Guitar Compression By Brian Tarquin

Compression can be a very subtle effect, especially on electric guitar or it can be used in extreme fashions. There are many things to consider when using a compressor on a guitar. For instance, when miking a tube amp that is overdriven, the tubes are actually compressing the signal, so there is really no need to compress when recording. But on the other hand, when recording an acoustic guitar live with a mic there are many sound transients that affect the dynamics of the guitar strings. Hence compressing the track helps to control the musical integrity of the performance to your recording source. I sat down with 3 distinctly different gunslingers to discuss their take on compressing guitar.

Robin Trower
“Seven Moons was recorded in London at Intimate Studios. I recommended it to Jack Bruce because I like the acoustics in the room – wooden floor – not too dead – very good for guitar and drums. I used 2 Cornell Plexi” 18/20 amps – these are the 20 watt 1×12 combos. I would split them from my pedals – running one clean and one more overdriven. We used a Shure 57 a few inches from each combo thru a Summit DCL 200 (stereo valve comp) & Urie 1176. My pedals were a Fulldrive II and a Clyde wah – both by Fulltone as is the Deja-vibe. The guitar was my signature model Stratocaster from the Fender custom shop built by Todd Krause. The neck pick-up is a fifties re-issue. The middle is a sixties re-issue and the bridge pick-up a modern winding for more oomph.”

Tommy Emmanuel
“We mixed at Wistaria Studio in Virginia. Kim Person engineered the album. She is a real great engineer and specializes in acoustic guitar. She can get such a great natural sound from the guitar. Kim used Pendulum preamps & compressors, which were made for her studio. I used a Neumann KM184, pointing down the neck of the guitar, towards the sound hole. Right in front of me, I used a hand made mic that a friend of Kim’s had designed, similar to an old Telefunken 251 centered to the sound hole about 8” in front of me. I also took a direct out from my guitar pickup into my AER acoustic amp that was in a separate room and miced it. When we did the mix, we left all two acoustic guitar mics dry and put just a little reverb on the amp mic that created that beautiful big depth. That real crystal clear sound, like you’re right in front of my guitar. ”

Steve Vai
“Most of the stuff is close mic’d, but the change in pitch of the microphone gives the distinction. Also, EQ plays a vital role. I always keep a pair of C14s and a pair of 414s (Mics) spread apart in the corners of the room. This is mixed into the sound at various levels depending on the desired effect. It’s important to me to try and create a space for each guitar; the song should tell you what to do. I usually use Wave and Renaissance plug-ins for EQ, then compress analog before it hits the drive. I’m not a fan of digital compressors or reverbs. However during mixdown, I usually use an L1 limiter plug-in.”

It is interesting to see how differently each one of these guitar heroes approach compression. Trower creates his classic tone by using the Urei 1176, while Tommy takes the audio file route by using the pristine clarity of the boutique Pendulum Audio compressor. As for the shred master, Mr. Vai takes the dual approach of using both analog & digital compression; using the Waves L1 for its renowned transparency and punch. All great choices, but you may want to still consider trying other fantastic compressors, both vintage and new when recording/mixing guitar tracks.

Urei LA-4

One of my all time favorites is the optical Limiter Urei LA-4, probably one of the best compressors for a guitar. It is extremely transparent, very easy to use and is very flexible. The difference between the LA-4 and its predecessor the LA-3A is the added RATIO control, without the added confusion of Attack and Release controls introduced on newer optical limiters. Any tech will tell you that the whole beauty of Opto’s in general is their simplicity. In fact, it shines on just about any stringed instrument, whether bass, acoustic guitar, electric guitars, Rhodes and even the organ. The best trait of this limiter is that it is actually difficult to make if sound bad. I have a pair that I had recapped and the quality of sound that it produces on a lead guitar and solo is mind blowing. It handles the guitar signal flawlessly, without loosing the tone or dynamics. This is something of utmost importance, YOU DON’T WANT TO DISTURB THE TONE YOU WORKED SO HARD TO GET RECORDED! I generally use it on various guitars during a mix to control everything at the final stage.

