Conference napalm::guitar

My guitar is home made with an Aria neck, and was wired by my friend back
in my high school days.  It has Dimarzio Super II pickups (humbucking, 
I think).  The volume and tone controls behave very nonlinear audiowise, and
thus I would like to rewire things.  The schematic follows:


       +--------+
       |        +-------------+------------------------+
       | Pickup |             |                        |
       |   1    |             /                        |
       |        +---+      R1 \<-------+               |
       +--------+   |         /        | C1            |
                    |         |       ---              |
                    |         +       ---              | R2
                    |                  |               V
               +----+------------------+------------/\/\/\/\----+
               |    |                                           o /
               |    |                                            /  
           GND +    |                                      DPST o-------> out
                    |               
                    |                                           o     +->
                    +------------------+------------/\/\/\/\----+     |
                    |                  | C2            ^              |
                    |         +       ---              | R4           |
                    |         |       ---              |              + GND
       +--------+   |         /        |               |
       |        +---+      R3 \<-------+               |
       | Pickup |             /                        |
       |   2    |             |                        |
       |        +-------------+------------------------+
       +--------+

Does anyone have any ideas on determining the correct values for the R's
and C's?  I don't have any technical specs on the pickups.  Should both
the volume pots (R2 and R4) and the tone control pots (R1 and R3) be
audio taper, or just the volume pots?

Does anybody know of any good books on the subject and where to pick them
up?

Todd.

	Volume pot's for humbuckers are 500k and tone controls are either
50k or 500k ohms. The center terminal is the output of a pot,the filtering
cap's are typically .02 microfarads ceramic radial lead. The sheild from 
the pickups goes to ground and the center conducter is what carries the 
signal. Some Fender's with single coil pickup's had 250k volume pot's,I'm
not sure what they are today as I heard that this was changed later. Whether
the pot's are audio(logarithmic) or linear I can't remember maybe some
one else would know.


						Rick

    If you have problems with the treble rolling off as you decrease
    the volume, try substituting 1M pots for the volume controls, this
    helps and doesn't seem to have any adverse effects on the guitar.
    You can also experiment with putting a bypass cap around the volume
    control so that the highs do not get attenuated. I tried this on
    my tele and was amazed at how hot the thing sounded.....unfortunatley
    there were some adverse effects using a cap of the size that seemed
    to boost the mids, the volume control really didn't work anymore,
    it became a mid roll off....experimentation is the key, start with
    .005 uf cap....I ended up taking it out as the pickups are so poor
    that someday (that mythical someday) I'm gonna have semour duncan rewind
    them.                                                      
    
    dave

    
    I would like to hear from anyone that has replaced STRAT pickups
    with the EMG system. What was involved, how long do the batterys
    last, what type of sound etc etc... (and cost )....
    
    			Joe.

    
    Since someone mentioned re-wrapping their pickups, I was wondering
    if someone would mind giving a little discourse on that topic. 
    I have a '60s Les Paul deluxe with the original little deluxe
    humbuckers.  One of them isn't working any more and a friend told
    me I needed it re-wrapped.  I am interested in recommendations.
    Is this something you should try to do yourself?  If not, know
    a good source??  About how much would it cost? Etc...
    
    /Dino

    I don't know about your set-up, but the pots on my
    Ibanez AS200 and 62 Gibson SG are both definitely
    linear.  I can't think of any reason an "audio"
    taper pot would not work but, I also can't think 
    of any reason to use one.
    
    Doug D.....
    
               

	re .0:

	I've got a book called "Guitar Electronics".  Don't know the
	author, publisher, etc. off the top of my head.  If you want
	I can get that info and post it here.  I got it via mail 
	several years ago.  It has lots of good info on the hows and
	whys of guitar electronics.  Even includes schematics of some
	of the more popular models (strats, teles, LPs, etc.)

	-gary

	I've tried Emg pickup's on a Guild Bluesbird and found they had
a nice even sound. I currently am looking at the DiMarzio shock wave 
system for the Strat's. Emg has an active system which emphasizes the
middle tone's which Larry Carlton uses on his Strat shaped guitar made
by Valley Art's of LA. Steve Lutkather(sp) also use's an Emg setup.
	I'll let you know what I think of the Shock wave system if I
get a chance to try them. Why are you going in this direction?


