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Topic: piezo pick up way to bright ???? |
Dennis Brown
From:
Gowen, Mi. USA
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Posted 25 May 2009 5:28 am |
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| I'm using a piezo pick up on a dobro and it's way to bright. Is there something out there I can install in line that would help? Bass all the way up and treble all the way down on my peavey 400 ltd and still way to bright. I also tried relocating the piezo on the bass side of the guitar. This piezo has lots of volume, thats one reason I wish to use it. Thank you in advance, Dennis Brown |
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Howard Parker
From:
Maryland
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Posted 25 May 2009 5:36 am
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Part of the problem is that the amp is not voiced for acoustic instruments.
You don't mention which pickup you are using. Some have better characteristics than others.
More info...Please.
_________________
Howard Parker
03\' Carter D-10
70\'s Dekley D-10
52\' Fender Custom
Many guitars by Paul Beard
Listowner Resoguit-L |
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Donny Hinson
From:
Glen Burnie, Md. U.S.A.
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Posted 25 May 2009 5:55 am
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| What type of preamp are you using? |
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Dennis Brown
From:
Gowen, Mi. USA
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Posted 25 May 2009 6:00 am piezo?
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| Donny Hinson wrote: |
| What type of preamp are you using? |
Hello Don, I'm going direct to amp. No preamp. Dennis |
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Howard Parker
From:
Maryland
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Posted 25 May 2009 6:05 am
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Dennis emailed me. I hope he'll continue the discussion here.
He is using a piezo element from a Radio Shack buzzer. There is no telling what the impedance/output characteristics are.
I don't think there is a reasonable way to predict how this element is going to react in this application. A good acoustic preamp may help, or it could be just a waste of money.
Fun experiment though.
_________________
Howard Parker
03\' Carter D-10
70\'s Dekley D-10
52\' Fender Custom
Many guitars by Paul Beard
Listowner Resoguit-L |
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Dennis Brown
From:
Gowen, Mi. USA
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Posted 25 May 2009 6:24 am
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| Howard Parker wrote: |
Dennis emailed me. I hope he'll continue the discussion here.
He is using a piezo element from a Radio Shack buzzer. There is no telling what the impedance/output characteristics are.
I don't think there is a reasonable way to predict how this element is going to react in this application. A good acoustic preamp may help, or it could be just a waste of money.
Fun experiment though. |
Thanks for hanging in there Howard. The piezo buzzers from radio shack are less than $2.00 each. They are about the size of a quarter. here are some specs. voltage range-3.0-20vdc. rated votage-12vdc. 2.7khz. 10mA 2700+/-500Hz resonant frequency. I hope this will help because I don't have a clue what all this will mean. Thanks everyone, Dennis |
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Brad Sarno
From:
St. Louis, MO USA
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Posted 25 May 2009 6:41 am
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Different piezos will have different resonances. Many piezo instrument pickups will not only be the raw piezo element like you have there, but also some degree of mass and/or dampening behind it to help tune the resonance and bring out some fullness. I used to mess with those Radio Shack type elements. You may want to try and glue a penny or small washer to the back and cover that area, along with the penny (or washer), in goopy glue.
Without any pickup dampening, it makes sense that you'd be getting a lot of treble without much bass response. You can also try adhesive putty to mount the surface. The putty can also be used in various thicknesses to help dampen highs. This may work.
You should be able to get your amp to voice ok. Most acoustic preamps simply need the one sweepable midrange dip to control the instrument's main feedback resonance, and then some basic bass, mid, treble, and hi-treble (presence). The Peavey should actually do quite well as an acoustic preamp as it's nearly identical electronically to many common acoustic preamps.
The only problem I see here is that the input impedance to the Peavey is low, I think around 330k or so. Piezo's lose their bass response as the impedance goes down. That's why many acoustic preamps have 1M or much higher input impedances. This assures the most low end response from the pickup. So if you have some sort of impedance matcher, or even a Hilton volume pedal, this may help a lot.
Best,
Brad |
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Dennis Brown
From:
Gowen, Mi. USA
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Posted 25 May 2009 6:55 am Piezo?
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| Thanks a bunch Brad. I have the adhesive putty on it now, it's not enough. Is there something I can install in line (tone capacitor)? Seems to me I had one installed on a volume pedal along with a foot switch years ago. Thanks again you have been very helpful. Dennis |
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Michael Maddex
From:
Northern New Mexico, USA
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Posted 25 May 2009 1:58 pm
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Dennis, you could try a capacitor across the piezo element to bleed some of the highs to ground. I would try a value of .001 or .0047 μF to start. You can find some at Radio Shack if you don't have any lying around.
HTH.
_________________
"For every expert, there is an equal and opposite expert." -- Arthur C. Clarke |
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Pit Lenz
From:
Cologne, Germany
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Posted 25 May 2009 2:16 pm
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Hi Dennis,
as Brad also mentioned before, this sounds like an Input impedance mismatch to me.
I did the same thing with my ukulele, got me some cheap buzzer elements, glued them to a coin and taped them under the bridge of my uke.
The sound was bright and thin.
Then I tried a L.R.Baggs paraD.I. and voila: the sound got much rounder and fuller then.
Piezo elements have a very high impedance.
In order to match that, you´ll need a preamp with a fairly high input impedance, too (the ParaD.I. has 10 Meg.Ohms, the 400 LTD has 330 KiloOhms).
There are many manufacturers building hi-Z preamps.
Two popular ones among others are Baggs and Fishman.
Try to find one in a store, plug in and find out yourself...
Here´s another article about that.
Hope that helps.
greetings
pit |
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Bryan Bradfield
From:
Lethbridge, Alberta, Canada.
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Posted 25 May 2009 4:06 pm
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I also installed Radio Shack piezo elements in a variety of acoustic instruments several years ago. A Fishman Pro-EQ pre-amp solved the high frequency problem. I assumed it would, as the Fisman company pioneered in the use of piezo elements, as I understood. I therefore assumed that the buffering in their pre-amps would be suitable for piezo elements.
Last edited by Bryan Bradfield on 25 May 2009 4:08 pm; edited 1 time in total |
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Dennis Brown
From:
Gowen, Mi. USA
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Posted 25 May 2009 4:08 pm Piezo?
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 Thanks everyone. Now I got avenues to take on my adventure. You all been great, Thanks again. Dennis  |
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