IR stands for Impulse Response. An IR is a digital measurement of anything that has an impulse response curve (showing exponential decrease over a measurable amount of time) and this includes rooms and resonant surfaces as well. IRs are relatively simple to make, but extremely difficult to master, as there are many variables in play. Some of these variables are the same that are present when reamping: cabinet/speaker choice, power amp choice, mic choice, mic placement, mic distance, room acoustics/cabinet placement. Some of the variables are not the same as when reamping, such as: what test tone/sweep to use, how hot to send the tone to the amp, what deconvolver program to use, what settings on the deconvolver sound best, and how to cut and edit the reamped test tones relative to the raw test tone itself, whether or not to normalize the IR… These all will have an unintended effect on the accuracy of the IR profile, and not to mention that the single variable of room nodes/room acoustics becomes so much more of a problem once it’s basically one of the only things we are concerned with capturing. At Frozen Sun Audio, we are committed to providing the most honest guitar tones around, and so our reamping/IR making rig is surrounded in all directions by the highest quality acoustic treatment available, our amps are isolated from the cabinets to protect the tubes from excessive cabinet resonances, and our cabinets are decoupled from the floor, all to ensure the cleanest results.
An IR works similarly to a match EQ profile, but in a slightly different way. The most audible effect of an IR is its EQing effect, but since it is indeed an impulse response profile, that EQ effect will change over some function of time. Exactly how much effect this will have is dictated by the variables listed in the paragraph above. When everything is done correctly and all variables are controlled, we can correctly capture this changing EQ curve and model the movement of a guitar speaker!
What is a Color Spectrum IR Pack? Every Color Spectrum IR pack contains very neutral tones and more flavorful tones, as well as preset blend levels of each to allow you control over the source coloring of your guitar tracks. Each pack has its own flavor and attitude, but the IRs within those packs allow you the flexibility to dial in or out that particular attitude as you see fit.