Rocky Mountain Audio Fest Day 3

It’s over. The three-day, 10th Anniversary edition of the Rocky Mountain Audio Fest is behind us. AIX Records had just about the best location imaginable inside the entrance and across from the registration desk. Traffic to our sales table seemed somewhat lighter than previous years but was good enough to make the weekend worthwhile.

I gave my seminar at 9:30 am on Sunday morning. The subject “High-end Audio from Production to Playback” proved interesting enough to get about 30-40 attendees to the auditorium yesterday morning. I was actually surprised to see so many people in attendance. The RMAF always records the seminars and presentations, so you can see my talk online in a few weeks on the website (the videographer will be quite busy editing and encoding the sessions…so be patient). The feedback that I received was very positive and I enjoyed presenting to an interested crowd.

I laid out the case for using high-resolution PCM for producing new projects and discussed the challenges facing alternative encoding and distribution schemes. The most important point made during the one-hour presentation was that older analog recordings are standard definition because of the technology and methods used to create them. When they are repackaged or transferred to high-resolution digital files they remain standard definition. This is a very hard concept to grasp but it seemed to make an impact with the audience.

One of the most visit rooms at the show had a pair of the new M2 Master Reference Monitor speakers from Harmon. They are unusual in a number of ways. Here’s the blurb from their brochure:

“The M2 Master Reference Monitor design leverages JBL’s new D2 Compression Driver which uses two annular diaphragms and two voice coils to deliver extended high frequency response and very low distortion at very high sound pressure levels. The D2 is mated with JBL’s new 2216ND Differential Drive® 15-inch woofer also with dual voice coils, incorporating a patented wire application that reduces power compression enabling linear output regardless of playback level. With these two extraordinary drivers as the engine, the M2 Master Reference Monitor delivers extended in-room response of 20 Hz to 40 kHz for today’s high-resolution recording formats, and remarkable 123 dB SPL at one meter, providing the necessary dynamic range for demanding music and film production.”

Finally, a cost effective speaker system ($36,000 includes 1000 watts of amplification by Crown and a digital crossover processor) that can deliver “high-resolution” audio in the studio or in your living room. There is a professional version and a high-end consumer version for audiophiles. I listened to the reference system in room 482 and was very impressed with the clarity and high frequency extension to the sound. I asked if I could play one of my recordings from a USB stick but they couldn’t use USB input. The folks at Harmon have designed and built a reference monitor that can deliver the ultrasonic frequencies that are contained in my HD-Audio PCM recordings.

These are the speakers that I want to use to run my research project into the perceptibility of high-resolution audio. To run a rigorous evaluation of ultrasonics we have to make sure that the entire signal chain is producing actual frequencies and dynamic range that extends beyond the specs of a CD, vinyl or tape. And of course, we can’t fall into the trap that the Boston Audio Society did when they evaluated material that claimed to be high-resolution but wasn’t.

Stay tuned…I working on getting this project off the ground.


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 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.

6 thoughts on “Rocky Mountain Audio Fest Day 3

  • October 15, 2013 at 1:23 am

    Hope you get this project off the ground. I believe that not enough research has been done into high rez audio (probably since there isn’t too much financial profit) and I hope that your project will give us a better insight.

  • October 15, 2013 at 11:32 am

    Dr. Aix,
    You state “older analog recordings are standard definition because of the technology and methods used to create them”. Please define “standard definition”. I always considered analog recordings as infinite resolution (how much you could actually capture and reproduce are a totally different matter). I am trying to understand where you are coming from.

    • October 15, 2013 at 11:46 am

      George, the categorization of whether a format is standard definition vs. high definition is based on the performance capabilities of a particular format. Analog is not “infinite resolution” at all. It has bandwidth limitations and dynamic range limitations just as any format does. In the case of analog tape (from which most vinyl is least in the classic music period) is capable of 20 – 25 kHz and a signal to noise ratio of about 72 dB (for a first generation tape…virtually all releases from analog tape much less than the fidelity of the original).

      If you compare the limitations of analog tape to the capability of high-resolution PCM digital technology, there ia dramatic difference. The latest AD/DA converters can encode and decode near 130 dB SNR and record up to 48 kHz and beyond. This is the potential of the format…and is not often achieved. Still the format is capable of much better performance and thus I define it as High Definition or High Resolution.

  • October 18, 2013 at 3:58 pm

    Mark, What can we do to help you with this project? I am willing to donate money to help with this. Will that help? I am surprised that this experiment has not already been conducted, and even if it has it needs to be performed several times by independent experimenters to validate the results. With valid results we will start to see consumers ask for the kinds of products from record companies, recording equipment manufacturers, and playback equipment makers that deliver a meaningful, measurable move forward.

    I’d like to to get on to the end-to-end high resolution band wagon but cannot do so unless every link in the chain supports 96K sampling rate at 24 bits deep. Microphones, electronics, storage media, and speakers or headphones. Pure and free of noise or digital artifacts within the 20 – 48,000 Hz range we want to reproduce.
    leaqse let us know what will help. If half the people who read your post donated $100, that would equal $4,500. Could that help pay for lost studio time, musicians, etc.?

    • October 18, 2013 at 4:11 pm

      Alex, thanks for your post. I’m working very hard on this. As a board member of the CEA, I’m preparing a very detailed proposal with a budget that will do this right. I’ll keep you posted. I think you’ve got it right. We need to have an entire production chain that can utilize the 20-48kHz bandwidth AND the dynamic range of 24-bits. THis standard is glorious and plenty to handle HD-Audio. Stay tuned.


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