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Post by roadtonever on Feb 4, 2011 18:11:08 GMT -5
The Jerry Donahue wiring was up for discussion on an other forum and I asked about the function of the 6.2k resistors in position #4. I believe it has been correctly condenced as this: www.tdpri.com/forum/just-pickups/56662-what-jerry-donahue-schematic.html#post566873Someone chimed in explaining it has to do with de-coupling two pickups connected in parallel and reducing the inductive loading between them. Well the diagrams and litterature clearly indicate a series connection.... Regardless the explaination was given by a person for who I wouldn't have reason for disbelief and as I often feel the sound of two pickups in parallel leaves an overly accented resonant peak I felt intrigued and decided to gave "de-coupled parallel" a whirl. I followed the diagram above excluding the resistor and reversing the neck pickup leads. Naturally it was mud city, annyone who has added a small value resistor in series with a pickup before will know this. I then tried it backwords, or more accurately mindlessly trying to add the resistors a different way without taking notes  Still sounded like mud... I get the feeling I'm applying the idea wrong. Looking forward to hear what the knowledgable folks here make of this. (BTW What is the function of the resistors in the JD wiring?) |
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Post by newey on Feb 4, 2011 19:40:07 GMT -5
The link in the TDPRI thread goes to another TDPRI thread, where a wiring diagram for a Peavey Omniac Diagram is posted. This guitar, according to the poster, does essentially the same things as the JD Tele (just not in the same order). Note that the Peavey uses a Superswitch to achieve this, and I suspect the JD does so as well. GuitarMole at TDPRI indicated that he thought the resistors and cap were because: He's right, I don't think it has anything to do with the parallel connection. This is essentially the "half out-of-phase" mod we have extensively discussed. The 2 pickups are wired OOP, but the cap changes the waveform of one pickup enough that the cancellation isn't so dramatic. I don't know what literature you're referring to. The diagram shows a parallel connection. The Fender description calls the position 3 sound a "classic Tele" 2-pickup sound, which would be parallel. Here's some of our discussion on the Half Out-Of-Phase idea. Since the same value resistor is used on both pickups, I can't see where it would affect the half-out-of-phase thing. I don't know what they're doing in there. |
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Post by 4real on Feb 5, 2011 5:04:04 GMT -5
Hi...
I looked into this and read on it somewhere years ago...of course the most authentic way to get that strat type sound is to...besides play a strat...put a middle pickup in a tele...I'm even considering doing that to mine...however...
I did the half out of phase mode the other day as well...so can speak to that and this diagram as my new strat has some similar options in it...
Well, that diagram didn't translate well...but it makes a bit of sense and can see the intention.
Basically they are wired in series and out of phase...the phase moderated by the cap and I think the resistors there to bring the level down to about the level of your parallel 2 pickup sound.
Normally OoP will give you an extremely bright "phased" sound in parallel and in series. Series tends to be louder and darker as a rule and the phasing in either mode a little extreme perhaps (my tele has a phase switch and I know Albert lee is a fan of straight parallel OoP on his teles).
So...after trying a lot of caps, that )1uF did seem to produce the best results for me as well...and this is the value in the mod here as well...so others have like it. This significantly tones done the extreme phasing effect, and in paralell then is louder. I suspect that the resistors are to keep the series thing at a similar relative volume to the other parallel settings while giving a milder OoP sound.
...
If considering the mod, you might consider using some little trim pots in the control cavity and adjusting to taste and your pickups...a pair of 10K trims should do the job and easy enough to source.
You will get a bit of a hollowed out sound..how close it is to a real strat is for you to decide I guess. Should be a noise canceling position to which is a bonus.
You will probably need a super switch though...could be tricky fitting it in your average tele...they are a little deeper and a lot wider than a normal blade switch and those cavities are small.
There have been many attempts to get this kind of sound, usually using little transformers and such...but this should get you in the ballpark or at least give a serviceable sound.
BTW...even though in a strat the pups are in phase, the relative location of the pickup along the vibrating string makes them "physically" out of phase and gives it that characteristic sound. If this mod was only in parallel, it would cut frequencies, but since this is series, it is already louder and moderating the phase takes out the extent of the phase cut as well.
