HBD: a HH (or HSS) Daemon MoBucker Jun 10, 2007 15:29:21 GMT -5
Post by Runewalker on Jun 10, 2007 15:29:21 GMT -5
The HBD, a Daemon of[/b][/i][/right][/size]
a Mother Humbucker
Building an HH or HSS Uberguitar
Beyond Tone Monsters, and into the
Realms of Mythic Creatures of Tone
a Mother Humbucker
Building an HH or HSS Uberguitar
Beyond Tone Monsters, and into the
Realms of Mythic Creatures of Tone
If you can’t stand my indulgent prose (and who could blame you) then just skip down to the Functions Map, Schematics, Wiring Diagrams and activity descriptions for the stuff that matters.
The genesis of this design came from my collecting a number of HH bodies with a 3 way pickup selector (Neck, Both, Bridge), a Master Volume, and a Master Tone. I affectionately term these “3-holers”, and for you who are old enough to remember, or with a breadth of reading experience, this term has a double meaning. This configuration may be the PRS legacy since his McCarty and other models had it, and the PRS mystique spawned a plethora of imitators. Subsequently there was an abundance of cheap “chassis” with this modern configuration that I could pick up inexpensively to pursue my disturbed modification experiments. Many had set-necks, which for me was a plus.
However, having grown up on Gibson Les Pauls and attenuating tone in the combo position by using the volume controls of the individual humbuckers, the Master Volume array was inexcusably unsatisfactory --- that and the paucity of unleashed combo tones inherent in a locked 2 HH, Local-Series-in-Parallel array, was a offending affront to the Tone Gods (or God if you are a monotheist). The Master Tone was less flexible than individual tones, but not as big a compromise as the Master Volume.
So these 3-holers (MVol, MTone, 3-way) seemed both particularly limited in capabilities and plentiful on EBay, even in set neck versions. For these chassis I sought design objectives that:
- Gave the critical volume mixing function between the Neck and Bridge in the combo positions.
- Facilitated true independence on the volume controls.
- Enabled the 4 main options in a humbucker: Local Series (default), Local Parallel, North coil, and South coil (Local Series OoP was a toss away for me).
- Gave both inner coil and outer coil combinations in single coil modes.
- Had not only these single coil selections, but single coil combos that maximized humcancelling options.
- Provided some OoP options, especially humcancelling OoP
Had a System Series / System Parallel option, irrespective of the Local array.
- Was as intuitive as possible and easy to move between critical presets for live play.
- Provided a layout and physical switch settings that conveyed visual and tactile feedback as to which options were engaged.
- Had no dead settings
- Optimizes settings so that every option is distinct, musical and a keeper.
To whom I owe ……
With the scope of this project I knew I needed help (electronic, not just mental). Naturally I sought assistance from the Down-Under, MasterBlaster, and the inimitable Mr. Led Hewitt. Certainly because of his brilliance, but especially for his patience in working with those who won’t learn the background electronics to be able to finish the designs (yours truly). I can dream this stuff up, but can’t produce the electronic engineering. JH can do both, and is one of those sick individuals who enjoys these challenges (Cheers JH). This was a months long, start and stop endeavor. I believe JH also brought in the our own inimitable Unk.
Sidebar: After JH designed his JHJP (Schematics Page) an enhanced and possibly penultimate Jimmy Page mod, I whined that I liked it but wanted the inner/outer combos. He frowned and pointed me back to the HBD we had worked out, and said I already had it, assuming my willingness to drill only 2 additional holes in a Gibby array. The light bulb popped on. I had been so focused on the 3-hole physical limitation that I failed to recognize that I had, what for me, was my reference SG/LP design, right in hand. So while the design was originally developed for 3-holers, this is now my preferred installation is all of my Gibby Style, 4 pots and a 3-way. The exception is of course instruments with appreciating value potential, like my ’68 Les Paul, which will remain stock. To finally take this out of the design lab to the testing bench, a Gibby style SG clone (bolt-on) was selected as the mule for the prototype (a 5-holer converted to a 7-holer with the two minis).
What does the “HBD” acronym mean?
The original design was intended for a guitar that conveyed a visual image that was funny to us in the development stage. However, while bandying the term around among friends was fine who understood the real meaning and were not deflected by how it sounded, it was unsuitable for public consumption …. It would be misinterpreted as being politically incorrect in our “sensitive” age. Oh no, we could not have that. The creators are stuck with the acronym since it connotes too much history in working out all the details and thinking through options.
