Piezo Pickups

Discussion in 'Pickups & Electronics [BG]' started by LowEnd Theory, Jun 9, 2005.

  1. LowEnd Theory

    LowEnd Theory

    May 31, 2005
    Hey people,
    Can anyone shine their beacon of knowledge toward the dark docks of my brain 'cause i cant see here.... :confused:
    sorry for being an idiot,
    but if given the choice do i want a bass with piezo pickups or not?...
    and why or why not?...
    thanks, yer swell...

  2. luknfur


    Jan 14, 2004

    piezo can add a percussive tone and some mellow/hollow highs to tone. Whether that would be useful to you or not is up to you. Typically there's simply a volume control for piezo so you can cut it off completely if you don't want it. Can't really think of a downside to having it unless they want to rake you over the coals for the difference, although it is one more thing that can break. To me it's more of an accent tone that can be a nice plus but nothing I couldn't live without or have developed any love or dependency for. Some guys really like them though.
  3. I have piezos on my Dingwall SuperJ. I had sheldon install RMC w/ a polydrive and 13pin out. A few thing come to mind when your playing the piezos only. They are bright, bright, bright, and pickup a ton of string noise. I find they add a very unique tone to fingerstyle, but are too harsh IMO for slap playing, all highend little bottom. When mixed w/ mags they sound great, and honestly you can use them in a number of styles where you want pronounciation & good definition in your playing.
  4. Marcus Willett

    Marcus Willett Supporting Member

    Feb 8, 2005
    Palm Bay, FL
    Endorsing Artist: Bag End - Dean Markley - Thunderfunk
    Usually they are because there is a phase shift introduced by piezos (this is an area of disagreement among some) that results in the over-emphasis of the high end because it is heard so much sooner. My Wendler has a passive peizo system and is not bright at all.

    If you feel so inclined:


    NCI at all, just a satisfied customer.
  5. martens-koop


    Oct 10, 2002
    Just to chime in, I have heard a few different types of piezo's, and in my opinion, the only brand that I'd go with if you wanted the option to use them by themselves is RMC... On my next bass, I'll have piezo's installed, and if my past experiences hold true, I'll probably use them half the time by themselves, and the other half of the time I'll use them blended with the magnetic pickups...

    you should definately inquire as to how they will be buffered. there are several different modules available where you run the magnetics in one side and the piezo's into the other side... the resulting outputs can then be blended or switched at your discretion and will match up well. most of my experience is with the bartolini MPB1 (which probably stands for something like "magnetic piezo buffer 1" but could also stand for "musically pure butter". they have an 18volt and a 9volt model... RMC also offers such a device... I'm not into the whole multi-pin out thing, because I'll never be able to afford a midi processing unit of high enough quality to make me happy... I'm pretty sure though that the unit on franks bass does not require that you install the multi pin out jack...

    anyways, all of my experience is with custom jobs and have never played any factory installed production basses with piezo's...

    if you can afford it, I'd say go for it... its an option that you might really appreciate down the road.

  6. Peter Weil

    Peter Weil Seeker of The New Supporting Member

    Mar 29, 2000
    Edinburgh, Scotland
    I also have some expereience with piezo's.

    My first experiment was building my own pickup out of a piezo buzzer from a musical birthday card that I received - just to get a feel for whether I would like the tone. As it turned out, I did, even without buffering the signal properly.

    Want to do something similar? - then look here: http://www.talkbass.com/forum/showthread.php?t=131882&

    After that, I decided to put my money where my mouth was, and after looking at the options available, I went with the Graphtech FAAS system (as it was then known - this included their bridge saddles and preamp).

    To put it simply - I was delighted with the results. I retro-modded it onto my old Peavey G-Bass (which had a funny little 'hump' in the low mids that I always disliked) and ended up using it a great deal on songs that allowed for a 'detailed' bass sound (slapping, jazz, etc).

    In fact, I ended up liking the sound (lots of highs, lows, and detail, including a little finger noise, but not too much) so much that I eventually just went to using the piezo sound only.

