Summit Audio TD-100 Instrument Preamp and Tube Direct Box

We now own five of these, and have used them successfully for years. Why we own them and where they really shine for us is with instruments which have passive pickups.Acoustic basses, for some reason, nearly always have a passive pickup and invariably their direct signal is not at all pleasing without massive amounts of EQ, often not producing completely satisfactory results. Especially when played on stage in a jazz setting, a microphone on bass is usually not satisfactory by itself because of the bass' proximity to drums and the resulting high level of drums in the bass mic.The variable impedance knob on the front of this DI allows us to greatly improve the tone of an acoustic/jazz bass. The difference is stunning. Furthermore, because the tone is improved through the matching of impedances (don't worry, you don't need to measure anything -- just turn the knob and listen), the result is much more natural and less "processed" sounding than through the use of EQ. Interestingly, the setting is usually different for each instrument/player. If needed, EQ can then be used to further tailor and sculpt the tone -- something for which it is much better suited.I am a recording/sound reinforcement engineer, and for me this box is a must have. I don't understand why every bass player doesn't own one, though I've yet to meet one who does. The sound coming into their amp when passed through this box is also vastly improved, and so the amp settings which they can use are much more subtle and the results much better.In our work, a Summit Audio TD-100 DI and a DPA 4099 mic with bass clip are used in tandem on countless live jazz performances. We love the results, and I can highly recommend this device.(My only complaint, and there's no obvious solution: Don't forget that there is glass (vacuum tube) inside the device -- handle it with care, or have a spare to use while one is off for service!)