My first FF IRs (EVM12L)

Why face up? I believe that to get a reflection free IR, you need to in effect remove walls and ceiling from the recording (hence why the mic should be placed on the floor). If the cab were face up (presuming the mic is suspended in the space above it), this would be no different from placing the cab against a wall indoors.

Because I can place sound absorbers and deflection behind the cab such that no boundary reflections will reach the mic within the desired time window.

This is impossible to do in my live room. 24x34x13.

Richard
 
The entire process of capturing a FF IR is fascinating. Nowhere is a definitive, complete guide to be found, only broad stroke suggestions. At least based upon my searchings of the past several days. However, I do have my questions slimmed down considerably.

For the impulse, the suggested method is to use a log sine sweep; single? Duration (how quickly/slowly)? It would seem the Axe utilizes several quick sweeps (only a second or so for each). Still unsure if all silence before the captured response should be removed prior to deconvolving.

For a FF, a large room is suggested, with the cabinet placed in the center. This is to eliminate ERs and other room nuance. I am curious about gobo use, so this will be an area I will be experimenting with. I am curious to discover if, with my non-optimal room dimensions, my room treatments (especially the bass traps) have provided for the lack of "girth" in my initial captures, or if it was simply a matter of technique.

I am also in search of a ~2m FF IR that, singly, satisfies my ear. Thus far, I have been unable to find one. I have always preferred "my tone" over others when it is a rig I play through. I am wondering if, then, such an FF IR would thus need be of my personal favorite cabs? I am going with a "Yes!" on that one, but much like I find inspiration in other's gear, so might I find direction in other FF IRs. I would love to try some of Jay's FF IRs that he personally feels are "great."
 
There are 2 of Jay's IRs that I use, singularly in mono lorez, in almost all of my presents (which are usually amp+cab and thats it). To me they sound absolutely phenomenal on their own, and I hardly need to touch the amp block when either of them is selected. These are a 2x12 Gold+G12-65 30 degrees, and one he posted in the thread 'a blackface kinda thang'. I would highly recommend tracking these down (they're both uploaded somewhere) for a great single IR experience. IMHO they are both far better than any of the cabs in the axe2, or any other 3rd party IRs I have tried, for any amount of gain.
 
Still unsure if all silence before the captured response should be removed prior to deconvolving.

I believe that silence in front of an IR simply adds delay to playback, and effectively shortens the length at the end of the IR due to the strict 1024 or 2040 point IRs in the axe (resulting in the auditory equivalent of a lower resolution IR). This shouldn't matter so much in hirez mode, although a hirez FF IR would be more difficult to capture, without audible benefit.
 
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Log sweep, I would use 10 second sweep.

In the space you are using you will get reflections in your resulting IR.

You don't need to remove dead silence before deconvolution, but you sure have to remove it after the deconvolution process. Locate the first peak in the deconvolved IR, a few samples before it is where the IR should start (which should be close to 0). Don't apply minimum phase transform, as it destroys the phase information of your captured IR.

From Jay in the old forum:

Jay Mitchell said:
Here's the simplest procedure to get realistic-sounding IRs:

You need enough floor space in the test area to place the speaker and mic 2 meters apart, with no reflections that will arrive less than ~20 ms after the direct sound from the speaker. Practically speaking, this requires a room that is ~8.1M (26 1/2') x 6.1M (20') or larger. The speaker and the mic should be placed near the center of the floor space so as to maximize the reflection-free zone.

Place the mic on the floor. Ideally, it should be a hard surface. If you have carpeting, use large sheets of cardboard to make a reflective surface that surrounds the mic and speaker, which can also be on the floor. I usually take IRs at 4 angles: on axis, 15, 30, and 45 degrees off axis. You can easily mark positions on the floor (or cardboard) so you can quickly move the mic.