    After I acquired a Hamer Cruise 2Tek, what I've done with the Peavey more recently is string it up as a tenor bass (ADGC) and use the piezos as the only pickup source. It sounds great!
    Nonetheless, I found myself missing the 'brown' sound of a magnetic pickup and so I eventually ripped out all the active electronics (which I dislike - I like the 'airy'/'open' sound of passive pickups) and replaced it with a single Bartolini W4CBC (their version of a Washburn Bantam bridge pickup).

    I've just finished that mod, and I love the combined sound. So much so that my next project bass is going to be a Fender Jazz type bass with passive mag pu's and either the Graphtech or the RMC piezo system (with an appropriate buffer).

    Well, that'll do for now. Good luck!

  7. dave251

    dave251 Wendler Instruments

    Feb 5, 2004
    Lawrence, KS
    The main advantage to a piezo is the WIDE frequency response....the frequency response itself is flat down to about 10hz, and on the high end way past 20Khz....most of the internal resonance is up in the radio frequency band, beyond human hearing. A typical magnetic pickup, on the other hand, falls off severely below 200hz, and peaks in the 3Khz to 5khz range...not flat at all, but it IS a tone we are all familiar with.

    Ceramic piezos do have a strong output too...can typically be used without a preamp, if volume is your only concern....


    There are several problems introduced with a piezo.

    The first and foremost is that they are HIGHLY capacitve, in addition to producing a voltage. What this means is the highs are passed first, during the onset of the attack transient, while the lows are "held in check" for a few milliseconds....that translates to the typical harsh bright tone we associate with them. This is often referred to as phase shift. SEVERE phase shift during which several full cycles of highs can pass before the first cycle of lows has barely started.

    This results in most of the energy of the attack transient as a high frequency "burst"....which brings about.....

    The secondary problem is the strength of the attack transient itself....it's actually more dynamic than the player's input...if you hit it hard enough, all of the harsh, bright upper partials will tend to be overemphasized, while the mids and lows sound compressed....during the attack transient. This is the "piezo quack" we all hate about the things.

    There are solutions. Just a "buffering preamp" is not a solution, but a band aid. If you insist on using active electronics, you will need to find a preamp that corrects the inherent phase shift/attack transient anomaly. The old FRAP system is the only one I'm aware of...although I believe the Trance Amulet system does some of this too. A very expensive proposition, I might add...

    Another solution is to rout the signal from the piezo through an inductive device....this acts like a "shock absorber" and slows down the ultra fast high frequency response of the piezo.

    And it just so happens most electric basses have one on board...it's called a magnetic pickup....works great when used in a PASSIVE combination with the piezo (MUST be passive for the signals to interact with each other).

    Some clips of my passive "MagPi" system:


    http://www.electrocoustic.com/audio/Stomper Strut 61305.mp3

    http://www.electrocoustic.com/audio/All of Meando.mp3
  8. luknfur


    Jan 14, 2004

    interesting info. I just happened to have a bass with piezo's (not hooked up) and a set of Bart Rics for an upcoming Ric comparison so I took the piezo's and wired them into the pigtail of the 4 lead bridge HB pup. No problems but without being able to A/B it I couldn't tell a tonal difference. I may stick a switch in it so I can cut the piezo's in and out after I do the Ric run.

    Would a mute pup accomplish the same thing with the piezo?
  9. Rick Turner

    Rick Turner

    Jul 14, 2004
    I would sure like to see proof of all this talk about phase delay coming from piezo pickups. I just don't buy it. I don't hear it, and the crappy sounding piezos that are so much out there don't sound crappy because they are piezos, but rather because they are poorly designed piezos.

    Hey, I've been widing magnetic pickups since 1969 and making piezos since 1988, so what do I know? What I know is that with piezo crystal pickups, 95% of the ones I've seen have hopelessly bad geometry with regard to isolation and string vibration input to the piezo element. The phase problems come from allowing too much crosstalk the couple mechanically to the pickup.

