Sonic Satori - An Interview with Mastering Engineer Bob Ludwig or Eleven Questions with Bob
conducted by Michael Mercer

When you think of legendary mastering engineers, Bob Ludwig is a name that should come to mind. He's worked with some of the most prolific artists and record labels over the years and his Gateway Mastering Studios is a top-notch facility. I had the good fortune of getting to ask Mr. Ludwig some questions about his process and music in general. This was a big honor for me, as he's one of my audio heroes. It's engineers like Mr. Ludwig that provide us with the great sounding recordings we often talk about and lose ourselves to while listening. I hope you enjoy this experience as much as I did... 

1: I've realized recently (and unfortunately) that many young music lovers are not aware of the importance of great mastering in the process of making a record.

Could you please tell me why mastering plays such a key role in the end result ((that is, the album, despite the format, getting play on a users system)?

Bob Ludwig: It isn't just young people who are not aware of the mastering process, I was mastering for many years before my parents "got" what it was I did for a living.

Music mastering is the final creative step in the record making process, it is where everything is polished, edited, and the final sound that you will hear when it comes out is determined. The purpose of mastering is to maximize the musicality inherent in the master tapes we receive from the producers, artists and record companies.

2: I remember many years ago, when TAS was still based in Sea Cliff, Long Island, you wrote a letter to Harry Pearson thanking him for the quality of the magazine (you expressed how important audiophile journals can be—I can't remember your exact words, but it was very flattering). What role do you think audiophile magazines and websites play today, with more and more users downloading their music?

Bob Ludwig: My letter to Harry acknowledged that early on, when I was first mastering records, it was The Absolute Sound that kept the concept of the highest quality sound in the forefront of my thinking. It spurred me on to investigate circuit designs better than the "stock" circuits offered by professional gear manufacturers, high-end cables, power supplies and especially high end speakers and amplifiers. So the influence of The Absolute Sound on me caused me to look for better audiophile solutions to create great sound which in turned produced better sounding music to the millions of people who played the result of my work. Competing against facilities like Doug Sax's The Mastering Lab opened my ears as well as Doug was really the first mastering engineer I know of who really had a handle on high-end sound along with his brother Sherwood.

Audiophile magazines and websites similarly keep the benchmark of great sound in the consciousness of their readers, almost all of whom deal with digital downloads.

3: Compression can be such a nasty word when it comes to music playback, but it is also necessary. A friend (who does a fair amount of recording himself) wanted to ask you about the proper use of compression in mastering. We know too many engineers try to make everything loud and then dynamic contrast seems to suffer a great deal. What advice would you give to a young mastering engineer in terms of applying compression when mastering a record?

Bob Ludwig: (I'm speaking about artistic compression that effects dynamics and headroom, not data compression used in lossy codec downloads.)

First I suggest everyone look at Matt Mayfield's brilliant 2 minute video for a clear explanation of the "loudness wars" and the over-use of compressors that is a blight on our sonic landscape.

http://www.youtube.com/watch?v=3Gmex_4hreQ

Many genres of music, but especially rock/pop music demands compression of some sort in the recording and often the mastering stage as it is an intrinsic part of the "sound" of the music. No live rock/pop music is ever professionally performed without the use of compressors. Rock is big and huge, and the illusion of that sound on a recording can only be artistically created by compressing elements of the recording, mix and usually mastering.

Jazz, world music etc. many or may not need compression. Compression on the bass instrument to even out the playing and make it fit in the mix more clearly, sure, compress a Bill Evans solo piano recording, no!

Classical music rarely needs to have any compression and seldom does.

My advice is to only use compression that makes the music sound better and is not done for loudness sake. Good compression brings many things to the table:

1. Better consistency from song to song

2. The recording can sound better on a greater number of playback sources (it can sound good in a car as well as earphones and speakers).

