I'm dumb, can't make my own IR

H-evolve

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Apr 21, 2014
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Montreal, Canada
So I've browsed this forum for posts on how to make your own IR, mostly interested in knowing: which channel on the amp I must use? Clean channel? Should I put the EQ all at noon? etc etc

Only thing I was able to find was "It's easy, use Voxengo Deconvolver" etc. etc.

I went the BlendIR route, from Two Notes. Quite straight forward software, however, my IRs sound like shit.

We have a Dual Rectifier + Mesa OS + SM57 setup, so we first started by reamping one track, so that we could compare with the IR when we'd have it. Track was recorded using our typical rythm tone (overdrive, channel 3, etc.)

Then, not touching anything, we used BlendIR to generate our own IR. We used the clean channel of the Dual Rec, with the EQ at noon. We put the Pres and Master at roughly the same location as the previous Reamped track. We got the Output of the amp loud enough to get the BlendIR to maximum -5dB (anybody who used it probably knows what I'm talking about).

Now with our own IR, we Reamped again the same track, but instead of using the mic'd cab, we silent recorded, using the Line Out of a Rivera Rock Crusher and our new impulse.

Comparing both tracks (with and without IR), it was very different. Not only that, but using our own IR with an amp simulator, such as Thermionik... well it sounded like utter shit. Which makes me think, we probably made a noob mistake? What did we do wrong?

Everybody says it is easy to do an IR, so either I'm dumb, either I missed a basic concept, or it's actually not that easy.

Any help would be appreciated.
 
Either impulse your actual amps settings, or connect the output to the effects return of the amp. Also, I only grab impulses once I have found a recorded tone I like, and then will grab the clean power amp-to-mic signal chain and sometimes the full signal chain. But a full signal chain will really only sound good under specific circumstances (i.e., I will do a full signal chain of my cobra, then load up thermionik serpent to play into the IR. Using other amp modeling is more miss than hit with that IR in my experiences).
 
You're going about this totally wrong. You don't go through the input of the amp.

The idea is to go into the FX return of the amp when making the impulse so you capture the power amp (with presence/resonance settings) and cab/mic sound, so you then use the FX send from the amp when playing through the impulse.

Or you can use a clean solid state power amp to make the impulse and just get the cab/mic sound, and then use a DI box between the speaker output and a cab/dummy load (be aware that you MUST use a DI that can handle the high wattage from a speaker level output to do this!) so you have full control of the amp when playing through the impulse (which is just doing the cab/mic part of the chain)
 
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You're going about this totally wrong. You don't go through the input of the amp.

The idea is to go into the FX return of the amp when making the impulse so you capture the power amp (with presence/resonance settings) and cab/mic sound, so you then use the FX send from the amp when playing through the impulse.

Or you can use a clean solid state power amp to make the impulse and just get the cab/mic sound, and then use a DI box between the speaker output and a cab/dummy load (be aware that you MUST use a DI that can handle the high wattage from a speaker level output to do this!) so you have full control of the amp when playing through the impulse (which is just doing the cab/mic part of the chain)

Well thanks, that definitely targets the basic thing I did wrong.

If I go for your first option, doing the FX Return method to create the IR, would it be that much of a problem to then use it using the Line Out of my Attenuator/Load Box? (Rivera Rock Crusher has a line out)?

I guess it'd be like having twice the effect of the power amp on top of each other, but would it sound that bad?

I'd experiment, but the Rock Crusher is not mine. (meaning I don't have it right now)
 
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Just to add, I feel like I have read that Mesa's power amps are designed in such a way that makes them more difficult to capture a good IR

I'm surprised as to why it'd be difficult to get a good IR with a Dual Rectifier. I mean, my very basic understanding is that an IR is a screenshot (more or less) of a certain setup, that is : power amp + cab + mic. So whatever gear you use to capture an IR, you'll get a screenshot of that chain, no?

Why would you capture something that is actually not a good representation of the gear? I'm definitely not an expert, but I'm skeptical about that statement you said there. I'd really be curious to get an explanation on that.
 
I have no idea why it would be different than shooting an IR of any other signal chain. Take it with a grain of salt. I am probably less versed in this than you, just saying that I remembered reading somewhere that Rectifiers were more difficult to capture for some reason or another related to the way the poweramp is on that head.
 
I have no idea why it would be different than shooting an IR of any other signal chain. Take it with a grain of salt. I am probably less versed in this than you, just saying that I remembered reading somewhere that Rectifiers were more difficult to capture for some reason or another related to the way the poweramp is on that head.

Well, I'm no expert at all! So what you say could be true, was just kinda thinking out loud, as to why it would be so.

That being said, from my little experience, I can say that Mesa amps are built in a funny way. So just because of that there might be some true in what you say.

I think it has something to do with parallel versus in serie circuitry, but they are kinda funny to play with. Dialing the Dual Rectifier of my friend proved to be so complicated, since it is not intuitive at all. You end up turning knobs that you wouldn't think affect the tone, yet they do..! Go figure.
 
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I could never get a good IR from my Triple Rectifier.
I really tried but it always sounds bad.
EVH 5153 is the same. Must be the way the power amp is voiced for the preamp.
6505 makes it easy to get a good IR
 
I could never get a good IR from my Triple Rectifier.
I really tried but it always sounds bad.
EVH 5153 is the same. Must be the way the power amp is voiced for the preamp.
6505 makes it easy to get a good IR

I can get, I guess, that creating an IR with a Mesa Dual Rec would be difficult to use afterwards with another preamp, or another amp sim. However, when doing an IR with the power amp or a Dual Rec and then using that IR to play the same Dual Rec preamp, I really fail to understand why it wouldn't work.

Meaning, I can understand (partially) why it wouldn't work with another preamp or any random preamp/preamp sim, but with the exact same preamp it was designed to work with, it should work, doesn't it?
 
Assuming that making IRs with a power amp and you have to use a preamp with IRs is plainly dumb. IR is frequency response + reverb and NO SATURATION what so ever.
You still will have better sound using power amp included in simulation or amp recording. Catharsis Fredman IRs was made with a power amp, yet everyone used them without disabling power amp in the signal chain and everyone loved it.
 
Assuming that making IRs with a power amp and you have to use a preamp with IRs is plainly dumb. IR is frequency response + reverb and NO SATURATION what so ever.
You still will have better sound using power amp included in simulation or amp recording. Catharsis Fredman IRs was made with a power amp, yet everyone used them without disabling power amp in the signal chain and everyone loved it.

To me there is still some logic behind bypassing the power amp (using FX Send, considering you use the IR with a real amp), so it's definitely not "dumb". Debatable, perhaps yes, I'd agree with you on that one.

But, making an A/B comparison last weekend, I preferred when the power amp was bypassed. Both sounded good, but I preferred the FX Send test we did.

And also, we did achieve to do a "decent" IR with a Dual Rectifier Power section. Was actually quite close to the Rosen Digital IRs. Just needed a bit of correction in the low mids (below 700 to 1.5 kHz if I remember this right).