About Tak

Guitarist. Teacher. Audio Engineer. Based in Toronto. I love talking about music, performing, and any topic it might intersect with.

Acoustic Guitar Mic Placement

Amplifying an acoustic guitar with a microphone can be tricky. The instrument is often susceptible to feedback and sound engineers frequently ask you to use a pickup to compensate. If your pickup system is a soundboard transducer (like piezo elements under the bridge saddles) then the result is a highly unnatural sound that only partially translates the beautiful acoustic sound. However, knowing a few things about microphone placement can help tremendously in taming feedback while still getting a natural sound that only microphones can capture.

Proximity Effect

In the microphone world, there is something called the proximity effect. The proximity effect describes the tendency for a microphone to pickup more bass frequencies, the closer it’s placed to the sound source. This concept is important in taming low frequency feedback and getting a balanced sound. A common mistake is that guitarists will tend to position themselves so that the microphone is as close to the soundhole of the guitar as possible. The area directly in front of the soundhole is where much of the low frequencies of the instrument are picked up; combined with the proximity effect it creates the perfect situation for feedback to occur. To solve this, try to stay about a foot away from the microphone when possible, and angle it away from the sound hole. The 12th fret is a common target to point a microphone towards. If you’re using a clip-on mic, try and follow these guidelines with the limited mobility of the microphone.

If you’re still getting feedback after placing the mic in the optimal position, try using (if available) a phase switch to reverse the polarity of your signal or use an equalizer to dial out the problem frequencies. Just remember these options are best used AFTER you’ve gotten a balanced sound through microphone placement. I hope this helps in getting a better live sound for you!

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Understanding Effects: Compression

Compression, short for dynamic compression, is a topic that confuses pros and amateurs alike. In fact, it can take some people years to thoroughly understand how it is affecting our audio signal and to fully utilize the many applications of dynamic compression. I believe the confusing aspect of this effect is that the difference in sound can be quite subtle, making it difficult to associate the turning of dials with the change in sound.

Here’s a step by step of what happens to a signal going through a compressor. First, a volume threshold is set. The audio signal needs to go past this threshold in order to activate the compressor. You also need to understand that a compressor will only affect the part of the audio that crosses this threshold. You can also control how fast the compressor reacts to the signal going above and below this threshold by controlling the “attack” and “release” setting. These controls are important in targeting the portion of the signal you want affected/unaffected. Once the compressor is triggered, the signal is reduced by a set ratio (oftentimes 2:1, 4:1, 8:1). Say for example, a signal that is 6dB over the threshold will now only be 3dB loud with a ratio of 2:1.

Threshold

The threshold is the minimum amount of volume needed to engage the compressor effect. Therefore, if the signal you are dealing with is too quiet and below the set threshold, the compressor will never engage. The compressor releases after the signal falls below threshold. On many stompbox compressors, the input gain is adjusted relative to a fixed threshold. In other words, you control how much signal goes past the threshold by adjust the volume of the signal, instead of adjusting the threshold itself.

Ratio

As explained earlier, this is the ratio at which the original signal is compressed. The greater the ratio, the more dynamic range (difference between loud and soft parts) is lost. For guitar pedals, this ratio tends to be fixed but generally set around 4:1 or 8:1. When the ratio is 20:1 or greater, it is considered to be functioning as a limiter and has other uses associated with it. Lower ratios will have a much more transparent effect on the sound.

Attack/Release

The attack and release parameters may also be fixed on certain guitar pedal compressors. These controls adjust the speed at which the compressor engages and releases when crossing the threshold, and is typically measured in milliseconds. It’s important to adjust attack so that it is affecting the part of the sound you want to, namely the transient or the tail. The transient is the “attack” of the guitar string when being picked. If you were to look at a visual representation of a guitar note in a DAW, you will see the attack as the loudest portion of the sound and the tail of the note as a steadily decaying waveform. Generally speaking, you want to set the attack at a speed which avoids compressing the transient, and engages on the tail. The release setting will be more dependant on the style of guitar you are playing. A funk rhythm guitar will likely have a quick release so that it doesn’t affect the next strum, where as sustained lead notes will have a slow release to keep notes from dying out too soon. Some digital compressors will have an automatic release control that responds intelligently to your playing.

