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Post by cynical1 on Jul 23, 2016 23:34:04 GMT -5
So, after years of skillful procrastination, I've decided to operate on the Peavey Foundation bass. Some of you might recall me posting a diagram on this a couple of years ago. I've changed things since, so let me post the diagram as it stands now: To be precise, the location of the P-Bass pickup has also changed. After measuring where it would fit in between the two existing Super Ferrite pickups it's be too close to the bridge to perform the desired function, that being to increase the low end on this bass. Don't get me wrong, I like the way this bass sounds better than a Fender Jazz bass...but it always had a flatulence issue on the low end. Now the P-Bass pickup is going right up next to the neck at the 25th fret location. Sort of an inverse Billy Sheehan thing putting the P-Bass pickup where the EB Mudbucker should go, but the reasons are the same... That being said, I didn't want the new neck location to generate nothing but mud and rumble...so I thought about adding an OOP option...since there's room in the cavity... After looking around I found a few options. Plain Vanilla:While this is the easiest to install, it's not really what I'm after. French Vanilla:This has potential. I'm not sure how to tie this in with the existing series\parallel switch already in there. Half OOP Vanilla:Now, where I'm uncertain is which one of the two remaining flavors would give me what I'm looking for, namely, the ability to throw the P-Bass pickup out of phase with itself, so I can clean up the mud even if it's selected by itself. I've heard the last one on a Strat and love the way it filtered the low end, but left the mids alone with neck & middle selected. I remember something RoadTonever posted, but all his images left with mine apparently... So, any opinions, suggestions or words of warning? Happy Trails Cynical One
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Post by JohnH on Jul 24, 2016 14:59:29 GMT -5
Looking forward to seeing another master project!
I reckon for those wiring options, unless you already know which sound best, it would be best to plan for a temporary wire-up to try them out before passing any point that requires a commitment one way or another.
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Post by sumgai on Jul 24, 2016 16:06:34 GMT -5
cone,
After dissecting your treatise, I think it would be best if you relabeled the diagram to show that the Shaller PBX is now in the Neck position, as per your description of it "going right up next to the neck at the 25th fret location". As I look back and forth between that sentence and your diagram labels, and try to keep everything straight, my head starts to hurt sumpin' awful.
At that point, you can make sure that your labels all match up with your intended switching logic.
-----------
BTW, I don't recall ever seeing an LP-type toggle switch that can turn on a pickup in the middle position, let alone turn it off in either side position - you got a source for such a beast? (And no, the switch from an LP Special (with 3 Hb pups) will not do the job. In the middle position, it turned on the Mid pup, true enough, but it also turned off the Neck pup - not what you're after, amiright?) Right about now, I'm thinking that if appearance is a key issue, then a Freeway switch might be just the ticket.
OTOH, if appearance is not an issue, or if cost is an issue, then a bone-stock Strat-style blade/lever switch can do the job with ease.
Also, relying on one or more pots to do a blending job might get you over the hump... just a thought.
