Fishing Controls through F-Holes

Bassamatic · #1 05-21-2010, 02:16 PM

I just got a STEAL on a like new Ibanez Artcore bass. However, there is something funny about the tone control - it does nearly nothing and seems to be almost a mid boost at the bottom. Very weird.

I would like to pull all the controls out and check the wiring.

Anyone have some good ideas about how to get them back into the holes from inside the bass? There MUST be some tricks to this.

Thanks!!

JTE · #2 05-21-2010, 02:52 PM

The controls probably pull through the pickup routes. That's what you do on a Gibson ES-335 style guitar. Before you do it, be sure you're patient and can live without the bass for a few days in case it gets frustrating...

Take the strings off, and remove the pickups. Then, take the knobs off all the controls. Tie some string to each control and to the jack- anything that's attached to the control harness. Label each string with what it goes too, and then tie all the strings together, leaving enough string to make sure you can pull all the guts through the PUP holes.

Then carefully remove the nuts that hold all the controls on the body and slide the nuts and washers up the strings. Then carefully start fishing the controls through the cavity to the routes. Once it's exposed, deal with the issues, resolder/replace what you need to and make sure it all works before you start putting it back together.

To put it back together, GENTLY pull on your bundle of strings, guiding things back into the body in the order they came out. Snug things up, slide the washers and nuts back down the strings and carefully tighten up the nuts.

It's time consuming and can be frustrating so if you have any doubts about being able to do it, take it to a good experienced guitar tech.

John

Pilgrim · #3 05-21-2010, 03:11 PM

JTE is right, of course - most of the time everything goes in & out through a pickup hole.

Some folks have used surgical tubing pressed over the ends of the pots. That idea sounds intriguing to me, since surgical tubing would be a lot more positive and easier to pull than fishing line.

However, the last time I did this, I did the process JTE explained and tied monofilament fishing line around each pot - left plenty of extra line (like 2 feet) so that I could fish them back. Remember to be generous with the extra line - it's cheap.

Expect the fishing line to tangle on itself, and expect pulling stuff through the holes to require patience, dexterity and finagling. It's not hard, but it does require persistence.

Bassamatic · #4 05-21-2010, 05:05 PM

Thanks Guys - I will carefully remove the nuts and attach some string and see where it leads.

I had glanced inside, and the Artcore has a solid stringer running up the middle, so I guess that means that it all goes through the F holes. I would imagine that they have some special tools for this for production that hold the pots in place while the nuts are put on.

Bassman822 · #5 05-21-2010, 05:25 PM

You might want to use aquarium tubing on the pots shafts

Bassamatic · #6 05-21-2010, 05:31 PM

Great idea!

62bass · #7 05-21-2010, 06:33 PM

I have that same bass with the useless tone control. They all seem to be like that. I don't know what Ibanez was thinking. I guess we'll never know. I can't imagine it was designed that way. And I can't see the whole batch of them with faulty wiring. You'd think someone would have caught on.

If you can figure out the cause of the problem, please let us know what it is. There are a number of them in use. I love playing mine. Just that dumb tone control that spoils it. It actually does have a very faint effect when turned down to almost full cut, at least, mine does. You can hear a slight shift in tone, but not enough to be useful.

Good luck with your fix.

Bassamatic · #8 05-21-2010, 07:57 PM

Thanks, 62bass. I'll let you know what I find.

Do you find that this bass is quite middy? I see that the one pup is fairly close to the bridge compared to a P bass, so there is not a lot of thump.

James Judson · #9 05-21-2010, 08:07 PM

One more trick. Build a "jig" just like your bass. Do all your wiring in the jig and when you go to putting the controls back in they will be spaced right for less hassle. Good luck.

Let us know how it goes, it's much easier said than done.

mongo2 · #10 05-21-2010, 08:08 PM

I use thread.

Bassamatic · #11 05-21-2010, 08:37 PM

Thanks Guys - this is now a challenge, and I will have to do it this weekend!

The jig is another great idea - if all the wiring is spaced and tied at the right lengths, there will be less fishing.

62bass · #12 05-22-2010, 01:52 AM

Quote:

Originally Posted by Gio S

Thanks, 62bass. I'll let you know what I find.

Do you find that this bass is quite middy? I see that the one pup is fairly close to the bridge compared to a P bass, so there is not a lot of thump.

Yes, it's strong in the mids for the reason you state and the nature of the pickup. I find the sound if using rounds, to be closer to a Stingray. I use flats on mine. The sound is nice but a bit thin at times. I usually dial in a little bit of bass boost. I've been thinking of routing out for a pickup addition between the stock pickup and the neck. Maybe a Bill Lawrence J45 which is hum cancelling. Lot of extra work though for an uncertain result.

Bassamatic · #13 05-22-2010, 10:16 AM

I see a couple of Bart pickups that are the same size - perhaps one of them can give a little more bottom. I sure like playing this bass, but I would like more of the P sound.

Bassamatic · #14 05-22-2010, 02:10 PM

Well, I am now more confused than ever. I removed the pots and found that they were wired in a standard P-Bass configuration.

I tried an experiment and moved the tone pot connection to the wiper of the Volume pot and now it works properly, EXCEPT at full volume, and then the tone doesn't work at all. Very weird.

The volume pot is B500K and the Tone pot is A500K.

I am wondering if the impedance of this pickup is something really strange and standard pot values don't work for it. Maybe I am missing something.

I have sent the schematic to my super brain engineer to noodle on, and will keep you posted. Meanwhile I will go back and look at it again.

