Raz59
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Post by Raz59 on Apr 15, 2010 16:51:31 GMT -5
Hi everyone, It's probably not a good idea to start posting in these forums by asking for help, so I apologize in advance... I'm requesting help to build Borsanova's Les Paul Twenty-Dual mix schematic in a more newbie (me) friendly way. I've created a starting point based on a Seymour Duncan diagram. I only did the basic connections that I think are necessary. I didn't add anything else because I didn't understand Borsanova's schematic. The wires use the Seymour Duncan color code: And one last thing. JohnH suggested a treble bleed mod on the volume pots and that does its job and all... But is it possible to wire Borsanova's diagram with the 50's wiring concept? By that, I mean soldering the capacitors to the middle lugs of the volume pots (where the selector switch wire is soldered to) and to the right lugs on the tone pots (and soldering the middle lugs to the back of the pot) I know 50's wiring has the flaw of losing volume when turning down the tone pots, but I would like this Jimmy Page mod to act like a vintage Les Paul harness when I roll down the volume and tone controls. I hope no one minds my request. Thanks in advance.
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Post by newey on Apr 15, 2010 18:57:16 GMT -5
raz- Hello and welcome! First off, please downsize your diagram so that horizontal scrolling isn't needed. Not all of us have widescreen monitors! Second, you've resurrected a classic diagram from Borsanova there- a blast from our past, so to speak. We haven't heard from him in years. But we can certainly answer any specific questions you may have. What didn't you understand about his diagram? I'll grant you, it's a bit hard on the eyes- and fairly complex, too. We're happy to help, but we need to know where you are lost on this particular mountain before we can send out the St. Bernards. Now, if it's the wiring colors that are throwing you, Borsanova doesn't show them since they will vary with different pickups. He does, however, number the connections from 1 to 8. 2 and 3 on the bridge pup, and 6 and 7 on the neck. These correspond to the red and white wires on the SD HBs, desinated as "North Finish" and "South Finish". Wires 1 and 5 then correspond to the "North Start" and 4 and 8 to the "South Start". But these don't really matter, you could swap the wires 'round, from 1 to 4, or 5 and 8, and it would still work as advertised, so long as you are consistent between the 2 pickups. As far as the switching scheme is concerned, it's mostly the Jimmy Page mod- until you get to the P/P pots on the Tone controls. There, he uses a little trick called "binary tree switching" to get both HBs as SCs, and also to put the bridge HB into a parallel coil configuration. Binary Tree switchingBorsanova's use of the concept is a little different than the one ChrisK diagrammed there, but the basic switching principle is the same.
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Raz59
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Post by Raz59 on Apr 15, 2010 19:19:33 GMT -5
Sorry about the large image, I think it's fixed now.
First off, what I don't understand is why are there 4 capacitors in this design. That is if the 4 round elements soldered to the lugs are capacitors, I might be misinterpreting it. Then, I'm not sure which humbucker is the neck or bridge humbucker, so that threw me off too. And because I don't have knowledge on the subject, I don't understand what Borsanova means when 4 wires come together and form a "circle".
So I'm seeking someone's help to draw that diagram again, but with the images from Seymour Duncan. Perhaps I'm asking too much
It's a shame that Borsanova became inactive. This schematic got my attention because it seemed to keep the pots with the normal function of the pots without adding anything too "radical".
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Post by newey on Apr 15, 2010 19:44:04 GMT -5
Thanks for fixing that!
You're not misinterpreting it. Indeed there are 4 caps.
The capacitors on the tone pots are there, well, because a tone pot has to have one to work. The ones on the volume pots are there as a "treble rolloff" mod, the better to keep the highs in as the volume is reduced. These are optional but desireable. I believe JohnH recommends both a cap and a resistor for this job.
The pickups aren't labelled, but each pickup's respective V and T pots are labelled. You can trace the wires from the bridge volume pot back to the bridge pickup, same with the neck.
I'm not sure what you mean by this. The only circles I see on the diagram are the vol and tone pots, and the output jack.
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Raz59
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Post by Raz59 on Apr 15, 2010 20:04:45 GMT -5
Ok, I identified both humbuckers now. I mean these parts: And about the extra capacitors on the volume pots. Usually when you need a treble bleed, it's because we're dealing with "modern wiring". JohnH wrote that 50's wiring (what I want) and modern wiring "relates to whether the tone controls are wired before or after the volume controls". But I don't really understand that and can't translate it to a complex wiring like Borsanova's. Could someone help?
