EQ for piezo pickup?

[Steve Ostrander]

I tried piezos with a Baggs Gig Pro preamp. It just sounds too shrill and unatural to me. I went back to using an SM57.

Maybe there is a piezo that has a natural sound, but I've tried three and none had it.

[Mark Normand]

Originally Posted by Steve Ostrander

I tried piezos with a Baggs Gig Pro preamp. It just sounds too shrill and unatural to me. I went back to using an SM57.

Maybe there is a piezo that has a natural sound, but I've tried three and none had it.

I was just about to post a question about this Gigpro preamp.

I'm so very uninformed with this stuff. Right now playing out a bunch with a Gibson Flatiron Festival, with an internal piezo with double pickups. Cost was about $110 installed, and I honestly don't remember what brand .
Mostly restaurant gigs with me, guitar, and doghouse bass.

I have a Yam Stagepas 300 system, and plug in the mando direct, along with guitar, and two Shure vocal mics. The bass has his own amp and DI box. We get by, but....

Do I need a DI box of some kind with at least basic EQ? Is that a safe bet? Rather not buy the $150 Baggs DI box just yet, are the $50+ types better than nothing? Fishman G-II, Baggs Gigpro, etc. ??

Thx gang.....

ps the Yam specs are here..
http://www.yamaha.com/yamahavgn/CDA/...ml?CNTID=36692

[Matt DeBlass]

OK, I just solved my problem with a trip to the storage unit. I had won a Crate CR-1 tube amp in a contest years ago, when I worked at a guitar store. I don't really play electric, so I didn't really use it, but it was a special edition (only 50 made) so I didn't want to get rid of it. But I'd forgotten about it.

The long and the short of it is that I tried running my piezo-pickuped mandolin through the amp and messing around a bit with the gain and tone knobs, and ended up with a very nice, warm amplified tone. It's not "Bluegrass" but it will work well for celtic and folk, I think (and with a bit of a tweak to the gain, a little rock n' roll).

[pops1]

Usable sound from a piezo can be achieved if you run into a tube amp. It will be better however at a lower volume.

[Tim Bowen]

For what it's worth, I've gigged a variety of acoustic-electric instruments on a weekly basis as DI'ed through a PA for at least the last ten years. Bars to clubs to outdoor festivals to concert venues. From Podunk, Alabama to Nashville, Tennessee. Acoustic-electric standard, twelve, and high-string guitars (piezos and hybrid systems), electric lap steels with humbuckers and single coils, mandolins, electric banjo, electric sitar, whatnots.

I own lots of boosters and preamps, including the Baggs. It's great for fine tuning to a specific instrument, but it's not as predictable and intuitive on the fly over a variety of rooms and situations and instruments as I'd like, in my opinion and experience. Furthermore, it doesn't contain a stomp that can bypass the dialed tone, which is a deal breaker for me.

I'll sound like a stuck record here, but the single most useful and predictable and simple boost/pre that I've found for a variety of acoustic-electric work has been the Xotic RC boost. Small box format, excellent headroom, about $175.00 as new. Knobs for pre-gain, post-gain, bass, and treble. Honestly, that's all you need for acoustic-electric PA/DI performance scenarios. The one instrument where specific mids contour matters to me is a twelve string acoustic-electric guitar. Other than that, I rarely give the first thought toward mids. Sonically, acoustic-electric eight string mandolin is easy pickin's in the live enviroment. It wants loads of headroom, a loud and clear signal, and minimal presentation of midrange and compression character. That's pretty much it, at least in my humble opinion.

[Tim2723]

You can also just get an Ovation for the times you need to be amped. Solves a lot of problems.

[jim_n_virginia]

Originally Posted by mikebrennan

i'm a transducer design engineer for a company that manufacturers piezo. You can take my advise or not, but i know what i'm talking about.

The advice given earlier about impedance mismatch is correct, although it's usually not a problem. Piezo is considered ultra-high impedance, with output impedances on the order of megohms. What that means is that while it can put out reasonable voltages, it can furnish little charge, or current. Therefore any capacitance in the chain will load the output. However, earlier advice stating that this reduces the bass and makes the highs zingy is wrong. In fact, it's just the opposite. Cable capacitance will reduce the highs, so piezo pickups can sometimes benefit from long cables. It works exactly the same way the passive tone control works on an electric guitar. By introducing parallel capacitance you create a low pass filter. The question is whether the pickup output is enough to get a reasonable signal to the input of the amplifier or pa. If not you need what is called a buffer amplifier. A buffer amp is a preamp used for correcting impedance mismatch. It will "see" the output from the pickup at it's input, and duplicate that signal on it's output, but it is capable of as much charge, or current, as required, so cable capacitance is not an issue after the buffer.

The last thing to consider then is the eq. It is said that piezo pickups sound "harsh" with too much high end. While this is true, it's not really a shortcoming of piezo. Rather, it's the result of decades of development of sound equipment geared toward microphones with voice coils and electric guitar pickups with inductive coils. Amplifiers have been developed to work with these devices which have lower output in the treble frequencies. Consequently pa's and amplifiers boost the highs. Piezo doesn't need the highs boosted. So to work with modern sound equipment piezo pickups need eq to reduce the highs and boost the lows.

The passive filter created by using long cables will attenuate highs at a rate of 6 db per octave. If that doesn't take enough of the highs out for you then you need an active eq.

My method is the dod graphic eq i mentioned in an earlier post. There is no problem whatsoever with using an electric guitar effect pedal for piezo. It acts as the buffer amp and provides eq controls. It works great, and cost about $30 used. I set the 8 sliders in a straight line, high in the bass end, and gradually getting lower as you move toward treble end where it's all the way down. I get a great sound.

Mike brennan

good info mike thanks!!!