    IF piezos are done right...and by that I mean correct geometry and correct electronic interface, the phase response is excellent...better than magnetic pickups. The frequency response is whales to bats, and there's absolutely no problem with low end. I'll put my Electroline piezos up against any magnetic pickup any place, any time for frequency and phase response.

    Dave, I think you just haven't hear what can be done with piezo design.

    Also, if there's a phase problem with pickups (and there is), it's with magnetics. Mag pickups are just slow, that's all! They don't have to be, but most are.

    Piezos harsh? That's bad piezo design AND the fact that with piezos, you have response that goes way up there. You are hearing everything the string is doing.

    I'd also like to point out that anyone playing an electric bass is playing active. The only issue is at which end of the cable the first active stage is to be found. Pickups make crappy line drivers. That includes piezos, magnetics, and any combination thereof. With passive instruments (unless they're truly passive low impedance as per the old Les Paul Low Z instruments), you have cable losses that include screwed up frequency response, loss of voltage, and induced noise. Not that passive can't be fine, but I think that trying to take the higher ground by slamming active instruments is just dumb. You're just as likely to have a bad first preamp stage in a bass amp at the long end of the cable. Of course there's a lot of crap in active instruments. But there's some good ones, too, and they exhibit better frequency response, better phase response, and a wider tonal pallette than passive instruments ever can.

    Dave, I admire what you're doing, but I question your arguments. Yes, I do know how terrible most piezo pickups sound. That's not because of inherent phase response, it's because of poor mechanical design. Believe me, been there, done that, learned from it, never do it again. I've solved the problems, and I'd be happy to discuss the solutions.
  10. dave251

    dave251 Wendler Instruments

    Feb 5, 2004
    Lawrence, KS
    Hey Rick....

    I think you and I can agree that piezo material is HIGHLY capacitive. In that regard, we both know that a capacitor in series in a circuit tends to limit lower frequencies. Of course, the difference with a piezo is that it produces a voltage...not much current, but can produce a very strong voltage spike nonetheless. And this voltage spike is almost all high frequency response.

    So when we stroke the string, and the piezo reacts, particularly during that attack transient, the signal is high frequency weighted FIRST, while during the steady state, it all settles back into a nice flat frequency response.

    Of course with a magnetic pickup, being highly inductive, the highs tend to get lost, especially in the higher impedance designs. And I won't disagree there is more phase shift of the magnetic pickup, and the higher the inductance, the more the phase shift occurs....

    But my point is, the phase shift is in the opposite direction from the piezo, and the two signals, when mixed passively will tend to complement each other.

    So what we hear in the "steady state", that is, the sustain portion, can have relatively flat frequency response...but those first few milliseconds from the piezo, the attack transient, can be balanced out with the use of the inductive coil.

    While so much is made of sustain regarding stringed instruments, I believe it is the attack transient that hooks us...that initial onset of vibrations is what grabs our psyche...what allows us to differentiate between a flute and a clarinet, between a mandolin and a twelve string....and I'm designing for THAT moment, the natural connection with the least amount of electronic manipulation. Growing up with acoustic instruments as the defining "tone", I'm actually more interested in extending the feel, the touch response, from the player all the way through the amp chain. To me, that's entails the fewest gain stages possible, and thus the passive mixing system( what I call the "MagPi"). Then if we can keep the gain stages to a minimum, say three or four( my first tube amp attempts were three gain stages in pure Class A...wasn't efficient enough) in a push-pull tube circuit....this just keeps the player closer to the end product. And more in touch with what's coming from the speaker system.

