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Summit Audio TD-100 Tube Instrument Preamp & DI Box - Used  From Summit

Tube DI Box


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Summit Audio

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What We Think

A wonderful sounding, spectacular performing little tube DI. Never underestimate the power of a continuously variable impedance control... It allows to truly pinpoint the input of your keyboard, bass, guitar, or other instrument for truly optimal settings, enabling an impedance match more ideal than pretty much any other DI on the market. You can't beat the price, and the versatility is definitely there on this one. Due to being a tube design, this box isn't as detailed and accurate as Di's such as the Avalon U5, but nevertheless, the tube warmth and obvious impedance control advantages make this little di an excellent choice to add to your arsenal.

Manufacturer's Description from Summit

The new TD-100 instrument preamp and tube direct box from Summit Audio features a hybrid signal path utilizing both a discrete solid state output device and a 12AX7A/ECC83 vacuum tube to give your musical instruments the clarity of class A sound with the richness and warmth of vacuum tubes all in ? rack space. Perfect for both live and studio use, the TD-100 offers both XLR microphone level and ?" TRS line level outputs, plus variable input impedance, polarity switch and ground lift, signal and overdrive LEDs, and even a headphone output for use as a practice device. All with the quality that says Summit Audio. Typical uses for the TD-100 What is a direct box? The TD-100 is both a direct box and an instrument preamp. A direct box or "DI" (direct inject or direct input) is used to take high impedance instruments and transform them into a balanced, low impedance output. Most professional consoles need a balanced, low impedance input and a DI translates an instruments high impedance, unbalanced output for recording and mixing. Use the balanced XLR output on the TD-100 to send your instrument to the console or other preamplifier. For example: keyboard out -> TD-100 instrument input -> TD-100 XLR output -> console microphone input What is an instrument preamplifier? Use the ?" balanced TRS output on the TD-100 to go directly into your recording device (DAW, ADAT, tape machine, etc.). This output is already amplified, so there is no need to go to another preamp such as the microphone input on a console. This output is also useful for interfacing your instrument with compressors, EQ's, and other signal processors such as gates, expanders, filters, etc. For example: electric guitar out -> TD-100 instrument input -> TD-100 ?" output -> compressor input -> compressor output -> EQ input -> EQ output -> tape input What makes the TD-100 so special? Summit Audio designed the TD-100 with two things in mind: great sound and lots of versatility. All the features on the TD-100 enhance the sound of your instrument, helping you get the perfect tone for your recordings and shows. We have selected the best components, relying on our 20 years of experience making the highest quality signal processors to choose great sounding and long lasting inputs, outputs, potentiometers, switches, and other components, making the TD-100 a highly valuable, fantastic sounding, and long lasting tool for your music. How do you use the TD-100 live? The TD-100 is perfect for playing live. It is made to interface your instrument with the front-of-house and monitor sound consoles with either a low level (microphone) or high level (line) output. To insert the TD-100 between your instrument and your amp, just run your instrument into the TD-100 and run another ?" cable from the direct instrument output into you amplifier. Then, choose either the XLR mic level or ?" line level out to run into the snake or stage box to run to the front-of-house and monitor consoles. For example: acoustic guitar out -> TD-100 instrument input -> TD-100 XLR output -> XLR mic level input on stage box plus ?" direct instrument output into your amp on stage How do you use the TD-100 in a recording studio? Using the TD-100 in a recording studio will give your recordings a warm yet clear tone. By utilizing the ?" line level output, you can bypass any other preamplifying stage such as a console, thereby lowering the noise floor, and enabling you to run much longer cable runs without significant signal loss. If you need to monitor into the console at the same time, simply run the XLR output into the console and monitor from there while recording from the ?" TRS balanced output. For example: bass out -> TD-100 instrument input -> TD-100 ?" TRS balanced output -> compressor input -> compressor output -> DAW interface input How do you select the right input impedance? The impedance selector on the TD-100 front panel varies the amount of loading or impedance on the ?" instrument input. You can check the output impedance on your instrument by reading the instruments manual. Try moving the loading control until it sounds right; your ears will be the best judge. Note: the loading control does not affect the direct instrument output. How do you use the TD-100 as a practice headphone amp? Just plug your headphones into the ?" headphone output on the back of the TD-100 and your instrument into the input on the front and use the gain control and the volume control on your instrument to get the right volume level. How do you mount the TD-100? The TD-100 comes ready to mount in a standard rack shelf, such as the Raxxess UNS-1 or the Middle Atlantic UTRI. Simply use the supplied mounting screws to mount the TD-100 through the rack shelf. Please contact us if you need to find a source for a universal rack shelf. How and when should you change your tubes? The 12AX7A/ECC83 vacuum tube in the TD-100 should last as long as 10,000 hours or more before requiring replacement. The best idea is to let your ears tell you when it needs to be replaced. If it seems there is distortion or ringing in your signal, then the vacuum tube may need to be replaced. Contact your dealer to find out about replacement tubes and for a qualified service technician

Summit Audio

About Manufacturer

Hello and thank you for choosing Summit Audio! We have a long history of manufacturing the highest quality audio processing equipment on the planet. From microphone preamps and compressors, to digitally controlled equalizers with software control, depend on Summit Audio for the highest quality and best sounding audio equipment for your professional recording studio, post production facility, broadcast studio, or performance audio venue. All Summit Audio products are manufactured in the United States at our Northern California based headquarters and undergo strict and vigorous testing. Every piece is individually hand crafted to the highest standards using Audio Precision testing equipment.


Variable input impedance from 10K ohms to 2M ohms XLR mic level output 1/4" TRS line level output Headphone output Up to +24dB output gain Signal ground lift Polarity switch Signal and overload LEDs Internal high voltage power supply One 12AX7A/ECC83 vacuum tube 3 year warranty