HTH
sumgai
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Post by cynical1 on Jul 24, 2016 18:33:39 GMT -5
Looking forward to seeing another master project! I reckon for those wiring options, unless you already know which sound best, it would be best to plan for a temporary wire-up to try them out before passing any point that requires a commitment one way or another. Well, I'm not planning on doing anything cosmetic, except on the neck...but that's another post entirely. This bass is 28 years old and has earned every battle scar it has. My intention was to be able to switch the neck P-Bass pickup in and out of phase with itself to try and tame the boomy muddy tone a bass pickup tends to get in this spot. The half out of phase option seems like what I'm looking for. What I'm really curious about is how it will react with the other two pickups when all are selected. Another question is on the capacitor used on the HOOP switch. Lawrence's diagram calls for a .022 uf capacitor...just wondering if that changes when used on a bass? As you said, it's trial and error. RoadToNever went down this path in a post here. Sadly, all of his image links are broken, so I can only guess what finally worked for him. Happy Trails Cynical One
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Post by cynical1 on Jul 24, 2016 18:56:40 GMT -5
cone,
After dissecting your treatise, I think it would be best if you relabeled the diagram to show that the Shaller PBX is now in the Neck position, as per your description of it "going right up next to the neck at the 25th fret location". As I look back and forth between that sentence and your diagram labels, and try to keep everything straight, my head starts to hurt sumpin' awful. Fair point...drawing redone to reflect new pickup location: The switch is supposed to turn the neck (P-Bass) pickup on in the top position, the middle and bridge Super Ferrite pickups in the down position, then all three in the middle position. I've got room in the cavity to stuff a standard LP switch. The Freeway switch seems like overkill, and I hate cutting the damn slot for a 5 way switch since I don't have the fixture anymore. And there really is no "blending" going on, at least no more than you'd find on a standard Jazz bass. It's just a concentric stacked volume 250K pot for the individual control of the middle and bridge, a single 250K pot for the neck volume and a common 250K tone pot. The phasing option may be the wrong way to go here...I don't know. Again, all I'm looking for is a way to tame the neck mudbeast when the mood strikes. This Schaller pickup is one of the original ones made for Schaller by DiMarzio...and it's hotter than a typical P_Bass pickup...and hotter than the Super Ferrites when paired and dimed as well. If there's a better way to pull the mud out of the neck position at will I'm all ears here. Happy Trails Cynical One
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Post by sumgai on Jul 24, 2016 20:30:30 GMT -5
cwon,
No, your ideas are OK, vis-a-vis knocking down the muddiness. The only thing I'd add here is that the two coils of the Shaller should be wired in parallel, not in series. You might recall that series connections tend to sound less trebly, and hence more bassy/mid-rangey, than parallel connections. Plus, a parallel connection will reduce, by a small amount, the pickup's total output level. From your descriptions so far, I think the S/P switch can safely go away.
That said, adding a cap in series with a coil will cut the lower frequencies, true. The value of 0.022mf seems a bit large to me, even for a bass, but it should be easy to experiment in this department. Simply run two wires out from under the pickguard, and connect whatever cap(s) you have on hand. Lather, rinse and repeat with different values until you arrive at your ultimate tone.
As to this whole business of HOoP and regular OoP, I think you should experiment with that too. Instead of running just 2 wires out to the finger-touchable world, run 4 wires outside of the axe (one for each pup lead, one for Hot and one for signal return (ground)). Now you can hook up the switch as well as the cap, and try it just about every way possible - OoP, HOoP or normal, as well as what value of cap to use. Plan on doing some extensive testing, as you may end up deciding to use the cap without the OoP option (meaning, no HOoP), or potentially using just the OoP option with no cap - who knows?
HTH
sumgai
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Post by sumgai on Jul 24, 2016 21:42:53 GMT -5
c,
(after a filling dinner.....)
I see that I didn't address your pickup selector, which I thought was going to be an issue. It's not, the way you've drawn it. As with 95% of all J-basses, you'll simply blend between the Mid and Bridge pairing. Not to mention, the way you've done it now, the Bridge Vol control is out of the picture when Series is selected, leaving only the Mid Volume in action. Less loading, simpler operation, what's not to like?
Overall, tres elegant, earning you a Plus 1.
sumgai
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Post by JohnH on Jul 25, 2016 0:24:29 GMT -5
Another un-mud option could be a bass-cut knob, as part of a tone control setup along the lines of G&L PTB wiring.
A nice feature of it is that causes no degradation when at zero ohms. Values could be suggested appropriate for a bass, and confirmed by test.