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Post by newey on Feb 5, 2011 9:21:01 GMT -5
No, they're not in series. The stylized schematic is a bit hard to read but clearly shows neck + and Br - both wired to ground, and Neck - and Br + both go to the vol control at the other end. So, it's parallel OOP (w/ the cap and resistors). The schematic posted is just showing the state of things at position 4 on the 5-way superswitch. Check the Peavey diagram I linked to, it's essentially the same wiring at position 3 as the Fender description of position 4 on the JD Tele. EDIT: Found this, from one of the TDPRI guys. This may facilitate the discussion:  Note that the Peavey Omniac JD doesn't seem to decouple the tone control at the neck position as the Fender one does. |
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Post by roadtonever on Feb 5, 2011 11:36:23 GMT -5
Still have some electronics 101 to study, I see I misstook reverse phase for series... I'm sure one of the older JD signature guitars we're series OOP tho.
Anyway the explaination I recieved on the other forum gave me an image of a subtle effect on a two pickups in parallel sound making it more natural. I know that adding resistors in series as well as parallel lowers the height of the resonant peak just like a 500k pots vs a 250k pot with the series resistor having stronger effect from a larger value resistor, opposite to a parallel added resistor. I guess the 'decoupling' is nothing more than a side-effect and not meant to be a subtle one, right? I mean there is not a third way of adding resistors is there?
I sure liked the sound of "regular" OOP with series cap on guitar that will be trying it out on bass. I definitlevly see why you'd add a large amount of series resistance the JD way, it's quite bright!
One intruguing fact I see here is that the values of the resistors are very close to the DC resistance of typical strat pickups.
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Post by 4real on Feb 5, 2011 16:20:53 GMT -5
OoPs...I mean ooops It even said ground on it...LOL One thing that occurs to me is how easy it would be then to simply add some resistors and a cap for a $1 to the centre position on a tele and see how it sounds  Being OoP automatically gives you a bit of that pos 2-4 quack in a way. Using the cap tones this down from being too thin and "scratchy". I have a straight OoP switch on my custom tele (FWR pup in the bridge and SCn tele neck pup)...as the pups are wider apart than the N/M or B/M the OoP thing isn't as bad as with pups closer together it seems...it's a usable sound and has some of that hollow quality, but it is a bit 'extreme' The guitar is here... guitarnuts2.proboards.com/index.cgi?board=music&action=display&thread=5318There is a sound clip here "Bluetelful1 (part1)", the OoP playing is at 3:00... www.soundclick.com/bands/default.cfm?bandID=869409It would appear that the Fender JD has already a strat Pup in the neck position it seems... The .01 cap is wired exactly as per the "half phase" idea. So...it would reduce the extremes of the OoP effect as heard on my tele...fuller and louder than straight OoP. ... Interestingly, I can simulate this on my new strat to a degree and switch back between half OoP and in phase...not quite the same, but able to compare parameters like: 1/2 OoP or not, series or parallel, loading with the vol control, etc...with the bridge and neck Pups....and comparing this with a real B+M and identical pup type in N and M. It does indeed sound very much like the "notched" strat sound of position 4 of a/this strat (B+M)...when N+B 1/2 OoP with the Bridge HB split.
Comparing it to the real M+B (not OoP) which I can switch to instantly...it is almost identical...there is a slight high end spike to the OoP N+B version.
It is pretty much the same volume as well as the N+B not out of phase...this sound is similar to that of a N+B tele, bold with a slight quack.
