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Frans Van Ryhovelaan
9000, Gent


A great mastering engineer needs a great set of ears, and a great set of gear.
This is some of the equipment in Jerboa’s Mastering Studio.


  • GRACE / MERGING Premium PCM-DSD converters
  • GRIMM TPR cable
  • KII Three
  • KOLD. IT
  • Merging Pyramix DAW



    • ARREL AUDIO ML-116
      Monster Line Mastering EQ
    • ARREL AUDIO AL-112
    • BUZZ AUDIO REQ-2.2 ME Mastering Equalizer
    • ON THE MOON Spacecraft
    • SUMMIT EQF100 '95V. (modified)

    Macchine per caffè

    • Mazzer Mini
    • Rancilio Silvia


    • AMTEC 099 (660 ;-)) matched pair (Fairchild 670)
    • ANAMOD ATS-1
    • MANLEY Stereo Variable Mu®
    • NEUMANN U473a
    • SHADOW HILLS Mastering Compressor


      All the gear used at Jerboa Mastering is carefully selected. Some of these devices are useless on their own, but priceless in combination with other ones. All the (vintage) transformers react to the load of the next and previous boxes in line, they all have their sweet spot and their do’s and don’ts. All gear is used in certain combinations, a certain manner and a certain order: this works wonders, and makes Frederik Dejongh reach the goals he envisions.

      The next few lines are feedback by Frederik Dejongh about some of the gear he uses in his mastering set-up.


      AMTEC 099 (Fairchild 660)

      Every (mastering) engineer is always looking for his holy grail. Guess what? This is the most musical, up-to-date Tube Limiting Amplifier I’ve ever heard! It compresses the signal with a clear focus on just the right instrument in the mix. The sound is beautiful with loads of options, which makes it perfect for just about every genre you throw at it. Did I say 'beautiful sound?!' I’ve tried and tested a lot of VariMu compressors over the years, and for me, this one stands out. 


      A great hardware brick-wall and high frequency limiter. It softens the sound a little bit but moves in a very nice, musical and analogue way to the beat of a song. The de-esser, which also works in mid/side mode in the side-chain only, is great to leave the sides almost untouched or to put more focus on the sides. The de-esser is just perfect to remove harmonics from the distortion that occurs when hit hard, or to smooth out a track without losing brightness.

      NEUMANN U473a

      Great to make the mix feel more relaxed and to soften harsh highs. Great transformers and VCA sound.


      The possibilities for gain staging and drive control are endless. You can drive every op-amp or transformer in a very controlled way. Using the opto or discrete mode only for make-up can change the focus and feel of a song completely. Can vary from ‘clean with a weight’ to ‘extremely energetic’ distortion box in a matter of clicks without sounding bad. A nice tool to combine with other compressors, or just to bring out the sides in a very special way. You can work wonders with this big brother. From gentle compression to extreme limiting, although it’s not that fast. This box can transform your ‘In The Box’ mix into an ‘analog dream’.



      ARREL AUDIO ML-116 Monster Line Mastering EQ

      I can’t pin down what I like about this Italian handmade EQ by Livio Argentini, but it seems to work every time. Its patented design is free from phase distortion and other EQ artifacts. Works wonders in combination with my vintage 'Vibe' EQ's. The make-up gain is also great to drive tube gear. 

      BUZZ AUDIO REQ-2.2 ME Mastering Equalizer

      Neve 1073 meets Pultec with loads of frequentie choices and curve shapes. Can turn a sinus test tone into a beautiful song. Love it! No need to say more.

      SUMMIT EQF100 (modified)

      I call it the Pultec passive EQ with full parametric control. Smooth and adorably musical selected tubes and opamps. You can carve a song without it sounding bad, and it has headroom for years! My desert Island tube EQ: fat and gorgeous without smearing the low end and sounding dull. The most musical and beautiful mid boost you have ever heard.  Modified with personal selected tubes and even better opamps.