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Post by cynical1 on Jul 25, 2016 13:58:37 GMT -5
Another un-mud option could be a bass-cut knob, as part of a tone control setup along the lines of G&L PTB wiring. A nice feature of it is that causes no degradation when at zero ohms. Values could be suggested appropriate for a bass, and confirmed by test. I looked at this after I decided to move the location of the P-Bass pickup from it's typical location of 11-5/8" (a hair past the 32nd fret)from the 12th fret-to-pickup centerline (since the existing Super Ferrite "neck" pickup is at 11" 12th fret to centerline) to what could only be termed "EB0 country" at a hair under 9" (approx. the 25nd fret) from the 12th fret-to-pickup centerline. I like the way you can dial in the bass and treble. Face value says it's perfect for what I want to do. My concern with this is that the existing Peavey pickups do not have a problem with excessive low end rumble. I like the way they work together and aside from adding a series option to the pair I've left their original design alone. Combining them into a G&L PTB style tone circuit that filters out the bass is not a requirement for these two pickups. I'd have to find room for two pots to isolate the added p-bass pickup's tone circuit from the existing Peavey pickups to get what I'm looking for...and there isn't enough room at the Inn for that. Fender has their stacked 250K\500K pot, which I could squeeze in, but the G&L PTB design calls for a 500K and 1MEG pot. Granted, the relationship appears to be the same, but I'm just the wood butcher around here and don't rate my electrical knowledge too high. I'm still in the dark about why Wolf's HOOP diagram has no cap and Lawrence's does. I'm still wondering if there's a way to handle phasing like splitting a pickup...namely a Spin-A-Phase option. And I'm still wondering about how to incorporate any of these designs into the neck pickup and still preserve the series\parallel option...as you will notice by their conspicuous absence in my drawings above... My brain hurts... Happy Trails Cynical One
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Post by sumgai on Jul 25, 2016 14:34:00 GMT -5
^^^^ 'sfunny, I didn't see any diagram from 1728 in this thread that specifically mentions HOoP, with or without a cap. On his website, wolf speaks only to OoP, as far as I can tell. But then again, I didn't take the time to read absolutely everything there, that'd be an all-day adventure!
By its very definition, a cap is required to achieve HOoP, in one fashion or another. Mr. Stitch has it correctly, according to your posted copy of his diagram. The only thing is, to me at least, is the player is locked into having the cap inserted into the signal path only when the pickup is truly OoP to another pickup. I think that each player should be able to try it both ways (adding a cap in OoP or in normal mode), and adjust his circuitry accordingly.
I guess that I'm not a fan of removing tonal options, that's all.
sumgai
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Post by cynical1 on Jul 25, 2016 15:51:39 GMT -5
^^^^ 'sfunny, I didn't see any diagram from 1728 in this thread that specifically mentions HOoP, with or without a cap. On his website, wolf speaks only to OoP, as far as I can tell. But then again, I didn't take the time to read absolutely everything there, that'd be an all-day adventure! OK, HOOP was my bad. Wolf describes it as "In and Out of Phase with itself" Different beast entirely...and probably more inline with what I'm looking to do. You make a good point in dropping the series\parallel on the p-bass neck pickup. It would free up a bit of room to drop the G & L PTB circuit in place The more I think about it, the G & L circuit does seem to be more practical. OOP is fun with guitars, but tends to be a novelty on a bass. I guess I'm more curious about what it'll do in OOP in series or parallel mode. As you know, I play with a lot of different pedals. Parallel OOP with some gain stacking can be very amusing through a wah wah pedal...as you said, almost like a comb filter... Again, not very practical for a bass, but it might be fun to experiment. No matter what I do to the p-bass, as long as I keep it separate from the original Peavey pickups I can still preserve what I like best about this bass. The trick for me now is to incorporate a pickup into a location it was never intended to go and still offer some valid improvements to the basses performance. I believe the operative phrase here is "Do No Harm". You're in good company there. That's the whole point in slapping the 3rd pickup into this bass. For some more history that you could probably live without, the Peavey Foundation is another clone of the Jazz bass design. For the uninitiated, this is pertinent as