3. It can add incredible punch to a lack-luster recording.

4. It can bring out low-level details that add artistically to the enjoyment of the song.

5. It can make the recording sound "competitive" in that one can listen to a variety of recordings and one may not have to turn the volume control up or down.

If you mix and master records with these guidelines you will always have a result you can be proud of. If, as is so often the case these days, a client feels the level of the final result is too low in level, one can always further compress until the client approves it. If you over-compress it to begin with, there is no going back except to re-do it.

4: Speaking of compression, many people believe you cannot get a download to sound good no matter what you do. I disagree, not that I feel the overall dynamics of a download can equal that of an LP (or can they)—but I play a great deal of downloaded music at home through a decent DAC and system, and I'm surprised at how good it can sound. Do you master things differently for iTunes for example?

Bob Ludwig: Apple has begun a new initiative called "Mastered for iTunes" which greatly improves the sound of iTunes AAC encodes without changing a single piece of hardware on the 250,000,000 players in the field. It can be so dramatic you can easily hear the difference between the new and old technology on your little laptop speakers.

Instead of ingesting the music from a CD rip or 16-bit file, the new system uses 24-bit master files for the encode. The AAC encoder can make use of bits 17-24. An important addition is the realization that the act of AAC encoding can cause clipping where there was none on the original PCM .wav or .aiff file. In classical music this encoder induced clipping can occur at the occasional climaxes or in a typical over-compressed pop/rock recording, many times a second. Apple has created tools to log the number, severity and time of each clip so the mastering engineer can lower the level of the 24-bit master by fractions of a dB and the clips and resulting distortion from them is eliminated.

It is a complicated answer, but a 24-bit AAC encoded file can thus sound better and measure better in certain cases than a normal 16-bit Compact Disc, which unfortunately has been regarded as the gold standard for sound in these comparisons.

5: I have always admired your choices in gear for your studio. Your facility is top-notch. Are there any pieces of hardware that hold a special place in your heart, that is: Are there any pieces of equipment in particular that you feel are necessary during your mastering process?

Bob Ludwig: There are several pieces of gear I feel are necessary for doing the best mastering and foremost is my monitoring system with the bridged Cello Performance Mark II amplifiers feeding my custom 790 lb. Eggleston Works Ivy speakers, serials #1 and #2 which have 23 drivers in each cabinet. They both sit on concrete pedestals that are isolated from the studio's floating floor. They are driven through Transparent Audio's best Opus MM2 speaker cable.

You might find the next piece of gear odd, but it really makes a difference. It is our 2 refrigerator-size batteries that power the studios. We create our own 60Hz. The power is super clean. The bridged Cello amps can put out 4000 Watt peaks, but you can put your ear right up to the Eggleston Works' Esotar tweeter and it is really silent, no noise. Next would be my Pyramix digital workstation. It sounds transparent, it can do both PCM 382kHz/32-bit as well as DSD and it's ability to have Source-Destination editing makes editing very quick and efficient. It is a joy to work on this system.

Then my Sound Performance Laboratory (SPL) 8-channel surround analog mastering desk is essential. It is ultra-state-of-the-art with 124 volt DC rails amplifiers. It's amazing.

Some other gear that gets used a lot would include my Manley tube Massive Passive equalizer which helps get rid of "digititis" on some digital sources.

6: We know the music industry has experienced sweeping changes in the past few years thanks to digital/internet distribution. Have you seen any negative effects flowing into the music you are working on? I mean, I get into arguments all the time about the fact that there is still fantastic music being made today (in all genres, from dubstep to acoustic folk music)—do you see a downward turn in what you believe to be quality music being released today (knowing that all art is in the eye of the beholder)?

Bob Ludwig: There definitely is still great music being made, check out the new Wilco album, and of course new classical masterpieces seem to be created all the time. On a personal level, I can't tolerate the sound of audible vocal-tuning, so naturally it became a fad to incorporate it into all the big pop hits! There is great stuff out there, the internet makes it more difficult to filter the good stuff than it used to be. So many thousand of songs are put into the market place every week, it is a challenge to discover some wonderful sounds.

