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Post by cynical1 on Dec 4, 2008 19:35:18 GMT -5
OK, it's been pretty quiet here lately, so I thought I'd throw this one out.
Why is it that a Strat has 3 pickups, the HHS and HSS guitars all have three pickups, but there's never three volume controls?
Just curious...
Happy Trails
Cynical One
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Post by newey on Dec 4, 2008 19:55:15 GMT -5
If there isn't such a thing, it's only because none of us has gotten around to building one yet!  I suspect a thorough Googling would disclose such a guitar, albeit not a "factory" model. A Strat with 3 concentric pots, V & T for each pickup, might prove very useful. I also think (with zero data to back this up . . ) that, back in Vintage Days of Yore, control over tone was more important than control over volume due to the limitations of the amplifiers then in use. And, let's not forget that, where Strats are concerned, Leo was not a guitarist. So the idea that some rational thought went into the decision to have 1 V and 2 Ts may be an ill-founded assumption in the first place. |
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Post by ChrisK on Dec 4, 2008 20:14:55 GMT -5
There have been three pickup guitars with three volume pots. Some early Epiphone and Gibson's come to mind. There have been three volume SGs and LPs.
I have seen home-built ones with this.
Yes, this is why the Strat has two tone controls (neck, middle) and not three (one on the bridge). The high frequency response of the early amps was dismal, and one needed all the brightness one could muster from the bridge pickup.
Not really. With the info above, and the volume control placed real near the bridge pickup (pinky swells, anyone) based on voice of the customer (well, some of the customers back then), the two tones gave one fixed (bridge) and two adjustable (neck, middle) tone settings for that there 3-way switch that was used (the 5-way didn't "notch" its way onto the scene until the 60's).
This is exactly why the tone cap is shared (ain't never was more than one pickup on at a time).
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Post by andy on Dec 4, 2008 20:38:22 GMT -5
I knew I'd find this somewhere!  Now discontinued, it seems, but I'm pretty sure those are all volumes, even the one on the lower horn as a master. I've seen photos of T-bone Walker and Chuck Berry using something similar, but I couldn't find them tonight. |
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Post by cynical1 on Dec 4, 2008 22:23:27 GMT -5
I suspect a thorough Googling would disclose such a guitar Honestly, I've been Googling til my fingers bled, and only found a scant few designs. I've got two projects I'm toying with and was looking for some inspiration...but it seems to most popular versions of a "3 volume" revolve around either an SG or a 3 pickup Les Paul, and I'm not using all humbuckers... My projects are a HSS guitar and a Peavey Bass with existing "jazz type" single coils that I was thinking of dropping a P-bass pickup between. I found one design here, but it had everything from soup to nuts on it. I'm more of a series\parallel guy with maybe a coil split tossed into the HSS. If you find any good links I be all ears. My searches have been relatively fruitless to this point Happy Trails Cynical One |
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Post by newey on Dec 4, 2008 23:21:45 GMT -5
Cynical1- AH! Here I thought this was just a sort of random, philosophical coffee shop musing, but you were actually headed somewheres with this. So, you're thinking HSS Strat with three V pots, and some series/parallel options? And, perhaps a J-bass with three pickups, and, presumably, also three volume pots? HMM. Well, the first thought that comes to mind is that with an HSS, you actually have 4 coils. And, if they are to be split, it might be nice to have an individual volume for each coil. 2 concentric pots could give you 4 vols, leaving an extra hole to put a master tone into. You also wouldn't need a switch for the coil split, the pots could do the work. |
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Post by cynical1 on Dec 5, 2008 1:54:17 GMT -5
Yes, Virginia, there really is an ulterior motive...
The bass idea was to take a split P-bass pickup and drop it between two existing single coil J-bass type pickups. The existing J-bass pickups have their own volume controls, and after 18 years with this bass I sort of got used to it.
I was looking for a way to use an independent volume control for the P-bass pickup, but just keep the one tone control for all three.