So like the poet that does not explain his poems, we leave it to the reader to provide their own interpretations of the acronym. Since there are so many humcancelling options here, some possible references with “HumBucker” for the H and B positions might include: HumBucker Deluxe, HumBucking Dervish, HumBucking Devil, HumBucking Dawg …. Daddy, Daemon, Dadist etc. None of those is the one, but knock yourself out …. or not.
Ok, enough history and intro, What the heck does it do?
Schematics and Diagrams
JH: If you skipped down to here, to recapitulate, this design works well in Gibson SG/LP style guitars, with two volumes, two tone controls and one Switchcraft style 3-way. That chassis will require drilling 2 quarter inch diameter holes for the mini toggles, so it will not keep a “stock” appearance. It was originally designed to modify a modern HH with one 3-way and two potentiometer holes.
As always, if you can do it with a HH you can do it with a Fat-Strat., as long as the mid or neck is RWRP. You could even keep the standard Strat pickguard by substituting a Tele style 3 way in the slot for the lever switch. But I think if it was me I would get a new pickguard with no slot and put in a Switchcraft 3-way just to annoy and throw people off.
Focusing on the SG/LP style configuration, the volume and tone pots have push/pull switches. In addition there are two 4-pole mini toggles:
- The toggles (S2 and S4), one for each pup, are mode switches for the dual-coil humbuckers, whereby the “pilot” selects ‘2-coil’ or ‘1-coil’ operations for either the neck or bridge pickup.
- In 2-coil mode, the push/pulls on the tone pots (S1 and S3) select local series (in) or local parallel (out).
- In 1-coil mode, S1 and S3 select inner coils or outer coils. There’s no phase switch, but when single outer coils are selected, they are phase reversed.
S5 is a normal 3-way toggle and S6 is the system series/parallel switch, which bypasses S5 when activated by pulling the neck volume p/p switch.
In combinations of single coils, hum-canceling is automatically optimized by:
- either selecting a north and a south coil in the same phase, or
- two of opposite polarity but one reverse phased.
Hence, both inner or both outer coils are in the same phase and are hum-canceling.
Picking one inner and one outer coil however, delivers a combo that sounds out-of phase and is also hum canceling. Having the outer coils reverse phased and the inner coils normal phase also provides a variety of options when both coils of one pup and two of the other pup are selected.
RW: This may be easier to “see” in the Functions Map below, but will take a little study to fully reflect on the vast array of options available. While this may be a matter of opinion, there are no “trash” options and no switching choices that are dead. Certainly some will be favorites, but every one of them is musical and usable.
JH: The volume controls are ‘forwards wired’, ie, in normal parallel mode, they are like most stock LP/SGs. Treble bleed capacitors and resistors maintain the tone at lower volume, to compensate for capacitance of the guitar cord. An implication of forwards wiring is the interaction where in parallel combos, one volume can cut out both pups. Its not a big problem in practice because the mixes that we want are all at volume settings way above where this interaction occurs. But this design, when adapted to use an on-board buffer (see below), can be amended to add extra resistors to separate the pups and avoid this interaction. In series mode, the volume and tone controls are fully independent and act only on the sound from their respective pups.
RW: In playing this turns out not to really be an issue. In SysSeries, where you would want more VolControl independence, you have it. In SysPara, rarely would you turn one pup all the way off anyway -- You would just flip a switch if you wanted to get away from a pup. The blend effect is more pronounced in SysSeries.
JH: The drawings here are with passive wiring as built so far, but it also works very well with either an on-board buffer or a buffer cord. We include the original HBD with a buffer circuit just to show it, but in that case you would want determine whether you want to include the tone bleeder components.
RW: There are 4 main “ah ha” points of the genius in John’s electronic design driving this project:
- The function of the minis is intuitive and simple. Up for 2 coils and down for 1 coil. While the thing is a bear to wire (tiny little lugs, lottsa wires) in operations is it just so simple to grasp.
- The dual functions of the Tone Push Pulls: In 2 coil mode, they determine Local Series or Parallel. In 1 coil mode they determine Inner or Outer coil activation
- The visual cues the positions of the switches tells you what you have engaged
- When one PP is up and the other down, and at least one primary pup is in single coil mode, you have various out of phase positions.
Multiplexed functions out of the same switch reduce the apparent number of switches and because of the operational logic, give ready visual feedback on your choices.
John Hewitt Electronic Schematic
HBD Gibson SG/LP Style - Wiring Diagram, with Tone Bleed Components
This keeps a nearly stock appearance with the exception of the 2 unubtrusive mini toggles. A true wolf in sheep's clothing here.