							Rick

In general, if the potentiometer is controlling volume,
you should use an audio (logarithmic) taper potentiometer.
Your ears are sensitive to volume in a logarithmic manner.
The deciBel dB scale is logarithmic.

Did you ever see the MCI (or one of those new guys) commercial
where over their new fiber optic phone line, they explode
a perfectly innocent glass with a signal amplified to 140 dB?
Well, a rock concert is in the 90 dBs.  Which is loud enough
to cause permanent hearing damage.  It also causes
spontaneous unconsiousness and vile behaviour in teenage
males for reasons scientists do not yet fully understand.
And 140 dB is *not* about 1.5 times as loud as 90 dB.
Every 3 dB is about twice as loud. Or something like that.
But your ears listen logarithmically and you sense a linear
change in volume.  At 140 dB, it's not suprising that they
shattered the glass.  They could have shattered a couch
or even a small housepet.  And then I would have been
impressed ;-).  But anyway . . .

If the potentiometer is controlling frequency, you should
use a linear taper potentiometer.

If you use linear taper pots to control your volume -
your ears sense a non-linear change in volume.
The Radio Shack pots have an 'A' stamped on them for
audio taper, and a 'B' for linear taper (obviously).
But don't buy your pots at Radio Shack - they are not
good enough for your guitar.

				3 dB off center,

					Tim

    re: Rewinding pickups
    
    First this is not something *I* woudl want to do....to get a tight
    wind you need equipment or infinite patience...and 28-32 gage wire
    breaks sooooo easy....
    
    Semour Duncan will rewind you pickups for you, last time I checked
    it cost $35 per pickup and turnaround time was 2 months. Since I
    am extremely pleased with everything I ever bought from duncan,
    eventually I'll send him my tele humbuckers for a rewind.
    
    Are you sure that the pickup needs rewinding? It'd be a shame to
    spend the time and money to find out that a broken wire in the guitar
    or bad switch is the problem. Case in point: In my old band the
    other guitar player had a very old stereo gibson (like a 335..347
    perhaps??) anyway it had a true classic sound, he felt that one
    of the pickups had lost it's bite and was in the process of dying,
    so he replaced it with a duncan classic something or other mumble
    mumble...anyway he was pleased. I bought the old pickup for $5.
    There was nothing wrong with it....it now graces our old bass player's
    homemade 6 string...and screams like nobody's business...
    
    dave 

RE: Dave
Thanks for the info on the 1 Meggers, I'll give 'em a shot.

RE: .7
I am interested in the information on that book.  I'd be grateful if
you could post the details.

RE: .9
Thanks for the info on the audio vs. linear taper.  You mention not to
buy pots at RS (for obvious reasons).  Where is a good place to get
top notch pots?


Now, I have an additional question regarding grounding.  My guitar seems 
to hum unless I put my hand across the strings, which leads me to believe 
that I am grounding out the hum.  Are the strings supposed to be grounded 
by grounding the nut or the bridge to the electronics ground?

Todd.

    	Most guitar's have the bridge grounded to the guitar electronics,
    with Gibson's there is a wire which comes from the stop tailpiece
    where the strings are attached. With Strats there is a wiregrounded
    to the tremelo spring unit behind a plastic plate..
    
    
    							Rick
    

                                               
    Re: grounding
    
    Most guitars ground the bridge to the shield of the output jack
    as it is quick, dirty, usually comes pretty close to working right
    and also is useful for electrocuting guitarists!!!!
                          
    I have heard some repairmen expound on placing a small cap between
    the bridge and the output jack, to give AC a path to ground but
    not DC supposedly lessening shock hazards.  Sounds good, but most
    shocks are via AC which should pass right through the cap!
                                                       
    Grounding and shielding is a sore point with me.  I have two really
    cheap basses (a Peavey and a Danelectro) that are ultra-quiet and
    two very expensive ones (a Rich and a Fender Elite) which tend to
    buzz like crazy.  I did put the Rich into the shop and had the
    repairman add extra shielding, resolder some of the ground wires,
    etc. to try to minimize the ground loops, etc. and it *did* improve.
    
    Good shielding and grounding must be part of the *pickup* design
    itself because this is where the noise is usually induced.  Humbucking
    pickups of course can help considerably but the Danelectro pickups
    are single-coil and very, very quiet.
    
    A lot of this is black magic but rest assured that a lot of very
    expensive guitars do hum.  One way to get around it is use battery
    powered amps....no AC, no hum!!!   More seriously, a preamp can
    often help reduce hum because it buffers the pickup from the amplifier.
    

