Fig. 1
Our columnist breaks down the science behind the dB unit specific to digital systems, and divulges a perennial question about comparative amp loudness.
Hello, and welcome to another Dojo. Last month, I focused on the history and development of the VU meter, and then defined some of the more confusing terms regarding decibels (dB, dBu, dBA, and dBSPL), as well as various ways to measure loudness and amplitude. I also asked: “Is a 100-watt amp twice as loud as a 50-watt amp?”—the answer shall be revealed presently. But first, I’m going to focus on a relative newcomer to the scene: dBFS. Tighten up your belts, the Dojo is now open.
More dB Terms?
What is dBFS? It is relegated to the digital realm, and whenever you hear this term, I want you to remember the following joke: “What sounds better than digital distortion? Everything!”
You see, dBFS (decibels full scale), is the unit of measurement for amplitude within a digital system (such as your DAW), and all digital systems have a maximum peak level before clipping (overload) occurs. A reading of 0 dBFS is the highest signal level achievable for a digital audio. Unlike the analog world, where brief moments of being “in the red” of the VU meter won’t adversely affect the audio, dBFS digital “overs” are squared off (or, mercilessly guillotined), and clipping occurs. It sucks, and is to be avoided at all times. The audio irony is that, when or if you see those two teeny-tiny rectangles above your master fader turn red (Fig.1), you’ve got big problems, and need to turn everything down in order to avoid clipping when you bounce/render your mix.
Is a 100-watt amp twice as loud as a 50-watt amp?
I’m going to answer this by helping you learn some more about how we perceive loudness, and I’ll be using dBA as our mode of measurement. Because, as you’ll recall from last month, using dBFS treats all frequencies equally, and that’s not how the human ear works. In other words, our sensitivity to frequency, sound level, and duration vary across our general range of hearing (20 Hz to 20 kHz). Specifically, our hearing has evolved to be most sensitive between the approximate ranges of 2 kHz and 5 kHz.
Using this range as a yardstick, audiologists agree that 3 dB (up or down) is the minimal detectable change the average person can hear. In my experience, in a critical listening environment, I—and anyone else in the studio—can easily hear 1 dB changes—this especially happens when mixing and mastering.
“The audio irony is that, when or if you see those two teeny-tiny rectangles above your master fader turn red, you’ve got big problems.”
However, to increase the sound, 3 dB requires twice the power (intensity). An increase of 6 dB requires twice the amplitude (voltage), and an increase of 10 dB sounds to the human ear twice as loud. Stated another way: +3 dB is 2x the acoustic power, +6 dB is 4x the acoustic power, and +10 dB is 10x the acoustic power. For those who are mathematically inclined (I am not), here is the decibel formula: dB = 10log10 (S1/S2), where S1 and S2 are the intensity of the two sounds.
Remember when I said last month that decibels are based on a ratio, and they are logarithmic? Now we want to look at the relationship of decibels and power. What is the international unit of measurement for power? It’s the watt (W), named after Scottish inventor James Watt (1736–1819). Check out these relationships:
Number of Decibels | Relative Increase of Power |
0 dB | 1x |
3 dB | 2x |
10 dB | 10x |
20 dB | 100x |
30 dB | 1,000x |
50 dB | 100,000x |
100 dB | 10,000,000,000x |
So, let’s say we have a lovely vintage 4x12 cabinet, and we have two amps that we are going to run through it—a 50-watt head and a 100-watt head (both with matching impedance). Using this relationship, we can answer our previous question! Our 50-watt head is the starting point and baseline for measurement.
Let’s say that, as we play our latest epic jam through our dimed 50-watt head, our drummer comes over and says, “It’s not loud enough! They can’t hear it in the parking lot of the Waffle House across from the stadium!” So, we switch to the 100-watt head thinking it will be twice as loud. Wrong! Go back and look at the chart above. We’ve doubled the power (2x) and that only gained us a paltry increase of 3 dB! That’s right, a 100-watt amp is only 3 dB louder than a 50-watt amp. So, what would be twice as loud? Do the math—we’d need a 10x increase in watts (50 W × 10), so a 500-watt amplifier (or 10 dimed 50-watt amps, simultaneously) would be needed! (Yes, but do they go to 11?)
Until next time, namaste.
TL;DR: You’ve gotta believe in yourself to make things happen.
Bohlinger asks: Is life a cosmic vending machine, or can we manifest our musical goals?
The law of attraction, or manifesting, has been in vogue for a while. I first heard about this semi-spiritual belief that you will attract into your life whatever you focus on back in 2006 with The Secret, Rhonda Byrne’s popular self-help book (and film) that’s sold over 35 million copies worldwide and been translated into 50 languages.
Essentially, positive thoughts and actions reap positive rewards, negative thoughts and actions reap negative outcomes—your thoughts determine your reality. To get there, follow these basic rules:
Focus on what you want, not on what you don’t want.
Don’t get attached to the end result.
Stop complaining.
Find ways to elevate your mood daily.
We live in the age of string theory, where spirituality and science meet, so anything is possible. But even if you take out the science and spirituality, I know there is something to this hippie mumbo jumbo. Here’s how it works on a practical level for musicians:
You’re performing a song that has a difficult bridge. You know that the bridge is coming up, and the voice in your head says, “You’re going to mess this up, and you will feel deep, painful shame.” Sure enough, a few bars later, you mess up the bridge.
