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Looking for advice for my LP mods???


 
5/30/1999 8:42 AM
H.Meuse:
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Looking for advice for my LP mods???
I have starterd to install a set of Dimarzio Air Calssic HB's in my EPI LP and am open for sugestions.  
I have 4 push pull pots to install and was going to use two for series/parallel switching and the other two for Phase switching/coil selection with two mini toggles for coil tap.  
I would like to get series/ parallel and phase switching between the two HB's also and am considering a rotary switch in place of the pu selector switch to do this.  
Anybody see another route to get these combinations?  
I would also like to install a plug on the two HB's and pup selector so i can plug the hole wiring assembly in as one harness.  
I have made a small box with holes for the 4 pots and am wiring the thing up on this jig.  
Do you think i could use phone connectors it's gotta be able to accept small guage wires.  
Thanks a lot ifin you got this far!  
Henri M.
 
6/1/1999 3:26 PM
Mark Hammer
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Hey Hank,  
 
How about this. Peavey has a tone circuit which pans between full humbucker and single coil. I saw it in GP years ago (I think Anderton has it in his last collection of guitar DIY projects, the book with the yellow cover). Why not consider having the two tone controls select between traditional tone control functioning and the Peavey circuit? That would get you your coil tap (and more), but still leave a switch for phase-flip and another for series parallel. Just in case I'm blowing hot air here, are these DPDT switches?  
 
Mark in Canada
 
6/1/1999 7:24 PM
H.Meuse:
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Hi Mark how you doin.  
The P/Ps are dpdt that circuit you refer to is the T-60 i belive but it wouldn't give me selection of any combination of the 4 coils.  
I am going over all possiblitys for this circuit it's the first time i've done anything to a LP and it's like surgery trying to work inside the body.  
Mark i have a question for you about an amp circuit.  
I was looking at a schematic for a Delux and want to build a clone and noticed that the circuit dosn't give a value for the choke.  
I have seen this on other schematics also  
i know a choke is different from an inductor but don't you have a value in henrys for the choke same as the inductor?  
Thanks for the reply Mark.  
Henri M.
 
6/2/1999 3:50 PM
Mark Hammer
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I understand your goal, although personally I'm not too fond of the "combination lock" guitar switching systems (this switch in position 2, that one in the up position, and that switch set to position 4). My recommendation for the T-60 circuit was simply because it provides a lot of tonal possibilities, while still letting you play and use the guitar as if it is a 2-pickup axe.  
 
I also find that a lot of the exotic combinations lose their tonal definition and uniqueness once the amp volume goes over a certain point, so I've just lost interest in them. Of the various combinations that might be worth your while (at least to my ears) to try creating would be to identify the magnetic polarity of the coils in the two PU's, and figure out a Push-Pull pot wiring that gets you one coil from each PU to produce a hum-rejecting combination of single-coil sounds from the bridge and neck PU's. I guess the idea is that when the PU selector switch is inthe middle position, you'd yank up the push-pull and cancel one coil from each PU.  
 
Another switch position could be used to produce phase reversal of one entire pickup. Each of these would produce a tone that would be distinct from the other combinations, even with the volume cranked.  
 
I just flipped through my Pittman book, and looked at a bunch of Fenders. None of them list the value of the choke, but all of them list the same part numbers for the choke (125C1A). Seems like it's a pretty standard part that anyone who carries amp repair/building supplies for would carry (not to mention Fender themselves). Given what it does (filter out AC ripple left over after the rectifier has done its work), the specs on it are probably pretty generic. As long as it can handle the voltage/current, I can't imagine the specs making an audible difference, unless you are dead set on eliminating all hum down to zero. It's worth noting that plenty of Fender and other amps lack a choke on the power supply, and do fine without it, relying more on the filter capacitors to do the cleanup work on the power line.  
 
I may be talking through my hat here, but it seems to me that some might see upping the capacitance, instead of using a choke, as the preferred approach, since it could increase headroom. Bear in mind that while chokes don't store current, capacitors DO. That is, they both serve to help turn the AC into something more like DC, but caps bring a bonus.  
 
How's that aircraft carrier you drive?
 
6/2/1999 10:06 PM
H.Meuse:
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Mark check the Ya butt post as i entered my reply as a new post.  
i wondered why it required a subject whatt a heading.  
H.M.
 
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