Fender changed the locations of the bridge pickup in the 70's, moving it 3/8" closer to the bridge. Measuring from the 12th fret to the centerline of the pickup, here's the skinny: 60's Jazz Bass: Neck: 10 7/8" Bridge: 14 1/2" 70's Jazz Bass: Neck: 10 7/8" Bridge: 14 7/8" The folks at Peavey must have taken this move by Leo as a sign from on high, as they added 1/8" to the 70's Jazz setup for the Foundation: Peavey Foundation: Neck: 11" Bridge: 15" What this all translates into is a bass with a very clean and punchy tone with great harmonics...if you're playing above the 3rd fret. It's always had a flatulent rubberband like quality to anything played on the E or A above the 3rd fret...but I never played there all that much when I was using it regularly and could always tweak the amp when needed to try and cover as much of the issue as possible. Originally, I was going the p-bass pickup in-between the two Super Ferrite pickups. On closer scrutiny, this would have only exacerbated the issue, as it would have put the p-bass pickup at about 13" from the 12th fret to the centerline of the pickup...no low end to be found around those parts... So, it was time to think about why I wanted to add the 3rd pickup in the first place. We all know why it's called a Mudbucker. I remembered replacing EB0 pickups out for p-bass pickups in the past, and while it cleaned up a lot of the issue, it still left something to be desired. I'm not looking to remove tonality. I'm looking for a way to give this bass what it always lacked, while at the same time, making the addition of the 3rd pickup as useful as possible rather than a another problem to fix later. I may play with the full on rumble stuff from time to time, but I see this pickup being subtly blended into the other two more often then it being an entity all onto itself. That said, the more I can do to it by itself before it gets blended the more appealing the idea becomes. Make sense? Happy Trails Cynical One
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Post by cynical1 on Jul 25, 2016 17:08:55 GMT -5
Not to mention, the way you've done it now, the Bridge Vol control is out of the picture when Series is selected, leaving only the Mid Volume in action. Less loading, simpler operation, what's not to like?
Overall, tres elegant, earning you a Plus 1. This was just one of the many gifts given out by chrisk...for the exact reasons you mention. Just to keep things honest... HTC1
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Post by cynical1 on Jul 25, 2016 20:44:01 GMT -5
OK, does this make any sense? Still not sure about the resistor. Some diagrams showed it, some didn't...I didn't either... Not sure about most of this PTB thing... Comments welcome HTC1
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Post by newey on Jul 25, 2016 23:01:15 GMT -5
This is a quick glance after a couple of glasses of Chardonnay, but FWIW I think your diagram will generally do as intended. I question only the operation of the bridge and neck Vol. controls when those pickups are in series- It seems to me that both these pots would be in circuit in series mode, with possible tonal effect. But I could be wrong on that. Wiring wise, everything seems OK. Do I hear a cheer for a Strat SC in the neck position? (As you know, I have a soft spot in this regard . . .) You want brightness, lack of mud? Ditch the P-bass split coil for a single-coil, as in the original P-Bass. Of course, it won't be hum-cancelling, but hey, you're going to shield the whole shebang anyway, right? The EBO "muddiness" always seemed to me to be more due to the fact that it was a humbucker at that position, moreso than the numerology of the positioning. I've always liked the SG/EB style of body, so maybe there's a bass project in my future- swapping out the HB in an EB for a vintage P-bass SC.
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Post by sumgai on Jul 26, 2016 1:12:44 GMT -5
newey,
In early versions of the EB0/EB3, the Neck pup was a single coil, wound pretty much like a P90 or a Jazzmaster - squatty, for lack of a more formal word. IMO, the muddiness came from being wound much like a "jazz" pickup... all warm and fuzzy, the tone not meant to be sharp or to ring out. But I agree, the Hb versions that came later did the bass no favors either.
I don't see where the Neck and the Bridge will ever be combined in series, only the Middle can achieve series with the Bridge. And at that point, the Bridge Vol control will be switched out of the picture.
c1,
I see only three points to point out:
1) The dual 250K/500K pot shows the Treble side as having the cap on the wiper, and the input on the left-most terminal - I think the input should be moved over to the right-most terminal, or else the control is going to work backwards from what you expect.
2) I see that the HOoP switch is still not "drawn in" - does this mean that the aforementioned dual pot will be taking its place?
3) Having the Master and the Neck treble controls in parallel may yield unintended results. Unlike resistors in parallel (where the total value goes down), capacitors in parallel will increase the total apparent value. Be prepared for one or both controls to be a bit "touchy".
HTH
sumgai
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Post by newey on Jul 26, 2016 5:11:40 GMT -5
Sorry, I meant to type "neck and middle", not "neck and bridge".
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Post by cynical1 on Jul 26, 2016 12:27:08 GMT -5
Newey - It's not that I'm looking to brighten up the bass...it's bright enough already. The task at hand it working to remove the intrinsic rumble and mud that comes with putting a pickup this close to the neck on a bass. Rickenbacker and Gibson did it. One made a classic, one made a novelty, IMHO. I think SG hit the "mud" thing on the head when he said Gibson overwound the Hell out of these pickup. The original EB pickups actually had the pole pieces on the side with the coils and magnets piled in next to them to allow for the massive overwound coil: If you ever see one of these, grab it. People pay insane amounts of money for these things.Moving along, the over winding, position and scale length all contribute to the muddy tone of the original EB bass. Over the years you'll notice that Gibson moved the pickup closer to the bridge, added a bridge pickup and increased the scale length from 30.5" out to 34" before they relegated the EB series over to Epiphone. I expect to gain a small improvement due to the 34" scale length of the Foundation bass. Using a P-Bass pickup instead of the EB design will also decrease the mudflow a bit. If I get this right I should be able to take an instrument I've loved for over 25 years and give it something it truly needs...namely, some balls. Happy Trails - Cynical One
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Post by cynical1 on Jul 26, 2016 12:56:55 GMT -5
I can fix this. I looked at quite a few variations on this theme and apparently just got lost in EmpiricalLand... I will fix this.
Yeah, the more I thought about it, the HOOP began to resemble a "one trick pony". It was a solution, granted, but it wasn't the best one for the application.
Pardon me while I derail my own thread here...
Yeah, now that you mention it, I've done this to myself before. The more I look at it, the more I'm leaning towards just discarding the phase option and using the PTB circuit as the common tone controls.
I'm glad I posted this phasing idea, as sometimes you get lost in your own concept and those blinders prevent you from seeing other more valid options.
If I consider why I'm adding this extra pickup, namely more bottom end, the phasing option really was a little short sighted. JohnH's idea of using the PTB circuit seems to fit the application much better than a phasing option...although a "Spin-A-Phase" module would be fun to play with...
I'll re-draw this today, but I have one question. Some of these PTB design have a 1M resister in parallel with the .022uf capacitor going to ground. Is this necessary?
OK, one more question, which I wouldn't have to ask IF I understood how to use JohnH's GuitarFreak tool: Since I'm changing the values of the pots in this circuit from 500K\1M to 250K\500K, is the halving relationship the same with the capacitors and resistors in the circuit?
Happy Trails
Cynical One
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Post by sumgai on Jul 26, 2016 14:09:02 GMT -5
c1,
All good so far....
... OK, one more question, which I wouldn't have to ask IF I understood how to use JohnH's GuitarFreak tool: Since I'm changing the values of the pots in this circuit from 500K\1M to 250K\500K, is the halving relationship the same with the capacitors and resistors in the circuit?
No, sorry to say, it's the other way around. The frequency response of a tonal circuit is predicated on the formula:
Fc = 1 / (2 pi R C)
which shows us that the resistor and capacitor are both under the dividing line. That means that if you reduce the value of R, then C will need to be increased by the same percentage, providing that you want to maintain the same cutoff frequency (also known as the knee point, on the graph). Stated another way, reducing R by one half will move the cutoff point one octave down, and doubling R will move it up an octave - ditto for C.
Thanks to all this mumbo-jumbo, we can manipulate the values of R and/or C to accommodate any "spare" parts in our junk box, and get reasonably close to the desired frequency response.
HTH
sumgai
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Post by JohnH on Jul 26, 2016 15:16:30 GMT -5
I can help with exploring values for the PTB one bass. Are you having the PTB controls and another master tone after the volume? a complicating factor, possibly losing some edge. For the Bass cut part of the PTB, often the largest pot value is best to get the greatest bass-cut range, like 1M instead of 500k. I don't think it needs a resistor in parallel with the cap, and the cap value is up for experiment. If you haven't read it, take a look at this: guitarnuts2.proboards.com/thread/7172/bass-cut-ptb-system
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Post by sumgai on Jul 26, 2016 16:30:57 GMT -5
c1,
As John points out just above, the higher the pot value in the Bass Control circuit, the better the action across the entire rotational range. However, pay attention to that pot's stated value: 1MegC... it's that "C" that will get you. Here, it means "reverse audio taper", or IOW, reverse log taper. This reverse taper will act in what you, as the user, would consider a smooth curvature of operation, whereas a normal taper would be sudden and drastic. A linear taper isn't not quite so bad, but still not quite up to par.
Go ahead and use whatever you've already got on-hand, and see what happens. In truth, it's all a matter of taste and expectations - you may not think it's so bad with a "normal" taper.
HTH
sumgai
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Post by JohnH on Jul 26, 2016 17:02:17 GMT -5
Its a good point about pot taper, and a reverse-audio C type is often considered preferrable for the bass cut. Then it can be wired with max bass, no cut at 10 and max cut at 0.
But if I was doing this only with parts from the spares box, Id use a standard A-type audio =log taper pot, but wire the outer lugs oppositely. So then max bass cut is at 10. Its the same smooth transition as the C type, but in reverse.
Then I would try to get used to the concept that both treble and bass controls would work consistently, in terms of 10 would in both cases be the brighter sound (max treble or min bass) and 0 would be the darkest sound ( min treble or max bass)
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Post by cynical1 on Jul 26, 2016 19:07:08 GMT -5
That would be greatly appreciated. I tried running this through your GuitarFreak, but it's a lot like giving a laser to a 5 year old...
Right now the plan is to go with a 250K\500K stacked Fender pot for this.
The capacitor values, based on SG's input to halve everything, would be dropped to either:
.022uf on the Treble side to .033uf or .047uf .0022uf on the Bass side to .0033uf or .0047uf
Again, venturing deep in EmpiricalLand on these values...
While the idea looked promising of running two tone controls, weighing the downside against it, knowing damn well this thing will spend the majority of it's life in parallel across the board, I'm going to lose the master tone control and move the PTB tone circuit into the Master Tone control spot. I just need to redo the drawing to keep it straight in my mind.
That's the way I did it...I'm pretty sure... I just substituted pot values to 250K\500K based on availability of parts I could find online...and within economic reason....
The more I look at this the more I like it. This genuinely addresses the main hurdle to get over in adding the 3rd pickup at the 25th fret on a bass, but doesn't screw with anything you don't want it to.
I was reading it last night and again this morning. That's what finally made me wake up and realize what this PTB circuit can do in this bass. Glad someone left breadcrumbs...
Happy Trails -
Cynical One
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Post by cynical1 on Jul 26, 2016 19:24:52 GMT -5
This is what I get for starting a reply at 8:30AM and finishing it at 5:00PM...
OK, I'm guessing this reverse audio taper is going to be impossible to find in a stacked pot...so, let's go with the idea that I have room for one more pot, allowing me to use two pots, as seems typical, for the PTB circuit.
With this new option I am now free to select any pot value and taper I want. Taking this into consideration, would I be better off going with the original 500K\1M reverse taper pair over the 250K\500K values I substituted?
Feel free to explain it like I'm 5.
