Using a guitar piezo?

Discussion in 'Amps, Mics & Pickups [DB]' started by josiah goldfish, Nov 22, 2012.


  1. josiah goldfish

    josiah goldfish

    Joined:
    Jan 10, 2012
    Location:
    E.Sussex UK
    Hey guys,
    My teacher is also a guitar player, and he says that he has a guitar piezo that I can buy off him cheap to use on my double bass. It's one of those moveable piezos that you blu-tak in place once you found the sweet spot. If i stuck it under the bridge foot or in the bridge wing, and plugged it into a bass preamp, could I use it as a pickup? Is there any difference between guitar and bass piezos?
    Cheers,
    Joe
  2. jeffbonny

    jeffbonny _____________ Gold Supporting Member

    Joined:
    Nov 20, 2000
    Location:
    Vancouver, BC
    A piezo is a piezo. Note though that stick on body pickups have never been popular with bass players. It will make your bass louder through an amp but chances it won't sound very good. If he's talking $10 or $20 go for it, you have to start somewhere. If he wants $40 or $50 you'd be better of with a used Underwood.
  3. Steve Dallman

    Steve Dallman Supporting Member

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    Mar 5, 2006
    Location:
    East Central Wisconsin
    My favorite location for a piezo is on the back, right where the soundpost hits the back. No string noise or that papery noise. It does require judicious cutting of bass though...an Fdeck would be perfect, although I've used a small series cap after the piezo. Radio Shacks cheap piezo (used to be $1.49...but higher now) taken out of the plastic case works well.
  4. Adagio

    Adagio

    Joined:
    Jul 21, 2011
    Location:
    Quebec City
    That could work yes. Depending on the type of piezo you might have to experiment with different locations on the bass. I'm using a guitar soundboard transducer that sounds great, a tad more midrangy than other piezos I've tried but it's a great alternative to other high end bass specific PU. You can read more about it @ http://www.talkbass.com/forum/f4/diy-pickup-experiment-826719/
  5. josiah goldfish

    josiah goldfish

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    Jan 10, 2012
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    E.Sussex UK
    So would it be better than or as good as the k&k hot spot or shadow sh sb1? I can only really order from thomann (I'm in the uk) and jab a budget of about £20. I haven't got a preamp yet but either of the pickups are available cheap and so's the guitar one. I suppose with the guitar one I could try it to see what it's like?
  6. jeffbonny

    jeffbonny _____________ Gold Supporting Member

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    You have to try it to know. Something you'll find as you use different pickups on double basses is that what works well on one instrument sounds terrible on another. If your teacher let you try his before you buy it I'd do that first.

    Steve Dallman has good advice about low cost buffering with a capacitor if a preamp is outside your budget right now. I've never tried this and am curious as to the range of values that he found worked best. Going this route might teach you a lot more about amplification than dropping several hundred on a state of the art pickup and preamp.
  7. iiipopes

    iiipopes

    Joined:
    May 4, 2009
    Or Fishman Full Circle.

    A peizo will need a buffer amp of some sort, like an fdeck, to match the very high impedance of the pickup to the relatively low (by comparison) impedance of most amplifier inputs, unless the amplifier has a dedicated piezo input.
  8. Steve Dallman

    Steve Dallman Supporting Member

    Joined:
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    Location:
    East Central Wisconsin
    I got the idea of putting a piezo on the back of a stringed instrument after reading about a 70's ELP tour, where they toured with the London Philharmonic and were faced with how to amplify the many strings in the orchestra. Mics were too feedback prone and bled too much.

    So they put Barcus Berry pickups (the early, little rectangular piezos) on the BACKS where the soundpost hit the back. The energy from the strings, and the bridge are focused there, and there was no noise from fingers or bows. Orchestra players were reluctant to stick ANYTHING on their expensive instruments, and indeed there was some damage.

    I experimented on my upright, and found the back to be the most natural and un-pickup like tone. I laid down some Scotch 33 electrical tape to protect the finish (it always came off clean with no residue or damage) used putty to mount the thin piezo (using the 1" Radio Shack piezo element) and ran the thin cord I had soldered onto the piezo down the back of the bass, and up to the tailpiece, where I had put a jack.

    A piezo does need a high impedance input, typically 4.7meg ohms to 10 meg ohms. Going into lower impedances restricts the volume and low end of a piezo. This may be desirable. In the case of K&K pickups, they recommend 1meg. Going into 10meg will cause too much low end. On a bass, restricting the very low end would likely be beneficial.