The 'series version' is a darker, more "chewy version" when OoP and considerably quieter...much more "phase-y" as opposed to "quacky"... Interestingly, this also ties in with my "Spin Select" control for my bridge HB...the latest Version 3 added a variable resistor (up to 250K) and a .01 cap into the mix on one selection. It's not OoP but does change the character of the pups resonance when engaged and adjusted. Perhaps the additional resistors in the JD scheme helps take off a bit of that "high end" subtle difference between the 1/2 OoP N+B and a real M+B sound. Playing around with the two N+B 1/2 OoP vs M+B some more...sorry I can't post an audio at this time...the N+B OoP is a little louder and "bold" while the M+B is "airier" or "soft"...more authentic "Knophler; Sultans of swing solo sound" but both equally convincing at it... In fact, it would be extremely difficult to tell the difference on a blind test and few would be able to tell in a mix...neither are "better" than the other, even if the M+B is a little more "authentic". Especially on chords, the OoP version isn't as "light" as the real thing, but turning down the volume control (with out treble bleed, so adding resistance and loading) just a touch gets it even closer...so I imagine that's what those resistors are for...but that "notched strat tone character" is pretty close regardless. ... After this mornings tests I am seriously thinking of doing the half phase mod on my tele to get this sound in place of the straight phase thing now! I had been toying around with adding a middle pup to get this sound (wired in place of the tone control to fade in to any position) but this would be a lot better (no cutting up my guitar which is the only reason I've been put off)...so thanks a lot for bring this up. If I do, it may be sufficient as is with the 1/2 OoP mod...but one could easily add a resistor into this mod on the dpdt phase switch I suspect (on my guitar in a push/pull on the volume control). ... OH...I found this in a review of the Peavey Omniac JD... So, pretty much saying exactly what it is...the 1/2 OoP mod...even down to the suggested 0.01 cap!! Given that there is only 5 selections and two pups...you could get all these sounds pretty much I suspect by just doing the 1/2 OoP thing say in a push pull...and using the tone control to get that "woman tone" sound perhaps...easier than wiring up a whole super-switch I suspect. Otherwise, perhaps a series NxB would give you a thicker more gibson sound...maybe brought down in volume with a resistor and/or cap to taste. My strat gets a good "jazz" deep sound with all three Pups in series. The NxB is more of a bright HB sound...so perhaps switching in a cap would create a similar effect. Ah...NxB with the master tone down a fair way...very much that kind of "montgomery" jazz box kind of muffled tone...great for octaves in that style. ... Note though that both of these JD tele's have Strat Neck pups. I actually like the richer tones of a tele's traditional skinny neck pup and you should get fairly similar effects I believe. I recall reading a guitar player interview when all the Helecasters got signature guitars and that the JD strat had extensive subtle alterations...a few mils closer to the bridge and a metal plate inlaid under the pickguard to get a more tele bridge sound and an SD designed rotary switch to switch between tele and strat like controls. ... Anyway, interesting to have been able to compare the two (N+B 1/2 OoP and M+B) in the same guitar and note how similar the two are. The half OoP mod only went in last week and with 30+ combinations a lot are going to be similar...I hadn't noticed how close this one was. It would be a good addition to a tele and will try it out on mine at the first opportunity. The OoP sound is good, but it is extremely versitile, while this notched strat sound is a classic! EDIT: Found this as well, selector descriptions almost identical... guitarcollecting.co.uk/signature-guitars/fret-king-jerry-donahue-black-label-series-jd-guitar/Fretking JD signiture with "trev Wilkinson...how many sign models does this guy have!!! His MIJ Limited edition strat wiring seems to be far more elusive...might have to go through some old GP's... forum.japanaxe.com/phpBB3/viewtopic.php?f=6&t=989Here's one but the wiring had been altered, so no clues...interesting discussion about endorsement deals...those Helle guys must have a lot of guitars...I wonder if they have each others models to play around with gratis as well...LOL...do love their playing though! |
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Post by roadtonever on Feb 5, 2011 17:37:34 GMT -5
4real, I saw your reply in the HOoP module thread. Glad to see you posting here. Interesting to read your observations, and the track you recorded was truly sweet. I guess the JD wiring is a hell of an accomplishment, creating a third pickup out of a cap and maybe som resistors.  Being more of a Les Paul guy the strat middle connotations don't mean as much to me as it might for some people even if I reconize it when I hear it. What I do notice mosty is how it totally gives your mids a new character. In fact I spent most of the afternoon auditioning different cap values for HOoP in my bass. Initally reacting on how the honky yet equally scooped mids would work well in a metal situation quickly segued into busy neoclassical arepeggios and vamps and Bach excerpts which sounded perfect through HOoP. PS: I may be making a too big thing out of this reduced mutual inductave loading between two pickups via resistors thing. The idea that popped into my head of a sound in between two pickups in series and parallel is attractive but not necessarily based in reality, maybe rather extracted out-of-context from flowery explaination on a related matter. That's what having a flaky understanding of electronics yet being fammilar with wonders like OOP with a series cap creating a third pickup out of thin air does to you!  |
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Post by 4real on Feb 5, 2011 20:05:27 GMT -5
Cool RTN....
