Adding a pickup to amplify an acoustic guitar is one of the most popular mods carried out in our repair shop, but with so many alternative methods of amplifying your guitar picking the right system can seem like a daunting decision. So, here's a quick overview as to what is out there and what system will work best given the environment that you are playing in.MicrophonesMicrophones offer the best way to capture the sound of an acoustic instrument, but they're fraught with difficulties in a live context. For a solo performer playing in an environment where they are not moving about and not much amplification is needed, a good quality condenser may work well – but if you need more than a slight lift in volume a good sound engineer familiar with your set up is definitely recommended, so it's not the ideal set up for most players. It works best in contexts such as demonstrations of vintage guitars, where attention to detail is paramount – in most contexts it's the player that people turn up to hear, not the instrument, so a degree of compromise in the interests of practicality is generally accepted to be the best way forward. Dynamic mics are less feedback prone but need to be close to the instrument and are unlikely to work as well as a condenser, and an SM58 in front of the soundhole is generally the last resort rather than a popular option!Internal mics are a lot less feedback prone but the sound inside your guitar is actually very different to what you hear from a player's perspective, and the sound from an internal mic is generally rather cluttered without a great deal of clarity.Where internal mics work well is when combined with an undersaddle transducer, where they can warm up the sound and add some character – the Fishman Ellipse Blend is a good example of a system like this, and our favourite pickup, the L. R. Baggs Anthem, is similar.TransducersTransducers fall into three categories and are the most common type of pickup found on an acoustic guitarStick-on transducers are generally seen as the budget option for amplifying on the fly – a simple 'bug' pickup that can be attached to the top of the guitar and works by picking up the vibration of the top and converting it to a signal the amplifier or PA can understand. The bug pickups such as the Shadow 711 and Bizzy Bee transducers are cheap, easy to fit, and easy to transfer from one instrument to another. They can potentially sound remarkably good given their price. The down side is they can often sound rather boomy and indistinct depending on placement, and they're very feedback prone so not well suited to playing with bands or on large stages. They also invariably benefit from an external preamp put between the pickup and PA, which adds to the cost.An alternative to the external bug is a transducer mounted internally, usually onto the bridge plate. These internal versions offer a much more balanced tone than the external versions, and have a very pleasant quality which gives a good impression of the sound of the individual guitar – so they're a little less generic sounding than the alternatives. Feedback is still an issue although less so than with the external type, and some models such as the L. R. Baggs I-Beam have a preamp built in. We recommend this system to anyone playing solo acoustic with good quality amplification or high spec Pas.The most common type of pickup mounted into guitars designed as electro-acoustics is also a type of transducer, but in the form of a ceramic strip that sits underneath the saddle of the guitar. These are the pickups most commonly referred to as piezo pickups. This system works extremely well, being resistant to feedback and relatively easy to achieve high volume levels, so for general gigging purposes and particularly playing in a band they're a good choice. A good quality undersaddle pickup with a fixed EQ preamp is generally a fairly cheap way to get a professional sound from your acoustic, with pickups such as the Steve Head coming in at under the £100 mark. The downside of this style of piezo is that it's a cruder way of capturing the sound of an acoustic with a tendency to sound harsh with a slightly thin papery quality to the bass – but many consider this an acceptable compromise given the practical advantages of the system.Magnetic pickupsThese pickups are similar in design to those found on electric guitars and generally clip across the soundhole of the guitar, although there are some such as the Shadow Nanomag that sit on the end of the fingerboard and are somewhat more discreet. Many of the magnetic pickups can be fitted and removed in a matter of minutes, so like the bug transducers are useful if you might want to use them on more than one guitar. The professional versions such as the L. R. Baggs M-1 or the Fishman Rare Earth can be permanently fitted with a jack socket replacing the end pin, and one version – the Fishman Neo-Buster – even doubles as a handy feedback buster. Although the sound of these pickups can be rather generic without a great deal of the character of your specific guitar, many people prefer the mellower tone and richer bass of a pro level magnetic to that of an undersaddle pickup, and they share the same resistance to feedback as undersaddle pickups.Be aware with soundhole pickups – not all guitars have the same sized soundhole, and particularly if you have a parlour style guitar it's worth checking the diameter before taking the plunge. For reference, a standard modern Martin soundhole diameter is 95mm so if you're in that ballpark you're probably OK. Magnetic pickups also do not work on classical guitars as there's no metal in the strings to interact with the pickup.FittingSome of the pickups mentioned are an easy fit regardless of technical ability – if you can work out how to use bluetack you should be able to fit a bug transducer – but many require professional fitting to avoid damaging the instrument and to get the best out of the pickup. Fitting of an undersaddle pickup involves enlarging the end pin socket to install the jack, drilling a hole to pass the cable for the pickup through into the guitar, refitting the saddle to compensate for the height of the pickup element, and seating the pickup and saddle properly so that the tone is even and balanced. Having an undersaddle transducer fitted in our workshop costs £40, and we can usually turn it around in less than a week.SummarySo, to decide on your pickup, you need to have an idea as to what sort of gigs you're likely to be playing, and what your budget is – with that information it's a fairly easy decision. If you want to hear the different types, L. R. Baggs have kindly provided us with a guitar equiped with their M-1 magnetic, Anthem bridgeplate transducer and Element undersaddle transducer, so you can hear for yourself how they sound. So there you go – no excuses not to get that guitar plugged in and gigged!For first hand advice please feel free to phone us on 0161 834 3281 ext 606 – Glen is our onsite guitar repair technician, and there is James, Mike and Chris on the guitar staff who are all well versed in pickup info.