Top mounted transducer on an acoustic?

As in a stick-on or glue-on piezo?

Just my opinion: They are good for a quick installation and reasonable results for live playing if you and your audience aren't too picky. Not the best for recording unless combined with a mic, other soundhole pup or a matrix of piezos. If choosing a single pup, I much prefer a magnetic soundhole pup to a piezo, even in the less expensive price ranges. Under-the-bridge (or bridgeplate-mounted) piezos can provide a better tonal balance than a stick-on piezo, but are far more difficult to install. Even then, I still prefer the mag soundhole pup (and recommend Fishman Rare Earth models, FWIW).

All that said, a top-mounted piezo is an inexpensive and easy way to start experimenting with acoustic amplification. Given a modest bit of soldering and electrical talent, it's actually pretty easy to build a stick-on piezo from certain models of piezo buzzers sold by Radio Shack. Here's a link: http://web.mit.edu/kumpf/www/Acoustics/main.html

BTW, no matter what you decide to build or buy and use, an acoustic pup equalizer improves the tone of every type of pup -- and you can always add one later on.

Thanks gnease, your insights are very helpful. The transducer that I was considering is a stick-on and all I really wanted to do with it for now is just play at home and practice, no recording. I've seen the do-it-yourself site before and thought about doing it to my old yamaha FG170, whick I might still do. The transducer I was looking at is inexpensive - under $20.00, I found it on the Grizzley Industrial tool site of all places. They sell a lot of Asian manufactured tools, but they also have a luthiers section that has kits, parts and materials. I thought it was a real unique combination.

One question that I thought of, would an equalizer pedal work in place of an acoustic pup equalizer?

Thanks.

A pedal EQ certainly seems worth a try, especially if you already own one -- definitely better than not having one.

An acoustic pup-specific EQ ...
*may have different cross-over points to esp facilitate more high frequency tailoring
*can be a parametric instead of graphic EQ
*have an input stage designed for a piezo's loading and level characteristics
*be equipped with an narrow, adjustable notch filter that can be used to reduce feedback

If you are using a $20 pup, you probably would not want to spring for an acoustic EQ, so try the pedal route.

Thanks gnease, I'm probably going to go down the cheap route. You mentioned the one main concern that I had which is load matching the transducer's output with the pedal/amp's input. Hopefully it won't be a major issue, if it becomes one at all.