The post got me playing before my first cup of coffee this morning...playing with different sounds, came up with three new riffs/tunes in teh process...plus I can touch type...LOL!
Now...I really need a new computer and get this recording thing down...then I can do a lot of different samples of stuff perhaps.
A normal OoP sound is kind of specialized...it alters a lot between guitars and pups. The sound of a series and OoP start NxM or BxM is unusably weak on my strat.
On a bass, well, the values and such might need to be radically different.
Thanks on the tune...very late at night, first thing that came out of the guitar...mostly to demo the sustainer as well.
You can here how "jazzy" that SCN neck tele pickup can sound...surprising pickup for such a skinny little thing...great sound.
The OoP is very specialized. It worked ok for that funky 4 string chord harmony thing...but I'm strumming them pretty hard. It pops out of the mix and works, but I hardly ever use it at all playing it live, and that guitar has been my main axe for over two years.
If you look in the gallery you can see my new strat...it has an amazing array of interesting and usable sounds, over 30 without visible switches.
It's been really useful for things like this where you can put the neck pickup in reverse phase (now 1/2 OoP) and go from position 3 (N+B or NxB) and position 2 (M+B or M+B) with no phase instantly...and with both neck and middle pickups being identical...it's the perfect guitar to make this kind of comparison...so more than happy (and a little surprised by the results) to do the comparison.
Tele's are great though, if a little unforgiving. I particularly like the N+B thing they can do so my strat has that in position 3 with the MR scheme in it (it can't do middle alone) so has a bit of the 'tele' about it. I was playing a lot of soul type stuff, and it's a great guitar for that kind of thing.
I have two more cheap tele's to sell...but I might even mod them with this HOoP (I like that, easier to type!) thing on a mini switch...maybe even two to get a series mode perhaps...see if it ups the resale on commission.
...
Anyway...the plan, being sunday morning...will be to mod my tele later and see how the HOoP mod goes in that guitar.
The OP of the HOoP Mod thread I see put it into an LP...and so, thinking that it might be a really useful mod to the phase switch in that elaborate 22-Dual Jimmy Page like wiring as well.
It has a really interesting effect on the "broadbucker" kinds of things like my strats NxMxB setting...
...
Oh...and I forgot...there is a Bonus to the HOoP mod that hasn't been described!!!!
Pulling the phase switch would normally only effect the sound of pickups in combination...however, the HOoP Mod also effects the sound of the neck pickup on it's own when activated...so you are really getting two new sounds. It's kind of subtle and hard to describe...a bit kind of brighter perhaps, but not phase-y of course...I suspect that connecting the cap and possibly a resistor to a different phase switch connection...or several other simple mods you could make to it, could yield even more varied results....as would a different pickup.
If I can find some suitable parts, perhaps a trim pot...I might see what I can come up with on the tele...what would be cool would be to pull the HOoP switch and get both the phase effect with both pups, and a new say deeper jazz tone on the neck alone...anyone have any theoretical ideas on that?
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Post by 4real on Feb 5, 2011 23:58:54 GMT -5
Update...tried teh HOoP on my tele and...well, it wasn't that good  really just very similar to the usual 2xpup sound on my guitar. My tele already ahs a semi-quack in part to the Huge WR pu in the bridge. I tried a few different caps and even found some resistors...but the best effect was the normal phase as it was...so much as it is in that clip. I also took the time to fix the tone control, required a bigger pot to preserve the treble I like on this guitar...so a 1 meg volume and a 500k tone pot...I tired a few caps that I ahd around, found that an unusually small 0.001uF cap had the best resuts...extreme in total off, but generally a nice "wha" across the whole range. The effect on the strat is as described, so I can only assume it is the unusual pickups in the tele that prevented getting as good a results...so it is worth trying but be prepared to tinker or for the results to be not quite as good as one might hope. Remember all of JD's guitars have strat neck pups and this probably makes a bit of a difference. Shame, but you never know if you don't have a go do you. Was good to have the tele out again after a few months though. I even took out the LP to see if that might benefit from the HOoP Mod, but decided against it as the phase things sounds pretty good as is. Sounds exactly like the Doobies "listen to the music" rhythm style. |
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Post by roadtonever on Feb 6, 2011 17:46:58 GMT -5
I gotta learn to touch type my self some day...
