Jeroen Paul Thesseling: The 7-String Fretless Master Returns

With Obscura’s new release the Dutch bass virtuoso takes his unique style to new depths sonically and compositionally

Jeroen Paul Thesseling: The 7-String Fretless Master Returns

With Obscura’s new release the Dutch bass virtuoso takes his unique style to new depths sonically and compositionally

Jeroen Paul Thesseling is an anomaly among bass players. While he has become a trailblazer in technical, progressive, and death metal, his roots and inspiration come from jazz fusion and baroque composers. He brings all of the shredding low end that is required in those genres but focuses on melodic counterpoint phrasings that take the spotlight as much as the lead guitars, which usually fuel that music. And instead of relying on drop D tunings or B strings like his contemporaries, Thesseling takes it even lower into subsonic territory with his 7-string basses that boast a low F# string. On top of all of that, he plays only fretless basses, which is rare for any genre of metal.

Having the opportunity to see Thesseling’s colossal 7-string fretless Warwick Thumb basses and hold them in-person is a humbling experience in itself. Their sheer mass and giant fingerboards, which seem endless in every direction, make even the most expert player feel novice in attempting to play it. Requiring great strength to support it, remarkable intonation to convey the notes, and extreme finger dexterity to traverse the width of the neck, it’s hard to imagine how something so improbably strenuous could be used as a tool for musical creation. But the real lesson in humility comes in watching Thesseling shred on it so effortlessly.

His latest release with his German technical death metal outfit Obscura, A Valediction, demonstrates every bit of his mastery. It also celebrates his return to their lineup after a 9-year hiatus to focus on the band Pestilence and various other projects. Jeroen’s presence is impactful throughout the course of the 11 songs. Between locking in with lightning-fast double kick drum patterns and doubling blazing guitar lines, his bass provides the backbone for the highly praised released. From his low F# string to his high C, he covers every bit of his fingerboard with wildly orchestrated parts while proving once again that he has a playing style all his own.

Congrats on the release of Obscura’s A Valediction. What was the writing process like for this album?

It was a very positive experience sharing ideas with each other after taking a break for nine years. When the new lineup was completed, we started to discuss our musical direction, focused on some material that was already written, and started sharing arrangements and melodies. Obscura’s main composers are Steffen Kummerer and Christian Muenzner. Despite the new material that was built with the recognizable elements Obscura used earlier in their previous productions, this sixth studio album turned out accessible and at the same time still progressive. Compositions still contain many technical elements to them, but with this production it feels like we approached a more grown-up sound.

Was creating this album difficult because of the pandemic?

Besides a few writing sessions that both guitarists had together we recorded everything remotely in our own studios. The pandemic started to rage during spring 2020 and it made us decide to postpone the release date for six months. That gave us more time for the writing process, and we were even able to work out the full album as a pre-production. This was a great advantage for us being able to figure out how things were going to sound and which arrangements or parts needed some changes before starting to work on the final tracks. When you’re on the same page it makes the musical collaboration so much easier.

Your playing on this record is super technical. What was your approach to writing your bass parts?

It was a long process going through all the pieces and working out several options for bass. Since I didn’t work with an engineer on my side there was plenty of time to reconsider and re-record ideas that were recorded as first drafts. Of course, a bass line should be functional in the first place, but often I try to challenge myself by adding something different to drum patterns or guitar tracks to create more diversity. During my youth I used to play violin, which is an important factor of adding melody-oriented bass lines in most of Obscura’s productions. The material for A Valediction also offered a lot of opportunities for counterpoint arrangements. I’ve never added so many counterpoint-oriented lines on an album like this one.

How did you capture your tone for this album?

With Obscura I always use three DI channels. One dry channel is used for sub-low to low-mid frequencies. The other two channels (in stereo) are used for the low-mid up to high frequencies. With this method you create a solid low sound and combine it with the stereo signal, which makes fretless bass sound wider in the mix. Before sending the three bass tracks to our producer in Sweden, the left and right channels were routed separately with different settings through one of my favorite units: the Kush Audio Electra electrified transient equalizer. This piece of gear adds a great punch by tweaking certain midrange frequencies and it accentuates the stereo image of my bass sound.

Does playing a 7-string bass make it more difficult to get a balanced mix of all your frequencies?

