For Acoustic or Cigar Box Guitars (CGB)Low cost, minimum number of parts. Powered 'on' when the guitar lead is plugged in. Easily available parts via Amazon, eBay & others Ideal for Cigar Box Guitars! CBG! |
Electric Guitar Circuits
Cigar Box Guitar piezo film pick-up.Now, that looks different from a piezo disk doesnt it? NOTE. This module has two modes. One is analogue so good for sound and the other is digital and ideal for a stomp box trigger. My kit came with a pcb module but no instructions :\ but was only £4.51 + VAT & P&P (Farnell or CPC) So here is what I found: |
In-Guitar, High Impedance, Sziklai Piezo Preamp
A greater than 4MΩ High Impedance audio preamp
Suitable for piezo disk, piezo film or piezo rods in Cigar Box Guitars CBG
Optimal impedance matching brings up the bass, and cuts the tinniness. Period.
High Impedance Matching (Piezos)
Why Your Piezo Pickup Might Sound Weird (And How to Fix It)
Ever plug in your guitar and wondered why it sounds thin, harsh, or just... off? If you’re using a piezo pickup, the problem might not be your playing or your gear, it could be impedance mismatch. Yeah, it sounds technical, but stick with me. This one tweak can seriously upgrade your tone.
What’s the Deal with Piezo Pickups?
Piezo pickups are a bit different from the magnetic ones you find in most electric guitars. They use crystals to pick up vibrations directly from the guitar’s body, which gives them a super detailed, percussive sound. Great for capturing the nuances of fingerpicking or strumming.
But here’s the catch: piezos have very high output impedance. Think of impedance like water pressure in a hose—if the pressure’s too high and the hose isn’t built to handle it, things get messy. Same idea with your signal chain.
Why Impedance Matching Matters
If your piezo pickup is sending a high-impedance signal into gear that’s not ready for it (like an amp or interface with low input impedance), you’re going to run into problems:
- Signal Loss: Part of your signal just vanishes. You’ll hear it as a weak, lifeless tone.
- Weird Frequency Response: Some frequencies get boosted, others disappear. Your guitar starts sounding like it’s underwater.
- Noise and Distortion: You might get buzz, hum, or even unwanted distortion. Not the good kind.
The fix? Use a high-impedance input.
Often called “high-Z", these are designed to handle piezo pickups properly, usually rated in the megaohm range meaning that your signal gets through cleanly, with all the sparkle and detail intact.
Enter the Buffer: Your Tone’s Secret Weapon
Even if you’ve got the right input, long cables and pedalboards can still mess with your sound and that’s where buffering comes in.
A a piezo buffer or preamp is a tiny high-impedance circuit that sits between your pickup and the rest of your gear. It fixes the impedance and boosts your signal just enough to keep it strong and clean as it travels through cables, pedals, and whatever else you’ve got in your rig.
Here’s what piezo preamp does for you:
- Keeps Your Highs Crisp: Without a buffer, high frequencies can get lost. Your tone turns muddy. A buffer keeps the sparkle.
- Gives the bass end rich deep tones.
- Fights Cable Drag: Long cables = signal loss. Buffer = signal stays strong.
- Reduces Noise: Buffers help isolate your pickup from noisy electronics, cutting down on hum and buzz.
Final Thoughts
If you’re serious about your tone, especially from piezo pickup, don’t ignore impedance matching and buffering. It’s not just for gear nerds. It’s for anyone who wants their guitar to sound the way it’s supposed to: rich, clear, and full of life.
So next time your acoustic-electric sounds like it’s been run through a blender, check your input impedance. Add a buffer if needed and your ears will thank you.
What are they, what are they for and how do they stack up? We explain. |
Piezo guitar test using audio transformer.
Using an LT44 is sometimes seen in scientific piezo circuits, so I put it on test.
We can use an audio transformer LT44 (£4 on eBay) to change the impedance of the piezo from 'high-ish' to medium.
I put it on test, so you do not have to..
Positioning / Mounting Piezo Pickups on Cigar Box Guitars
Conditions Of Test: Used a Cigar Box Guitar CBG.
These tests used a proper impedance-matched active preamp: this one: Sziklai Piezo Preamp, and so the 'tinniness' associated, with using piezo pickups simply directly connected (or using a 'so called' passive-preamp), was not apparent.
The results below are my subjective assessment and all tests used the same pickup, guitar and amplifier on the same day. No 'Piezo Quack' was observed at any time.