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Re: If you really want the quack...

5/1/2003 6:11 AM
Steve A.	Re: If you really want the quack... Ryan: The Duck Bucker is a strat-sized pickup, but I suppose that you could mount it in a P-90 soapbar cover (I'm not sure how the holes in the cover would line up with the pole pieces). I was thinking of having a mini-humbucker in the bridge and a p90 in the middle (I have 2 original MH's, 2 Seymour Duncans MH's, 1 p90 and a Bill laurence MH). One switch position would run 1 coil of the bridge with the p90 in the middle to attempt the strat quack. I like the blend positions to be humcancelling if at all possible so you'd want to make sure that when you split the bridge and neck MH's the remaining coil would be RWRP with respect to the P-90 in the middle. For starters make sure that the split coil on the MH's is of opposite magnetic polarity from the P-90. Once you have the magnetic polarities oriented properly, you can always switch the coil wires on the MH's around so that the winding direction is reversed. As to whether or not you will get the "quack", you'd have to try it out... Mark Hammer made an interesting point about the Jerry Donahoe tele using a tone shaping network on a 5 way selector switch to achieve a definite quackness on one of the settings. You might experiment with capacitors in series with one of the pickup coils to see if you can get some quack. --Good luck! Steve Ahola

5/1/2003 6:11 AM

Steve A.

Re: If you really want the quack...

Ryan:

    The Duck Bucker is a strat-sized pickup, but I suppose that you could mount it in a P-90 soapbar cover (I'm not sure how the holes in the cover would line up with the pole pieces).

I was thinking of having a mini-humbucker in the bridge and a p90 in the middle (I have 2 original MH's, 2 Seymour Duncans MH's, 1 p90 and a Bill laurence MH). One switch position would run 1 coil of the bridge with the p90 in the middle to attempt the strat quack.

    I like the blend positions to be humcancelling if at all possible so you'd want to make sure that when you split the bridge and neck MH's the remaining coil would be RWRP with respect to the P-90 in the middle. For starters make sure that the split coil on the MH's is of opposite magnetic polarity from the P-90. Once you have the magnetic polarities oriented properly, you can always switch the coil wires on the MH's around so that the winding direction is reversed.

    As to whether or not you will get the "quack", you'd have to try it out... Mark Hammer made an interesting point about the Jerry Donahoe tele using a tone shaping network on a 5 way selector switch to achieve a definite quackness on one of the settings. You might experiment with capacitors in series with one of the pickup coils to see if you can get some quack.

--Good luck!

Steve Ahola

5/8/2003 8:46 AM
scott	Mandatory vol. roll-off for "Quack" on the higher o/p pups. Vol. pot must have the cap in place. I have 2 examples, one with 2 P-90 w/taps and one with 2 MH both use the Donahue schematic . The 90 N pup just got some A2 pole pieces which increased "Quack", very convincing. I tried P-90 and MH in the 3 pup format. The Donahue wins out. The vol. roll-off was to dark on the manufactored units I checked out.

5/8/2003 8:46 AM

scott

Mandatory vol. roll-off for "Quack" on the higher o/p pups. Vol. pot must have the cap in place.

I have 2 examples, one with 2 P-90 w/taps and one with 2 MH both use the Donahue schematic . The 90 N pup just got some A2 pole pieces which increased "Quack", very convincing.
I tried P-90 and MH in the 3 pup format. The Donahue wins out. The vol. roll-off was to dark on the manufactored units I checked out.

5/3/2003 7:07 PM
LFOscalator	Re: Would a 3- P90 Les paul sound like a strat? Yes, too a certain extent you will get the out-of-phase strat sound with P-90's if you reverse wire the middle pickup. To get a strat out-of-phase-sound requires the middle pickup to be wired with opposite polarity. That's why it is 'out-of-phase'. It's best to do this using reverse wound pickups, but to my knowledge P-90's do not come optionally reverse wound. In other words, you will have to reverse the leads on the middle pickup to get the sound your looking for. But theoretically it should work. LFO

5/3/2003 7:07 PM

LFOscalator

Re: Would a 3- P90 Les paul sound like a strat?

Yes, too a certain extent you will get the out-of-phase strat sound with P-90's if you reverse wire the middle pickup. To get a strat out-of-phase-sound requires the middle pickup to be wired with opposite polarity. That's why it is 'out-of-phase'. It's best to do this using reverse wound pickups, but to my knowledge P-90's do not come optionally reverse wound. In other words, you will have to reverse the leads on the middle pickup to get the sound your looking for. But theoretically it should work.

LFO

5/4/2003 7:14 AM
Steve A.	Good news, Ryan! Over in the pickup forum someone mentioned building a strat with three P-90's and they said that the neck/middle and middle/bridge positions got the "quack" of a regular strat, at least to some extent. Steve Ahola

4/30/2003 2:13 PM
Mark Hammer	Re: What is that strat sound? Although the pickups themselves are not "out-of-phase", that is wholly separate from what the strings themselves are doing. Bear in mind that strings can present signals to the polepieces that are acoustically out of phase (string is close to pickup over one set of polepieces, and away from it over another) simply because of how a string "wiggles" for different notes and where the pickup happens to be underneath the "wiggles" for any given note/wavelength. As a result, the "quacky" tone of a Strat in switch positions 2 and 4 is a function of both the additive tone of the middle and neck or bridge pickup, AND some incidental frequency-sensitive cancellations that occur because of the location of those pickups and the notes being played (and you will note that degree of "quack" is not consistent across the entire fretboard). The same thing occurs with neck+bridge, but the sort of cancellations that occur do not result in "quacky" tones. The Jerry Donahue model Telecaster used two pickups like most Teles (the front one being a Strat pickup rather than a standard chrome-top "rhythm" pickup), but had a 5-way switch that introduced some tone shaping of the front pickup (and I think it was via a series capacitor, but don't quote me) that could produce a sort of "quack" that was very uncharacteristic for a 2-pickup Tele in one of the neck+bridge combinations.

