Intro
The Behringer TM300 Tube Amp Modeler is the poor man's SansAmp GT2. Literally, the TM300 is a feature-per-feature replica of the Tech 21 SansAmp GT2, but wrapped in a blue, Boss-like enclosure. It provides miked amp tone, and is used most often in place of an actual amp. I use mine toward the very beginning of my "candy store" pedalboard (which I will also blog about).
Caveat emptor: Behringer clearly ripped off Tech 21 with this one. If you have the cash, just buy the SansAmp GT2, since it is better in every way: signal processing, sound, and build. I will eventually replace my TM300s with the GT2.
Build
Materials-wise, the TM300 is no Sans Amp. For starters, It is shaped more like a Boss pedal, and it is housed in tough plastic casing instead of metal. Compared to Boss pedals, It feels sophomoric. However, for the price--around US$25--it is a steal. And, frankly, the type of plastic seems to be optimal for this and Behringer's similar pedals. I would tour with the TM300 if it was protected in a road-ready pedalboard, though I would probably pack a spare TM300. Used normally, I think this will hold up well.
The knobs of this and most Behringer pedals turn very firmly, which adds a sense of heft or solidness when making adjustments. Otherwise, the underlying potentiometers have a little bit of "give" or wiggle from side to side, which is the only aspect I found a bit flimsy-feeling.
Like Boss pedals, the battery compartment is the inside hollow directly below the physical pedal mechanism. However, unlike Boss pedals, the compartment is tricky to access. I prefer using power rather than batteries, so I've never installed/replaced batteries in any of my Behringer pedals, but I have read several comments related to this issue. (Suggestion: buy a Boss PS-120S power supply, plus a 3-, 5-, or 10-pedal daisy chain connector to power many pedals from a single power supply.)
Sound
The TM300 produces usable, recordable amp modeling. The models are convincingly warm and tube-like, if not superbly detailed. I have no qualms using the TM300 live as a virtual amp combo. Setting the LEVEL, LOW, and HIGH knobs to "12 o'clock" and the DRIVE knob counter-clockwise to its lowest setting provides the best "base" from which to experiment with the major features of the TM300. (You can see from the picture above that I've settled on a clean, open tone, which I drive with a BOSS DA-2 Adaptive Distortion when I need high-quality grit.)
From there, setting the MIC, MOD, and AMP switches to their leftmost positions (CLSIC, CLN, and TWEED, respectively) provides an open, midrangey, ostensibly distance-miked clean tweed combo sound, minus any room ambience. Moving the MIC switch to its middle position (CNTR) emulates the sound of the same tweed combo with the mic positioned very near and at the center of the speaker. Moving the MIC switch to its rightmost position (OFF X or "off-axis") represents the same close-miked tweed combo, but with the mic positioned at the edge of the speaker. I prefer the OFF X setting.
The MOD switch represents preamp gain stages: CLN (clean), HI G (hi-gain), and HOT. As expected, CLN provides a clean, non-overdriven tone. Adjusting the DRIVE knob clockwise increases compression and adds a slight amount of overdrive bite, though the sound never quite moves beyond the realm of "clean", even when DRIVE is at its highest setting. The MOD/HI G setting starts with a mild to medium overdriven preamp tone when the DRIVE knob is at its lowest setting. Moving the DRIVE knob clockwise increases the overdrive and compression to mimic an hi-gain, cranked amp tone, which works well for classic and hard Rock. The MOD/HOT setting with the DRIVE knob at its lowest level provides a saturated, mid-scooped tone. Turning the DRIVE knob clockwise increases the saturation. Adjusting the DRIVE clockwise to its highest setting creates a very dense and intense distorted tone great for Metal.
The AMP switch provides amp variety: TWEED (Fender), BRIT (Marshall), and CALIF (Mesa Boogie). The Behringer product page (http://www.behringer.com/EN/Products/TM300.aspx) is somewhat sparse, description-wise. I recommend visiting Tech 21's GT2 product page (http://tech21nyc.com/products/sansamp/gt2.html), where not only will you find a complete description, but also see how thoroughly Behringer ripped off Tech 21.
Conclusion
The Behringer TM300 Tube Amp Modeler has no competition in its price range. It is an absolute steal at US$25. It functions as advertised, and it is "good enough" for the pedalboard in which I use it currently. Actually, I love this little gem. For many, like me, it can serve as a stepping stone to a SansAmp GT2 when money allows, and afterward as a backup or as a gift.