doubleneck acoustic electronics??

Thread Starter

hiawatha444

Joined May 17, 2008
4
Hello I am a luthier, www.myspace.com/greatestguitars..


My question is , I am for the first time using an LR. Baggs Imix system in a doubleneck acoustic.. Ive done this before the problem I am havin now is I am running 4 pickups into one preamp?? Each guitar on this double neck has 2 pickups?? I have 2 3 way switches for each set of pickups but have major ground problems.. The 3 way switches are the same from an Ovation doubleneck but they us different electronics and only 1 pickup per guitar.... My head hurts and Im trying to figure out how to explain..


Thank you any questions I will answer and help will be appreciated. As soon as I figure this out thats 5000$ in my pocket.. Its made for someone..

Kevin Clark
 

Audioguru

Joined Dec 20, 2007
11,248
I also looked to see what the heck is a Luthier. A repairman for stringed instruments.

I never found a circuit with 4 pickups switched into one preamp.

There will be lots of hum unless shielded audio cable is used from each pickup to the switch and to the preamp.
 

Wendy

Joined Mar 24, 2008
23,415
Is the switch on the guitar? Don't need exact plans, but it would help if we had an appoximate layout. You have to realize while we know a lot about electronics few of us know anything about guitars and how they are arranged.

I wonder if an electronics switch toggled by the mechanical ones could help?
 

thingmaker3

Joined May 16, 2005
5,083
A repairman for stringed instruments.
Or a highly skilled craftsman who creates quality instruments from scratch.

Here is the Imix installation manual: http://www.lrbaggs.com/manuals/imix_manual.pdf

The first five pages deal with luthier stuff and are over my head. Page six is where the comprehensible stuff starts.

From a quick Google search, it looks like the double-neck guitars have standard jacks and some kind of switched mixer to go from one pickup (or pickup group) to the other.

If the Imix pickup pair uses the same scheme, it might be necessary to use a third "3 way switch" on a doubleneck with with two Imixs.

Note: "3 way switch" seems to have a different meaning in this context than the lighting switches I'm used to. I think it is a switched mixer of some kind.
 

Wendy

Joined Mar 24, 2008
23,415
Where are the switches located? My thought was to use some form of electronic switch that are controlled by mechanical switches. This way the electronic switches could be well shielded and in line with the transmission lines. Just a suggestion, try making a simple drawing showing where the pickups are, where you want them, and where the mechanical switches are.

I can't promise anything, but I believe we can help you, within the limits of our knowledge. For the rest of the guys, my current thought is some form of diode switch. This will require a printed circuit board, but a pretty simple one. There are other ways of doing this of course, but that is my take.
 

Wendy

Joined Mar 24, 2008
23,415
Are the switches carring the audio signal?

Is the problem hum, or where to put the pickups, or what?
 
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Thread Starter

hiawatha444

Joined May 17, 2008
4
The problem is 60 cycle HUM .. The weird thing is if I plug just the 3 way switches without any pickups there is major humm?? Im going to try different switches because maybe there is a crossover somewhere in these.. The pickups and the preamp work fine because without the 3 ways and just 2 pickups plugged to the preamp no humm...
 

thingmaker3

Joined May 16, 2005
5,083
Based on the installation manual, and the comments on various sites Googled, I think they do. Each switch seems to select "iBeam pickup," or "element pickup," or both. There is one of each type of pickup in both necks.

Hiawatha, was this kit marketed as one for a doubleneck? Or did you acquire two kits?
 

SgtWookie

Joined Jul 17, 2007
22,230
The problem is 60 cycle HUM .. The weird thing is if I plug just the 3 way switches without any pickups there is major humm?? Im going to try different switches because maybe there is a crossover somewhere in these.. The pickups and the preamp work fine because without the 3 ways and just 2 pickups plugged to the preamp no humm...
Anyone who creates or repairs musical instruments is automatically a friend of mine. Luthiers fall neatly into that category.

You must ensure that your guitar has only ONE ground path. If there is more than one ground path, you will have horrific 60 cycle noise, and you will not be able to rid yourself of it until there is only one path to ground. This is basic, very stark and heinous. But it is truthful. You will not rid yourself of the 60 cycle hum until there is only ONE path to ground.

You currently have multiple paths to ground. You must eliminate all but one. Until you do that, you will not be able to deliver the instrument, because as a Luthier, you cannot knowingly deliver a defective instrument.

What you have in front of you is a process of elimination; elimination of multiple ground paths. We'll help you (well, I will!) in that process.
 

thingmaker3

Joined May 16, 2005
5,083
I'm getting additional confusion while searching. It seems some of the "three way switches" are double pole quintuple throw.:confused: Whether they are "five-way" or "three-way" depends on wiring.

Hiawatha, can we get a photo of the underside of the circuit board the switch is mounted on?
 

Thread Starter

hiawatha444

Joined May 17, 2008
4
Finally found the main problem!!! Shielding the switches didnt work fully. I had to shield where the switches plug in to the preamp. God that wasnt fun. The 2 plugs acted like a microphone . It is now the first time anyone has done that and Lr baggs is so excited. I want to thank them you guys and Doug Blair of the band WASP.. Hes an electronics genius as well.

This site is in my favorites because i think i will learn a lot here...

Have fun Kevin
 
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