62bass · #15 05-22-2010, 02:40 PM

[quote=Gio S;9162261]Well, I am now more confused than ever. I removed the pots and found that they were wired in a standard P-Bass configuration.

I tried an experiment and moved the tone pot connection to the wiper of the Volume pot and now it works properly, EXCEPT at full volume, and then the tone doesn't work at all. Very weird.

The volume pot is B500K and the Tone pot is A500K.

I am wondering if the impedance of this pickup is something really strange and standard pot values don't work for it. Maybe I am missing something.

Great. At least we now know something was wrong and it can be remedied (sort of) That is weird. Is there any way you can measure the resistance of the pickup?

That was full on volume on the volume pot where it didn't do anything, right? I don't know if I've ever done it but I'll plug mine in today and see if turning down the volume will allow the tone pot to have more effect. I usually, by habit, just crank the volume on any passive bass to full on before I start playing.

It is strange that Ibanez doesn't seem to have noticed this. I don't know if anyone has ever asked them about it or not. Here in Canada it's impossible to communicate to anyone at Ibanez. There is only one distributor who is based in Montreal and doesn't bother answering if you email. In the US there is an actual Ibanez rep who will answer questions apparently.

Anyhow, thanks for what you've done so far and let me know if you find out anything else.

Bassamatic · #16 05-22-2010, 09:31 PM

The DC resistance of the pickup is VERY low - only around 1.4K. I am not sure if this affects anything or not.

Tomorrow, I will try wiring it like a Jazz bass - where the pup hot wire goes to the center of the pot instead of the end and see if that makes any difference.

ALSO - IMO - the pots should be reversed - the Volume should be the A taper and the Tone the B taper. I may just do that as long as I have the iron hot.

Bassamatic · #17 05-23-2010, 12:07 AM

I found many reviews were the user said the same thing - that the tone control "didn't do a whole lot" and that the sound is middy.

I think that we have solved the mystery. I spent an hour talking with my genius engineer about this. He is an instrument and amp specialist by the way.

The very low resistance and impedance of the pickup is the problem. The typical bass pickup is 10x higher. This MAY have been the intention of Ibanez as the low impedance pup will pick up less noise, but they forgot to scale the rest of the circuit to match.

To make it work properly the pots need to be changed to 50K and the cap to around 0.22. However, he said that he would recommend changing the pickup instead, since he has never seen anyone make a good, low-impedance pickup.

Therefore, I am going to start looking for a Bart or something else that fits. I think that the pup is 39x140mm.

I wish that there was an easier fix, but there you have it. This is such a nice looking and playing bass that I feel it will be worth it to make the modifications.

62bass · #18 05-23-2010, 02:37 PM

Quote:

Originally Posted by Gio S

I found many reviews were the user said the same thing - that the tone control "didn't do a whole lot" and that the sound is middy.

I think that we have solved the mystery. I spent an hour talking with my genius engineer about this. He is an instrument and amp specialist by the way.

The very low resistance and impedance of the pickup is the problem. The typical bass pickup is 10x higher. This MAY have been the intention of Ibanez as the low impedance pup will pick up less noise, but they forgot to scale the rest of the circuit to match.

To make it work properly the pots need to be changed to 50K and the cap to around 0.22. However, he said that he would recommend changing the pickup instead, since he has never seen anyone make a good, low-impedance pickup.

Therefore, I am going to start looking for a Bart or something else that fits. I think that the pup is 39x140mm.

I wish that there was an easier fix, but there you have it. This is such a nice looking and playing bass that I feel it will be worth it to make the modifications.

Excellent work! Wow, that really does explain things. Sounds like that pickup would work well with an active buffer circuit.

Well, now you've given me some hope that it can be fixed. I want to save the bass. That impedance thing explains the middy sound too. There should be ton of bass where it is placed.

I'm going to try staying with the pickup and changing the pots. If that doesn't work then I'll look at a pickup swap. I like Duncan over Bartolini myself so I'd look there first. Do you know if there is a Kent Armstrong that would fit? They make a nice pickup too.

Thanks once again Gio! You've made my day. Let me know how you make out with the new pickup. Its'a a good bass and deserves to be played.

oyobass · #19 05-23-2010, 05:13 PM

[quote=62bass;9162333][quote=Gio S;9162261]It is strange that Ibanez doesn't seem to have noticed this. I don't know if anyone has ever asked them about it or not. Here in Canada it's impossible to communicate to anyone at Ibanez. There is only one distributor who is based in Montreal and doesn't bother answering if you email. In the US there is an actual Ibanez rep who will answer questions apparently.
QUOTE]

Several years ago I got no help from Ibanez USA, but the Austrailian distributor was incedibly helpful...

Bassamatic · #20 05-24-2010, 09:25 AM

62bass - I am also going to try the pots - Allparts has 50K audio pots, so I will order a pair today. It should make a HUGE difference. When I had it mis-wired so that there was some low load on the pup, it sounded quite good. By the way, I found that it was not too difficult to get the pots out and back in through the F-Holes. I have a very long nose electronic pliers that helps to guide them back into the holes. I founds that you can stick the pot shafts down into the holes from the top and this will hold them in place while you fool with the wiriing.

I haven't really started the research on the pups, there must be several that will work well here. We can do this while waiting for the 50K pots. Note that the distance from bridge to pup center is still about an inch short of a P standard.

It is amazing that Ibanez produced this bass for several years with this error, and it IS true that trying to get anything out of their service department is futile. My friend owns a music store and when I wanted a new switch for a previous Ibanez bass he told me to just forget it - it was impossible to get any response.

Maybe they thought about adding a preamp/buffer and then dropped the idea without telling the parts department to change the values. Who knows?