POOP, SOOP, PHOOP & SHOOP

[axedoctor]

when modding a Strat, which of these out-of-phase possibilities do you think adds the most tonal value and why?

how would you rank them in order of preference for allocating switching resources?

[JohnH]

I'm going to write a song where three girls with beehive hairdos sing that in harmony.

Id say Soop, with something like a bypass pot on one coil to knock it off balance to make Shoop.

[axedoctor]

interesting ... plenty of observers, but not many opinions


JohnH -

To be honest, I have a hard time understanding the impact of phase reversal with a series connection as opposed to the more simple mathematical visualization of the parallel connection - thus the motivation to pose my question about satisfaction (or not) with the sound outcome of the various out-of-phase possibilities.

SOOP seems to come for free with most designs that incorporate series combinations of pairs of single coils (SIP) and POOP ... ooh, I fear there's a disturbing lyric in here somewhere. 

From what I've been able to gather, PHOOP (with the proper series capacitor selection) can provide an interesting variation to the standard PIP while POOP (perhaps understandably) does not appeal to many with the exception of those seeking to produce some funk rhythm sounds. 

Adding SHOOP to a design that I have been working on comes at a resource expense that I am not comfortable with unless it would provide some significant tonal value, but I decided to ask for some guidance here before making my final decision.

[pj]

I think when it comes to any Hoop be it ser/par the ideal tweak for you needs to be dialled in. Just right is usually enough, the other shades are just too vanilla. With that in mind I think John's idea of a partially shunted series coil is fantastic, understand the cost concern you have for the ergonomics but if you find the perfect shunt value you don't need the pot.

Years ago I had the Dan ARsmtrong seven sound set up on my strat with a set of Bill Lawrence's. I was given a box of old electronic bits by a neighbour and in it were some nice four pole three way rotary switches with knurled shafts. So I used one to give me standard, the Armstrong sounds, and then flip the phase of the middle so I had SOOP too. It was just too much cancellation and notching for me so I had it shunting a 100k preset pot across in that position and that was the goldilocks spot once I had it tweaked and nail varnished in position.

[sumgai]

Mar 18, 2018 14:50:32 GMT -5 pj said:

.... and that was the goldilocks spot once I had it tweaked and nail varnished in position.

Stand aside Mojo, here comes Goldilocks!



Thanks, pj, you made my day!

---

ad,

I have to say, OoP sounds are, like all other aspects of an electric guitar's sounds, purely subjective. I for one don't particularly like any of them, although I've devised designs incorporating them - for other people. Asking someone like me "which one is best" is a non-starter... for me. But others here, and elsewhere on the web, they live for that kind of thing, true enough.  As for your lament about how few responses you've seen, just wait awhile, I'm sure more Nutz will evenutally see your post, and if they're like you, they'll chime in.

sumgai

[stevewf]

Mar 15, 2018 14:25:45 GMT -5 JohnH said:

Id say Soop, with something like a bypass pot on one coil to knock it off balance to make Shoop.

Bypass pot, yes! But how?

I haven't been able to make that bypass pot work. Anyone show me a schematic or wiring diagram?

I wanna apply it to my SSS Strat.

I think the next detail about this guitar is irrelevant, but I'll include it just in case I'm wrong: the guitar has the Free-way 5B5-01 in it, wired pretty much vanilla per Free-way's website (SSS Parallel Series Scheme A 1V/1T).

I'd like to be able to swap the phase of the bridge pickup by using a push/pull 2P2T switch hidden under the "third" pot. Phase swap is easy; a little criss-cross pattern of jumpers between the switch terminals, done. But the next part has me scratching my pick guard.

I wanna be able to use the pot that's attached to the switch to sweep from OoP to HOoP. Or maybe in between, like from "majority out of phase" to "half out of phase", if that could possibly make sense. In essence, the pot would blend two channels: 1KOhm/0.01uF and 6.2KOhm/0.02uF.

So, in total:
1) Push/pull down. The bridge coil is in its normal phase. No shunting, no damping.
2) Push/Pull up. The bridge coil's phase is swapped.

• With the pot at full CW, the signal passes through 6.2K-0.02uF (series) in series with the coil. (Half OoP)
• With the pot at full CCW, the signal passes through 1K-0.01uF (series) in series with the coil (Maj OoP)
• The pot sweeps between the two extremes. Meaning that the output is a mix of the two paths, with the pot affecting the bias. Is this called blending?
• Of course, there's some leakage unless there's a no-load pot - see Bonus complication

Bonus complication: on this Strat, I favor hat-shaped knobs. That means push-push instead of push-pull. In the push-push world, there are limited resistance curves available; all I've found are 250K and 500K logs by Bourns. I hack Bourns pots regularly, and swapping wafers would be easy, except the push-push wafers are not their same standard.  Any other push-push pots out there?

I tried to create the circuit using a 250K analog pot, but I've been disappointed in the results; everything works, but with the switch up, it all sounds Maj OoP, and the pot has tiny effect (and only in the middle of its sweep!).

Drawings: Sorry, I have only hand drawings on paper, and I'm not sure how best to share what I've tried already.

