Interview with Strymon Design Team Member Mark McCrite on the Strymon Iridium

Interview with Strymon Design Team Member Mark McCrite on the Strymon Iridium

Hi Mark, thanks for talking with us today. We understand that you were a key player in the development of Strymon’s Iridium together with Strymon co-founder Gregg Stock. So we’d like to find out a little more about the ‘secret sauce’ that has made the product such a huge audio and commercial success.

  1. We’ve been told that Iridium’s “punch” setting is based on a 1959 Marshall® Plexi (Super Lead model number 1959). But a few different “Plexi” models existed, like the 1967, or 1959 JCM800 Super Lead (not a model with Plexi panel, but often called ‘1959’). Which 1959 was the inspiration for the tone or voicing? Is it the case that the JTM and the 800 are very different on their respective schematics?

We weren’t focused on one specific model – the schematic we used as a point of reference as we created the Punch setting was for a “Marshall 1959,” but it did not call out which specific models it was used to produce. A lot of Marshall amps use the same basic signal path with some different options, but we weren’t focused on all of the specific permutations because we planned to customize it anyway to provide more range than the original amps.

As for the specific differences between JTM45 and JCM800, schematics are pretty similar on the surface but the JCM800 puts the two inputs in series for extra gain, along with bias differences for more aggressive drive characteristics. Also, the JCM800 adds a Master Volume before the phase splitter.

  1. It seems that the “punch” setting has a much higher gain range than the 1959. What was the purpose of designing a higher gain range; did you try to cover the sonic territory covered by “Marshall Mod” amps like Soldano, Bogner and Freedman…? Hard-driven amps sometimes exhibit audible ‘power supply sag’ … was that also factored in at higher gain settings?

We were definitely trying to get into the sonic territory of higher gain amps. We did this by using our JFET front end to provide the extra gain to give you a hotter front end – but we didn’t try to replicate the architecture of the specific amps you mentioned. We do emulate the power sag at higher gain settings.

  1. What made you chose these three IR presets for “punch” ?

(i) GNR 4×12″ by OwnHammer
(Impulse of a 1971 Marshall® 1960B “basketweave” 4×12″ cab with 1971 

(ii) Celestion T1221 G12M-25 speakers.

2×12″ Vintage 30 by Celestion
(Impulse of a Celestion Vintage 30 in an open back 2×12″ cab)

(iii) Marshall 8×12″ AlNiCo by cabIR
(Impulse of a 1965 Marshall 8×12″ re-issue full stack cabinet, with Celestion T652 AlNiCo speakers)

Were they chosen to suit particular musical styles, or to recall classic tones of the 1960’s, 70’s, and ’80’s ?

We had three goals with Iridium’s internal bank of IRs: quality, classic tones, and variety. We worked with each IR vendor to get their recommendations for what would pair nicely for each amp from their respective IR libraries. Each vendor gave us a selection that showcased tonal variety with both typical pairings and some slightly more unexpected ones as well. In the end, co-founder Pete Celi – our DSP engineer/sound designer – made the final decision after a lot of critical listening based on what sounded and felt good to him while providing great variety. The A slot in each bank has a stereo IR of a typical configuration and the B and C positions provide alternate pairings – both common and unexpected – to give customers a diverse range of great sounds.

  • A number of “Can Iridium do Metal?” YouTube videos have been produced. What do you recommend if someone wants to achieve more gain on the “punch” setting?

A common way the original amps were used for higher gain was to turn the Bass, Middle, and Treble controls to the maximum to get the hottest signal coming out of the tone stack – everything full on. Another option for high gain sounds from Iridium is to crank up the “chime” setting – BASS all the way up and TREBLE at least half way up. It’s important to remember that when “chime” is selected MID control is a Low Pass filter that cuts the high frequencies as you turn it up, so keep that all the way down. If you want even more gain, Iridium gladly accepts boost or overdrive pedals in front of it.  Also, keep in mind that you can load your own custom IRs into Iridium – you may prefer other kinds of cabinets when dialing in heavier tones.

  • Do you have any recommended settings & combinations of amps/cabs for 7 string users?

That’s a broad question! It all depends on what you are looking to get out of your 7 string guitar. Many 7 string users will favor heavier sounds, and the recommendations above about using Iridium to get higher gain sounds for metal will apply here. But there’s a lot more you can do with 7 string, and for less gainy tones, including clean sounds, there are plenty of great tonalities for 7 string guitars to be found in the “chime” and “round” amps. 

Interview kindly provided by Japanese publication 'Effect Book'.

Leave a Reply

Your email address will not be published. Required fields are marked *