Happy Trails -
Cynical One
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Post by cynical1 on Jul 27, 2016 21:24:44 GMT -5
I sat and looked at a couple of versions of the PTB circuit, and here's where I wound up: I think everything is good...however...I'm not sure if the reverse audio bass pot is wired correctly. I think everything else is good... The only other thing I'm still unsure of is the values for the pots and capacitors...hence the TBD status in the drawing. Comments welcome. Happy Trails Cynical One
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col
format tables
Posts: 472
Likes: 25
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Post by col on Jul 28, 2016 0:42:53 GMT -5
C1, If all else fails, you can order what you want from here: www.omeg.co.uk/products.htm#potsThough, as I recall, there is a 10 unit minimum order. You could always try ebaying your surplus.
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Post by sumgai on Jul 28, 2016 2:42:10 GMT -5
I just realized....
This thing is gonna be using the so-called "backwards" wiring schema for the Mid and Bridge Vol pots. That means that the reaction of two tone controls will be strongly affected, as the pot is rotated away from full on (10 on the knob).
John, if you're gonna spice this gizmo, don't forget that little detail.
sumgai
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Post by JohnH on Jul 28, 2016 2:55:34 GMT -5
I know, I saw that too. But there's more hairs as well:
The bass-cut in a PTB relys on being before the volume pot, so that the natural loading from the 250k pot resistance can bring down the bass level in conjunction with the bass-cut cap.
After the various volume pots as here, it's lost the 'R' part of the relevant RC high-pass filter, other than the unknown and much higher amp input Z.
Will think of other suggestions to suggest....
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Post by cynical1 on Jul 28, 2016 12:19:26 GMT -5
This thing is gonna be using the so-called "backwards" wiring schema for the Mid and Bridge Vol pots. That means that the reaction of two tone controls will be strongly affected, as the pot is rotated away from full on (10 on the knob). I can swap the wires on the middle and bridge pots. Nothing has been soldered yet and no parts have been purchased. But there's more hairs as well: The bass-cut in a PTB relys on being before the volume pot, so that the natural loading from the 250k pot resistance can bring down the bass level in conjunction with the bass-cut cap. After the various volume pots as here, it's lost the 'R' part of the relevant RC high-pass filter, other than the unknown and much higher amp input Z. That explains why most of the drawings, except the ones that were wrong, didn't make sense to me. If I understand you correctly, I'm going to need a lot more pots to make this work. I have room in the cavity for another pot, a Les Paul switch and two small DPDT switches...maybe room for one more pot, but after that the Inn is full. Man, and it looked so promising there for a while... HTC1
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Post by JohnH on Jul 28, 2016 15:27:51 GMT -5
The kind of thing that might work with the PTB concept is if you could condense the inpedendent volume pots for each of the 3 pickups down into just two channels, one each for say, B/M or N. Then each has its own PTB system either on a dual-ganged or dual-concentric pot
Channel BM: selects and control the B and M Ferrite pickups.
After the pickups is an on-on-on switch to provide series, B or parallel (so no M only in this scenario). This goes to a treble cut control, bass cut control then volume
Channel N: controls the P-bass N pickup
A dpdt selects series or parallel. This goes to a treble cut control, bass cut control then volume
.
Final switch: Les Paul toggle switch to output to select, BM, BM+N or N
This could be a neat arrangement. The pots could be just three dual concentric, for volume, treble and bass eg: All top knobs do BM and all lower knobs do N.
There'd then be room for one more toy. Could be an overall phase switch between BM and N channels (I'd do that), or another switch in the BM system to allow M only.
Potential hairs on this idea: The bass controls would presumably not be available as dual reverse log (TBC). So need to choose either linear or standard log.
If you love the inside-out, backwards wiring of independent volume pots, with consequent treble loss at low volume, then this isnt it. Its conventional LP-style forwards wiring. It comes with the (non)issue that if you select both channels on the toggle and roll one to zero, all is cut off. But I think the independent wiring may be more common on basses than guitars.
But overall, I think it could comply with the main design princples laid down in our constitution.
Any good? Can develop it further if you think it has more 'legs' than it has 'hairs'.
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