Make-up Gain

A compressor, by definition, will reduce the overall volume of a sound. The make-up gain is there to “make-up” for any lost volume by adding some gain after the effect has taken place. It is meant as a corrective tool, so all you need to do with it is to set it so that the processed sound is at the same volume as the original signal.

If your guitar tends to have loud/soft spots, or you’re still having problems controlling the volume of your picking or strumming, there is a lot to be gained by using a compressor. What you may lose in dynamic range, you will gain in dynamic consistency which is an important part of genres such as funk. Furthermore, it can also be a way of protecting your precious equipment by reducing sudden spikes in volume that can harm speakers and overload power amps. Tonally speaking, it’s a great way to add punch and warmth to your guitar sound in a subtle way and might just be the thing you need to take your sound to a “professional” level. Have fun!

The Signal Chain

I’ve referenced the idea of the “signal chain” in some past posts, and how it helps to conceptualize how your sound is developed through the various equipment that your guitar passes through. It’s a concept that will help you achieve the tone you want, consistently.

There are a couple of adages in the audio engineering world (and many other professions) that goes: “crap goes in, crap comes out”, or sometimes “you can’t polish a turd.” They both mean essentially the same thing: get it right as early as possible or you will pay for it later with less than desirable results (and time wasted). There is no “fix it in the mix” and there is no “my garage sale guitar can sound like Eric Johnson if I get the right amp.”

How should guitar players aim to get it right at the top of the signal chain? The first step is your technique. Have you ever noticed how an artist sounds like themselves no matter what gear they play through? This is because their technique and stylistic approach to music has been developed for years to create their sonic signature. Having well developed technique will also enable you to adjust your playing to any guitar so that you may get the best possible sound out of it. Always be looking to improve your technique and you will never lose your sound on any piece of gear.

The next step in the chain is the guitar. If you’re playing a solid body electric guitar, the strings and pickups are going to create the biggest difference in sound. If you’re playing an acoustic guitar, the wood of the soundboard will be the biggest contributor to tone. When it comes to strings, the materials matter but the biggest factor may be string tension. String tension is affected by factors like string gauge and action. It will affect the amount of sustain you can get from your guitar and will also change the amount of attack relative to the sustain. Pickups are a matter of personal taste but the most important factor is whether they are single coil or humbuckers. Choose from the many hundreds of after market replacements, what will complement your style the best.

Before we get further down the chain, I just want to mention one thing about connectors (IE patch cords, cables, etc.) Your monster cable, gold plated connectors, oxidation-free vacuum-sealed whatevers are pointless. Don’t invest your hard earned dollars into them because they won’t make a difference. I recall an experiment done by audiophiles where people couldn’t tell the difference between Monster Cables and a coat hanger. The two most important attributes for cables are that they’re insulated well and are durable.

From the guitar, the signal travels to the amp. A lot of people say that amps are probably the most important factor in getting a great electric guitar sound, but see how far down the signal chain it actually is? If we had gotten all of the previous components wrong, then no amp is going to remedy your sound. However, if you had everything right to this point, your guitar stands a chance of sounding good and even amazing on many amps. The (combo) amplifier can be further divided into its components: the preamp, poweramp, and speaker. You can take what you get with the combo amp or delve into the world of customizing your amplifier setup as well. That’s a massive topic that’s beyond the scope of this blog entry.

The environment/room is the final stop in a signal chain before the sound reaches your ears. In most scenarios you won’t have the option of customizing the environment, but it’s important to learn to compensate for it. Some rooms have hard surfaces like concrete walls that will create a cacophony by reflecting the sound everywhere. Avoid using reverb in these situations as they’ll just muddy up the mix. Other rooms may create resonances as certain frequencies that will need to be compensated by using an equalizer. Even the amount of people in a room will affect your sound, as human bodies can dampen sound reflections.