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Post by newey on Apr 15, 2010 20:30:34 GMT -5
Aha! The little dot there (well, it's not really a dot as Bors shows it, but same idea) means that the wires form a connection at that point.
Looking further, you'll see that, at all the places where those connections exist, they all get routed to the same place- ground.
This section of the circuit can be called the "grounding buss" for that reason.
The switching scheme is a separate module from the volume and tone controls. You can implement '50s wiring if you want- the volume and tone controls together form a separate module.
I'm not able to help with a diagram for you at the moment- leaving town tomorrow for a few days. But, you'll understand the concepts better if you take a stab at it yourself. We'll correct any errors you make, and along the way, at some point, you'll have an "Aha!" moment when it'll all fall into place.
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Raz59
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Post by Raz59 on Apr 15, 2010 21:42:40 GMT -5
I've tried to do the wiring myself with the concepts of where the capacitors go in relatation to the selector switch wires. The problem is, I don't know if I can replace a jumper with the capacitor itself or what to do when one path becomes redundant (because I start off with the capacitors between volume and neck pots): So I really need help, I feel I'm lacking some concepts
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Post by newey on Apr 15, 2010 23:12:27 GMT -5
Raz-
OK, it's a start. There are some problems, however.
For the moment, ignore the switching, and just focus on the connections between the pots.
You only have the cap, and nothing else, connected to the tone pots. They need another connection to make a circuit. In this case, the other connection is from the center lug to ground, which usually means it's grounded to the back of the pot.
BTW, you need to pay attention to the clockwise and counterclockwise lugs on the pots. If you pick the wrong one, your control(s) will work backwards, lefty style. Most pots have a marking to show the CW terminal. If you do wire any of them up backwards, it's easily fixed, just move the wire to the opposite lug.
Once you have the Vol and tones set up, you've made a module- a '59 LP 2V2T module. You then must figure out how to wire it into Borsa's diagram. This is where the switches come into play.
You haven't wired the neck pickup yet. The leads from the neck pickup are wired first to the phase switch- that's the one with the wires making an "X" across it. Start from there, and trace the connections out as per the diagram, and repost your results.
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Raz59
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Post by Raz59 on Apr 16, 2010 6:45:56 GMT -5
So I need to solder at least one lug to the back of the pot? Ok, I soldered the middle lugs of the tone pots to the back of the pot. I also soldered the right lug of the neck volume pot to the back, but I can't do it to the bridge pot because, according to Borsanova's diagram, all lugs are being used. I started from where I left off, and I wired the neck pickup as per the diagram. I'm following it blindly...and again, I don't know what to with the bridge tone cap. Borsanova wired it from the neck pot lug to the neck push/pull lug and then a jumper went to the neck volume push/pull lug...and from that lug to the volume pot. I'll post what I've done so far:
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Post by JohnH on Apr 16, 2010 8:58:38 GMT -5
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Raz59
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Post by Raz59 on Apr 16, 2010 10:18:19 GMT -5
Borsanova's design seems to have the extra "parallel humbucker" sound for the bridge humbucker, this is my main reason. And when in "System Series" mode, the toggleswitch will never act as a killswitch (I think yours does this too). Another reason that I chose this particular design is that, when in "System Series", each volume pot is still individual, meaning there's no Master Volume, so I can control how much of each humbucker is in the mix. So right now I'm trying to figure out how draw Borsanova's design in a more newbie friendly way and also wire it 50's style to avoid installing extra resistors and capacitors. But if you know of a more recent design that's close or exactly what I want, please point the way! So far I haven't found anything. EDIT: To avoid double-posting-- I've made all the connections I could (except for the bare wire of both pickups, which I don't know where to put). newey said I had to be careful not to wire a pot backwards...so taking that in mind, I moved the bridge pickup's green wire to the left lug so I could solder the right lug to the back of the pot. I also grounded all pots with the ground wire from the bridge...and this completes my attempt at it. I have a feeling this won't work...and worst of all, I don't know why! Requesting help, please!
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Post by JohnH on Apr 16, 2010 18:00:23 GMT -5
OK, I understand, and B's design was clever in providing the bridge parallel feature. I also like, as on my designs, to keep the two volume and tone pots seperate in series so you can control each pup seperately.