    Re: 11
    Years ago I installed Bournes pots in my ES335 (long gone :'( ).
    They were expensive (around $9.00) but were very smooth. I recall
    wiring them was tricky because the tabs are very small. They don't 
    look like your average pot, as they're rectangular, and hermetically 
    sealed. I bought them at an electronics store, you might try U-DO-IT
    or someplace like that. 

    Dan

    
    Active Pickups (EMG)
    
    	I am considering EMG as I like the clean bell like tone, I also
    do do not appreciate the hum from the stock single coil pickups.
    
    	I also have an eight year old Les Paul pro with the single coil
    white P90 pickups, I would like to replace them ,does anyone have
    experience with a P90 replacement ?
    
              Joe.

    re: .11 and grounding
    
    My strat is grounded in the conventional fashion with a wire to
    the tremelo unit. It still hums a bit unless I touch the strings.
    I wrote Semour Duncan and asked if they had any ideas (since ALL
    my electrics do this to some degree....) they said check the ground.
    
    Sigh.....I was told once, way back and I forget where, that the
    capacitance of your body somehow kills the hum, I've never spent
    a lot of time thinking about it.
    
    re: the les paul pro
    
    Semour Duncan makes a replacement for the old gibson "soapbar" pickups
    the SP90-1N (neck) and the SP90-1B (bridge) I dunno if that's what
    you're looking for. 
    
    dave

    Re. Guitar Wiring book. I have this book at home. I can't
    think of the author's name off the top of my head, but I know
    for sure you can order it from Bold Strummer. I get the Bold
    Strummer cataloque ever few month's in the mail. They must have
    gotten my name from Guitar Player magazine or Frets.
                                          
    I will be on vacation next week, but when I come back if you still
    need some info on the book, I will get it for you.
                       
    							Mark Jacques
    

	re: .11  I'll post the info on the book as soon as I get back
	         from vacation next week also.  I believe it is called
		 "Guitar Electroics" by David Brosnac, but I'll have to
		 look up the publisher.

	-gary

    re. .18 I love your nodename! Where is this system located.
    

    re .19:

    > re. .18 I love your nodename! Where is this system located.

	It a MicroVAX 2 (with 9 MB memory) in my office here in 
	Burlington, Vt.  Personal Vaxes are great!

	-gary
    

See note 8.* for a few more details about pickup wiring.

	I had an oppurtunity to try before I buy a Dimarzio Shockwave setup 
for a Strat style guitar. Unfortunately it didn't come with instructions
for hookup so a few phone calls to Dimarzio's technical assistance line
provided me with the necessary info to hook it up. I also had an oppurtunity
to talk to the designer of the pickup's and the system. The obvious question
I had was is this just a HS1,2,3 with a preamp. The answer was no that the
pickups were specifically designed and built for the active setup. His own
personal opinion on pickups of this nature was that the HS2's had the closest
characteristics to the actual strat sound. His other comment was that the more
gain you get the greater the chances of losing some of that sound.
	I found the gain increase in the shock wave system to be adequate to
compete with my Gibson which has old Les Paul pickup's. The single coil hum
which is characteristic  was gone as the pickup is a stacked humbucker. The
active preamp fits into the cavity where the guitar output jack was even though
the screw holes didn't line up. There is a switch which will bypass the preamp
(in case of battery failure)and the output jack lock's the cable in place.
	Tone... I found the pickup's to have a little more treble and really
felt that with the 3 main postions were different from the standard sound of
course this is very subjective. The 2 out of phase positons sounded very much
like they were suppose to with more volume(I prefered these tones). There was
absolutely no distortion with these pickups just volume and tone. 
	In Summary I returned the active system and will try the HS series of 
pickups. I liked the gain increase,but typically I like having more lo and mid's
in the 3 positions with the out of phase sounds the same in the other 2 posit-
ions.

	The book I have is titled "Guitar Electronics: A Workbook"
	by Donald Brosnac.  It is published by 

			d.B. Music Company
			P.O. Box 953
			Ojai, California 923023

	It says on the front page that it was originally published by
	Bold Strummer LTD.  (same book as -.?)

	I saw it advertised in Guitar Player mag a few years ago and
	ordered it directly from db.  

	-gary

Thanks for posting the info...

Todd.