Love the HOoP bonus also. It just sounds very guitar-ish. Used it a lot when I was part of folk-rock project with lots strumming, arpeggios and simple melodic lines.
The SCN pickup is designed by Bill Lawrence BTW.
This guy wrote back to me about the decoupling resistors:
Sound promising, I'll try this idea and see if it's still not too dark if wired direct to jack.
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Post by roadtonever on Feb 6, 2011 19:19:48 GMT -5
So I pulled out the alligator clips and resistors. I felt clever and chose resistor values based on DC resistance of my pickups (beofre this I looked up the DC resistance of pickup used in the JD signature Teles and noted the DCR's we're close to the values of the series resistors) and went direct to jack this time. Straight away it seemed differant than regular parallel and series. Mids have lots of texture! I'll have to go back tomorrow and A-B de-coupled parallel against regular parallel and series and see if the tone is really in-between. I'll focus on low end volume as well as spectral position of the resonant peak which should be reliable indicators of the de-coupled parallel working as advertized.
Speaking of the resonant peak in my case it's quite attenuated :/
Maybe it would work better with regular singles than hum-cancelling ones like I have, they're twice as high DC resistance as traditional singles.
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Post by 4real on Feb 7, 2011 0:24:51 GMT -5
That's an interesting point about singles...mine are fender noiseless on the strt and that works well...but I already have a middle LOL. On the tele some of the "problem' is that I have a big FWR in the bridge and this already gives some of that middle sound with the neck combined.
Albert Lee uses a straight OoP and works well enough on this guitar for special purposes...as you can hear from the sound clip. Good to have the tone control working though...so thanks for getting me to open her up! Shame it didn't quite have the effect I was hoping for...but perhaps I might try again after you do the hard work!
The resistors should load the pups much like turning down the volume a touch I guess...taking off some of that high end edge. The "notched strat" sound is kind of scooping out the midrange leaving that airy top end and some bass. I had a strat with three phase switches at one stage, interestingly, OoP the middle pickup created the opposite effect and made a nice midrange kind of sound.
I tried a couple of resistors as well, similar value to the JD...in fact I left one in the OoP switch, but it made little difference in mine.
I actually could open up the original FWR pup and 4 wire it, I've heard that it might be a bit tricky...and the thing is vintage and worth more than the entire guitar is seems...so might have to leave that...but splitting it to the inner coil I expect would make more of the mid pickup thing...but I'm back to the strat now so it's not really that important.
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Post by roadtonever on Feb 9, 2011 16:59:52 GMT -5
Well life got I the way and I haven't done any ABing. Tho' I plan to do so tomorrow!
Yet I wonder if I should make anything of the lack of responce to the idea of inline resistors preventing inductive loading between two pickups connected in parallel.
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Post by 4real on Feb 9, 2011 17:08:08 GMT -5
I've got to head off to town...
I ahd wondered abut this aspect of the thread...but am not sure what you mean by it...still dont't
In the meantime, while unsuccessfully looking for my 2008 tax assessment...I did find a paper copy of the torres enginering, cap, resistor, inductor thing that was supposed to produce something of this 'mid pickup effect' on a p-p tone control. When I get back I'll see if I can find the link about it...
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Post by newey on Feb 9, 2011 17:51:03 GMT -5
RTN- I think you're right about the resistor preventing inter-pickup inductive loading. Seems to me we had some discussion of that effect some time ago, I'll see what I can dig up. Or some other gai may know . . . Whether the effect is deleterious or desirable is going to be in the ear of the guitarist, it may not necessarily be bad . . . |
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Post by sumgai on Feb 10, 2011 2:45:41 GMT -5
.......