You have had a good go at the diagram, so ill review it.
cheers
John
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Raz59
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Post by Raz59 on Apr 16, 2010 18:37:54 GMT -5
Thanks for helping John!
I did have a go at the diagram, yes. I'm not so sure about the "good" part but it was an honest go from my part.
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Post by JohnH on Apr 16, 2010 19:10:19 GMT -5
hmmmm....im seeing problems everywhere! Your version and his use differnt positions for the main controls (yours being more standard), but as you thought, there are places where you have not captured his intent (easy example, the push/pull on the neck tone, ie the lower right one, has nothing on its centre right lug, so does nothing).
So I went back to B's diagram, and I see problems there too! Apart from the control layout (which can be translated), he has the lugs on the volume pots reversed (assuming viewed from the back, which is how these diagram should be done), also, when you engage series mode by pulling BV, the neck vol does nothing much.
So the problem we have is matching a new wiring diagram with some issues, to an existing one with different issues, and no schematic that actually explains how it works, and no Borsanova to help resolve it.
So, as the irishman stated when asked the way to Dublin "...this is the wrong place to start from!"
I will try to work out what was intended in schematic form (ie electronic symbols showing connections, may not mean much but its the only way I can think of these things), then we can think up a wiring diagram.
As to how to draw it, your seymour duncan blank version is useful, can you post one with no wires at all, just the pups and controls? The neatest way I find to draw diagrams is with Word, and your base image can be placed in the background, then curved lines added to connect it up.
John
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Post by JohnH on Apr 16, 2010 19:14:08 GMT -5
Also, can you confirm that you prefer the standard layout of V and T controls on a les paul, and do you want the coil cut controls on the tone pots?
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Raz59
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Post by Raz59 on Apr 16, 2010 19:38:19 GMT -5
You want a blank version with just the elements? Sure, that's the easy part! As far as my preferences go...well, I'm aiming for a standard Les Paul when all controls are down, so yes, standard layout. I liked how Borsanova placed the controls (coil cuts on tone pots, phase and series on the volume pots), if it can't be done like this, it's not a big deal. As long as all the effects are there and if in the end it's 50's wiring, that would be great.
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Post by ChristoMephisto on Apr 17, 2010 1:45:33 GMT -5
I tried the 50's style wiring, 2x500k, and found the tone knob really brought the volume down too much too fast. Went straight back the soldering iron to restore it. Wonder if using a 1 meg tone pot would help
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Raz59
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Post by Raz59 on Apr 17, 2010 6:00:58 GMT -5
It's a trade-off really. Modern wiring - you lose highs when rolling off the volume knobs; 50's wiring - you lose volume when rolling off the tone knobs.
Although there is the option of installing a treble bleed or a buffer to fix these issues, I've heard that these options change the taper of the potentiometers and there is a compromise in tone...
Why would a 1 Mega tone pot help?
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Post by JohnH on Apr 17, 2010 7:49:14 GMT -5
It's a trade-off really. Modern wiring - you lose highs when rolling off the volume knobs; 50's wiring - you lose volume when rolling off the tone knobs. Although there is the option of installing a treble bleed or a buffer to fix these issues, I've heard that these options change the taper of the potentiometers and there is a compromise in tone... Why would a 1 Mega tone pot help? Particularly if you want the independent volume controls in series mode, I strongly recomend the treble bleed circuits, with modern wiring. Otherwise you will lose tone. Ive tried this several ways and this is the best. It does change the pot taper, and improves a standard audio pot making it not fall off so quick as you reduce volume - actualy its an ideal taper. But you can try it each way, the core wiring is not changed and it is easy to make changes through the rear cavity of an LP John
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Raz59
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Post by Raz59 on Apr 17, 2010 8:10:07 GMT -5
Speaking of independent volume controls:
When both humbuckers are connected in parallel, the toggleswitch is in the middle position and the wiring is stock, while the volume controls do allow for individual control of the humbuckers, if one of the volume pots is set to 0, both pickups are silent.
So while these are individual controls, they are not entirely "independent". A question now arises from me: following Borsanova's diagram, when both pickups are connected in series, are the volume controls wired truly independent, like I tried to describe, or not?