    I would never argue with you regarding the various quality issues regarding either piezos or coil/magnet design; I see it as a difference in philosophy in how to reach essentially the same goal: A responsive instrument for the player to connect with. While your designs( and this is just my personal observation ) tend to use technology to "correct"(and to even enhance) inherent issues with instrument pickup design, I tend to go in the opposite direction...ie, the simplest materials into the simplest circuit in the attempt that an instrument that is responsive to the human condition at the most basic levels will be the result.
  11. elros


    Apr 24, 2004
    Proprietor, Helland Musikk Teknologi
    Mr. Turner, just for the record I'd like to ask:

    Is it so that you're willing and able to supply a piezo system to my luthier for installation on a custom built bass?
    If so, is it available for 6+ string basses?

    thanks a lot,
    Hallgeir Helland
  12. Rick Turner

    Rick Turner

    Jul 14, 2004
    I am only making piezos for my own instruments right now as I had problems (cost and delivery time) with my former supplier of bridges. I'm working on machining my own bridge saddles to use with an import bridge base plate. Nothing yet, though.

    Dave, I just don't hear it how you explain it. With a DC couple system, I can demonstrate smooth response down under 10 Hz with no sonic problems of highs slapping you upside the head. Piezo pickups are fast, fast, fast. Yes, they're much faster than magnetic pickups, but that's because if you couple them to the strings correctly, they're more accurately tracking the string motion in time. The real issue here is that magnetic pickups are slow, and many folks have just gotten used to that, so a piezo, even one which has great low frequency phase response, is faster than you're used to.

    Look, I know all that stuff about capacitors and inductors and what they do to phase response. But that doesn't take into account that in this case, the source is not necessarily passing through a cap...it is one. What you're saying is like saying that condensor mics have crappy phase response when, in fact, they have much better phase response than do dynamic mics which are slow, slow, slow. Now that doesn't mean that an SM-57 may not be a good choice in some cases, but I'll take a Schoeps CMC-6 or a Neumann 140 any day for capturing the essence of an acoustic guitar over the dull sounding dynamic mic.

    If you couple a string to a piezo ceramic block properly, and then buffer it beyond the beyond, you'll get phase accurate low end you just wouldn't believe. Too much, in fact, as having a pickup that's flat much below 30 Hz (which is really easy...) will just pick up a lot of rumble and noise.

    Dave, I doubt that you've heard any of my "Reference Series" piezos as I use on my Electroline basses and sometimes use on Renaissance guitars. When and if you do, I think it will change your theories about poor phase response in piezos.

    This is like the our whole argument a couple of years ago re. phase response of pickups in acoustic instruments. It's the instruments that are slow acoustically, not the pickups being too fast electronically. My work developing Mama Bear,
    which alters the phase response of pickups, slowing down various frequencies selectively, has really proved to me that the pickups are faster than the instruments we've come to understand. So while I agree that phase is a crucial issue, I don't agree that piezo pickups have an inherent problem due to capacitance.

    You may very well be sucessful at slowing everything down with your combination pickup systems, thus making them sound nice. But that very slowing down of the response defines phase shift. And that is found in spades in magnetic pickups and microphones.
  13. luknfur


    Jan 14, 2004
    It dawned me I'd never even been to your site before so had a look and it looks like pups/electronics in general are not sold seperately - nothing uncommon about that but thought I'd verify it since you seemed to imply the piezo's are "temporarily" unavailable seperately.
  14. Rick Turner

    Rick Turner

    Jul 14, 2004
    I have sold pickups in the past, and with my other company, D-TAR we make a lot of acoustic amplification products available. Check out www.d-tar.com

    Right now I can't sell the bass Reference Piezo system because I can barely make enough for my own instruments. That's likely to change in the future, and we're looking at some pretty exciting possibilities including USB interface for VST applications. My piezo ceramic pickups have incredibly low noise, so they're really great in modern studios, pro and home, that have tons of nasty electrical crap floating around in the air. Ever try to sit at a computer and record a bass with magnetic pickups? Nightmare. Solved in R&D. With piezo pickups that have the best signal to noise ratio that's probably ever been done. Yes, no ****! You couple extremely high output pickups to extremely low noise preamplification, and you've got it made.
  15. luknfur


    Jan 14, 2004
    Couldn't get response from clicking the quote so a different route.