I hope I gave you some ideas on how to think about building your sound in a logical way. Enjoy!

Guitarist vs. Musician

What is the difference between a guitarist and a musician? For that matter, between any instrumentalist and a musician? Is a guitarist a musician by default? What is meant when someone says that so-and-so is a “musician’s musician”?

I like to think there is a difference between a guitar player and a musician. The guitar player’s focus is the instrument. They may be highly accomplished on their instrument, knowing every obscure technique or being able to shred it like there’s no tomorrow. When you listen to their music, though, you might feel that something is missing. Have you ever felt that way? I certainly have. If you take this approach to the extreme, you may even have a guitarist who is quite accomplished but unable to play with other musicians. Even if they are able to play music with other musicians, they may not be able to complement a solid groove laid by the drummer and bassist. They may ruin moments of inspiration with self-indulgence.

A musician, however, is someone who might be equally skilled but is tuned in with the music as a whole. A musician’s mentality is to serve the music, not the instrument. The instrument is only a means of expression. Technique is a means to an end, and not the goal itself. These artists focus on their own music, but also know how to compliment and add to what other musicians are doing, and in a variety of settings. They are highly adaptable. They are satisfied with playing a single note at times, because that is what best served the music in the moment. They don’t care if they couldn’t throw in that flashy lick over that fancy chord.

I believe that when these two attitudes merge, you get what people call a “musicians’ musician”: Someone who is highly accomplished on their respective instrument and is able to play in a way that compliments their band-mates and elevate a performance to something that is greater than the sum of its parts.

So, ask yourself: “Am I a guitarist or a musician?” more importantly, “which do I want to be?” I hope you opt for the latter, because it will open so many doors for you!

Gig Preparation Checklist

If you’re inexperienced with playing live shows, it can be an overwhelming experience to get everything in order to make sure the show runs smoothly. Preparation is the name of the game, so here’s a handy checklist to help you avoid common mistakes people make:

  • pack a spare of everything
  • scope out the venue beforehand
  • talk nice to the sound guy, he knows what he’s doing (most of the time)
  • learn how to communicate your needs to the sound guy
  • make sure you can all hear each other and yourselves (don’t be too loud)
  • know what gear is available at the venue for you to use
  • arrive early to soundcheck, and do your best to minimize this time by being prepared
  • make sure you have access to power if you’re using amplification
  • don’t forget sheet music and music stands if you use them
  • if you read music off a tablet, don’t forget that and have a stand for it too
  • make sure your gear is in working order
  • bring extra patch cords and connectors as they tend to be the first thing to fail
  • prepare a setlist
  • don’t get drunk before playing
  • be well rehearsed
  • keep the stage clear of clutter, it looks unprofessional and you have less mobility on stage
  • have a stage plot to make sure you have a line of sight with your band mates
  • know when set times and breaks are and follow them
  • be prepared to deal with hecklers

I’m sure I’ve missed some points, as you can never be too prepared in show-biz. In my experience, anything can go wrong! This list should serve as a pretty good guideline to cover most bases, though. Good luck with your next gig!

The Volume Knob

Here’s a little fact that you may not have known about the volume knob on your typical electric guitar: it actually changes the timbre of your guitar as you move it.

Without getting into the technical aspects, as a volume knob is turned down it will typically remove high frequencies along with lowering the overall volume. Don’t believe it? Try playing through a guitar amp with the volume knob at full blast, then turn the volume knob down and turn the amp volume up to compensate so it stays at the same volume. Notice the difference in tone? It can be subtle, but it’s there.

For the most part, this won’t cause any major problems. You just need to realize that if you’re going to adjust your instrument volume through the volume knob on the guitar, the tone can vary drastically depending on where it’s set and you must compensate for it.

There’s a psycho-acoustic phenomenon where sounds with a lot of higher frequencies are actually perceived as being “closer” to you. By reducing volume AND higher frequencies, you are actually pushing the guitar further back in the mix than if you were to only reduce volume. Try and use this to your advantage, by allowing some room for other high frequency instruments in your mix to come forward (especially vocals!) Another way to approach this concept is to start with the volume slightly lower and boost for solos. If your sound includes distortion, it will also affect the quality of distortion.

