Audeze talks with legendary mastering engineer Bob Ludwig

May 17, 2022

Bob Ludwig poses with his Audeze CRBN
"I have done a lot of listening... I haven’t heard a single bar of music, of any genre, that didn’t sound its best on the LTA Z10e electrostatic amp with the CRBN headphones."
- Bob Ludwig

Audeze talks with legendary mastering engineer Bob Ludwig

Bob Ludwig is President of Gateway Mastering in Portland, Maine. To date (Feb 2023), Bob is a 13x GRAMMY and 2x Latin GRAMMY winning mastering engineer with degrees in music education, trumpet, and music literature from the Eastman School of Music. A Fellow and Gold Medal recipient of the Audio Engineering Society, he was the first person to be honored with the Les Paul Award for "consistently outstanding achievements in the professional audio industry." He has won many TEC Awards for Outstanding Creative Achievement. Discogs lists over six thousand credits for Bob, the most for any engineer as far as we know.

Notable works by Bob include

Led Zepplin II album cover
The Band album cover
Bruce Springsteen Nebraska album cover
Daft Punk Random Access Memory album cover
Jimmy Hendrix album cover
Patricia Barber Clique album cover

Can you pick out any favorites from your work that you're particularly proud of?

The original “Led Zeppelin II” LP I mastered early in my career has sold on Discogs for over $1590 so I know a lot of people value that original album cut.

I am a huge fan of The Band. I cut reference disks for their “Music From Big Pink” and I mastered their subsequent albums. I’ve mastered the majority of their releases including their very last album.

I’m proud of the work I’ve done with Bruce Springsteen. I started working with Bruce on the amazing “Nebraska” album and I’ve mastered almost everything since then and I’ve re-mastered all his early albums. The recent versions using the Plangent Process to eliminate the flutter and FM distortion was stunning to me, who knows those albums in my DNA.

Other favorites are from artists like Radiohead, Jimi Hendrix, Paul McCartney, George Strait, Dire Straits, Daft Punk and artists with whom I have mastered or re-mastered much of their catalog. They would include my friend Lou Reed, Wilco, The Rolling Stones, Queen, Roxy Music, Bryan Ferry, Elton John, Nirvana and John Mellencamp. 

How would you define your main role on most of the projects you work on?

Mastering is the final creative step in the record making process. The purpose of mastering is to maximize the inherent musical values of a given recording. This is accomplished by enhancing details, re-balancing levels, adding or taking away dynamics, correcting treble, midrange and bass frequencies and so much more!

I stand in the middle of the Artist and their engineer, their producer, their management, and the A&R person from the label, trying to be sure everyone is on the same page and they are happy with the final result.  

People often use me to see what my “take” is on their music and fortunately they are often surprised how much better their music can sound. Mastering is very specialized; sometimes the mix sent to me sounds so good I have to keep out of the way! Often these days a lot of albums are made with very little budget and they need all the sonic help they can get, the old ‘making a silk purse from a sow’s ear’ applies!  

My goal is to maximize the inherent musical values of a recording. This starts by hearing the raw, un-mastered recording and having the ability to imagine in one’s mind how it could sound then know which knobs to turn to make it sound as you imagine! 

How did you get started in music? What kind of music did you listen to while growing up and how has that progressed?

I seem to have always been interested in a wide range of music. My parents often played Jazz on their record player. They belonged to the Columbia Record Club so I heard a new Billie Holiday, Miles Davis, Dave Brubeck or Louis Armstrong album every month. I lived north of New York City so I listened to the original rock and roll DJ Alan Freed on WINS and then the super-station WABC. I started playing trumpet when I was in 4th grade. We had great music teachers in our public schools (5 music teachers in my high school) and they had our band and orchestra playing works by Holst, Stravinsky, Persichetti, Beethoven, Haydn etc. So I grew up with lots of classical, pop and jazz music. When it was time to go to college I had to choose between an engineering or a music school. One of my music teachers convinced me to try out at the Eastman School of Music and I got in. Some of my classmates were incredibly talented. Steve Gadd played in our orchestra as well as Tony Levin, Lew Soloff (Blood Sweat & Tears) and Dixon Van Winkle (Paul McCartney’s engineer). I learned about North and South Indian music from my best friend. I stayed for my Masters Degree in Music Literature, so I know a lot of music!  

I was also in the Recording Department at Eastman. When I was finishing up my Masters, Phil Ramone came up to teach a recording workshop and at the end of it he asked if I would come work for him in New York City which I did. I played trumpet professionally in the Utica Symphony but as Phil’s assistant I heard the super awe inspiring NY studio musicians. I think I worked at A&R Recording for 6 months before I heard a trumpet player miss a single note he was sight-reading! This was in 4-track then 8-track days before everyone got over-dubbing crazy and everyone really tried to get it right the first time.

Can you name any factors you feel majorly influenced the course of your musical life? Heroes, role models, moments, interactions, etc?