7: The advent of home recording had a big impact on recording studios, especially when some of the bigger artists began to make their albums at home or on their own terms. However, most of these artists are not engineers, and so they still need a technical hand to sculpt the music into a mix that's coherent. Did you also see a decrease in demand for mastering services? Are the bulk of your clients still major labels, or is it split between labels and indie artists?

Bob Ludwig: With so many recordings being done in basements and garages, the need for good mastering is greater than ever, although due to lack of budgets many people who desperately need mastering can't afford it. Our clients used to be largely record companies, but today they are joined by management companies and individual artists/producers.

7: Having your operation in Maine seems to give you an edge, as it allows you to work in an environment that is free of countless distractions (though I'm sure you get slammed). What brought you to Maine, is that where you are from?

Bob Ludwig: After finishing up my degrees at Eastman in Rochester, NY I spent the years I worked at A&R Recording, Sterling Sound and Masterdisk in the New York City area. My parent had lived in Maine for many years and I fell in love with it and when I decided to start my own business, Gateway Mastering Studios, I decided that Maine was the place I wanted to be and I've never regretted it one bit. Portland is a very special city, it is usually high on the "best cities to live in" lists and it is a very cultural city, some amazing musicians up here!

8: If you weren't located in Maine, what would be another dream location for you to work out of?

Bob Ludwig: I'm so comfortable here, any other place ultimately sounds like a nightmare to me!

9: I like to write about music in the early morning hours, when the noise floor surrounding our home is at it's lowest. I know your room has exceptional isolation (both physically and electrically—I remember reading about it), but is there a certain time of day that you prefer when working on projects?

Bob Ludwig: I usually spend a long day 9am-7pm mastering every day, so I can't even think of having the luxury to only work during a specific part of the day! Being human, when I'm near the end of a long day, I try not to start anything new for the last few minutes of the day. I listen at 85dB so it is loud enough to hear critically but never enough of a dose to do any damage to the hearing. My ears never ring from loud monitoring at the end of the day!

10: I've always considered you an engineer who appreciates both the recording process and the importance of proper playback. Many engineers slam audiophiles. I was surprised to experience this divide when I went to work for Arif Mardin while I was at Atlantic Records. Why do you think these engineers are so skeptical of audiophiles and audiophile reviewers?

Bob Ludwig: I think that many professional engineers and producers look down on audiophiles because audiophiles don't know what it is like to make one's living and career as a professional engineer. It is often based on compromise.

When making a record, the artist's performance is everything, it is what makes the record worth buying. A good producer will keep a great performance even if there is something technically wrong with it. Often an artist will want to intentionally distort something, or make something with limited dynamic range and this can frustrate audiophiles who think that the cleanest recordings are the best ones to demonstrate their equipment. Recently an audiophile magazine reviewer said how much he liked the sound of a new Puscifer album I did and, while it is intentionally distorted in may places, it is an amazing sounding album, so there is hope!

11: I know that you work on all types of music, so I would never ask you to single out any artists in particular that you like—but is there a certain type of music that moves you the most?

Bob Ludwig: I love music that is inventive and well done, be it Wilco, Coldplay, My Morning Jacket, Bruce Springsteen or the Kronos String Quartet. Naturally, coming from a Symphonic background, I am deeply moved, sometimes to tears, by the world's greatest classical artists. I just heard a concert by the great French countertenor Phillipe Jaroussky in Boston. He scored a 10 out of 10 in my book, a perfect concert. They say he has "the tone of an angel and the virtuosity of the devil." There aren't many people on the planet that could sing even one phrase of his repertoire. The mind-blowing melismas and 16^th note runs he does clearly and perfectly in tune, as well as being a consummate interpretive musician, made the concert a tribute to the rare ability to achieve perfection that only a few humans can hope to do.