Music Video: Slayer's 'Repentless'
Issue: September 1, 2015

Music Video: Slayer's 'Repentless'

BURBANK, CA — When editor Ed Marx got the call from director BJ McDonnell, asking if he’d cut Slayer’s new music video, he couldn’t say “yes” fast enough! Marx, who has a body of work that spans the horror genre, including film, television and shorts, blocked out a week to cut Repentless, the debut video from the band’s 11th studio album of the same name, released on September 11th.

To describe the music video as a full-scale prison riot would be an understatement, as a jail’s entire prison population escapes from their cells, overtakes the security staff, and exacts revenge on guards and other inmates. Beatings, stabbings, lots of blood and even a decapitation make their way into the piece, which runs approximately 4:30 and features 230-plus edits.

The project was shot at the Sybil Brand Institute, a correctional facility for women east of downtown Los Angeles that closed in the late 90s. It begins and ends with short narrative segments — the front end with the prisoners breaking free, and the closing segments with one prisoner, covered in blood, voluntarily returning to his cell. In between, Slayer unleashes their one-of-a-kind thrash metal style, with singer/bassist Tom Araya screaming above heavy guitar tracks by icon Kerry King and Gary Holt. Drummer Paul Bostaph’s speed and quick hits set the break-neck pace.

“As somebody who works in horror, there is a parallel between the rabid fan base of metal and horror,” notes Marx, who cut the video on his Mac-based Avid Media Composer. The video had approximately 1.5 million views in less than a week, a sign of the band’s dedicated fan base.

The project was shot in 5K using a single Red camera. A crane was used to capture swooping shots of the band, performing in the prison’s yard, while the chaos ensues and riot police, armed with clubs, shields and helmets, try to contain it.


“BJ and I talked,” says Marx of the edit. “I asked him, ‘How aggressive I should be?’ He said, ‘Dude, go for it!’”

There are numerous, short sequences of the different prisoners that needed to be featured — attacking each other, and the guards —  including one played by the very recognizable Danny Trejo.

“The thing that decides whether it’s going to be ‘cutty’ is the material,” says Marx. “The material tells you how it’s going to be edited.”

Marx worked with a LUT provided by DP Eric Leach, and transcoded the footage to 4K resolution for the ultimate delivery, but performed the edit at ¼ resolution. 

“The first thing I do is make sure the song I get is a frame-for-frame synch up of playback,” he explains. “The performances are all synced to the song, which makes the edit process go a lot faster. Kerry, Tom…were all group clipped. Wide shots were grouped, so finding shots within the song was simple.”

Marx attended the band’s shoot at the prison and recalls how hot it was that day. “It was killer. The group did 19 takes, and it was a brutally-hot day, but Take #19 was no less energetic.” He was impressed with how tight they were able to play in sync with the playback sound. “Kerry is a mad man — he never missed. Paul never missed!”

The edit came together pretty quickly, he recalls. “We hit it pretty fast early on. There were six or so revisions, [but] we agreed on the overall structure.”

Company 3 in Santa Monica handled color correction for the video (Before and After shown), with Bryan Smaller adjusting the blues in the interior prison scenes and highlighting the dry outdoor setting of the prison yard, as well as the prisoners’ bright orange jumpsuits.

Music videos are notorious for being budget strapped, and while Marx had a number of other projects in the works, he felt this project was just one he couldn’t pass up.

“It’s Slayer!!” 


Michael Kammes (, who had worked with Marx on several projects prior to Repentless, handled the music video’s sound design.

“Ed reached out to me a week before the video was due to be released,” Kammes recalls. “While the performance and edit turned out very well, the story surrounding it was a bit sparse in terms of sound design. I kicked around some conceptual ideas following Ed’s mix, and after a phone call with the director, BJ McDonnell, I felt we were in a good place and in sync on tone and feeling.”

The bookend narrative segments for Repentless were MOS, so all of the sound had to be created from scratch.

“The slowed motion in the scenes really allowed me to experiment with the reality of the sounds — emphasizing some effects over others, and also manipulate various types of reverb to really shape the space,” Kammes adds. “I’m a big fan of dynamics, or more specifically, the perception of dynamics, in a mix. You can’t have sweet without sour, and you can’t have loud without soft.  I wanted the bookends to contrast starkly against the song.  

“The cut Repentless is an all out auditory assault, and having something a bit less intense on either end would be able to accentuate that assault. I did focus on some common sonic themes to make sure the viewer was locked into the vibe of the piece: the jail cell door, eerie wind, etc. — common sound effects, but ones that really had to sell the grittiness of the video. In the end, many new sounds were created downwind of the library choices to fit the piece.”

To balance the dynamics, Kammes says he spent a significant amount of time tweaking the soundtrack to keep the volume high at the front and tail parts of the video – but not so quiet as to have folks twisting their volume knobs up and down. 

“During these parts, I used a slight bit of maximizing,” he explains. “I also added a tiny bit of emphasis at 100Hz and 10kHz to combat the frequencies that routinely get rolled off during compression of video for Web. It’s all about finding a happy medium for volume and pleasing the vast majority of the viewers on the most amount of mediums.”

Kammes performed audio post at his home studio, which is centered around a 2014 MacBook Pro, running Pro Tools|HD 11.  

“I’ve moved to iZotope for most of my plug-in needs, and Soundminer is an excellent tool for finding, auditioning, and spotting the sound effects that were needed. I run this off of a 20TB home NAS, which makes accessing all the sound libraries that much easier.  This was a stereo mix that I monitored on my Event 20/20 speakers.  They’re older, but I rarely get ear fatigue and they’ve always translated well.”