With the mic on the floor aimed at the speaker, the reflection from the floor that will also be part of the measurement arrives so soon after the direct sound that its only effect is to add 6dB to the level the mic sees. Since there will be floor reflections added by a player's rig, this is the best way to get the sound of the cab you're measuring. However, there's a trick I use to get a "bonus" cab: place the mic off axis of the speaker, about a meter off the floor, and the floor reflection adds the effect of an virtual "image" cabinet that is located under the real one, below the floor. In this way, you can use a 2x12 cab to get the IR of a 4x12 with the same speakers in it, and a 4x12 can produce the IR of a full stack.

The test signal that will yield the best results under less than ideal conditions (e.g., nonzero environmental noise) in the shortest time is a swept sine. Specifically, I recommend a log sweep for IR acquisition. Send the signal to the speaker at a healthy level, and record the mic output. Then use a deconvolution routine to process the recorded sweep to produce the IR.

The entire process of capturing a FF IR is fascinating. Nowhere is a definitive, complete guide to be found, only broad stroke suggestions. At least based upon my searchings of the past several days. However, I do have my questions slimmed down considerably.

For the impulse, the suggested method is to use a log sine sweep; single? Duration (how quickly/slowly)? It would seem the Axe utilizes several quick sweeps (only a second or so for each). Still unsure if all silence before the captured response should be removed prior to deconvolving.

For a FF, a large room is suggested, with the cabinet placed in the center. This is to eliminate ERs and other room nuance. I am curious about gobo use, so this will be an area I will be experimenting with. I am curious to discover if, with my non-optimal room dimensions, my room treatments (especially the bass traps) have provided for the lack of "girth" in my initial captures, or if it was simply a matter of technique.

I am also in search of a ~2m FF IR that, singly, satisfies my ear. Thus far, I have been unable to find one. I have always preferred "my tone" over others when it is a rig I play through. I am wondering if, then, such an FF IR would thus need be of my personal favorite cabs? I am going with a "Yes!" on that one, but much like I find inspiration in other's gear, so might I find direction in other FF IRs. I would love to try some of Jay's FF IRs that he personally feels are "great."
 
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Thanks for the tips!

Tried to capture some impulses without the Axe today, but it was such a frustrating adventure that I am taking a break until tomorrow. I could not find a good 24/48k log sine sweep of ~10sec, and do not have anything to create one. Voxengo Deconvolver has a generator, but no option to select lin or log. Since I had no other (immediate) option, I just created a 10sec wav. Unfortunately, I had no idea Axe-O-Matic was a 48k only wav file process, so I had to redo stuff. So many new questions popped up as I was doing this stuff, and as I sat screaming obscenities over the lack of detailed information, I was somehow able to refrain from throwing heavy objects. Sidenote: I LOVE.. absolutely LOVE!!!.. throwing phones. Cordless home phones are particularly satisfying. :D

My neighbors must be completely and utterly disgusted with me. Cosmic comedy? I am unable to get ot their front door to ask if they will mind if I make some noise for about 20 minutes or so. I would have no problem working around their schedule. But, I cannot reach their door, and I will not sit in the rain for hours waiting for them to come outside, home, etc. lol... what a bad day...
 
Thanks for the tips!

Tried to capture some impulses without the Axe today, but it was such a frustrating adventure that I am taking a break until tomorrow. I could not find a good 24/48k log sine sweep of ~10sec, and do not have anything to create one. Voxengo Deconvolver has a generator, but no option to select lin or log. Since I had no other (immediate) option, I just created a 10sec wav. Unfortunately, I had no idea Axe-O-Matic was a 48k only wav file process, so I had to redo stuff. So many new questions popped up as I was doing this stuff, and as I sat screaming obscenities over the lack of detailed information, I was somehow able to refrain from throwing heavy objects. Sidenote: I LOVE.. absolutely LOVE!!!.. throwing phones. Cordless home phones are particularly satisfying. :D

My neighbors must be completely and utterly disgusted with me. Cosmic comedy? I am unable to get ot their front door to ask if they will mind if I make some noise for about 20 minutes or so. I would have no problem working around their schedule. But, I cannot reach their door, and I will not sit in the rain for hours waiting for them to come outside, home, etc. lol... what a bad day...