The dynamics of a 7-string bass with a low-F# tuning make it sometimes a little more difficult compared to a regular 6-string bass tuning. During the production process we used a multiband compressor which pushes the tonal spectrum more in balance. My signal chain runs just through a pair of Warwick PR40 bass preamps [designed by Jonas Hellborg]. It’s short and sounds solid while also very clean. It worked well to add the sub-contra register in several album productions.

This type of music is typically very guitar driven, but your bass stands out at all times. How would you describe the role of the bass in Obscura?

Since Obscura’s second full-length album, Cosmogenesis, fretless bass has had quite a prominent role in most of the songs. Sound-wise it became sort of a trademark. I still remember the first three tracks we recorded as pre-production in late 2008, where we simply needed time to figure out a right balance in the compositions between guitars and bass. In many Obscura compositions my bass arrangements exist out of counterpoint-built patterns, jazz-fusion elements, or melody-oriented fragments. The combination of these styles formed a certain signature playing on fretless bass. The combination of different genres like baroque music and jazz-fusion enables me to add more diverse bass arrangements.

Which are your favorite songs to play from the album and why?

“Solaris,” “The Neuromancer,” and “The Beyond” are my favorites right now. Quite demanding songs to play but they bring a nice diversity. We’re used to working with certain structured patterns. These “baroque”-influenced parts work very well and are most often present in material written by Christian Muenzner. We’ve recorded three Obscura albums together and musically Christian and I are totally on the same page. Most of his compositions form an ideal basis to add my bass arrangements. Another example of this is the earlier recorded song, “Universe Momentum” from the Cosmogenesis album.

What is it like playing in a rhythm section with David Diepold?

It was a great pleasure to track bass together with David’s final drum recordings. His playing turned out extremely smooth and he added a very natural flow to the songs. Quite often you hear the typical blastbeat drummers playing with a somewhat “squared” character in technical [death] metal productions. Of course, this is also a matter of taste, but I definitely prefer an organic sounding drumming style, which suits better with my playing. So yeah, it was an amazing experience to record with David. He’s a huge talent and one of the most promising drummers in the technical/progressive metal scene.

What is an Obscura show like from your perspective?

Obscura shows require focus, but at the same time in most cases I enjoy the moment of the concert. In this technical genre, muscle memory is something you develop quickly. But you want to make sure everything is sounding tight, with the right intonation and dynamics. And quality monitoring is everything, as you can easily get lost. How can you perform with good intonation without hearing the guitars? In that sense I’m pretty old school and still prefer bass cabinets behind me and powerful wedge monitors in front of me to have rest of the instruments clearly audible.

Tell us a little about your playing technique.

I’ve never focused much on playing technique, but over the years it developed slowly into a more classical playing style for my left hand, which was already used to the fingerboard of a violin. And since playing flamenco style, my right-hand got more dynamic. When it comes to expression sound-wise, it’s often the sound character of the wood that you need to work for. At the same time, I try to avoid being bound to extreme EQ settings. Playing chords on fretless requires very precise finger positioning on these fingerboards, so you want to be in control of that.

What led you to playing a 7-string bass?

During the recordings of Pestilence’s Doctrine album both guitarists used 8-string guitars. We tried several options to record with my fretless six-string but adding a sub-low F# string sounded so much better in the production. Immediately after we finished the album recordings, I contacted Warwick and asked if they perhaps could build a fretless Thumb NT7. They needed to redesign the body, neck, and headstock since it was their first seven-string version of the Thumb NT. After a few months Warwick sent me the new NT7 design in 3D format. Not much later the prototype Thumb NT7 fretless was delivered at my home in Amsterdam. It quickly became my main instrument and I’ve been playing it exclusively. The 7-strings enable me to play with the sub-contra register to push massive and solid-sounding accents in my playing. It worked very well recording the A Valediction album, despite the fact that my bass isn’t as present in the mix as it was on Obscura’s previous productions, Cosmogenesis (2009) and Omnivium (2011).

What are the more difficult elements of playing a 7-string bass?

It’s not that much more difficult than playing a 6-string fretless bass. It’s most important to master the intonation on a broad fingerboard. The B-through-­G strings of a 6-string are still the most important for me. The extra challenge is to control the sub-contra F# string with the right expression. Sub-low bass strings produce a lower volume and therefore require more attack than the rest of the tuning. This is something you get used to and learn to balance with the rest of the strings.