The only switching options would be series\parallel for all three.
The pickup switching is pretty simple.
2 J-bass on
1 P-bass on
All three on
The HSS is pretty simple too. Just a 5 way with a neck on switch. Then series\parallel and a N. coil/Humbucker/S.coil switch for the humbucker..
The thing that has me stumped is how to drop in the third volume control.
I'm sure it's a pretty simple modification, but I can't seem to find a schematic (interpret this as one that I can read...electronics illiterate on board here...pun intended) that I can use to as a jumping off point.
I do everything with bass\guitar electronics empirically as I lack any formal training or skill.
I began to wonder if the scarcity of designs implementing 3 volume controls indicated a problem with the concept, or just an dogged acceptance of existing established designs.
I still don't know... Never let anyone tell you that working on computers for 20 years makes you smart...
Happy Trails
Cynical One
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Post by ux4484 on Dec 5, 2008 13:13:43 GMT -5
I know I'm not the oldest one here, doesn't anyone remember Harmony's 3 volume/3 tone design. It's been recently reissued  in the Rocket and a few others. John Hiatt pulled one out this summer when I saw him when he played "Perfectly Good Guitar". |
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Post by andy on Dec 5, 2008 14:23:38 GMT -5
I began to wonder if the scarcity of designs implementing 3 volume controls indicated a problem with the concept, or just an dogged acceptance of existing established designs. Don't say we don't pay attention around here! This is starting to remind me of why I first joined the forum- I wanted to run three pickups to three outputs, and just needed to check about grounding them all. I'm no electrician, but I'm sure there must be a simple route to running three volumes to one tone, and running to a single output. With a volume for each pickup I would boldly suggest that switching is only really neccesary for quick on-stage switching, and if you dont mind a few split seconds more, just the three volumes will give you the options you are after and more. Of course you mention series/parallel, which is above me already, but if it makes it any easier to facilitate, I have found that the three volume, one tone arrangement works well on my three pickup SG. *PS* I just realised what I said- I have an SG with three volumes and a tone! It has a three way N+M/N+M+B/M+B switch, but I can post photos of the circuit if you think it will be any help? |
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Post by cynical1 on Dec 5, 2008 17:08:01 GMT -5
*PS* I just realized what I said- I have an SG with three volumes and a tone! It has a three way N+M/N+M+B/M+B switch, but I can post photos of the circuit if you think it will be any help? Thanks Andy. I'd love to see it. I've seen a few SG and Les Paul schematics, but honestly didn't see how to modify them for my own evil purposes. What I'm looking for on the bass is N+B\M\N+M+B. The single coil jazz type pickups are noisy as Hell even with the shielding unless they're both on. I figured I could use 4 wire SD or DiMarzio P bass in the middle and it wouldn't care. My pursuit continues... Happy Trails Cynical One |
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Post by ChrisK on Dec 5, 2008 18:19:50 GMT -5
Oh, you mean one of these (my Fender Stu Hamm Urge II bass);  It does not. Since M is on in all three positions, it is a plain old N/N+B/B switch with the middle volume pot always in-circuit. Yep, it's called the Fender Stu Hamm bass above. Here's the wiring (it doesn't quite do what you are asking for, and is an active bass). www.fender.com/support/diagrams/pdf_temp1/basses/0191500A/SD0191500APg2.pdfwww.fender.com/support/diagrams/pdf_temp1/basses/0191500A/SD0191500APg4.pdfIrrelevant. Fine, we can use this. Easy to add. Yeah, this can be done, it's not optimum, but it's the only choice for a single tone control and it works out on the J pickups I presume. More detail please. I might suggest a series/parallel switch for the J bass pickups if they are not single conductor plus shield. Both modes would still be hum canceling, but the series mode might give you the J bass tone anyway. If the J pickups are single conductor plus shield, I have a design that could put them in parallel, in series with the P pickup. Yep, this will use a DP3T ON-ON-ON switch. What does the "series/parallel" completely mean. |
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Post by ChrisK on Dec 5, 2008 19:04:01 GMT -5
Now, if you're willing to have the modes organized like this;
2 J-bass on
All three on
1 P-bass on
you can use a plain old LP-style selector switch.
