during pauses and this doesn't seem be the case anymore. Guess we can speak of success .

Thank you everyone for your help. I think this will not be the last mod I did .

Your I-Now-Getit ^^

Edit:
Ahh, some questions which came up just now:
1.Does shielding the back cavity (where the springs are) bring you better results?
2.Do you get better sound with thicker cables? The audio cables I used do not have a lot of breads for the inner conductor.
3.In the jack cavity: After you seperate the shield bread from the hot wire for ground, can the hot wire catch significant noise signals in the "breadless" area?
4.When I hold my guitar directly in front of my pc, it starts humming like 50% more. Is this supposed to happen with shielding?

[ashcatlt]

Yay! Glad you got it going.

Feb 27, 2009 20:23:21 GMT -5 idontgetit said:

1.Does shielding the back cavity (where the springs are) bring you better results?

No. Unless you've done something out of the ordinary in there. I was just the other day looking at how I might get a magnetic pickup in there to transduce the sound of the springs. Normally, though, there are no signal carrying wires in that area.

2.Do you get better sound with thicker cables? The audio cables I used do not have a lot of breads for the inner conductor.

No. I use teeny tiny wires out of a MIDI cable. I've heard (read) folks around here talk about the wires from telephone cable, which are likewise very small.

3.In the jack cavity: After you seperate the shield bread from the hot wire for ground, can the hot wire catch significant noise signals in the "breadless" area?

It can, as can the big bulbous "hot" end of the cable and the big bendy piece of metal which it contacts on the jack. Compared to the lengths of wire in the rest of the guitar (especially those really long wires wrapped around the pickups) this is minimal. If you can find a way shield the jack cavity without any of the above-mentioned "hot parts" touching, it wouldn't hurt.

4.When I hold my guitar directly in front of my pc, it starts humming like 50% more. Is this supposed to happen with shielding?

Yes. No shielding is perfect. You'll never get to 0 noise. The computer and it's monitor are by far the noisiest (in an EMI/RFI kind of way) equipment you'll find in a modern studio.

[newey]

Glad you got a good result, IDGI!

1) Unless you are hiding some secret electrical components in your trem cavity, shielding it will make no difference. Only the electronic bits can produce noise.

2) Cables of better quality will help. Usually, the difference is in better shielding. Use as short a cable as you can live with for the least noise.

3) The small unshielded end of the jack wire shouldn't add any noticeable noise. Longer wires make better antennae.

4) Shielding is not a perfect solution. Your goal should be to reduce noise to a tolerable level, not to totally eliminate it. Some environments are particularly "noisy", from an electrical point of view. PCs are a well-known culprit, especially if you use a CRT monitor. So are fluorescent lights and anything with an electric motor in it. You may want to try your guitar/amp in a room without these things to see how much your environment is contributing.

EDIT:And Ashcatlt beat me to the punch, and said the exact same things.

[idontgetit]

@ ashcatlt and newey:

Thanks a lot! I think I will the my guitar the way it is for now as I'm kinda satisfied reading your answers.

I will read myself through the board and see what I can do next .

Regards,
Your Idontgetit