Again trying wiring based on a humbucker pickup. This time with results. Instead of stacking the two piezo they are side by side. One facing up the other down. Wired as shown below and directly to an output jack.
Placed between two pieces of corrugated cardboard and pressed inside a cbg. Exposed and at 12 inches from a small amp speaker. Amp set at 1/4 volume. The hum level was no different from what the amp normally has. There was no squall. Not even when strumming the guitar.
Control. The open guitar nor the amp was moved. Nor was any of the setting different.
A single piezo sandwiched in the same corrugated cardboard. Wired directly to an output jack. Placed inside the very same cbg. Squalled uncontrollably. Was not able to hear when I strummed the guitar. Squalling didn't change.
The wiring is as the gif below. One hot running to ground. The other to the hot side. The two black ground wires are soldered together and go nowhere.
Hoping other builders would try this to see what results you folks can get.
Going to try this again tomorrow ( when it's not 3:00 in the morning ) Going to try with both piezo facing the same direction. To see if there is any difference in sound or effect.
Tags:
Looks like one piezo is acting as a dummy coil. It's not wired in series, but a variation of parallel. What's the grey box that the black wires are going to?
Some guitars like the Gibson or Epiphone Blueshawk have P90 single coil pickups with a 3 pickup under the top without magnets or poles and is used as a dummy coil to buck hum while still having single coil tone.
The two black wires from the piezo are soldered together and shielded and go nowhere. I treaded those like the inside wires of a humbucker.
The two red wires I treated like the the two end wires. Making a mock humbucker out of two piezo.
I was able to turn the amp up half way today before I got squall, Squallbucker still at 12 inches away wile the strings were being strummed. Then one of my leads broke. Those little things are just not meant to be yanked around. : )
A series wiring would be signal through hot of piezo 1 - piezo 1 ground to hot of piezo 2 - piezo 2 ground to ground. That doubles the impedance and isn't good.
Parallel wiring would be both grounds to ground and both hot/signal to signal. Which half's the impedance like when using 2 8ohm speakers turns into a 4ohm load.
So your sending signal through piezo 1 into piezo 2 backwards. That's why I was mentioning that it's acting like a dummy coil. It's cutting the noise like a humbucker without doubling the impedance.
Very interesting.
yes, just like a dummy coil on a humbucking pickup. I'm really hoping others will try this and see if they get the same results. If this works and sounds good it will be a way to use a piezo at louder volumes when playing live. It's still microphonic in nature. Still doubt you would be able to use distortion at high volumes.
The reason I turned one upside down was to try to emulate the reversed magnetic field of the dummy coil.
Hi, interesting stuff. I'm not very clever when it comes to pickup specs, and you guys seem to know your stuff in that regard.
Do piezo crystals have a magnetic quality like the north and south poles of a humbucker?
When testing my magnetic pickups one coil reads south (wound) and the other reads north (wound), and when wired together give the hum cancelling effect. When I test the piezos there is no magnetic field.
I understand the piezo crystals are sandwiched between two plates and are effected the same from either side by string vibration, so may not have the same hum cancelling properties, but you said it did, I'm intrigued. And possibly wrong in my thinking.
Taff
you are probably getting a phase cancellation effect. would be interested to hear the tone of this pickup up and down the fretboard compared to a single piezo .
like a half cocked wah pedal.. frequencies dropping out and returning as the pitch goes up and dow,..
Taffy, piezo are not magnetic. They transfer all vibrations into an electrical signal. This is why it's way to easy to get a lot of feedback and squalling when playing live at higher volumes. Didn't notice any hum cancellation. Because RMF fields (what causes the hum ) are magnetic I really don't think there is any way possible to cancel them out with a piezo. However the feedback and squalling was greatly reduced.
Timothy, The first experiment I did, stacking the two piezo, gave very noticeable phasing. This experiment I didn't notice it, Or was to excited from the lack of squalling to listen for it. : ) I'm going to make a wood sided pickup and place it in a CBG. Plan on playing this trough my 80 watt Marshall. This amp as a clearer sound to it. I'll be able to hear if there is any phase cancelation.
Thanks CTBR, sorry I miss read your account.
Yes feedback is a problem with amplified hollowbody instruments, nowadays there are "feedback busters" that block the soundhole limiting air movement, and preamps. Back in the day I would occasionally get guitars for repair that had been filled with cotton wool to limit feedback. I also had to devise ways to block the "f" holes in arch top guitars for the sams reason.
Taff
I'm thinking that adding another piezo in this way is having the 2nd piezo act like a resistor or capacitor that reduces the impedance, but I'm not sure.
Thanks CTBR, sorry I miss read your account.
Yes feedback is a problem with amplified hollowbody instruments, nowadays there are "feedback busters" that block the soundhole limiting air movement, and preamps. Back in the day I would occasionally get guitars for repair that had been filled with cotton wool to limit feedback. I also had to devise ways to block the "f" holes in arch top guitars for the same reason.
Taff
Another way to stop magnetic pickup squeal is to wrap the bottom and sides of the pickup under the top of the guitar with foam. I did this with the bridge pickup in my Strat-O-Res guitar. I just totally covered the bottom and sides with some black foam and secured it with electrical tape. It 's just like stuffing the guitar with foam/wool, but this doesn't block any acoustics in the body like the foam/wool would do inside the guitar.
Tried this experiment with both piezo facing the same direction. Did not work as well. Also tried it backwards, with the wrong side of the piezo down. This had less volume. Comparing the squallbuster with the sound of just one piezo. Same sound. Same volume. The only difference is the point when you get feedback and squall. With the squallbuster I was able to get my small amp up to 9 1/2. With the single piezo I was able to turn it up to 6. Both are still wrapped in the same cardboard. I know I'll get a better total response with wood. But possibly more feedback at a lower volume.
To answer the phase question i didn't hear anything like a coked wah or a shifting of an out of phase signal. The tone and volume between the single piezo and the squallbuster was the same no matter where I placed them in the box.
Next will be to place this in wood and do the same experiment. Moving both around in the box and comparing the tone. And bringing each to the point of squall. I want to do more experimenting before I glue one to the inside of a CBG. So far I'm very happy with the less squalling aspect of this pickup design.
For fun I did try it with the amp's built in distortion. Nope, it's a piezo pickup and this just isn't going to work with distortion.
Started by J. D. Woods in Performances, How to Play, Lessons, Concerts. Last reply by BrianQ. 20 hours ago. 4 Replies 0 Likes
Started by Southern Ray in Other stuff - off topic, fun stuff, whatever. Last reply by A.D.EKER on Wednesday. 4 Replies 0 Likes
Started by Rich Butters in Building Secrets, Tips, Advice, Discussion. Last reply by Crazed Fandango on Tuesday. 4 Replies 0 Likes
Started by J. D. Woods in Performances, How to Play, Lessons, Concerts. Last reply by J. D. Woods Apr 20. 7 Replies 1 Like
Started by Nomad Jack in Performances, How to Play, Lessons, Concerts. Last reply by J. D. Woods Apr 17. 7 Replies 2 Likes
Started by Moritz Voegeli in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Apr 14. 6 Replies 2 Likes
Started by Timothy Hunter in Other stuff - off topic, fun stuff, whatever. Last reply by Timothy Hunter Apr 10. 14 Replies 3 Likes
Started by Tom T in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Apr 9. 9 Replies 0 Likes
Started by Southern Ray in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Apr 4. 7 Replies 1 Like
Started by Timothy Hunter in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Mar 27. 1 Reply 2 Likes
Started by Taffy Evans in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Mar 10. 1 Reply 3 Likes
Started by Cigar Box Nation in Feature Articles. Last reply by BrianQ. Mar 9. 4 Replies 3 Likes
Started by Ghostbuttons in Building Secrets, Tips, Advice, Discussion. Last reply by Timothy Hunter Mar 9. 5 Replies 1 Like
Started by Justin Stanchfield in Building Secrets, Tips, Advice, Discussion. Last reply by Taffy Evans Mar 8. 6 Replies 0 Likes
Started by Ken I in Building Secrets, Tips, Advice, Discussion. Last reply by Brian partington Mar 8. 8 Replies 0 Likes
Started by Southern Ray in Cool gear discussion - that's not cigar box related. Last reply by Southern Ray Mar 6. 5 Replies 0 Likes
Started by Taffy Evans in Other stuff - off topic, fun stuff, whatever. Last reply by Taffy Evans Mar 5. 4 Replies 2 Likes
Started by Justin Stanchfield in Building Secrets, Tips, Advice, Discussion. Last reply by Carl Floyd Mar 1. 15 Replies 0 Likes
Started by Joe in Performances, How to Play, Lessons, Concerts. Last reply by Carl Floyd Feb 29. 13 Replies 0 Likes
Started by Chance in Building Secrets, Tips, Advice, Discussion. Last reply by Southern Ray Feb 22. 12 Replies 1 Like
Posted by Vlad on March 31, 2024 at 11:48pm 0 Comments 1 Like
Posted by Vlad on March 6, 2024 at 2:32am 5 Comments 2 Likes
Posted by billy jones bluez on February 28, 2024 at 2:09pm 0 Comments 0 Likes
Posted by billy jones bluez on February 17, 2024 at 11:00pm 0 Comments 0 Likes
Posted by Vlad on February 11, 2024 at 1:06am 1 Comment 1 Like
May 11, 2024 from 11am to 8pm – Speakeasy Grill
0 Comments 0 LikesMay 30, 2024 from 6:30pm to 10pm – The Casual Pint of Huntsville
0 Comments 0 Likes© 2024 Created by Ben "C. B. Gitty" Baker. Powered by
Cigar Box Nation is presented by C. B. Gitty Crafter Supply, your one-stop-shop for Cigar Box Guitar parts and accessories!