You can use glsweep from DRC to generate the log sweep and SOX to convert the raw pcm file to a wav

DRC: Digital Room Correction
SoX - Sound eXchange | HomePage

I generated 10 sec and 20 sec log sweeps for you here:
Index of /sweeps
 
I am unable to get ot their front door to ask if they will mind if I make some noise for about 20 minutes or so. I would have no problem working around their schedule. But, I cannot reach their door, and I will not sit in the rain for hours waiting for them to come outside, home, etc. lol... what a bad day...
I once looked for a solution to know when my neighbors are out, without it being too much hassle for them. I didn't buy that stuff yet, but you could probably do it with some wireless light switches. My question for them would have been to put the on/off button near their door and get used to pressing it, just like an alarm :D On my side, I'd stick one of these very energy friendy led like things in it. You would however need a remote that indicates the status to them or give them a second unit for them to doublecheck. They can also put it to "green" when they are home and can handle some noise anyway, or put it to "red" when they for once would like some quiet, even if it's not very late yet (e.g. when they're sick).
I would go for a model that doesn't radiate EMF all the time (like a DECT phone does). I hope these things don't. It's time I look into this again, cause I'd sure like to make some serious noise more :D My worry is that they will misuse it to try and shut me up though, when it's not even 22 PM :p
 
You can also use SoX to resample at 48 k if needed. Generally it is best to just work at 24 bit - 48 k since that is what you need to end up with for the AxeFx. I agree with AlbertA WRT min phase; IMO it is even more important when working with FF captures to preserve the phase information.
 
Thanks again for all the help :D
And Albert- I did not piece together you and the IR Converter (uh, duh on me, right in your sig!). Going back through Jay's, yours, and others' posts on the old Fractal board I found more information. My better half will be speaking to the neighbors tomorrow, and then we are going to work on making the big room get as close as possible to being a viable option. It will not be perfect, but hopefully something decent enough I hope. Shy of that, I have the go ahead to begin the search for a local studio that I can bring my cabs to and have the physical help I require to get these IRs.

After some very serious time spent with the Axe, power amps, cabs, and monitors, it is so very apparent that a primary aspect of my dissatisfaction lies with IRs. If I use the Axe with a *transparent* amplifier and my two favorite cabs (if I had to choose one, it would be my Greenback 2x12; one Greenback in particular is magical. Or maybe the EVM12L cab...), I am quite happy. But, through my studio monitors (Blue Sky System One 5.1), no go. Flipping between the two made it incredibly, starkly obvious. I figure if I have a decent set of IRs of my cabs... :D The Greenbacks are first :D
 
Hmm... a little browsing, and I stopped by the Redwirez site. They have a Marshall 4x12 Celestion G12M Greenback loaded set, which their "IR Matrix" lists as including five FF TC30 IRs. While I would prefer a 1x12 (yes, even over my 2x12), I am quite tempted to try these. After all the reading I have done now though, I am a bit sceptical. Shy of someone piping in, only one way to find out, eh?
 
Hmm... a little browsing, and I stopped by the Redwirez site. They have a Marshall 4x12 Celestion G12M Greenback loaded set, which their "IR Matrix" lists as including five FF TC30 IRs. While I would prefer a 1x12 (yes, even over my 2x12), I am quite tempted to try these. After all the reading I have done now though, I am a bit sceptical. Shy of someone piping in, only one way to find out, eh?

that's the free/demo cab, right?

Red Wire Impulse Responses | Free guitar speaker cabinet IRs
 
There's quite some consensus that the Red Wirez FFs do not work well as all-in-one / standalone farfield IRs.
Using them makes your sound disappear in the mix. Mixing them with other IRs is another story of course.
 