Here’s how it goes the other way: You have a gig coming up where you are playing that song with the bridge that you always boff, but this time you say to yourself, “Damnit, I am going to finally take the time to learn that stupid bridge and get it right.” So, you spend 10 minutes or 10 hours playing it until you have it right. You play it so many times that when you go to bed that night, the bridge is playing in your head on a constant loop. When you close your eyes, you can visualize your fingers working out the notes. You picture yourself playing it slowly, quickly, with a swing, really straight, then drift off to sleep with the song still looping under your dreams. At the gig, when that bridge comes up, you feel a bit of anxiety creeping in and say, “I got this.” And you are right. That’s the power of manifesting.
“Once a person makes a decision to walk away from the card table, they are not going to win the big pot.”
You can also experience this socially. If you stay positive, look for the good in people and situations, the people around you will tend to move in that direction as well. As an added benefit, staying positive tends to repel chronically bummed-out pessimists, who do not want to hang with people on the up. Misery loves miserable company, not optimistic company. All those Wednesday Addams-types tend to avoid what they consider naive, stupid happy people.
Same goes with a career in music. Interstates 440 and 65 are like conveyor belts, delivering an endless supply of young and old aspiring artists to Nashville to make their mark. In my 30-plus years working here, I’ve seen the wildly talented and the not-so-talented succeed and fail. The only thing the successes have in common is that they do not quit. That does not mean that the never-quitters are going to succeed. But once a person makes a decision to walk away from the card table, they are not going to win the big pot.
Here’s an example: Joe Bonamassa just released a 20th anniversary version of his game-changer album, Blues Deluxe. Bonamassa said, “If you had told me 20 years ago my career would last long enough to see the 20th anniversary of this little record called Blues Deluxe, I’m sure I would have laughed…. Blues Deluxe was my last shot after being dropped by two major record labels and my booking agent.” I have no idea if they had a law-of-attraction mindset, but Bonamassa and his manager, Roy Weisman, went all-in on their own project and turned their ideas into a host of Billboard-charting albums, never-ending tours of sold-out shows, the philanthropic Keeping the Blues Alive foundation, and an incredible collection of guitars and amps.
Maybe it’s manifesting, or maybe it’s just that if you believe in yourself and keep working, you will improve and find opportunities. The harder you work, the luckier you get.
As a kid, I read Dostoevsky’s Notes from Underground and it changed my life. The bitter protagonist wastes his life living underground, feeding his anger and self-loathing with constant complaints. This is highly paraphrased, but he said something like:
“Only fools succeed, because an intelligent person knows that intelligence and hard work doesn’t matter, you will fail. So only fools succeed because they are too stupid to know they will fail.”
I signed up for this fool’s errand and never regretted it.
Supported by Keeley, Scan the code or visit robertkeeley.com/lastcall for a special offer!
When it comes to power supplies, don’t underestimate their importance—an unreliable, low-quality one can lead to serious pedal malfunctions.
Let’s begin this article with my personal experience as a pedal builder and a novice musician. One day, a customer messaged me, sounding a bit frustrated. “I received the pedal, but it won’t light up. Did it get damaged during shipping?” they said. I promptly began troubleshooting.
I started with clarifying the signal source, checking if the installation of the input and output jacks was correct, and, finally, inquiring about the power supply being used. To my surprise, he replied, “I’m using a laptop power adapter. Shouldn’t that work just fine? My laptop is in good shape with it. Have I made a mistake? By the way, this is my first pedal ever.”
For a moment, I couldn’t help but wonder how incidents like this were still occurring. It reminded me of a time 20 years ago when I struggled to power my pedal with a phone charger, and it happened to be at my first gig! Do you think this is a funny story? Definitely not! I’m sure most of us have been there at some point. Beginners in any field share two common traits: lack of knowledge and lack of experience. However, we’re currently in an era where a wealth of information is readily available at our fingertips, including this article, which I hope will serve as an informative artifact that is accessible to everyone.
“For a moment, I couldn’t help but wonder how incidents like this were still occurring.”
As pedal builders, we pay particular attention to power supplies, especially during the testing and quality-control processes. In fact, we’ve conducted experiments with various power supplies, ranging from the cheapest ones available on the market to ones made by well-known brands with a strong reputation.
During our experiments, we plugged all these power supplies into a variety of pedals and let them run continuously for a week. The results were astonishing: Two power supplies burned out, and one of them was from a renowned brand in the power supply universe.
We conducted these experiments not out of sheer curiosity. The electrical grid in our country, Indonesia, is notorious for its poor quality. Voltage fluctuations are common, and event organizers will sometimes haphazardly use power generators, lacking proper planning. That’s why we felt the need to experiment with power supplies and their impact on pedals. Moreover, I am fairly confident that most of us choose to buy a power supply as infrequently as possible, so we can spend our money on buying more and more pedals, adding some boutique overdrives, or expanding our collection with the latest and greatest delay units under the guise of “upgrading.”
Well, in the end, the choice between buying the fanciest delay unit and upgrading to a proper power supply is a matter of personal preference. If you can afford both at the same time, it’s undoubtedly a smart and ideal choice. However, are we always in an ideal situation? Most likely not. That’s why I’m using this platform to convey a message to all of you: A proper power supply, especially an isolated type, is the most valuable and crucial investment in a pedalboard! (Isolated power supplies offer one-to-one connections with the pedals on your ’board, so if one channel of the supply goes down, other pedals will remain powered.)
This becomes even more critical if you’re a touring musician with a highly complex pedalboard setup. In such cases, an isolated power supply is an absolute necessity. The stages you’ll visit can be unpredictable and even chaotic! No matter how advanced and costly your pedal collection is, if you’re using a low-quality power supply, all those sophisticated and expensive pedals are at risk of becoming useless or, worse, suffering fatal damage. This can occur due to voltage drops, which can lead to malfunctions or excessive, disruptive noise, rendering your entire setup completely useless.