And John, if the treble bleed mod does indeed improve the standard audio taper pot, then I will have to scavenge for some 200k resistors...
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Post by JohnH on Apr 17, 2010 8:33:11 GMT -5
Speaking of independent volume controls: When both humbuckers are connected in parallel, the toggleswitch is in the middle position and the wiring is stock, while the volume controls do allow for individual control of the humbuckers, if one of the volume pots is set to 0, both pickups are silent. So while these are individual controls, they are not entirely "independent". A question now arises from me: following Borsanova's diagram, when both pickups are connected in series, are the volume controls wired truly independent, like I tried to describe, or not? Yes - In what im thinking of, in series mode, they are truely independent volume and tone, eg, you could have say, full or maybe slightly less than max bridge, and neck fully off, then smoothly add any amount of neck from 0 to 10, with or without the tone reduced from the neck, keeping the full tone, or not on the bridge. It works! The last vesrion that I built with these features was this: guitarnuts2.proboards.com/index.cgi?board=schem&action=display&thread=4571different wiring and controls, but same principles in series mode. John John
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Raz59
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Post by Raz59 on Apr 17, 2010 9:20:13 GMT -5
That last version seems to be a low budget one, but it is the kind of thing that I shy away from...you're using a total of 5 capacitors in the whole circuitry!
Now returning to Borsanova's diagram - if the volume pots are truly independent in both parallel and series, I might have a problem with that. While independent controls are extremely convenient, I read in a guitar forum that wiring it like that also poses as a compromise in tone.
But this is merely speculation and simple worries from my part. The important thing is getting the right diagrams!
John, have you figured out how to draw the schematic or should I take a humble shot at making some connections?
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Post by JohnH on Apr 17, 2010 18:12:32 GMT -5
I design my circuits to get the best combination of sounds, construction and operation, depending on what Im setting out to do and who it is for. They are sometimes complex, or sometimes simple but they are not 'low budget'. Also these diagrams take much work, I hope you can appreciate that. You are requesting help with one of the more complex designs that we have had here. The first step is to untangle the wiring diagram to make a schematic. This may not appear to be very helpful so far, but it is an essential step, and drawing/understanding these is the best way to understand the circuit. It shows the connectivty, in a way that is not constrained by the physical layout of the parts. So this is where it is at: The wiring diagram that you need is the next stage. The volume controls will work as normal in parallel mode, ie you can make mixes, but turning one down to zero shuts off all, but are fully independent in series. This leads to the need for the treble bleed circuits (which otherwise are more optional), and also, does not work well with 50s wiring. But what Ive laid out on the diagram will work well. Other than the issues i mentioned before, the other issue I picked up in doing the schematic (which was not on the original) is so that when you select single coils, the combinatins will be humcancelling, in series and parallel, in or out of phase. The single coil option at the bridge will be teh adjustable (screw)coil, while at the neck it will be the slug coil (or screw coil if phase-reverse is engaged). Hows that?, what sort of pickups ar you using? open or covered? And generally, is this all sounding like what you want? John
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Raz59
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Post by Raz59 on Apr 17, 2010 19:47:01 GMT -5
By saying 'low budget', I meant not having to buy four DPDT potentiometers, the diagram you posted previously only needed 2 slide switches, so it seemed like a low budget solution. I certainly didn't mean to degrade the work that is done in these wirings.
I myself am studying electronics engineering and circuit analysis isn't simple! Please don't make me calculate voltages/currents/resistances in that schematic =(
My guitar has a wax potted and covered neck pickup and the other one is wild and loose (unpotted and uncovered!).
John, I trust that you know what is more tonally advantageous in these complex wires. S4 maintains the parallel humbucker sound, right?
So the treble bleeds are needed because of how the circuit gets when both pups are connected in series? What's the compromise if they aren't installed?
I'm sorry for not being knowledgeable about this to give you a good discussion. Did you manage to implement 50's wiring when in "System Parallel"?