4/30/2003 2:13 PM

Mark Hammer

Re: What is that strat sound?

Although the pickups themselves are not "out-of-phase", that is wholly separate from what the strings themselves are doing. Bear in mind that strings can present signals to the polepieces that are *acoustically* out of phase (string is close to pickup over one set of polepieces, and away from it over another) simply because of how a string "wiggles" for different notes and where the pickup happens to be underneath the "wiggles" for any given note/wavelength.

As a result, the "quacky" tone of a Strat in switch positions 2 and 4 is a function of both the *additive* tone of the middle and neck or bridge pickup, AND some incidental frequency-sensitive cancellations that occur because of the location of those pickups and the notes being played (and you will note that degree of "quack" is not consistent across the entire fretboard). The same thing occurs with neck+bridge, but the sort of cancellations that occur do not result in "quacky" tones.

The Jerry Donahue model Telecaster used two pickups like most Teles (the front one being a Strat pickup rather than a standard chrome-top "rhythm" pickup), but had a 5-way switch that introduced some tone shaping of the front pickup (and I think it was via a series capacitor, but don't quote me) that could produce a sort of "quack" that was very uncharacteristic for a 2-pickup Tele in one of the neck+bridge combinations.

5/1/2003 5:56 AM
Steve A.	Mark: The Jerry Donahue model Telecaster used two pickups like most Teles (the front one being a Strat pickup rather than a standard chrome-top "rhythm" pickup), but had a 5-way switch that introduced some tone shaping of the front pickup (and I think it was via a series capacitor, but don't quote me) that could produce a sort of "quack" that was very uncharacteristic for a 2-pickup Tele in one of the neck+bridge combinations. I have a hunch that this design wasn't just an accident, but that they tried out different combinations of pickups and tone shaping circuits until they got the "quack"... So do you think that they used the series cap with the neck pickup? This may be completely unrelated but in the PSC (permanent split capacitor) motors used for HVAC applications, the run capacitor changes the phase of the voltage and/or current going to the start winding, almost as though it was creating a 3-phase voltage supply from a single phase source. If you measure the AC voltage on the 3 terminals of a single phase HVAC compressor, you will probably get 208-240vac between each of the terminals. It isn't a true 3 phase circuit because the current draw for the start windings is maybe 30-60% of that going to the common windings (with 3 phase the three windings are usually balanced within 5 or 10% of each other). BTW the run cap (anywhere between 5 and 55 microfarads) is wired in series between the run windings (connected to one leg of the 220v) and the start windings (connected to just the run cap). In any case, maybe the series cap on the neck pickup puts that pickup slightly out of phase with the bridge pickup to produce the quack. --Thanks! Steve Ahola

5/1/2003 5:56 AM

Steve A.

Mark:

The Jerry Donahue model Telecaster used two pickups like most Teles (the front one being a Strat pickup rather than a standard chrome-top "rhythm" pickup), but had a 5-way switch that introduced some tone shaping of the front pickup (and I think it was via a series capacitor, but don't quote me) that could produce a sort of "quack" that was very uncharacteristic for a 2-pickup Tele in one of the neck+bridge combinations.

    I have a hunch that this design wasn't just an accident, but that they tried out different combinations of pickups and tone shaping circuits until they got the "quack"... So do you think that they used the series cap with the neck pickup?

    This may be completely unrelated but in the PSC (permanent split capacitor) motors used for HVAC applications, the run capacitor changes the phase of the voltage and/or current going to the start winding, almost as though it was creating a 3-phase voltage supply from a single phase source. If you measure the AC voltage on the 3 terminals of a single phase HVAC compressor, you will probably get 208-240vac between each of the terminals. It isn't a true 3 phase circuit because the current draw for the start windings is maybe 30-60% of that going to the common windings (with 3 phase the three windings are usually balanced within 5 or 10% of each other). BTW the run cap (anywhere between 5 and 55 microfarads) is wired in series between the run windings (connected to one leg of the 220v) and the start windings (connected to just the run cap).

    In any case, maybe the series cap on the neck pickup puts that pickup slightly out of phase with the bridge pickup to produce the quack.

--Thanks!

Steve Ahola

5/1/2003 1:52 PM
Mark Hammer	Hmmmm.... I suspect the selected cap value certainly WAS chosen after extensive testing (which itself may have occurred after a serendipitous finding). Somewhere in my GP collection I have a review of the MIA and MIJ versions of the JD Tele, and it explains what each of the switch positions do. A quick look at Harmony-Central indicates that users describe the #4 switch position as being just like the analogous Strat position (middle+bridge).

5/1/2003 1:52 PM

Mark Hammer

Hmmmm....

I suspect the selected cap value certainly WAS chosen after extensive testing (which itself may have occurred after a serendipitous finding). Somewhere in my GP collection I have a review of the MIA and MIJ versions of the JD Tele, and it explains what each of the switch positions do. A quick look at Harmony-Central indicates that users describe the #4 switch position as being just like the analogous Strat position (middle+bridge).

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