Or some other gai may know . . . One of those "other gaiz" might express himself thusly: extra resistors in the circuit - not good, bad for tone. Coincidentally, that's was just a few months ago, in the HSHSHS/SSSSSS thread. One probably should start there, for the reasoning behind John's statement. (Which, for sum strange reason, I happen to fully agree with.  ) But then again, who am I to pee in sumone's Cheerio's?  If it cranks your turner (as it obviously does for JD), than by all means, go for the gusto. After all, it's neither my money, nor my ears, that are on the line here, right? Oh, all right, I'll drop a clue.... let me paraphrase G. Santayana here - "Those who slept through the class on reactance and resonance are doomed to learn about them the hard way." That won't appear in any Wiki on the web, but you might google for those terms...... Just a thought, such as what passes for one these days. HTH sumgai |
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Post by roadtonever on Feb 10, 2011 19:05:41 GMT -5
Thanks guys. Doomed is the word. Nevertheless I just completed some testing. Recorded the same riff in parallel with inline resistors matching withing 10% the pickups DCR, regular parallel and regular series without any extra resistive load AKA straight-to-jack. These were my findings: Decoupled parallel didn't magically shift output and resonant peak in between series and parallel, in fact these characteristics were just like regular parallel. What it did seem to add was a livelyness and texture to the mids, different from the scooped-out regular parallel and smoothed-over series. Naturally it sounded like a tone knob turned down as well. I decided to try swapping the in-line resistor values to x0.5. Magic mids almost give way for scooped parallel-type mids yet still barely bright enough for rock. I start playing a swing line really pulling on the strings by the end of the fretboard. Out of despair, obviously Revelation! This is the best upright-like tone I've gotten so far on this bass! I'll consider this to be added as a setting on this bass. Reflective thoughts: Would the magic mids have to do with a assymetric load provided by the varying resistor values? I did find preference for a 25% higher resistive when load on the bridge pickup when auditining variying parallel resistors added to the idividual pickups (w/o additional connections before the jack)a while back. |
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Post by sumgai on Feb 11, 2011 4:12:03 GMT -5
'never,
Interesting results. But as they say, no one's ears are identical, particularly in what they hear, or to be more accurate, in what they think they hear. Part of that is due to the language of trying to describe what one hears. Probably not my forte, so I'll leave off of that one.
My previous statement, which was a quote of JohnH, is meant to be general. As in almost anything on this Earth, if there's a General Rule, then sure as Gawd made Kyle Is In My Head, there's gonna be an exception. ;D
Then again, my ears are shot, so I'm not the right person to pick up on subtle difference in tonality. Hell, I couldn't find Mojo™ if it was strapped to my nose with a meter of Gorilla brand duct tape!
Say, could you possibly post some sound samples? I'm sure others here wouldn't mind it if you did. Some Nutz like that kind of thing, ya know.... (hint, hint)
sumgai
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Post by roadtonever on Feb 11, 2011 9:36:34 GMT -5
I'd be very glad to post samples! Anything for the cause of taming the tone beast. I didn't mention the added definition in the mids showed up when I overlayed the spectrum of the riff recorded in de-coupled parallel and regular parallel.
Perhaps If you could help me calculate some equivilent resistive values so I'm not comparing apples to oranges. I understand adding resistors in parallel to a pickup is analogous to adding resistor in series, except they react in reverse to the value of said resistor. I hope you see what I'm getting at.
Also any confirmation on the choice of resistor values matching the DCR of pickups. I'm obviously not an EE so that idea was nothing more than a hunch.
My neck pickup is 3.2 Henry, bridge is 4.4 Henry. My cable is 236 picoFarad.
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Post by JohnH on Feb 11, 2011 16:08:34 GMT -5
An interesting study. My statements quoted above are of course, only my opinion/expectation and YMMD!
As to resistor values for magic tones, theres no calculation that I can think of. But just to work out the ball park of what the pickups are doing at 'mid' frequencies, lets take your 3.2H pup, and lets say its DC resistance is 8k. Lets consider 1kHz
The inductive reactance is 2Pi x 3.2 x 1000 = 20100, and this is 90 degress out of phase with the resistance.
Combined reactance is Sqrt(20100^2 + 8000^2) = 21600 = 21.6k
I'm not sure how relevant such a number is, but Id guess that kind of value +/- 200% might be where some action is!
