AMP+CAB IR Pairing!

[tommyzai]

AMP+CAB PAIRING: Some amps are packaged with cab IRs, but most are not. Aside from A/B-ing through thousands of IRs, is there a way to match amps and cabs to get a complimentary sound (I realize this is subjective) and avoiding the dreaded aliasing or other incompatibilities? Would pairing amps and cabs based on the hardware model configurations be a good way to go? How do you pair-up amps and cabs?

[BertKoor]

[...] avoiding the dreaded aliasing [...]

Care to elaborate on that? Have you experienced any?
Because aliasing is an artifact of resampling. So unless the IR is of a different sampling rate than what you run the project in, that should not happen.

[tommyzai]

[...] avoiding the dreaded aliasing [...]

Care to elaborate on that? Have you experienced any?
Because aliasing is an artifact of resampling. So unless the IR is of a different sampling rate than what you run the project in, that should not happen.

I have not noticed any aliasing in my limited demoing, but there are many reports of this . . . especially when combining multiple slots, i.e., pedal, amp, cab. Perhaps lower sample rates or mixing sample rates are the cause . . . I don't know.

[Uncle E]

Pairing an amp with its associated cabinet isn't necessary. These things aren't 100% accurate, anyway. I usually just find an IR that doesn't have any harsh peaks and run all my Tonex captures through it.

What's more important (for me, anyway) is to run a super short room reverb after it. This is what makes the UAFX pedals so convincing, the room reverb they have built-in. Makes you feel like you're in the room with an amp.

[CapnLockheed]

Really very little difference between hardware and amps & cabs IMHO. It's really just a matter of which pairings sound good together to YOU. AND which best serve the song if being used in a multitrack recording. The only rules is that there are none. What constitutes "good" tone is HIGHLY subjective.

[lunardigs]

Very true.
That said, I really like 2x12 IRs and British amp sims lately. In fact, I tend to like 2x12 IRs better than 2x12 cabs in real life. Meanwhile, 4x12 IRs don't sound better to me as compared to the real thing. Mind you, I mean this as it's reproduced through my studio monitors.

[imrae]

A simple IR cabinet model is totally linear, so aliasing has nothing to do with the cab sim. I know there are cab sims out there which claim to go beyond linear IR but I don't see how this can be an improvement really.

I think it's helpful to think about the cabinet response as a product of two separate shaping stages: a set of sharp resonances and some broad frequency shaping. The resonance is mostly determined by the shape of the cabinet (and possibly its placement in the room) whereas the broad shaping can be tuned by changing the microphone, microphone position, speaker cone, amp EQ settings and post-EQ. (The microphone and speaker cone might also bring some resonant peaks of their own, but that should be quite subtle. Maybe there are some guitar experts here who can give examples of where it is significant?)

In terms of matching a complementary cabinet to head, this will mostly be about the broad shaping. If you have a high-gain amplifier with a tubescreamer in front of it, the raw amp signal is very bright and would usually prefer a dark cabinet (e.g. Marshall 4x12 with vintage 30s) and/or with a big low-end that compensates for the low cut (e.g. Mesa oversized). A cleaner amp might have a darker natural sound and expect a brighter cabinet - but have a listen and check!

The resonances on the other hand are where a lot of the "character" comes from. If you use a cab IR with some really cool-sounding resonance you may find it builds up obnoxiously if used on a lot of tracks. Different cabs spread in stereo with broad EQ to match the overall shape can give something that sounds very wide but balanced. On the other hand, if you run some different distortion sources (maybe a preamp sim and a fuzz pedal) through the same cab resonance they will sound more convincingly like the same instrument.

I really like the MCabinet plugin because it follows this separation; you can "learn" a flat profile with resonance from a directory of IRs in different mic positions (or just one IR, it doesn't make that much difference...) and then EQ/filter in the overall character you want for mix balance purposes. But you can have a similar workflow with any IR loader; just pick one reasonably balanced IR for each cabinet, and be ready to do a bit of EQ work to get the rest of the way. Include some compensating EQ when you A/B different options, so you can hear the resonant effects separately from the overall bright/dark/tight/boxy character.

[Uncle E]

I know there are cab sims out there which claim to go beyond linear IR but I don't see how this can be an improvement really.

Guitar speakers sound different at different volumes.

[CapnLockheed]

I know there are cab sims out there which claim to go beyond linear IR but I don't see how this can be an improvement really.

Guitar speakers sound different at different volumes.

That's also very true. IRS of one cabinet can sound very different depending on many variables. Volume, mics used, room acoustics....etc. That's probably why many of the commerical libraries available often contain many impulses of the same speaker.