What's the advantage of a DUAL MONO preamp?
The Amulet MVT system was created right from the beginning as a Dual Mono System. This means that there are two separate monaural preamps (one for each Acoustic Lens transducer) that are combined into a single output. This allows each Acoustic Lens transducer to see exactly the proper impedance matching to ensure that it delivers all of the tone and dynamic range possible.
Most manufacturers that offer a system with two or more transducers use a single preamp to plug them into. Although this is the cheapest solution, it suffers from a number of problems. Paralleling two or more transducers together into a single preamp compromises their performance by allowing interactions between the transducers, increasing distortion, and reducing dynamic range. You are also dependent on the matching of the transducers themselves to get proper balance and tone between the strings, and there is no way to easily adjust them to produce the ideal balance between low and high strings. Also, if the preamp is external to the instrument, then you run a much greater risk of producing hum and noise, and the endpin, the preamp connections and even the cable connecting them become potential sources of trouble.
The Amulet MVT utilizes Trance's newly-designed ACOUSTIC ENGINETM technology, providing each transducer with its own extremely low noise preamp, and providing the ability to easily balance between the two transducers to get the exact response desired from your instrument. These signals are combined to a monaural signal, and buffered to produce a hum and noise free signal at the endpin jack that's ready to plug into any system. This allows you to get the maximum dynamic range and lowest noise possible from the transducers to produce a clearer more defined sound that more accurately captures the nuances and dynamics of your performance.
EQ
EQ (equalization) can be a very useful tool. When used correctly, it can flesh out the inadequacies in your sound, help make up for deficiencies in an amplifier rig or PA system, even compensate for bad acoustics in your performance space. It can also, when not utilized properly, muddy or distort your sound, add noise, and compromise the dynamic range available to you. It is important to think about how or why you might use it, and just where in your signal chain would be the best place for it to be used.
At its most basic level, EQ is a form of controlled distortion. It enables you to affect a specified range of your signal, letting you boost or cut one realm of frequencies, while having a minimal effect on others. Initially, this seems like a great idea, and here is often where trouble starts. Because of the nature of EQ, its use can cause phase problems, add noise to the signal, and reduce the available dynamic range in some cases. A number of acoustic preamps these days have an EQ section built in, ranging from fairly simple shelving types to more complex parametric or semi-parametric types, allowing the user wider control over the affected frequencies.
The downsides here are that you don't get this power for free. Because of the nature of these units, they generate noise along with the boost or cut to the signal they provide. Since the signal from your guitar at this point is pretty low compared to the finished signal that goes to your system's power amps, the noise that is generated here is amplified as well on its journey, translating to an audible (and annoying) hiss or hum by the time it comes out of the speakers. These units are often battery powered as well, which limits just how much a signal can be amplified before it runs out of clean amplification (headroom). Boosting the EQ can eat up the available headroom and compromise the dynamic range to the point where playing too forcefully can inadvertently clip your system. The amplifying components in these type of systems often are noisier as well, because they are chosen to promote longer battery life instead of lower noise or distortion. The result? You turn up the EQ, and hiss noticeably increases.
So, given these problems, what might help?
A much better solution is the keep the EQ as far down the signal chain as possible. Since the signal here will be much larger having gone through more amplification, any noise produced by the EQ will be much smaller compared to the now-beefy signal, and be much lower and less noticeable. It also helps to use a better class of EQ, especially one that isn't battery powered, as they may tend to be more prone to clipping here.
AC powered units tend to have much better noise and distortion specs, partly due to a larger power supply to allow them more headroom, and usually a better set of components that can take advantage of this increased headroom. Many mixers have an insert point on their input channels, and this can be an ideal point to add your EQ using a send/return cable made for this purpose. Looking deeper here, the best solution is to use as little EQ as possible. Ideally, the EQ should be needed sparingly, sort of as the icing on the cake, not as a much needed tool just to obtain a useable sound. Often in recording studios, engineers will use microphone selection, placement techniques and instrument selection to create the desired sound, using EQ as a last resort if all else fails. The same should be true of a well-designed acoustic guitar system. Using pickup selection, judicious placement, and of course, proper instrument selection will go a very long way towards getting that finished sound that you want to present to your listening audience.