Tell us about your custom Warwick basses.

The Warwick Thumb bass is famous for its mid-frequency-oriented character, which suits the technical/progressive death metal style very well. It has to do with the very clear articulation the instrument provides. The bubinga body, the striped wenge-bubinga neck and the fingerboard options are all woods with a very high density. The three fretless Thumb NT7 custom shop basses Warwick “masterbuilt” for me are all based on the classic Thumb NT series. Nevertheless each instrument has a different type of fingerboard wood. First we used ebony in 2011, then the ultra-dense snakewood in 2013 and ended up with tiger stripe ebony again in 2017. My experience with ebony fingerboards is that they are easier for traveling since snakewood is extremely sensitive to temperature and humidity. For album recordings I choose which bass sounds best to the music style. All Obscura productions were recorded with an ebony fingerboard.

How have you developed and matured as a bassist to this point of your career?

There were several stages in my career where I focused on specific musical challenges. Combining different styles of music has always created this drive and being progressive minded. For several years I experimented with microtonality, which got me into world music. Back in 2006 it was a flamenco project I joined that made me decide to play exclusively fretless. Since then, development of intonation is always a priority for me, and the classical background has always been an important element for my bass playing. I’ve never really felt attracted to the idea to master other modern playing techniques. It was the musical approach, wanting a specific role for bass guitar in a certain group or project that mainly fascinated me. It turned out quite successful with Pestilence’s fourth studio album Spheres (1993), and later on with my recording project Ensemble Salazhar. From 2008, it was Obscura who gave me the opportunity to add my own musical stamp and signature playing to their compositions.

Which bass players have inspired you the most?

Carles Benavent has been the most important influence as far as sound on fretless bass. His signature fretless playing is incredible. We both have in common that we play melody-oriented lines. Also, Eberhard Weber is a very important influence. Furthermore, I have to mention Steve Bailey, master virtuoso fretless player who adds his very own colors and plays with amazing dynamics. Contemporary classical string quartets have been an important influence in creating new ideas, and listening to those works made me curious to look for a different approach on fretless. The three Obscura albums I recorded offered enough opportunities for such influences and bass arrangements.

How and when did you first start playing bass?

I started playing electric bass while attending a local music school, in 1985. It was the same school where I previously took violin lessons for eight years. During my high school studies, the greatest challenge was staying away from school and playing bass guitar at home. After about a year they kicked me out of school, which enabled me to focus fully on the instrument. Not much later, I continued to study bass, mainly jazz-oriented, at the conservatory ArtEZ School of Music in Enschede, the Netherlands. Back then it wasn’t always easy to catch up with lessons by my teacher, Ruud Ouwehand, but now I’m so grateful for what he taught me. He lent me his bass just to get an idea about what playing the fretless was like.

Why bass? What attracts you to the instrument?

During my violin studies in my early teenage years I didn’t feel comfortable with the frequency range and sound character of the instrument. Even playing in a big orchestra didn’t truly satisfy me. There was just something missing and often I wished to play a more powerful or maybe more deep and solid-sounding instrument, like the cello. But while attending high school the motivation to continue with classical music dropped and it made me switch radically to bass guitar. I immediately fell in love with the tonal range and the character of the instrument. In fact, it was a great opportunity for me to work out everything I learned in classical music on a modern instrument, and it may have been my classical background which initially pushed me to play fretless bass exclusively. –BM

Hear Him On: Obscura, A Valediction [Nuclear Blast, 2021]


Bass Warwick Thumb NT7 Fretless with Ebony Fingerboard (Custom Shop, Masterbuilt 2011), Warwick Thumb NT7 Fretless with Snakewood Fingerboard (Custom Shop, Masterbuilt 2013), Warwick Thumb NT7 Fretless with Ebony Fingerboard (Custom Shop, Masterbuilt 2017)

Rig Warwick Hellborg PR40 Preamps (stereo pair), Kush Audio Electra Electrified Transient Equalizer

Strings Warwick Black Label, stainless steel (.175-.135-.105-.085-.065-.045-.025)

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Jon D'Auria   By: Jon D'Auria

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