    Anyway, appreciate the feedback Rick. I've never seen any of your pups for sale on the used market and I can't recall anybody asking as much in TB. Don't know why I've never really thought about it till the posts in this thread. But I remember you saying something about that Diamond shaped pup before.

    Good for everybody to know at any rate cause it sounds like there's some latitude in the mix and will have a look at that link.
  16. Rvl


    Dec 23, 2003
    Aomori Japan
    I like Rick Turner's basses
    Have tried many piezos and have owned 5
    Have one Turner now and another on order
    I might buy one of Dave251 basses in the future(but at present none of the designs appeal to me) and I especially like the curved back

    I love the quietness of Rick's stuff
    When running through the board people are always asking me to turn the bass on

    Piezos do react much faster than magnetic pickups
    Try running a RB4 through a chorus or envelope filter , the sounds are much more upfront and direct than using a Sadowsky or Fender or even EMG equipped basses.

    Was comparing the Turner to my Sadowsky and expected the piezo to be similar to the bridge pickup. It turned out that the piezo sounded like the neck pickup but with a much wider frequency range. Turner's piezo setup is much warmer than my old Buscarino.
  17. Rick Turner

    Rick Turner

    Jul 14, 2004
    Dave, I spent a bit of time today with Dave Gordon, a guy who works at Josephson Engineering, a local manufacturer of high end studio condenser mics. Among other things, they make the capsules for the Manley 1" tube mics, and David (yes, another "Dave") Josephson is the chairman of the AES committee on microphone standards. To say these guys understand capacitive sources is an understatement.

    Cutting to the chase: Electrical phase issues with piezo pickups are negligible IF the impedance of the buffer is adequate. The electrical phase issues are far overshadowed by mechanical phase issues...exactly what I've been saying for years now with regard to a) the tight coupling of pickups to strings which makes pickups have "better" phase response (really impulse response) than do acoustic instruments. Point source piezo pickups OR small diaphragm mics that act more like point sources ...and my reference individual string pickups are about as close to that as you can get, exhibit truly excellent group delay as can be measured with a FFT of the impulse response.

    You can not use the analogy of a capacitor in the circuit when talking about mics or piezo pickups as long as the electrical interface is correct. There is no delay to speak of of low frequencies making the highs come at you sooner than you'd like. If there were, people would absolutely hate large diaphragm mics...and they don't.

    So the whole issue here is not capacitance, it's impulse response, and the smaller the source, the better it will be.

    I'll try to get some waterfall charts of the impulse response of some of these pickups. That's where the rubber meets the road.

    I still come back to the whole issue of acoustic guitars having a significantly delayed high frequency response in the acoustic realm. The net effect you and I do agree upon, the slap in the face effect, but the reasoning behind it is very different. Yes, a UST sounds too fast, but it's not because the lows are slowed down by capacitance, it's because the highs are not slowed down by traveling through the wood. Our ears are accustomed to the phase response of acoustic guitars being all screwy, and with a piezo UST it's not what we're used to.

    Check into impulse response testing of pickup systems, and you'll be amazed at seeing what you hear.
  18. Techmonkey


    Sep 4, 2004
    Wales, UK
    Hmm, I'm building a 5 string for my D&T exam, and I thought about having a tuner built in to the bass. I'll be using two passive Kent Armstrong pickups, but I was thinking about having a piezo system too. I was thinking about having a 3 way switch for the piezo/tuner system...:
    1: 9v battery supplying tuner
    2: Off
    3: 9v battery supplying Z matching circuit (posted in another piezo thread)

    Would this work? I was thinking then of having a blend between the SD pickups and the piezos. I'm not sure whether the piezos on their own would be enough to drive the tuner...
  19. Rick Turner

    Rick Turner

    Jul 14, 2004
    It's doable, but I don't get the logic.
  20. Techmonkey


    Sep 4, 2004
    Wales, UK
    Well I thought that having a tuner in the main circuit would give unwanted distortion? So creating another circuit with another set of pickups controllable separately would mean I could have the tuner connected to the bass without affecting the tone coming from the soapbars.