I mentioned my high school teachers, my classes and classmates at Eastman. Phil Ramone at A&R Recording-- I consider Phil my mentor. At A&R I learned the art of disk mastering and I got to have some amazing clients: Nonesuch Records, The Band, Lieber & Stoller, Neil Diamond. I got to spend a day with Jimi Hendrix cutting some references for Electric Ladyland (it seemed genuinely important to him that I liked the music!). A big factor was moving from A&R Recording to become Sterling Sound’s first employee. Then moving to Masterdisk and finally, the biggest factor by far was starting my own business in 1992 with Gateway Mastering Studios here in Portland, Maine.

Can you briefly describe a moment of frustration from your past work, and what you may have done to overcome the obstacles? Would you approach it differently now?

I mastered Led Zeppelin II very early in my career, not long after I joined Sterling Sound. The famous engineer Eddie Kramer mixed the album at A&R Recording at 799 Seventh Avenue where I had worked just a few months previously and Eddie naturally had reference disks cut at A&R by the person I trained to take my job before I left. Dave Crawford’s A&R reference sounded very good and Eddie asked if I could do a hotter version. I did that and I cut master lacquers for Atlantic Records, the client. The test pressings (I still have mine!) were listened to and approved by myself, Eddie, the group and the Atlantic A&R people I’m sure. Reportedly the album had advance orders for 400,000 LPs. The pressings were sent to all the radio stations and the initial run was manufactured and shipped.  

Ahmet Ertegun, President of Atlantic Records, apparently gave his daughter a copy and her turntable could not play it properly and it skipped. Instead of contacting me and asking for a safer less hot cut he had the disk cutters at Atlantic studios cut it at a much lower level. As far as I know no one, not Eddie or the group, got to approve those Atlantic cuts. Looking at today I see some have paid over $1,000 for the “RL” hot cut.  

I’m sure you would be surprised to know I never heard anything about this whole skipping situation for years! When Eddie Kramer came back to me to master “Houses of the Holy” he may have mentioned something. So it was very frustrating and I would have done anything the client wished.  

Is there any gear you find yourself turning to most when working on a project? What are some of your favorite tools/instruments recently?

In general we playback client’s sessions on Pro Tools and record the mastered session on the Swiss Pyramix workstation. We do a fair amount of music in the DSD format. Pro Tools can not do sample rates higher than 192kHz. Also, for me, the ‘source’ to ‘destination’ editing layout of the Pyramix is the ideal platform for mastering. If I am mastering in the analog world I am using my SPL MMC1 8-channel surround console with 124 volt DC rails. It is so clean and quiet. I have 6 channels of Massenburg mastering equalizers, 6 channels of Manley Massive Passive tube equalizers and the Manley MU compressor. In the digital domain we use SPL plug ins, Waves, Massenburg Design Works equalizers as well as Fab Filter plug ins.

Do you have any words of wisdom for people who might aspire toward a similar path for their own careers?

Things are so different now. At Gateway when we were hiring we only wanted to see people with a 4 year degree just to know they are serious about their career. A lot of the job is how concerned you are for your clients, being an open and honest person.  

How long have you been working with headphones, and how do you typically use them in your workflow?

I’ve been listening to headphones since 1970 when Koss introduced the Pro 4A headphones that were so decent Koss still makes them! I used the Sony 999 headphones for a long time, then at Gateway Mastering we used mostly Sennheiser phones. Headphones are crucial in mastering for quality control to be sure everything is OK before sending a mastered file out for distribution. Even in an amazing control room such as I have, headphones can make subtle phase changes much more obvious. They are especially good when de-noising a file to check that the de-noise algorithms are not inducing a phase shift over the interpolation.  

How have your Audeze headphones affected your work?

I have done a lot of listening... I haven’t heard a single bar of music, of any genre, that didn’t sound its best on the LTA Z10e electrostatic amp with the CRBN headphones.

It’s really a new paradigm for me: the cohesiveness of every note of the spectrum aligning just right. Bravo!

The LCD-5s are really spectacular. I mean really great. Due to their impedance, the LCD-5s can be driven by almost any source. For a headphone that is portable and could be hooked up to an Audioquest Dragonfly coming from an iPhone and get 96kHz MQA while listening in a car, I can’t imagine it would have any competition! While they are ultimately portable they are also perfect as the centerpiece of a dedicated tabletop unit at home, using them with the extraordinary LTA Z10e amplifier, a Mytek Brooklyn DAC+, the dCS Bartók etc.

Can you tell us what you've been listening to with them recently?

I've been listening to the new Patricia Barber album I mastered at 352.8kHz/32 bit and it’s really stunning.

I was also listening to music from The Band’s second album which I originally mastered in 1969 and it has remained one of my most favorite albums that I have ever worked on.

I have heard this record often during the 53 years from the original vinyl, several re-masterings from time to time (including the recent anniversary editions). Well, with the CRBN/LTA Z10e combination I am hearing things I have never heard before, and that is amazing!