Founded by John Petrucci, guitarist and founding member of prog metal band Dream Theater, Tonemission recently released a set of impulse responses (IRs), the John Petrucci IR Collection: Vol 1. Created by Petrucci and his long‑time engineer James (Jimmy T) Meslin during the recording of three albums (Petrucci’s solo Terminal Velocity, Liquid Tension Experiment’s LTE3 and Dream Theater’s A View From The Top Of The World), this four‑pack collection gives guitarists access to the sound of Petrucci’s amplifier recording chain, from guitar cabinet (a circa 2018 Mesa Boogie Standard Recto 4x12 fitted with Celestion Vintage 30 loudspeakers) to DAW input, as recorded during the sessions for those albums.
The collection’s three main packs, Terminal, Liquid and Dreamworld, are named after the sessions during which they were created. The fourth pack, zBonus Cabinets, contains captures of three further Mesa Boogie cabs (a 1x12, a 2x12 and a 4x12), which were taken during the Terminal Velocity sessions. Each pack contains two folders: Assets, which contains IRs created from captures made via the individual mic and preamp combinations used to record Petrucci’s Recto 4x12 on that particular album; and Blends, where you’ll find IRs that were created from captures made from the mixes of the cab/mic/preamp combinations that were blended and EQ’ed as part of producing the actual rhythm and lead guitar sounds on those albums. In total, the main packs offer 13 individual cab/mic/preamp IRs and nine ‘album‑accurate’ Blends, with the zBonus pack adding another nine IRs and three blends. All IRs in the collection are 100ms long and come in 16‑ and 24‑bit formats at 44.1 and 48 kHz, and in 24‑bit only at 88.2 and 96 kHz.
Here you can see some of the mics used in the album recording sessions during which these IRs were captured.The microphones used during the sessions were a pair of Mojave MA301 large‑diaphragm FET capacitor microphones covering cardioid close‑mic and omni room‑mic duties, with supporting appearances from an Audio‑Technica ATM450 side‑address cardioid condenser; Royer R121, Shure KSM353 and sE Electronics VR2 ribbons; Shure SM7 and Sennheiser MD 421 dynamics; and a rather unusual choice, the dual‑element (dynamic and electret capacitor), dual‑output Audio‑Technica AE2500 kick‑drum microphone.
Although there are no details of which mic passed through which preamp on which session, the choices (RND Shelford Channels, RND Portico 5024 Quad Mic Preamps and Black Lion Audio BL12A half‑rack, American‑style preamps) point to a definite penchant for classic console sounds. The mic preamps’ outputs were sent to the inputs of a Phoenix Audio Nicerizer 16 MkII Class‑A summing mixer, whose channels were set up panned hard to the right, then mixed together into its left output using the mixer’s pan controls to create the blended guitar sound. The mono signal from the left output was then split to feed both channels of a JDK Audio EQ‑R24 dual‑channel parametric EQ, the left channel of which was used to optimise the rhythm guitar sound and the right channel to sculpt the lead sound.
In use, the Petrucci IRs work like any others, though when used with Positive Grid’s Bias Amp 2 and Bias FX2 I discovered that the filenames exceeded that software’s 20‑character limit, and a ‘+’ sign in the Terminal pack’s Blend file names triggered a format error message. A quick bit of filename editing solved that!
It was an object lesson in utilising and exploiting the different responses and nuances within multi‑mic setups.
Using Bias FX 2’s emulation of John Petrucci’s signature Mesa Boogie JP‑2C to drive his blended rhythm and lead IRs in an attempt to recreate his guitar sound precisely wasn’t entirely successful — I’d need a different guitar, a real JP‑2C and a Mesa Boogie Cab Clone at the very least to do that! But I did manage to create reasonable approximations of the effects‑heavy cleans, the tight, dry rhythms and the smooth, saturated lead tones that, to my mind, characterise his sound. Of course, this collection isn’t all about mimicking Petrucci’s sound, and mixing and matching different captures from within and across the four packs using the Libra Ignite plug‑in to create my own blends was an inspiringly creative experience. It was an object lesson in utilising and exploiting the different responses and nuances within multi‑mic setups. An added plus was that the stock 1x12, 2x12 and 4x12 blended IRs in the zBonus pack worked gloriously in my Strymon Iridium pedal when paired with its onboard Deluxe Reverb, AC30TB and Plexi‑based amp sims.
As far as I can ascertain, the John Petrucci IR Collection: Vol 1 is the first IR offering to contain IRs created directly from captures through a speaker cab to DAW signal chain, as recorded during actual album tracking sessions. Although you can use these IRs to try to sound like John Petrucci, if you are into the sound of a Mesa Boogie Standard 4x12 Recto cab you’ll find this carefully curated IR collection to be a versatile and inspirational companion on your musical travels.