Purple Audio MC-77

Do you like the classic FET sound of the Urei 1176? Well think of the MC-77 as an 1176 on steroids. This bad purple monster kicks some serious booty! It has the identical controls of the 1176, but has a fatter squash. Just like the 1176 the front panel has two large knobs, two small knobs, a meter and two columns of buttons. The large knobs adjust input and output level; the small knobs adjust attack and release times. And yes, it has the all buttons capability to really get that crush for drums. In fact, when I record drums I put a mono room mic through it and push all the buttons in to get a pseudo Bonham sound. But I love using it on guitar, especially crunchy rhythm guitar to give it some girth. It also shines on bass to give it some presence in a mix, without the muddy effect. I usually track using the MC-77 on rhythm acoustic guitar to control the transients, while bringing out the attack of the pick on the strings. Now this is a bit more colored sounding than the LA-4, but used in the right way, it has wonderful results in a mix.

Anthony DeMaria 1500

The brilliance of Mr. DeMaria comes all out in this fantastic sounding limiter. Similar to the LA-4, the 1500 utilize Opto attenuators to create “invisible” compression. It’s a 2-channel; all tube design, with phenomenal dynamic range. It boasts eight vacuum tubes giving it unmistakable richness and depth. This unit has an incredible cross platform use from being a beefy buss compressor to limiting individual instruments. I love using this on guitars; the tubes add fullness without coloring the signal. On acoustic guitars- forgetaboutit! It makes them stand out with a creaminess of tube circuitry. I usually route 2 rhythm guitar tracks through them in stereo to achieve a warm presence in the mix. The only thing you have to be mindful of is your headroom; you can’t push them like the 1176 without getting undesirable distortion. So for those of you who record directly in a DAW with amp modeling plug-ins, this would be the ideal compressor for you to have at mix down, to warm up that cold digital signal.

Anthony DeMaria 670

This is the Rolls Royce of limiters; some may call it the “Holy Grail” of compression. It is a reproduction of the classic Fairchild 670. It is truly a sonic beast, but sounds unbelievable. On guitars it adds such an incredible punch and clarity delivered from the 18 tubes and 14 transformers, really putting the F in Fat! It’s hand made like a tank with “military strength”; every detail has been scrutinized to perfection to recreate the original. Surprisingly, very easy to use having 4 control knobs, input gain, ratio, DC threshold, and a fine-tune threshold. These last 2 controls are interactive with each other and is a fantastic idea. You can set your threshold point and then use the fine tune knob to dial in a compression point you are seeking. The saying “a little goes a long way” is very true when using the ADL 670 on guitars. You don’t need to see the VU meters moving about to get the compression effect. On rhythm guitar there is punch the limiter gives, especially if you a have real crunch tone. But the great thing about this limiter is that it delivers a velvety, smooth sound overall that creates fullness in the track for guitar.

Overall, I believe the trick to understanding compression and how it works is experimenting with different compressors on guitar and seeing how it interacts with the track. Some compressors just don’t do it for a guitar track; no matter how hard you try. Keep in mind that compressors are designed to keep the dynamics under control in a track, so be very careful not to over use on guitar, or you’ll hear the pumping or what is known as “breathing” of the guitar, which means back off the compressor. The most important factor for me when choosing a compressor for guitar is how it will enhance the guitar without coloration to the tone. There are some guitar tracks you may never need to compress like a hi-gain lead tone. The tubes of the amp have already done the compression and the higher the gain, the less dynamics, because the pre-amp gain stage in the amp is doing just that, compressing the guitar tone with the gain sound. Be careful to always monitor the VU meter during gain reduction as well, because it is very easy to over do it. Generally -3db is a safe place to be, use your ears & you will be fine.

About the author
Brian Tarquin is a Multi Emmy Award winning composer/guitarist and owner of Jungle Room Studios. Some of his accomplishments include, writing the theme music for MTV’s Road Rules, as well as producing music for many other TV shows such as CSI, ABC’s Making The Band, Extra, Alias and the Keanu Reeves film, The Watcher. In 2006, Tarquin opened his own boutique record label called BHP MUSIC, specializing in instrumental guitar music. Brian is also a featured music writer and has been published in magazines such as EQ, Guitar Player, Premier Guitar & Recording.