[newey]

stevewf:

I haven't worked out a diagram for this, but it sounds like what you want to do is going to require a dual-gang pot, like a blend pot, to get the two different effects you want here. This means procuring a dual-gang pot with a push/pull switch, which are rare birds. And, I've never seen one with a push/push switch.

Although perhaps someone else has an idea for a regular single-gang pot that I'm missing.

[Yogi B]

Oct 13, 2021 2:09:44 GMT -5 stevewf said:

• With the pot at full CW, the signal passes through 6.2K-0.02uF (series) in series with the coil. (Half OoP)
• With the pot at full CCW, the signal passes through 1K-0.01uF (series) in series with the coil (Maj OoP)

Firstly I've got to query your cap choices. For the predominantly OoP sound you want closer to a full blend of the two coils and therefore less series impedance from the resistor & cap, okay so what's the hang-up? Capacitance is inversely proportional to impedance; thus, for less additional series impedance in the majority OoP setting you require a larger capacitance.

Alternatively, you know the above and it was simply a typo (0.01uF instead of 0.1uf) — this assumption is additionally supported by the fact that the difference between 0.01uF and 0.02uF would result in a relatively small change. But honestly you'd probably want to go even larger, say 0.22uF—0.33uF (splitting that range with 0.27uF is what I went with below).

The pot sweeps between the two extremes. Meaning that the output is a mix of the two paths, with the pot affecting the bias. Is this called blending?

It's a kind of blending, but more like series blending than parallel blending. (From the world of pedals, the first thing that springs to mind as being schematically similar is the "Range" control of the Catalinbread Naga Viper.)

Now that's out of the way, how about a diagram? This is what I'm thinking:

When in-phase the pot and additional components are entirely out of the circuit. With the push-push engaged R1, C1, R2 & C2 are added in series with the reverse-phase bridge pickup, giving (when combined with another pickup) a HOoP tone — turning the pot contra-clockwise gradually shunts R2 & C2 leaving just R1 & C1, giving the majority OoP tone.

[stevewf]

Oct 13, 2021 9:12:19 GMT -5 Yogi B said:

Firstly I've got to query your cap choices. For the predominantly OoP sound you want closer to a full blend of the two coils and therefore less series impedance from the resistor & cap, okay so what's the hang-up? Capacitance is inversely proportional to impedance; thus, for less additional series impedance in the majority OoP setting you require a larger capacitance.

Alternatively, you know the above and it was simply a typo (0.01uF instead of 0.1uf) — this assumption is additionally supported by the fact that the difference between 0.01uF and 0.02uF would result in a relatively small change. But honestly you'd probably want to go even larger, say 0.22uF—0.33uF (splitting that range with 0.27uF is what I went with below).

Ok, now THAT is a fast, comprehensive response! Especially considering how hard-to-read I can be...

I think Yogi B found the biggest part of my problems: wrong cap choices, by orders of magnitude (for some reason, I thought I read them in phostenix's drawings...). Yogi, your experience is gonna save me lots of time experimenting, thank you. The battered, kinked strings of the guitar thank you, too, for reducing the number of times the pickguard gets pulled out from under them.

And thanks very much for the schematic - again, very quick. And it helps me understand when ppl use the word "shunt" - now that you've shone the showing light, I shan't shun the shunt.

I promise to post results when I get time to re-solder. Today is full of horrible time-suck obstacles (i.e. non-guitar-related tasks).

[Edit: it'll be a while. When I finally got free time, I notice that I don't have in my possession caps in the right range , so we're waiting for those to arrive. Darn]

[stevewf]

Oct 13, 2021 5:33:39 GMT -5 newey said:

stevewf:

I haven't worked out a diagram for this, but it sounds like what you want to do is going to require a dual-gang pot, like a blend pot, to get the two different effects you want here. This means procuring a dual-gang pot with a push/pull switch, which are rare birds. And, I've never seen one with a push/push switch.

Although perhaps someone else has an idea for a regular single-gang pot that I'm missing.

Thanks, newey! Yogi B seems to have found a single-gang solution. Yes, dual-gang+2P2T pots are not easy to find, especially in different tapers. I've had a hard time finding reverse audio tapers in general, and 1M reverse audio is particularly hard to find. This is why I started disassembling/reassembling pots. I actually bashed two DPDTs onto one pot (photo: www.flickr.com/photos/187388486@N07/49648951892/in/dateposted-public/)
though it's not reliable enough that I would put it in any guitar not owned by me (and necessitates a deep cavity).

Like newey, I haven't seen a dual-gang push-push (Bourns calls it "latching push"). I tried to replace one's wafer with a wafer that came with their push-pull - not cross-compatible. All new parts, including the threaded bushing. Woulda involved some modding that I didn't wanna get into (un-riveting the center lugs off of the two chassis, moving a connector from one chassis to the other, re-riveting the lug... too much risk of futility).

I actually wrote to Bourns to beg them to make the full assortment of wafers for their push-latching pots. Right now, they only make 250KA and 500KA. Bass-cut knobs are better when 1MRA in my opinion, and most blending applications will be "cleaner" with high-resistance traces, if my theories are accurate. So, Bourns, please!