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Why use a Tube Mic Preamp?
Think of what a guitar sound would be like if the preamp in the guitar amp was
inferior. You’d have a colorless, lifeless guitar tone. This is the same principle with
recording preamps. Of course, there are preamplifiers in mixing boards.
However...
Mixer manufacturers often need to make trade-offs to keep prices down while keeping performance up. Imagine the price of your mixer if each channels’ preamp cost over $200 (and we’re not talking about those of you who have one of those $250,000+ consoles!)
This isn’t a new concept, but it has become more relevant with the availability of affordable mixing consoles. As their name implies, most affordable mixers excel in signal routing and mixing capabilities. They are not necessarily your best option for the actual recording of tracks. While their onboard circuitry is nearly always clean and quiet, the simple truth is that good microphone preamps have a more flexible collection of (and better sounding) circuits.
In recording, the shortest signal path is the best way to get a signal to tape. In most cases, the shortest path is: mic to preamp to compressor to EQ to tape deck. The signal doesn’t even go through the mixer!
The use of external preamps has sonic and practical benefits when you consider that most recording is done one or two channels at a time. For those of us on a budget, it just doesn’t make sense to spend a ton of money on a "Cadillac" console when a budget mixer and a few pieces of external gear is more cost effective. Even those engineers who regularly work on "big" consoles use external preamps!
The goal of any recording is to get the sounds right before you commit them to tape. ART Mic Preamps exist to help you get it right when you record. It’s the affordable and sonically preferable way to record.
Tube Preamplifier Applications: The main application of a microphone preamplifier is as a processing channel for a microphone, instrument or line level source. In most cases, outboard mic preamps offer superior performance to the on-board preamp on your mixing console.
So how do you use an external mic preamp? It’s easy. To use a mic preamp instead of your on-board preamp, simply connect the output of the outboard mic preamp to the line input of your mixer’s input channel. Plug directly into the outboard preamp’s input and set the input and output controls to provide an appropriate level into the next stage of your system. You can connect the XLR output jack of the outboard preamp to the XLR input of your mixer, however most affordable mixers do not allow you to bypass their internal preamp when using the XLR jack. You will cause no harm to either unit when doing this but you will probably experience slightly higher noise. This is due to the fact that you are now preamplifing your mixer’s preamp. (Important - Be certain that you do not connect the outboard preamp’s XLR Output to a mixer input that has Phantom Power applied.)
To use a mic preamp as an instrument preamp, simply plug the instrument into the Input jack and connect the Output jack to the input of a power amplifier. ART Mic Preamps have enough gain to be used in front of a power amplifier.
ART Mic preamps are ideal for use as a DI box. Plug the instrument into either input and use the XLR, 1/4, or both outputs to connect to your recorder, board, or PA system. Experiment with different input level settings for different textures.
So you want special effects? For industrial, metal, or just "flavor" textures, experiment! Overdriving the preamp circuitry can add interesting textures when blended with vocals and other instruments. Placing signals purposely out of phase can also yield interesting results. No harm will come to the mic preamp with this type of experimentation. However, be sure to have output and monitoring levels turned down before "testing" the sound. Remember - you have a great amount of gain available with ART preamps!
Additional Design Notes: ART Tube Preamps and their award-winning designs will allow you to obtain professional recording studio results at a fraction of the cost of comparable equipment. The designs of the ART mic preamps allow you to add warmth and fatness to a signal while maintaining an exceptionally low- noise and high quality signal.
Used as a direct recording channel, a mic/line preamp, or a DI (direct) box, they are designed to work seamlessly with any recording, sound-reinforcement, or electronic instrument setup.
A R T’s Tube circuitry is a hybrid design utilizing the latest, most advanced, solid- state and tube technology. With a transformerless design, they maintain exceptional signal integrity and extremely low noise. The preamplifier’s active balanced solid-state input provides extremely low noise and excellent CMRR. The 1/4" input has a high impedance, which prevents the loading of any device connected to it and makes them perfect for DI or line level applications. The preamplifier’s second stage 12AX7a tube runs on a regulated DC voltage providing an additional 40dB of gain. Our design enables the tube to overload before the input or output stage. This allows you to manipulate the tube gain to meet different sonic requirements.