With modelling of pickup curcuits, its easy enough to model the combined impedance of pairs of pickups, but I cant think of a way to represent the loading of one on another, with regard to the differences in the harmonics picked up by two pickup positions. When I think about it, I tend to conclude that you just get an average of what each picks up, modulated by the reactance. I suspect theres more happening though.
In summary, your experiments and your ears are your best tools, and any sound samples that show a difference with the extra series resistors etc would be of great interest.
cheers
John
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Post by roadtonever on Feb 11, 2011 19:57:54 GMT -5
1KHz is a perfect frequency to consider, that's where I heard the magic. I tried to use the formula you outlined and failed misserably. Care to run the DCR of my pickups through it? Neck 11,3k, bridge 17,9k. I'll record 4 clips. Values x1, x2 x.5 and regular parallel with typical 250k parallel load. If anyone wants to request a favorite bass line now's you chance Otherwise I'll probably do a few rock lines like 'Sunshine of your love' and maybe 'Stormbringer'. And a swing line like 'All of Me' of 'Autumn Leeves'. |
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Post by JohnH on Feb 12, 2011 16:36:29 GMT -5
OK, so at 1000Hz, I calculate that a 3.2H and 11.3k pup has a total impedance of Z=23.1k
A 4.4H and 17.9k pup has Z= 32.9k
J
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Post by roadtonever on Feb 16, 2011 12:18:18 GMT -5
Here come the sound clips. Sorry if I kept anyone waiting. The clips can be listened to right in your browser or downloaded as you wish: www.box.net/shared/fg4mmi4zskClips starting with x have the inline resistors according to JohnH's formula. The number after the X is the multiplication factor for the resistor values used. STDP is short for standard parallel w/ typical 250k load(actually 235k). I also made a clip of series for good measure. Exact resistance values used:
Bridge | Neck
x.5 11,6k| 16.5k [11(22-22) |15(22-47) ]
x1 23.1k | 32.9k [23.5(47-47)|32 (100-47) ]
x2 46.2k | 65.8k [47 |68.8(220-100)] |
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Post by roadtonever on Feb 17, 2011 6:52:38 GMT -5
Some notes on differences percieved:
Mids sound livelier and overall more 'convincing' compared to regular parallel. Less honk and scoop. Bloom and dimension are other words that come to mind. Treble responce is attenuated.
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Post by roadtonever on Apr 22, 2011 12:59:30 GMT -5
JohnH, Could you be so kind as to do one more calculation fo me? I've got a new bridge pickup that has an inductance of 5.0H and measures 19,7k DCR.
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Post by JohnH on Apr 22, 2011 15:34:45 GMT -5
sure thing..just gotta remember what it was we were doing....
J
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Post by JohnH on Apr 22, 2011 15:45:01 GMT -5
OK, so my contribution was to calculate an overall pickup impedance based on your Inductance and resistance values, at 1000hZ, which you were using as a basis for the decoupling resistor, x a factor.
With your new values:
5.0H x 2Pi x 1000hZ = 31416
sqrt(31416^2 + 19700^2) = 37081 = 37k
cheers
John
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Post by roadtonever on Apr 22, 2011 15:54:19 GMT -5
EDIT: Did see your second reply. Many thanks JohnH!
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Post by JFrankParnell on Apr 22, 2011 20:56:46 GMT -5
well, I like the series tone, esp at around :25, is that a Watt riff?
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Post by roadtonever on Apr 23, 2011 2:55:45 GMT -5
I'll admit the series setting is what I use the most, gets me the punchyest tones and great grind. Though it benefits from a slightly lower load than the 250k used.
The bassline at :25 is a song from Ozzy Osbournes first solo album, 'Steal Away (The Night)'.
The decoupled parallel setting shines when going for a vintag-ey tone and does the best upright emulation I've found, it makes it sound a lot like a single pickup setup such as a original P-Bass AKA Tele-Bass, also I think it would be easy to for someone to think a hollow-body was used due to the lively singing mids. Again it benefits from a lower load, ideally a no-load setup I've found.
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Still sounded like mud...
really just very similar to the usual 2xpup sound on my guitar.
) But then again, who am I to pee in sumone's Cheerio's? 
If it cranks your turner (as it obviously does for JD), than by all means, go for the gusto. After all, it's neither my money, nor my ears, that are on the line here, right? 