I mentioned earlier that there are some guitars that compensate for this effect that is a natural part of the volume knob: some volume knobs do the opposite and actually reduce lower frequencies as the volume is turned down. Personally, I prefer this sound much more since the guitar isn’t really a low frequency instrument, and the effect is far more subtle.

One other fact you may not have known about volume controls are that they can be either linear or logarithmic in the way they attenuate volume. Linear volume controls are more common but logarithmic volume controls perceptually increase/decrease volume in a smoother way to the human ear. Linear controls will have spots on the control where the amount of  volume (perceptually) changes suddenly.

The volume knob is one of the immediate controls at your disposal in a live setting, so understanding its full potential can unlock a lot doors for you. No need to reach over to that amp as much. Have fun!

Understanding Effects: Delay

Delay is an effect that is generally used to create a sense of “space” for a guitar sound by imitating a sound reflecting off of a wall. This is not to be confused with its more complex cousin, reverb. It’s a pretty straightforward effect: have the original signal duplicated but delayed by a defined interval of time, usually measured in milliseconds. It’s a fairly easy effect to use so I’d like to focus a little more on the parameters and the different categories of delays that can be used.

Delay Time

The most important adjustable parameter is the delay time. The delay time is often sorted into four categories: doubling, slapback, echo, and loop. Doubling is the shortest amount of time, between 30-50ms. When delay times are this short, the delay signal is actually perceived as a single sound but with a sense of stereo separation (if it’s panned left and right); similar to a unison performance.  Slapback is a a very short delay between 75-250ms, and creates a sound that’s reminiscent of a tiled room. This is a defining feature of Nashville recordings from a certain era, where vocals were often thickened with this type of delay. The echo effect, where it begins to sound like you’re playing into a mountain valley or cavern, is around 250ms-800ms. It creates a large and almost surreal sense of space, finding frequent uses in psychedelic styled music. Some artists set the echo time to a rhythmic unit of a song (the Edge from U2 likes to use a dotted eighth note value) to achieve an effect reminiscent of an arpeggiator. Once we get into delay times in the range of seconds, we enter the realm of looping. Looping is used to repeat and layer musical ideas to create a one-man orchestra performance. Outside of these typical uses, guitarists like Tom Morello (Rage Against the Machine) have made novel sounds by changing the delay time as he is playing.

Feedback

The feedback control adjusts the amount of a delay signal that gets fed back into the delay signal path. The result is that you are able to control how many “echoes” you can hear against the original sound. It’s a good idea to keep the feedback amount very low, and even more so when there are longer delay times. This is because if many echoes are lasting a long time, they will begin to layer on top of each other, eventually obscuring the music. To simplify, you can think of feedback and delay time having an inverse relationship. That being said, there are creative ways of using infinite echoes, as this is not something that happens in nature and can create a psychedelic touch to your music.

Levels

The next important parameter is the level, or mix parameter. The delay signal is usually set at a lower level than the original signal, to imitate the energy loss of sound reflecting off of a wall. You can also create greater separation between the two sounds by applying a bass cut or treble cut on the delay signals. This is a useful trick if you’re having trouble achieving clarity of sound when using heavy amounts of delay.

Once you get a handle on the more common uses of this effect, you can experiment with some tricks. One well known trick is to set a delay pedal to the value of a dotted eighth note in whatever piece of music you’re playing, but play a constant eighth note line. This is a trick that is used by The Edge from U2.

Analog vs. Digital

Digital delays are characterized by a clean and pristine delay of the original audio. Analog delays have more “character” to them, because analog equipment naturally introduces noise to the audio signal. What is interesting is when the delay feedback increases and the signal is fed repeatedly through an analog delay, the quality of each delay degrades progressively. This is a characteristic sound of the “dub” style of music that is popular in Jamaica.

I hope you got some useful ideas from this! Until next time.