In the J bass, both J volume pots are connected to the output jack. The tone control is also connected to the output jack.
Leave the tone control connected to the output jack.
The output jack is connected to the center terminal on the LP-style selector switch.
The common signal output connection for both J volume pots is connected to one end terminal on the LP-style selector switch.
The signal output connection for the volume pot for the P pickup is connected to the other end terminal on the LP-style selector switch.
Now, what does the "series/parallel" completely mean for the bass?
Can you post photos of the internal wiring?
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Post by cynical1 on Dec 6, 2008 2:20:13 GMT -5
Oh, you mean one of these (my Fender Stu Hamm Urge II bass); Yes, that's exactly what I was looking to do. Mine has the Peavey Super Ferrite pickups, but their sound is grossly under-rated. Yeah, I never went for active electronics. I'm like Newey...I never have a friggin' battery when I need one... ;D And you're right, it is irrelevant... Yes, the Foundation I have only uses a single tone control. I find I can tune the sound better with the two volume controls and roll the tone up or down to clean it up. Years of practice... OK, here's the layout before the idea to create more misery for myself and add another pickup and volume control. Pretty straight forward.  The Peavey pickups just have a red and black non-shielded pair. I haven't bought the P-bass pickup. I've been Bush-whacked and need to get a job first... The series\parallel just means that I'd set each pickup to run in series or parallel. Not sure I understand the question... Well, wasn't that fun. I'm thinking I put this in the wrong place... Happy Trails Cynical One |
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Post by newey on Dec 6, 2008 8:03:01 GMT -5
What Chris is asking is, "each pickup" in series/parallel with what? Do you want to realize all possible series combinations of 3 pickups? Or just some of the series options?
Since both J bass pickups are always on together, do you want to be able to combine these in series as well? or just series between the P-bass pup and the 2 J-bass pups?
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Post by andy on Dec 6, 2008 10:28:15 GMT -5
Cynical, between us we're cruising towards getting this thread moved elsewhere! Anway here is a shot of the innards of my three pickup, three volume, one tone SG. The tone would be the bottom right hand pot.  The long black wires are the pickup wires, so I tried for a bit of a close up with them pulled out of the way. Unfortunately the focus is way off, but if its any extra help...  Hope that's of use. |
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Post by cynical1 on Dec 6, 2008 13:07:38 GMT -5
What Chris is asking is, "each pickup" in series/parallel with what? Do you want to realize all possible series combinations of 3 pickups? Or just some of the series options? Since both J bass pickups are always on together, do you want to be able to combine these in series as well? or just series between the P-bass pup and the 2 J-bass pups? Hah! Holy bartender...now I get it... Man, sleep deprivation takes its toll... The diagram above details the series\parallel for the two jazz type pickups. The potential future P-bass pickup will be a four wire and will be set for series\parallel like any single humbucker. On the HSS I would probably set the two single coils to be series\parallel with each other, and rig the humbucker to go series\parallel with itself. Hope this clarifies it. Thanks for throwing me a rope newey... Happy Trails Cynical One |
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Post by ChrisK on Dec 6, 2008 13:31:54 GMT -5
The wire from the output jack "tip" goes to the wiper on the tone pot. I believe that this is incorrect and that it should go to the center terminal on the tone switch.
We will divide the circuit into two sections; the first is the J pickups, their series/parallel switch, and their two volume pots. There is a wire that goes between the left terminals on both volume pots (in your drawing), which we will call "J out". This is the output signal from both and it also currently goes to the center terminal on the tone switch.
The latter is the connection that will be interrupted by the new selector switch.
