Dr. AIX's POSTSTECH TALK

Getting Great Sound: Part I

Setting up a great sounding music playback system is more than just having the right source components, cabling, amplifiers and speakers. Your listening room plays a critical role in getting right sound, too. It is, after all, an acoustic chamber that has the ability to modify the sound that emanates from your speakers before it gets to your ears. Your room has the potential to become a large Helmholtz resonator.

Most of us don’t have the luxury of building a custom listening room or home theater from the ground up. We take over the family room, den or the basement and do our best to tame the irregularities that affect the balances between a “flat” response and one the hypes the low or high end.

At the university audio studio, I played some of my tracks during a class for a group of students. The tonal characteristics that came from the small powered studio monitors were not good. The sound was harsh, the mid range was missing and lower octaves were anemic compared to my own very well balanced studio.

What does it mean to have a “flat” response? Why is it important? How does one get a room to deliver a “flat” response? These are some of the questions that need to have answered if you’re going to get your entire music playback system to its ultimate potential.

A flat response happens when the entire range of frequencies are balanced from the lowest to the highest frequencies. Take a look at the graph in Figure 1. The red line shows the amplitude of the music across the audible frequency band. It is desirable to have the energy distributed equally and avoid bumps or troughs that would change the correct “color” of the sound.

frequency_repsonse_graph

Figure 1 – A “flat”speaker response in a listening room.

You want to hear the tonal distribution of the music you enjoy listening to exactly the same way that the mastering engineer heard it in their calibrated studio monitors. Mastering rooms are some of the most expensive studios in the entire production chain in terms of the monitors and the highly refined acoustics that must be maintained. If it leaves the mastering room with something amiss, the experience you have in your space will suffer.

So what is the ideal combination of equipment, expertise and architectural alterations that will deliver a great sound room? Obviously, you’re going to have to get a set of speakers that can deliver an even blend of sound across the entire frequency range. You’re also going to want to consult a professional when it comes time to “tune” your room to the ideal “flat” response…really this is not something you can accomplish yourself. And finally you’re going to have to do some room treatment to minimize the negative impact of your space’s parallel walls, multiple hard surfaces and regular dimensions.

Once we get done with a few posts about getting the best out of your system, you might start thinking about a really great set of headphones.

Dr. AIX

Mark Waldrep, aka Dr. AIX, has been producing and engineering music for over 40 years. He learned electronics as a teenager from his HAM radio father while learning to play the guitar. Mark received the first doctorate in music composition from UCLA in 1986 for a "binaural" electronic music composition. Other advanced degrees include an MS in computer science, an MFA/MA in music, BM in music and a BA in art. As an engineer and producer, Mark has worked on projects for the Rolling Stones, 311, Tool, KISS, Blink 182, Blues Traveler, Britney Spears, the San Francisco Symphony, The Dover Quartet, Willie Nelson, Paul Williams, The Allman Brothers, Bad Company and many more. Dr. Waldrep has been an innovator when it comes to multimedia and music. He created the first enhanced CDs in the 90s, the first DVD-Videos released in the U.S., the first web-connected DVD, the first DVD-Audio title, the first music Blu-ray disc and the first 3D Music Album. Additionally, he launched the first High Definition Music Download site in 2007 called iTrax.com. A frequency speaker at audio events, author of numerous articles, Dr. Waldrep is currently writing a book on the production and reproduction of high-end music called, "High-End Audio: A Practical Guide to Production and Playback". The book should be completed in the fall of 2013.

Leave a Reply

Your email address will not be published. Required fields are marked *