[1] Prior to that he was lead guitarist in the Dutch death metal band God Dethroned.

On 15 January 2009, the official announcement came that Isaac was no longer a part of God Dethroned.

More recently he has been using Ibanez Guitars, primarily his custom seven version of DN500K Darkstone, which he describes as an "Integral part of the sound of Epica".

In an interview with Moshville Uk he states that he uses a Les Paul Black Beauty and en Epiphone custom for in the studio for solos, due to their thinner necks than the Darkstone.

[2] He uses Bogner amplifiers including the Uberschall and Shiva 25th Anniversary edition and in the studio mixes his guitar sound with an Axe FX II and SansAmp.