The second is the output jack, the tone pot, and the tone cap switch. We will call the connection to the output jack "tip" and the center terminal of the tone cap switch the "Out bus".
There is a new third section for the P pickup. I'm not sure that you should switch the P pickup into parallel. When just one string is vibrating over one coil, nothing is occurring in the other coil and it will appear as an inductor with a few thousand Ohms of impedance to ground and likely will attenuate the signal. You should hand twist the coil wires into parallel and test this before you commit to a separate switch for this mode.
This section is comprised of the P pickup and its volume pot, wired as the individual J pickups are wired to their respective volume pots (when in parallel). The "left" terminal of the P volume pot will be called "P out".
The new group selector switch (you will have to let me know what selection sequence you want since this determines the switch type) will select between section one, both sections, or section two. The common terminal on this switch goes to the "Out bus". Section one's "J out" goes to one selected terminal and section three's "P out" goes to the other.
Yep, this will use a DP3T ON-ON-ON switch.
Now, if you're willing to have the modes organized like this;
2 J-bass on
All three on
1 P-bass on
you can use a plain old LP-style selector switch (or a DP3T ON-ON-ON).
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Post by cynical1 on Dec 6, 2008 15:04:11 GMT -5
The wire from the output jack "tip" goes to the wiper on the tone pot. I believe that this is incorrect and that it should go to the center terminal on the tone switch. I pulled this mod from Wolf's site. Here's the image:  If this is wrong I'll need to correct the two guitar drawings too before I start soldering... The sequence makes no difference in switching order to me. It'll be new to me so whatever it starts out as is what I'll learn and the order you have detailed above is perfect. I'll need a little time to digest the rest of your post. I understand the concept, but when I start putting lines on a diagram I need it clear in my head first. The idea of dropping the series\parallel switch for the P-bass pickup makes perfect sense. Honestly, it was just "because it was there" more then actual need for the functionality. Give me some time to plod through Photoshop to clean up the drawing and I'll see if what you said is what I heard... Thanks again ChrisK for all your help. I hope the mothership doesn't come for you until I get all my projects are done... ;D Happy Trails Cynical One |
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Post by ChrisK on Dec 6, 2008 21:59:51 GMT -5
Wolf's image is not wrong. The way that you connected the output jack "tip" to it is wrong. To use Wolf's drawing in your guitar, what he calls "From volume control "hot" lead" is connected to the output jack "tip" terminal ( Out bus). This is a circuit that is in parallel with the output jack. He calls it this because this circuit is usually connected on the other (pickup) side of the volume pot. The output jack "tip" terminal also is connected to the center terminal on your new pickup selector switch ( Out bus).  |
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Post by cynical1 on Dec 6, 2008 23:22:58 GMT -5
One BIG Karma point for you, sir! I've been staring at this thing since I came in from feeding the horses...5 hours ago, and still hadn't grasped the concept you were talking about. Even after I saw your fix on my sketch it took a few minutes... Now it all makes sense... I've been toying with this idea for months...and got nowhere. I should have stayed in school... So the only things I have to get now is the pickup and a Les Paul 3 position switch... Man, if you're ever stranded in the snow in Wisconsin call me...I'll come and get you. Thanks again, ChrisK - Cynical One |
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Post by ChrisK on Dec 7, 2008 11:57:38 GMT -5
I'm glad that you see the plumbing now.
Uh-oh, now I know where you are. Oot there in Wisconsin, eh. Ya outta have aboot 2 feet of snow by now. (I can talk this way since my Mother is 1/2 Sweeedish.)
Well, my company Has a big presence in Minneapolis, but I only get to Wisconsin when someone makes a driving navigation error (we're in Wisconsin Sparky, you really did go the wrong way, eh).
I love the roads around Minneapolis; where else would you have 35 West (which goes North and South) AND 35 East (which goes North and South), and they are NOT related.
