In recent weeks, we’ve set out to understand acoustic guitar amplification essentials by creating a high quality amplification system that can be recreated by any guitar player…using commonly available parts. Through this quest, we’ve explored various techniques for acoustic amplifiers, pickup impedance exploration and vocal amplification options as well. Below is the amplified acoustic guitar rig that we created, which produces quite possibly one of the best (live) acoustic guitar tones that we’ve ever heard.
Choice of Acoustic Guitar: Martin D-18VS
As a starting point, we wanted to install a pickup in our Martin D-18VS, which was purchased this year for the Six String Soul studio. This guitar plays like a dream for fingerstyle guitarists, yet is also very playable for bluegrass flatpicking despite being a bit of a challenge due to the wider, 12-fret neck. It’s a bit on the bright side, but the action is perfect and it still plays like butter. The upper bout is sloped like an early-years Martin D-18, and quite reminiscent of the popular Gibson J-35, J-45 and J-50 acoustic guitars. The guitar has a very cool slotted headstock, and overall is quite the classy instrument.
Choice of Acoustic Guitar Pickup: K&K Pure Western Mini
We explored various acoustic guitar pickup options between LR Baggs, K&K and others, and decided to go with the popular K&K Pure Western Mini pickup. This pickup is highly regarded and widely available. The 3-head, bridge plate transducer provides a very natural tone for a passive guitar pickup (no battery to mess with). The total lack of controls also played a role in our decision, as we wanted to completely control the volume, gain and tone with an external preamp.
Choice of Acoustic Guitar Preamp: Headway EDM-1
Made popular by the Punch Brothers and other artists, the Headway preamps really surprised us with the intuitive controls and transparent tone. We compared it against the popular LR Baggs Para Acoustic DI (PADI), amongst other preamps, and found the tonal difference to be night and day. When comparing the Headway EDB-1 and EDM-1 preamps to the PADI, it was like taking a blanket off the tone (more on this below). There was simply more clarity and overtones that shone through with the Headway preamps, yet no brittle high end.
The Headway EDB-1 features two inputs and more controls, but we found the EDM-1 to be perfect for our needs since it features a single channel for the K&K Mini pickup’s single output, a 3-way input impedance selector (one of which was 1 mega ohm, which the K&K Mini prefers), highly effective and simple equalization controls, ground lift, mute switch, volume control and an Anti-Feedback frequency selector. It can be powered by either battery or DC power and even features phantom power (although we didn’t need it for this application).
Choice of Acoustic Guitar Amplifier: Fishman SA220
We want to say this is the most essential piece of our acoustic guitar amplification system, yet it’s hard to discount the tone of the Martin D-18VS and the Headway EDM-1 preamp. The Fishman SA220 acoustic guitar amplification system is simply perfect for acoustic guitar players who want an all-in-one package to amplify both their acoustic guitar and vocals.
The SA220 comes two inputs on the front panel (each has an instrument and mic input), separate input gain controls along with a master gain control, four different built-in reverbs with separate reverb controls for each channel, low/mid/high equalization, phase and anti-feedback controls for each channel. To boot, the back panel features an Auxiliary input (for connecting an iPod, drum machine or other sampled backing tracks), effects send and return for each channel, monitor in and out jacks, a post-mix DI, a tweeter level control, mute and tuner jacks.
But the best part? The vertical array of the six 4-inch high excursion speakers paired with a tweeter in the center offer ultra-wide dispersion never before heard in a dedicated acoustic guitar amplification system. We were floored when we listened to the SA220, and it really pulled the whole rig together. Last but not least, the whole system packs up into an included carrying bag system with rollers. So, you can still load into the gig with one trip.
Lessons Learned from Acoustic Guitar Amplification
We learned a number of lessons about amplifying acoustic guitars along this journey. First off, matching the impedance between the output of your acoustic pickup and a preamp is of the utmost importance. It determine the knee of the low end, which can result in a tone that has too much bass (which you’ll have to compensate for by reducing overall bass frequencies on the preamp, and losing some body in the tone) or too much treble (which you’ll have to compensate for by reducing overall high frequencies on the preamp, and losing some transparent presence).
For the K&K mini, we ideally wanted a preamp that had a 1 mega ohm input impedance, and the Active/Low input setting on the Headway EDM-1 preamp matched perfectly. Perhaps an acoustic pickup that needed a higher input impedance on the preamp input would have sounded just fine with the LR Baggs PADI, but not in our case.
Secondly…ask around. We traveled to many guitar stores and researched our options online for weeks before making final decisions. Every rig is different, and the pickup/preamp combination is one of the most important parts. Get that wrong, and the whole rig doesn’t sound right. Get it right, and you won’t want to put your guitar down.
Last but not least, it’s essential not sacrifice tone by consolidating different elements of the acoustic amplification system into a single package. While those do-it-all amplifiers made by Ultrasound, Fender, Marshall and even Fishman may look simple, appealing and affordable…you’re not going to end up with a tone that inspires you to play day in and day out. By taking a modular approach, you can ensure that each part of the amplification system is tailored to deliver the best possible tone.