    I have a question about combining the output of two pickups. I am
    using a stereo guitar (ES-345), but often want to run both channels
    into a single input. One way I achieve this is using a chord which
    has a stereo jack on one end and a mono jack on the other end. I
    have simply wired the hot lead on the mono jack to both hot leads
    on the stereo jack. When I use this, however, there is a cancelling
    effect between the two pickups. That is, if I turn the volume all
    the way down on one pickup I get no output fromt the other pickup
    at all, even if it is the only one selected with the switch on the
    guitar. In order to get full volume from either pickup I have to
    keep the other one up around half volume.
    
    Is there some easy way to fix this? I recall in the past having
    cancelling effects similar to this when mixing line level signals,
    and having fixed it by putting a 10K resistor across the two hot
    signals. Do I need to do something like this, and if so, what resistive
    value would be appropriate for my humbucking pickups (Gibson
    originals)?
    
    - Ram
    

    	I had an Es 355 Stereo for years and what I found was a passive
    mixer(2 input) was my best bet. It was made by Switchcraft and had
    two wheel type knobs to mix the pickups. I may still have it kicking
    around. I remember it costing $15,but this may not solve your problem.
    
    							Rick
    

re: < Note 332.25 by ERLANG::SUDAMA "Living is easy with eyes closed..." >

>    I have simply wired the hot lead on the mono jack to both hot leads
>    on the stereo jack. When I use this, however, there is a cancelling
>    effect between the two pickups. That is, if I turn the volume all
>    the way down on one pickup I get no output fromt the other pickup
>    at all, even if it is the only one selected with the switch on the
>    guitar. In order to get full volume from either pickup I have to
>    keep the other one up around half volume.

The volume control on the guitar is very probably a voltage divider;
the full resistance is wired in parallel to the pickup, and the potentiometer
wiper arm feeds what you call the hot wire lead.
If you wire the two wiper arm outputs together, each pot serves to provide 
a path to ground for the signal from each pot.  Resistive isolation will
provide some benefit, but a fully passive system will always leave some
cross coupling.  Connect each output from the guitar to a 10K to 33K ohm
resistor, and wire the other ends of the resistors together to the mono
output.  I can't vouch for how the sound will  change, but guitars and
amps tend to be fairly high impedance devices, so a few K ohms shouldn't
affect the sound too much.

         |--------|              |---------|
        O||       \              \        O||
        O||       /              /        O||
        O||       \<-----+       \        O||
        O||       /      |A      /        O||
        O||       \      |       \        O||
        O||       /      +---B-->/        O||
         |        |      |       |        O||
         |--------|      |       |---------|
      pickup 1   vol 1   |  vol 2        pickup 2
                         |
                         |
                         volume 2 here grounds out pickup 1's signal

         add resistors at points A and B to provide some isolation

- tom]

    Boy, have I got a dumb question for you techno_weenies.  Here's the
    problem, maybe you can gimme a fix:
    
    Marshall 4x12 loaded with 16ohm speakers ... only 3 are working.  Is
    there some magical dew-dah I can wire in that will represent a 16ohm
    load so I can wire the cab up to yield 4 ohms ?  I've got a spare 8 ohm
    speaker, but we don't wanna drop down below 4 ohms do we ?
    
    Your suggestions, along with real SIMPLE drawings will be appreciated.
    
    
    Jerry

    Yo Scary-mon,
    
    I'm not a Marshall owner, so this free advice is worth every cent.  
    
    I'd guess your 4X12 is wired to present 4ohms to the amplifer, meaning
    all four 16ohms loads are wired in parallel.  You could put in a 16ohm
    resistor that had pretty massive power handling capabilty, like 50 or
    100 watts, put the problem is a resistor presents only a resistive load
    to the amp.  Impedance is actually made up of two components:
    resistance and reactance.  The reactance varies with the frequency,
    which is why a speaker impedance curve shows variation when plotted
    against frequency.  Some amplifiers hate seeing purely resistive loads,
    but I'm overstepping my knowledge boundary now.
    
    My recommendation is to buy a new speaker.
    
    I think you could get away with installing a hunky resistor, but the
    tone of the system will change slightly.  I've used pads ( as resistive
    networks are sometimes called ) to lower the volume of an individual
    monitor speaker but the tone definitely changed as I rotated the
    volume control and in a different way than when I lowered the amp
    volume.