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Post by JohnH on Apr 17, 2010 20:36:18 GMT -5
By saying 'low budget', I meant not having to buy four DPDT potentiometers, the diagram you posted previously only needed 2 slide switches, so it seemed like a low budget solution. I certainly didn't mean to degrade the work that is done in these wirings. Ok no problem! Good luck with that! I did about a year of it, then changed to structural engineering (long time ago). If you did want to analyse these circuits, you might like this spreadsheet, described here: Guitarfreak - frequency response calculator See if you can make head or tail of it. And a specific version for 50s wiring is this: people.smartchat.net.au/~l_jhewitt/circuits/GuitarFreak_2_1.xlsJust click on the two tone control circuits to move between modern and 50s, with treble bleed as well. It doesn't do the series wiring. I found on my covered neck pup, that the screw coil sounds better as a single than the covered slug coil, whereas with open pups, it makes less difference. So Ill suggest that, to respond to that while still having best hum cancelling, we change to use the screw neck coil and slug bridge coil as the main single coil options?
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Raz59
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Post by Raz59 on Apr 17, 2010 21:09:06 GMT -5
That frequency response calculator seems like a powerful tool for analysis...I'll certainly save it for future use but right now I can't make any sense of it.
Since the wiring allows me to choose either of the two bridge coils with the phase switch, it is not that important which coil is the main one on the bridge. As far as the neck goes, the screw coil as the main one sounds like a great idea and I would prefer it that way!
That series mode is turning out to be an issue...I do see the benefits of the treble bleed, given the signal path... but I'm still reluctant on using it due to effects the 200k resistors have on the taper of the volume pots. By effects, I mean that the 200k resistors will make the volume pots sound the same from 2 to 5.
I'm contemplating sacrificing the independent controls in series mode altogether and going with a Master volume control when in series...50's wiring, for me, has priority over the independent controls but I don't know if you're willing to change the schematic
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Post by JohnH on Apr 17, 2010 21:24:11 GMT -5
The reason I did just a quick sketched schematic was in case it lead to a change. I wouldnt recommend launching into a big complex scheme like this until you are happy with what you are getting, nor to do a lot of wark to draw it up either.
The treble bleed, with the 220k resistors, changes the upper part of the taper, ie from 10 to 7 it falls less quickly, but it still is much the same from 0 to 5. IMO, Its a good change on a standard audio pot. How about this? since I have a guitar with this feature that will match what we are talking about here, Ill make a sound clip of a strum at each increment from 10 to 0, then you can judge tone and volume for your self? With luck I can do this later today.
Also, you might consider to do some test wiring, 50s v modern, just with a simple standard scheme, and get your own views instead of relying on forum stories? you would learn alot and it is easy to do on an LP John
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Raz59
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Post by Raz59 on Apr 17, 2010 21:39:29 GMT -5
My LP is currently wired 50's style with one of the pickups having the hot and ground switched so in the middle position I get the out-of-phase sound.
Before that, it was wired in a modern fashion. And there is no need to record clips, that would be too much work! I'll take your word on it and put faith on the treble bleeds then.
But with it them installed, it defeats the purpose of 50's wiring, right? This whole mindset about this style of wiring is purely about remaining traditional and aiming for an 'older' fashioned sound. The series mode with independent controls in this case is the antagonist to the old wiring...I'll just have to settle with modern then.
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Raz59
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Post by Raz59 on Apr 19, 2010 17:42:57 GMT -5
bump to the apparent end of the project!
So a summary of what's been done, for future reference: I requested a redesigned Twenty Dual Mix that included 50's wiring so as to have an old fashioned vibe.
In the particular case of this wiring, we have independent volume controls in series mode, so a treble bleed is needed on both controls; this in turn invalidates the whole point of 50's wiring (because it alone preserves the highs...having two things doing the same job is redundant).
So it will stay "modern" wired because of the reasons stated above. The treble bleeds can be considered beneficial as they seem to "correct" the upper part of the taper on audio-tapered potentiometers too.
Now, all that's left is drawing the actual easy-to-read soldering diagram based off JohnH's newly developed schematic. Anyone want to jump in and help?
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Post by JohnH on Apr 19, 2010 20:20:11 GMT -5
Hi Raz - Thats a good summary of where we are. I think that this is heading towards a kick-butt guitar, and Im happy to contribute to it. The addition of the bridge parallel option is nice, I have that on one guitar and its a good one. Ill be happy to do a diagram, if you can wait for it until next weekend, unless someone else feels inspired to do it sooner.
Based on your covered neck and open bridge, I did want to suggest swapping the slug and scre coils around on each pup, relative to that schematic to keep optimum humcancelling while giving you the neck screw coil as the main neck single option.
John
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