    I plugged my upright into a standard 1meg input bass amp. My bass was smaller, 1/2 size, so low end wasn't as great acoustically. I put one on a 3/4 sized bass, and I believe I used a .001uF cap, but this was in the 80's, and my memory is not good enough to remember details of all the work I did back then.

    I was never able to get the tone I wanted out of mounting piezos on the bridge, and I tried many variations, but no commercially available pickups. I did quite a few basses and violins back in the day.
  9. Steve Dallman

    Steve Dallman Supporting Member

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    The physical area of a piezo makes a difference. K&K uses fairly small piezos, but uses two or more. The 1" one from RS has quite a bit of low end, because of the area. Tone of any will vary depending on the input impedance plugged into. The benefit of using a buffer or preamp is that from the buffer/preamp on, the tone will be consistent coming from the instrument, regardless of what you plug into.
  10. Ric Vice

    Ric Vice Gold Supporting Member

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    Jul 2, 2005
    Location:
    Olivette, Missouri
    Joe,
    There are pickups where different versions look similar. One that comes to mind is the Realist for Double Bass, and the Realist for Cello. However, in most of the examples I can remember, the size of transducer for Bass is always much larger. With more surface contact area. While the guitar pickup may work, my guess is that it won't sound as good as a DB specific pickup. I remember well the Barcus Berry silver bar pickup that Steve mentioned above, it sounded awful even with Barcus Berry's little accompanying preamp. I truly believe that the reason it sounded that way because the element was to small to reproduce the sound of a Double Bass.

    Cheers

    Ric
  11. josiah goldfish

    josiah goldfish

    Joined:
    Jan 10, 2012
    Location:
    E.Sussex UK
    Thanks for the replies everyone, I'll try the guitar piezo and see how it sounds.

    Maybe a better question would be, what's the best top three pickup + preamp combinations under £100? I can buy both seperately, but if a pickup doesn't need the preamp that's even better. Does the revolution solo need a preamp?

    Cheers
    Joe
  12. DoubleMIDI

    DoubleMIDI

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    Feb 28, 2010
    Location:
    Germany, Nordrhein-Westfalen
    It depends on your amplifier. If you use diferent amplifiers or amplifiers you don't know (like in a practice room or the one that already sits on the stage) you want to have a high impedance preamp to get the best sound out of the amp.
    I doubt that you can get a preamp and a pickup together for £100 new. Maybe used but even this will be hard to get at all.
    The cheapest solution I know which is and good for bowing is the Shadow SH 965 NFX, which has a impedance buffer (this is the important part for a piezo pickup) built-in. You can get it from Thomann in Germany, but it will be more expensive than your budget allows.
    You can also try to get a FDeck HPFpre I or II in the US if you have contacts there to forward it to the UK. But with a bridge wing pickup, it won't become cheaper than the Shadow. You can experiment with piezo disks, which are cheap, but my results (I tried them several weeks) doesn't give a strong signal (the sound was good but the signal too weak). Even for a good preamp alone (like the Headway), you have to invest more than twice your budget and then you still need a pickup.

    If your amp has an input impedance of at least 1 MegOhms, you might buy the pickup first and a preamp later (or build your impedance buffer yourself: the FDeck Quick'n'Dirty is easy to build and very good).

    I think you need to check your budget and preferences again.

    You can get a cheap bridge wing pickup from a member of the german double bass forum www.geba-online.de.
    Check the following link:
    http://www.geba-online.de/katalogsuche_quick-12-29_Ueber-GEBA-Shop-kaufen
    You will find a cheap, but good bridge wing pickup (one or both sides) there.
    I don't know if they deliver to the UK, but you can ask.
  13. jeffbonny

    jeffbonny _____________ Gold Supporting Member

    Joined:
    Nov 20, 2000
    Location:
    Vancouver, BC
    An often overlooked buffering preamp option is the Boss GEB-7 Bass EQ pedal. It's got an input impedance of 1 M ohms, a reasonably well voiced EQ and used they go for $40-$60 US.
  14. DoubleMIDI

    DoubleMIDI

    Joined:
    Feb 28, 2010
    Location:
    Germany, Nordrhein-Westfalen
    Yes, good point with the Boss efffects. They all seem to have this input impedance.
    But 1 MegOhms is not enough for optimal sound of piezo disks (Fishman BP100 and most homemade pickups). It is OK for the piezo foil (Realist) and bridge wing pickups (Underwood).

    At the moment somebody in Cologne sells his Shadow SH 965 NFX used for 115 Euro, which is close to the budget:
    http://www.geba-online.de/12-8857-Shadow-965-Nanoflex-Kontrabass
    I'm not sure if this has already gone or not.
  15. StereoPlayer

    StereoPlayer

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    Saginaw, MI

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