HBD Original Wiring Diagram (3-Holer) with Buffer Shown
If you have very hot pickups, like this test unit, then a buffer circuit or buffer cable really helps clarify the tones. It is especially useful in clean settings, conveying a separation and crystalline shimmer to the output in the single coil, local parallel and OoP modes. This clarity, however, also forces you to play better because every mistake is also clear. So be forewarned.
In the refinement phase of the design, we are experimenting with the unused Bridge PP to either add a cord capacitance emulating capacitor, or an on-off switch for the buffer. To my ears, the buffer is a little too brittle when it comes to hard overdrive power chords and lead work – suffering the same issue as trying to play metal with a Strat --- it’s just wrong. In that situation you can dial in quite a bit of tone pot but it still is not the same as a no holds barred, crank it up and burn, normal guitar-to-cord-to-amp sound.
This is the most versatile range of settings in an HH guitar I have ever had. This turned an SG style guitar from a 2 or 3 trick pony in Gibby configuration, into a vast surfeit of sonic options covering Teles, Strats, Ibanez/ESP/Jackson Shredders, traditional Gibsons (solid bodies and jazz boxes), and other nether world instruments not invented and unexplored by humans.
It has, of course, the traditional Gibby settings of Local Series pups alone or combined in System Parallel (yawn) so no convention is ignored.
Key tones beyond the limited Gibson choices include:
- Local Parallel settings: Completely quite, near single coil shimmer, especially with a buffer.
- Neck Local Parallel with Bridge Local Series Fills out the restrained string amplitude heard with just a bridge Local Series humbucker. Like adding a PAF (in this guitar) at the neck.
- Neck single options with Bridge Local Series. Similar to the N-Local Para, but a slight bit more power from the single coil neck. In clean setting, subtle difference between the N and S neck coils. Can’t hear the differences in overdriven modes.
- Inner/Inner, System Series or Parallel. This gets more in the direction of the Neck/Mid 4th position Strat sound in System Parallel. Mild to no hollow quack in this particular guitar but nice shimmer. It is like the 4th position has been smoothed. I think in a 24 fret chassis you could even get quacky, which might get you arrested if you did so in public
In System Series it is like having a 3 humbucker Les Paul and shoving the mid humbucker in the circuit. Humcancelling of course. Very cool.
- Outer/Outer, System Series or Parallel. More Tele-mid-position like - treble definition but still nice and full. Kind of a beefy-meets-piercing in System Series. Very usable. Humcancelling to boot.
- Bridge Local Series, in System Series with Neck Single-coil Outer (reverse phase) and in amp at medium overdrive. OMG, Houses of the Holy. Keep Jimmy P away from the dealer.
- System Series. Neck Single Mode, Neck Tone PP up for Local Parallel, both volumes way down around 2-4. Setting is reverse phased. Quack Master. With the Bridge in low output local parallel, the outer Neck cut coil position OoP, and the volumes way down, the hollowness kicks in. Must be shielded well as this is partially hum-canceling.
- Home base. System Series. Volume on both at home around 3-4 or 4-5. Neck and Bridge in Local Series to start. Here is where you can stay all night. More treble, then adjust the volume mix, or kick in the Neck single or local parallel, adjust the mix. Or kick in System Parallel for more clarity. More beef for a searing lead, hit the overdrive foot switch, roll up the Local Series Bridge and burn, adding base with more volume on the Local Series Neck, or more treble with cut-coil neck or Local Parallel neck. Get quacky with the OoP version. Most key go-to tones are one movement or a mix adjustment at the volumes.
Here you control tone by the mix and the add-ins or take-aways. Of course there are always the tone controls, what ever the heck those are
Referring back to John’s previous tech description:
Picking one inner and one outer coil delivers a combo that sounds out-of phase and is also hum canceling.
These are useful, musical tones that emulate many Fender tones, yet are smoother than OoP settings I have heard in other installations. This is where quack can start happening.
Having the outer coils reverse phased and the inner coils normal phase also provides lots of options when both coils of one pup and two of the other pup are selected. This last feature produces sounds more in the Jimmy Page OoP tonal spectrum. The OoP is the more ragged type I typically associate with OoP, and pushed with your amp can peel the potatoes should you care to.
Hot or Vintage, “Authentic Strat sounding singles…” and “to quack or not to quack, that is the question.