    I believe (but I'm not sure really) that the speakers are 4 ohms each,
    and they are all wired in series to add up to a 16 ohm load at the
    jack in a Marshall 4X12. The Marshall heads have a two position switch
    which selects either 8 ohms (two 4X12's connected to the two parallel
    speaker outputs = 8 ohms) or 16 ohms (one 4X12 cabinet). 
    
    If I'm correct, you would need a 4 ohm load to replace a missing
    sspeaker,.. but really what you need is a speaker as was said before.
    
    If you don't understand impedances and how they work when in series and
    or in parallel,. or if you're not sure about the wiring/imp[edance
    of the cabinet before you mucked with it,.. or if you don't have the
    meters and the know how to use them and do this right,.. save yourself
    a lot of guessing and wonderin and potential disaster (blown head!)
    and get a new speaker and either put it in yourself,.. or have someone
    do it for you.
    
    							/Bill
    

    Nope ... 16ohm speakers for sure, wired in parallel for 4 ohm load.
    
    I'll just have my other speaker repaired and have the cab like it ought
    to be.
    
    
    Jerry

    Marshall wires their cabs series/parallel and uses either 16 or 8 ohm
    speakers, giving a total cab impedence equal to that of any one of the
    4 speakers.  
    
    Greg

    What about those funkty 15ohm Celestions that have been known to pop
    up in various circles?!

    Well, to be honest, these speakers *are* 15ohm, sez so right on the
    magnet cover.  Am I special ?

RE: Scary and 15 Ohm.

Your special Scary-mon, but if any celestions  come straight out
of England, then they say 15ohm on the back.  My Marshall has 15ohmers
in it.
jc

    Are UK ohms and USA ohms the same?  If not, what is the conversion
    factor?
    \Gary

        Can't tell  you  that  Gary  - you'd try to repeal Ohms Law and
        then where would we be?
        
        Andy
        

    British ohms are metric.  To convert to US, you multiply by 9/5 and
    add 32...
    
    ;-)

    They can repeal Ohm's Law all they want, but HANDS OFF COLE'S LAW!!!
    ... then we'd only be left with potato salad.
    
    Also, does anyone have Avogadro's number?  I keep calling information
    and they say he's not listed.
    \Gary

    
    It's listed under "fruits & vegetables"...
    
    
    guy

    I believe that the difference is due to differences in the way
    impedence (not resistance) is/was measured between our two countries. 
    Ohm's Law still applies...
    
    Greg

    Well, at least Planck's constant.
    
    Dave

Ref the last few replies.........


I agree, and (not being a Marshall owner) you do need to check that what value
the  individual speaker impedances are before replacing with a resistor or a 
new speaker.

The point of this reply is that, IMO, the fact that one of the speakers is 
replaced by a pure resistance does not mean too much to the amplifier due
to the fact that the amp "sees" 3 speakers plus a resistor.  So it will see
a resitive and (slightly) reduced inductance load. In pratice this means you 
will not hear a difference and the amp will not be harmed. 

By the way (and this is REALLY sneaky), I once replaced a blown speaker by
purchasing (for a fraction of the price of a speaker), a voice coil of the
same make. This ensured I got the same resistance/inductance as the real thing.

Instead of paying out 150 dollars for a speaker, it cost me about 18 dollars. 

I was hard up in those days though..........!!!!

Dave

    
    
    
    Hey, double E types: is the voice coil enough by itself, or do you need
    the magnet to achieve the inductance?
    
    

    I believe that the inductance of a coil will change as you start 
    shoving metal and/or magnets up its core.

	Sort of a wiring question.

        My friend Lucy has 2 Shure microphones, model 545S which she bought in
        the 70's sometime. Recently the cables started to wear out and she 
        bought 2 new cables from a music store. Neither worked so she returned 
        them. The guy at the counter reworked both of the old cables and then
        they really didn't work. So to get right to the source I ordered 2 new
        cables from Shure. This is how the instructions read:

        "MODEL C56 REPLACEMENT CABLE AND PLUG ASSEMBLY

                The Shure Model C56 Cable and Plug Assembly is a 4.6m (15ft)
        three conductor shielded cable with an Amphenol type MC4M connector.
        The C56 is a direct replacement for the cable supplied with the 
        Shure Model 545,545S,565, and 565S Microphones.

                Either high- or low-impedance operation of these microphones
        is selected by the leads chosen for connection at the equipment end
        of the cable. For high impedance, the RED lead is the "hot" conductor;
        the shield is connected to the amplifier or chassis ground. For 
        balanced-line low impedance, the BLACK and WHITE leads are the "hot"
        conductors; the shield is connected to the amplifier or chassis
        ground. Any leads not used for a particular connection should be 
        insulated."

        They supply all the hardware but have left it to me to wire the 
        1/4 inch plug. How do I decide which wiring option to choose ?
        The old ones seem to be wired for high impedance but I'm not sure
        if the guy at the music store did that. She uses a small Peavey 
    	PA system.

        Input ?

        Thanks.

                Ray.

    
    

Ray,

Do the 545S's take an XLR plug, sometimes called a Cannon connector?  XLR's
usually have three female receptacles spaced at 120degrees around a circle.
I'm not familiar with the Amphenol p/n.

Did Shure supply you with a conventional (tip and sleeve) 1/4in plug?.  To use
the low impedance feature of the microphone, you need a special 1/4in plug that
has a tip, a sleeve, and a ring.  You'll see it on the plug supplied with the
cable.  Otherwise, you'll need to use the high impedance configuration. 
Connect the red to the tip, shield to the sleeve.

If you have a stereo phone plug (i.e tip/ring/sleeve) *AND* the Peavey board
is wired to take low impedance microphones with that kind of plug (doubtful,
IMHO), then wire black to tip, white to ring, shield to sleeve.

If the Peavey has XLR connectors for mic inputs in addition to the 1/4in 
plugs, then my suggestion would to make the microphone cable as:

	MC4M ======================================= A3M ( XLR connector
                                                           style designator:
						           A :== cable type 
							   3 :== 3 conductor
							   M :== male )

and put black to pin 3, white to pin 2, shield to pin 1 on the A3M.

Hope this helps. If possible, you should use the low impedance feature because
it offers better noise rejection and there's practically no limit on cable 
length.

    I've wired my Strats up so that the lower tone pot works with the bridge
    pickup rather than the middle pickup. This makes the bridge PU much more
    usable in my opinion. You can take the screechiness away when you're
    pushing the amp into clipping. I have no trouble getting a "Hideaway"
    type tone from it. I think just having the control on the pickup, even
    when it's left at "10", smooths the pickup out some.

    This scheme leaves the middle PU with no tone control when used by
    itself. So I've decided to wire the upper tone pot like a master tone
    control like on a Tele. This way I can leave the neck and middle PUs
    open and back off just the bridge, or roll everything back. The only
    thing I need to add is a second .1 mf cap. If anyone's interested, I'll
    put the diagram in here.

    I also use a 1000pf cap across the vol pot to maintain the highend when
    using a setting less than "10". These are simple changes but make a big
    difference in my opinion.

    One difference from what I described in -1:

    I put the Tone1 control on the neck and mid pickups only and not on the
    master signal path as I had previously mentioned. To wire wire Tone1 as
    a master tone control, simply connect it to the common node on the
    switch, i.e. the input to the volume control, and use a separate
    0.1mf cap to ground.


   pickups    |  5-position  |  controls           | output
              |  switch      |                     |
        
   |(--------------o
   |(_ neck                               1000pf
      |       +----o<--+----------------+---||---+
     ///      |        |                |        |
   |(---------+  +-o   |                |        |
   |(_ middle    |     |jumper          \        |
      |          |     |across          /<-------+----v |
     ///         |     |switch          \ Volume        | Jack
   |(------------+     |commons         / 250K      +---+
   |(_ bridge          |                |           |
      |                |   o---+----+   ///         ///
     ///               |       |*   |
                       +-->o---+    \ Tone#1
               other half       250K/
               5-position  o--+     \<--+
               switch         |     /   |
                              \         |
                          250K/         |
                       Tone#2 \<--------+----||--+
                              /            0.1mf |
                                                ///

    * jumper across switch terminals

    Below is the stock tone control wiring:
    
                       |   o--------+
                       |            |
                       +-->o--+     \Tone#1
               other half     | 250K/<----+
               5-position  o  |     \     |
               switch         |     /     |
                              \           |
                          250K/           |
                       Tone#2 \<----------+--||--+
                              /            0.1mf |
                                                ///

NOTES:
Although 0.1mf caps are traditionally used in the Stratocaster tone
circuit, other values that have been used are 0.022mf (which I believe
is used in the American Standard) and 0.05mf (Telecaster).

Some guitars use larger value (500K) potentiometers.

If you feel that the volume control isn't as smooth as it sould be,
a 150K to 200K 1/4 watt resister can be placed across the 1000pf cap.
I don't think it's worth the bother.

        I have an 1983 American Start that has one tone and one volume the
    input jack plugs in where the volume would normally go.

    The tone knob does almost nothing, it is either on or off.  I would
    like to make it more sensitive all the way from 1 to 10 what do you
    guys recommend?
    
    regards,
    One Tone Patla
    

    Yo One-tone,

    First I'd make sure they didn't use a 1Meg pot for tone. 250K to 500K
    pots are normally used along with a 0.1 or 0.05 uF cap. The classic
    strat tone control is a 250K pot and 0.1uF cap.

    --Ron

   Here's an interesting problem that one of you electronics types might be able
to easily answer ...

   I have a Marshall head (30th Anniversary) with a two speaker output jacks,
which are wired in parallel.  Speaker jack output impedence can be set to either
8 or 16 ohms.

   My problem is that I'd like to able to use one or, on occassion, two 8-ohm
speaker cabs.  However, two 8-ohm speaker cabs, in parallel, yield a 4-ohm load.
Although I'm told by the Marshall hotline support people that I can have the
transformer tap on my amp changed to support 4- and 8-ohm loads, I don't want to
modify the amp.

   There must be some kind of simple box that would allow me to plug two 8-ohm
cabs into it, and come out the other side of the box with a 16-ohm load, right?
Seems that the wiring would just put the two 8-ohm loads in series ... or am I
missing something here?

 +-----+
 | O O = -- 8 ohms\  +------+
 +-----+           \->=     |                 +-----------+
Speakers             |      = --> 16 ohms --> = Amplifier |
 +-----+           /->=     |                 +-----------+
 | O O = -- 8 ohms/  +------+
 +-----+

            Thanks, Andr�

    Re: .52 
    
    Yes, what you want is to wire the two cabs in *series* rather than
    parallel.  Here's a schematic of what you need to hook up:
    
    
    				AMP
    
    		       (+)	       (-)
    			|		|
    			|		|
    			|		|
    			|		|
                       (+) (-)-----(+) (-)
        
                       CAB #1       CAB #2
    
    							Brian

    Andr,
    
    Two 8 ohm spkr cabs in series combination:

    Cab-A   (+) --------+
    8 ohm   (-) --+     |
                  |     +-- (+)  amplifier's
                  |     +-- (-)  16 ohm spkr out
    Cab-B   (+) --+     |
    8 ohm   (-) --------+
    

    --Ron

     The Marshall output impedance select can be wired for 8 & 16 ohm (normal)
     or 4 & 8 ohm according Note #4 on the schematic. It would take nothing
     more than a soldering iron once the head is out of the cab, and can be
     reversed with no ill effect.

     Neal

    Does anyone have any experience with humbuckers in Telecasters? 
    I just installed a very old PAF in the neck position of a standard
    Tele, (the usual tele with two single coils,) and I'm wondering if I'm
    going to run into problems when I plug it in. I realize I could just
    fire it up and see, but I won't have access to any of my amps for a few
    days. 
    
    The guitar has 250k tone & volume pots. 
    
    
    Oh well, I'll let you know what happens. If the outputs are radically
    different, I'll ask for advice. In the meantime, I'm wondering if
    anyone has done this before, (besides Jeff Beck?)
    
    

    The only thing I know of is that the vol pot may need to be 500K. I put
    a Gibson Hummbucker in my strat once (like 1971) and its output was
    miserably low compared to the Strat single-coils. I aborted the whole
    project because of that, but in retrospect I wonder if it was because of
    the 250K pots.

    I'd like to know how this turns out. My Tele is nicely routed for one of
    those and I have a couple mid-sixties 'buckers lying around that I'm
    tempted to try. If I wasn't so crazy about the sound of the neck pickup
    that's in it, I'd do it in a heartbeat. But I do like the neck pickup a
    lot so I'm not anxious to undertake the effort.

    --Ron

   You may also have to have the height of the humbucker lower, and the 

single coil pickup higher to get a balance in volume. If the output of

the humbucker is too high (compaired to the single coil), you will not

get a good mix between the two, ie; one drowns out the other.



/J