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Post by cynical1 on Dec 7, 2008 13:06:26 GMT -5
Uh-oh, now I know where you are. Oot there in Wisconsin, eh. Ya, hey der.. Actually I was born and raised in Chicago. I've moved across most of the country over the past 30 odd years, but we moved to Wisconsin because of the horses and alpaca. Sad commentary on your life when where you lived is based on how well the alfalfa grows... But on the bright side, I can drag my rig out to the barn and crank my a** off...and no one cares... Well, it does p*ss off the pigeons, though... Thanks again for all your brilliant insight. Happy Trails Cynical One |
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Post by cynical1 on Jan 15, 2009 2:23:22 GMT -5
Okay, I cleaned this up from my original atrocity and included the "free woman tone" mod ChrisK so graciously shared. Please feel free to double check this Rorschach diagram and let me know if I hosed anything up...  Everything should be detailed, but if I missed something, or had a blond moment feel free to point it out. Thanks again to ChrisK for helping me pound the dents out of this one. Happy Trails Cynical One |
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Post by ChrisK on Jan 15, 2009 20:28:56 GMT -5
A 15 second scan looks ok.
Gotta go, I have to drive 150 miles where it's only -4 degrees (unlike those up in the midweest where it's colder ootside.
And what's with this whole Swedish immigration thing and moving to Minnesoooooota just 'cuz it was like Sweeeeeden?
Hells bells guys, what aboot Florida? There IS a Norwegian settlement in Norge, Virginia.
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Post by cynical1 on Jan 15, 2009 22:13:55 GMT -5
Thanks ChrisK.
Yep, it was -180 with a 20 mph wind here all day...then it got dark and really cold outside...
I did wonder about the value on the treble bleed cap and resistor. I picked the 1000 pf capacitor in parallel with a 220K resistor based on what I read here...but that was for a guitar. Does it make a difference for a bass?
Thanks for keeping me honest ChrisK.
Happy Trails
Cynical One
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Post by pete12345 on Jan 18, 2009 11:28:03 GMT -5
Slight issue with the tone pot being wired directly across the output jack- turning that down will turn everything off. Simple to sort out though: the wire currently going from the jack tip to the tone pot should go to the center terminal of the LP switch instead.
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Post by cynical1 on Jan 18, 2009 15:43:08 GMT -5
Ya know, I was looking at that again myself after reading ChrisK's dissertation on the "Religion of Schematics" last night. The more I looked at it I tried to follow the "signal path" and began to wonder... So, I figured I'd revert back to ChrisK's original fix, and swap the caps out for .015 and .022. Sorry for the lack of schematic, but here's the final revised wiring diagram.  Thanks to all for pulling me out of it...again. Happy Trails Cynical One |
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Post by ChrisK on Jan 18, 2009 15:50:21 GMT -5
Yep. In theory, the ratio of the frequency ranges between the two instruments should be used to scale the treble bypass cap. If it's an octave lower, the cap should be an octave larger (Q.E.D.). The same metric could apply to the tone control cap(s) as well. Now, if you CAN find caps measured in octaves, please do let me know.... I got a guitar wiring book for Christmas that indicated that a "stronger" cap should be used. WTF  |
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Post by ChrisK on Jan 18, 2009 16:28:00 GMT -5
Try this. It wasn't the switch, it was the wayward connection to the output jack.  Octavius sez that you might want to use a 0.1 uF and a 0.047 uF cap for 0.1 uF, 0.030 uF, and 0.047 uF tone choices. |
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Post by cynical1 on Jan 18, 2009 17:07:39 GMT -5
Try this. It wasn't the switch, it was the wayward connection to the output jack. Thanks for pointing that out...I stared at it for an hour and gave up...this whole "signal path" thing is trickier then it sounds... Question: Won't the 0.1 uF cap be awfully bright for a bass? I began to wonder if the 0.047 uF might not be too bright... Thanks again. Happy Trails Cynical One |
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