For HHs that employ the cut coil options, I prefer modern, higher output humbuckers, opposed to the PAF and other “vintage” styles. It is just a personal preference, with inherent compromises, as any design decision is. With respect to the cut-coil part of the design the rational for higher output pups is threefold:
- I tend to prefer a beefier single coil in the direction of a P90 than the thinner sounding (to my ears) Strat style coil. While the P90s sound is influences by the breadth of its coil and the double magnet structure (oppose to a smaller profile, magnetic poles structure of a Strat), they were out of the box higher in DC resistance. And not to get into “higher DC resistance does not necessarily mean more powerful” argument, almost all agree they are a beefier, fuller sounding single coil. Higher output humbuckers have higher output individual coils, which in single coil mode tend to take some of the edginess off the Strat style sound. That combined with the unavoidable interaction with the inactive adjacent coil, give it single coil sound, but not usually a “strat sound”, which is also affected by other things than a stand alone single coil.
This, the longest bullet point in the world translates to: I want a higher output single coil, so I choose I higher output humbucker to split.
- I was a reluctant convert to John’s buffer, but now that I have lived with it I know it gives a clarity and sparkle to clean tones heretofore unachieved. With the buffer, much of the muddiness associated with high output humbuckers, especially in the neck position, is mitigated. And the buffer makes the volume pot much more functional, dispensing with muddiness as the volume is turned down. With then the buffer and a vibrant volume control, turning down the hot pickups renders it into vintage style territory
- The local parallel options were important to me, although you will hear many cast aspersions on them. With hotter pups the local parallel goes into vintage PAF territory. For example this neck pup comes in at local series of 16.5K, its single coil reading is 8.23K and its local parallel reading is 4.1K. Very nice step downs (or up). The Bridge is slightly hotter. A resident tone is setting the neck to the vintage sounding local Parallel, the bridge to hot Bridge local series, then controlling treble or base with the volume mix and the heat or clarity with the System Series switch. If you were just wanting to play and not think so much about switching, you could stay there all night.
So does it sound like a strat in cut-coil mode?
The only reason to bring this question out, is that I have come accross a lot of discussion about cut=coil humbuckers not sounding like strat single coils. There are many reasons Strats sound like Strats, beyond their pups.
Like other cut-coil guitars, this one does not sound like a strat in Neck or the bridge, inner or outer Cut-coil mode. There is a clear single coil sound, but not necessarily reminiscent of a Strat. It is probably closer to a Tele sound. If you read the Sonic Evaluation, there is one setting that sort of gets you to the Strat 4th position, but it was not intuitive that it would -- an OoP, with a Local Para and a cutcoil.
Other cut-coil humbuckers I have had go more in the strat direction. I have one that is less “hot” than this one that gets closer, but still is different. Seymour Duncan and Dimarzio both have pups they claim sound strat-like in cut-coil mode. I have not experimented with them to validate or dispute the claim.
For me it is a non issue, as there are so many Strat clone sounding guitarists out there, it is almost a disincentive to sound like everything else. Plus, if I really want that, heck just go to the rack and pick up a Strat,or install this in a Fat Strat type. As noted previously, the Strats physical construction also contributes to that sound.
Winding this post up (Thank the gods...)
This design is for me what I have been searching for since I started this journey towards wiring and tone nirvana. I suspect this will be my standard mod or install if building for myself or a musician friend or two.
A background agenda was to make one guitar as versatile as possible but one you did not need an aeronautics engineering degree to drive. I have a good friend who plays live a great deal. Two summer ago I went to one of his sets and saw him change guitars 7 times as different tunes called for Strat tones, or Les Paul tones, or, God forbid, acoustic tones. No, he did not have 7 guitars, but the switches were between 3 different guitars. Swapping guitars that many times during a set would be fine if you were supported with your own tech and roadie. He, alone with many “keep the day job” musicians doesn’t have that luxury. So I placed in mind the objective to eventually find an uberguitar he could keep throughout the set, with maybe one backup. With the buffer this guitar could even credibly cover acoustic rhythm tones, and help you grow the hair back on you legs after playing acoustic so many years.
This is that guitar. An uberguitar for the people who play because they love it, not because they can afford it.
It does help to understand basic ideas on what system series or parallel, or cut-coils or local series and parallel do to the sound, so you know where you are driving. But even if you did not, you could learn the settings by listening.
The design is finished as far as I am concerned. But I welcome feedback and will try to steel myself for the onslaught. Also, I'm going back into the mule for some cap tests, etc, and a little luthier work, so I'll try to post a pix or two of the physical wiring. As an aside this is a fairly labor intensive wire up, but very logical with the Bridge and Neck modules being nearly clones of each other.
EDIT by John H 3 December 2010:
Another HDB has been successfully built by Fenderbender - see this link for discussion: