The best sound is a microphone and good mic technique. Period, end of story, no question asked.
That being said, almost no one has mic technique that good while on stage. For most people, the first step towards getting a good sound on stage is, indeed, piezo pickup with a preamp. There are a number of versions of this. The first company to offer the internal preamp option was Highlander, which was designed by Rick Turner and Bob Wolstein. It is still a very popular choice, and they sound very good. The downside of the Highlander is the actual pickup. It is a length of coaxial piezo cable, which was originally designed to help military submarine sonar operators hear in the "blind" spot behind the propellers (or “screws"). It would be trailed behind the subs, and would pickup vibrations in the water. The problem with this is that, the cable is round. Installing them correctly requires that you rout the bottom of the saddle slot to match the round profile of the pickup, and it is recommended that you also have a concave bottom of the saddle. This is, obviously, time consuming and expensive to install.
Fishman is the industry leader in piezo pickup industry, and for good reason. They make a very solid product. The other reason they in such a dominant position is that they make all of the pickups used by Martin, Gibson, and all Taylors with pickups in the 400 series and under. This is, needless to say, a great boon to their business, and to their marketing department. I have a Fishman in the one guitar I own with a pickup in it, until recently it was the one I liked the most, and is half of the system I would use if I was playing out a lot. They have two basic models, the Matrix Natural I, and the Matrix Natural II. The Natural I is a (mostly) flat preamp, which will (generally) sound better, and is intended as an all purpose pickup, good for all kinds of situations. The Natural II preamp has a dip in the EQ which is intended to cut back on feedback when playing in a louder situation, such as a band. It is also designed to cut through the noise in a band situation. My preference is to use the Natural I for all situations, because I can find the resonant frequencies myself and make the necessary cuts with a good parametric EQ. As a live sound engineer, I would rather an artist had the Natural I, as it gives me more control (it is easier to remove than to add). The main advantage of the Matrix, and the reason it is still the one I recommend above all others, is the ease of installation (relative term, it should still be done professionally). For us, our installation of the Fishman is about $75-100, and the Highlander is in the $100-150 range. The Fishman system is also slightly cheaper, at least we sell it for a little less than our friends in town who sell the Highlander. Total installed cost for the Fishman at our shop is $200-$225. The Matrix systems are also intended as the base unit for the Fishman Blender system, and can be upgraded with ease, though for a rather high cost.
As I said earlier, I used to like the sound of the Fishman best, and I do still like the system. However, there is a new system out, made by a company called D-Tar, which is co-owned by Rick Turner and Seymour Duncan. Their entry into the piezo/preamp category is called the Timbre Line. The idea behind it was that the Highlander and the Fishman were underpowered with only one nine volt battery. They both (the Highlander and the Fishman) have fairly harsh high ends. Rick's thought was that the nine volt systems where distorting the upper harmonics, so he designed the Timbre Line preamp to work at eighteen volts, using two nine volt batteries. This gives the Timbre Line much greater headroom, which minimizes this distortion. Shortly after they introduced the Timbre Line, Rick sent us (and a number of other prominent luthiers) a free Timbre Line to try out. We installed it in one of our guitars which was hanging on the wall as a way of trying it out. My impressions were that the Timbre Line is a little brighter than the Fishman or the Highlander, but without the high end harshness of those two systems. I am quite fond of the sound of the Timbre Line. These days, it is half of that system I mentioned which I would use if I played out a lot more. The major disadvantage with the Timbre Line is the same as with the Highlander, which is the pickup element itself. It is the same (or same type) coaxial piezo cable as is used for the Highlander, which means it has the correspondingly higher installation cost. It is a matter of opinion whether the slightly improved sound (and it is SLIGHTLY) is worth the additional cost. We are selling the Timbre Line for about $15.00 more than the Fishman, and installation of about $100-150, like with the Highlander. If I was putting another pickup in one of my guitars, I would use a Timbre Line. They also have many new developments coming up, which they are consulting with other builders on, but which I do not feel comfortable talking about yet. I will just say that, within the year, I may not be recommending the Fishman as much as I have been up to this point.
There are other undersaddle pickups out there, but I would suggest you stick to the three I have mentioned, as they are (in my mind) the best. There are of course other styles of pickups. In the same family, but of a different species from the undersaddle systems above is
the L.R. Baggs iBeam, which is available in both active and passive versions. They are a piezo system, but they do not use an under the saddle pickup. Instead, they use a pickup which is imbedded in a block of some composite material, which attaches to the underside of the bridge plate. They sound quite nice, but they are prone to feedback, as the pickup is not under pressure (which makes a big difference in feedback elimination). As with all professional pickups however, the iBeam does require professional installation, though it is usually less than with a Fishman system (though the pickup itself is more expensive).
The other major type of acoustic pickups are the magnetic pickups. These are, in essence, electric guitar pickups designed to sound more like an acoustic pickup. They do not sound as acoustic as undersaddle pickups, but some of them are very good. The best magnetic pickup by far is the Sunrise. They have been around for probably fifteen years, and they are still the best. If you want to recreate the Leo Kottke sound, you need to practice a lot more, but then you want to install a Sunrise. This is also the pickup Lyle Lovett uses. If I was playing out a lot, this is the other half of the system I would use. The Sunrise is an excellent pickup, and is a very high end piece of equipment. You will not find a better product for its type.
Fishman also makes a Magnetic pickup, called the Rare Earth. They are also very nice pickups. They sound a little more electric than the Sunrise to my ear, but they are still very nice. They are also smaller and lighter than the Sunrise, which some people will like.
Finally, there are the combination systems. The most popular of these is the Fishman Blender. This combines they Matrix undersaddle pickup/preamp system with a small Crown microphone, which clips onto one of the braces. This system is very popular for players who are usually the primary focus when they play. The best know person using one that I am personally familiar with is Pat Donahue, who plays on A Prairie Home Companion every week. There are, of course, many others who use these systems, and there are others who make these systems. The L.R. Baggs Dual Source is a similar type of system, but the piezo elements in them is even worse to install than the Highlander, and I don't think they sound as good as the Fishman. Fishman also makes a Blender system for the Rare Earth systems. I have no experience with these systems, so I will not comment.
Finally, there is the possibility of putting together a combination system of your own. This, as you may have noticed, is what I would do if I had any need for it at all. I rarely play out, so I feel no need for this system, but if I did, I would take my hints from Michael Hedges. He used an old style of piezo crystal pickup made by Barcus Berry (I believe), which used three piezo crystals stuck to the inside of the top. In addition to this, he used a Sunrise. The combination of the two provides an interesting mix. The Sunrise definitely has a better low end, and it responds much better to the tapping for which Hedges was so well known. The piezo pickups do a much better with the high end, and can also pickup the thumps, slaps, and bangs on the body for which he was also known. I like this combination a lot, and if I was to start playing out a lot, I would use the same ideas, but I would be doing it with a Sunrise and a D-TAR Timbre Line.
What I would probably recommend for you, though, is that you start out with a Fishman Matrix Natural I. If you are still unhappy with the sound, step up to the blender system, with the microphone. I would highly recommend, however, that you start out by trying it without the microphone, as it is the right system for probably 90 percent of the players out there.
So that is a long answer to your question, but it is most of what I know. I hope it helps.
Light
"Cowards can never be moral."
M.K. Gandhi