Ahhh, yes. Funny thing is... the one mic I am most interested in, the TC30, is absent from the freebie :( I will be buying the full version later today. Jay's FF IRs are incredible. All of the other FF IRs I have heard sound as anemic as mine. Maybe I have not sampled the better ones? Depending on these, I might grab one of the 15" bass cab IR packs.
 
Yek, Yek, Yek... lol.. the torture!!! I lay here stuck in bed for a few hours more before I am able to try this out!!! I am honestly debating the merits of swapping out the current quad in my Legacy for the stock tubes for comparison. "No way!" is winning though, as I should be able to sculpt the Axe version to get damn close I think. I hope :D The real test is going to be the accuracy of responsiveness with the MV. Though I will be unable to imitate my dual MV mod (Pre and Post PIMVs), the stock MV in a model that I can run up around 6-7 (sweet spot, IMO) without killing small animals would be... glorious :D (mmm... roemrijk?)
 
Not my day it seems...

I tried the Redwirez G12M IRs out that I bought. My main reason for buying the full version of the otherwise free cab was to try the FF IRs. I will need to spend more time reading and listening, but upon a first listen, they sound more similar to what I have done than what Jay has done. Jay's are the only ones that even come close to the fullness and general experience of sitting within a couple meters of a cab while just fiddling about on guitar. Everything else is incredibly anemic to my ears.

That said.. after playing with my Greenback loaded 2x12 for the past to days, going to a studio monitor + IRs environment is... saddening. IRs are truly lacking for me, and in a MAJOR way (so far.. I hope). Ver5.04b had significant changes as well, and I am pretty split on my feelings there as well (all was fine.. unit I "reset" each amp in my favorite patches by doing the "switch to another amp and back" thing). Some days I wish I were normal... I will keep my piss-poor mood away until I can socialize again with a more positive attitude.. this mood will serve no one in any manner.. (sigh)...
 
You may like the OwnHammer FFs that are coming out soon. I've been beta testing the first set and they are quite different, and in my biased opinion, better than the RWs.
 
Really not my day..

I recorded nine captures using the 10sec log sine sweep Albert provided (thank you so much again!!!). I stopped recording before the entire sweep file completed playing (but a bit after the final bit of 20k had a chance to decay) for most of my captures, so when I tried to Deconvolve with Voxengo.. "Recorded file cannot be shorter than the test tone file!" error. Cool, nice to know, my bad. I have three that are longer than the test tone file, so I go ahead and Deconvolve them. The resulting file is... it looks like slammed audio, and there is no silence at the start or end (there should be). I know it will likely not work, but I go ahead and Axe-O-Matic them, and.. no audio passes with any of the three loaded as a cab IR.

No clue what I did wrong. Cubase is a pure and absolute PITA for editing and saving edited files. I truly miss PT.

EDIT TO ADD:
I went ahead and threw the nine captures plus the sweep into this folder on my site. If someone finds time to try and get it to work, I would really appreciate the help. I am stumped. Cubase song was set for 24/48k, so my recordings are 24/48k. Should be good to go for Deconvolver, and then Axe-O-Matic. If someone figures it out, please let me know what I missed? We actually cleared most of the room out to do this today, and waited until the neighbors went out for the evening.
 
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You may like the OwnHammer FFs that are coming out soon. I've been beta testing the first set and they are quite different, and in my biased opinion, better than the RWs.
Are they full like Jay's? Reference mics? Floor shot, plus off floor? Greenbacks?
Last time I checked OH's site, there were no Greenbacks. The other thing is that both OH and RW seem to prefer 4x12 cabs. If I had the cash, I would be grabbing some 1x12 boxes, trying them out with my speakers to figure which I like, and then having them lugged down to a local studio and spend several hours shooting IRs of each cab. With the RW pack, there were only nine TC30 IRs, and none of them were really usable for my needs/wants. This is why I have been cursing my ears and tastes all day today.

I am not overly fond of the OH EVM12L IR that is stock in the Axe-Fx II. I find it a bit bright, and missing that.. "EVM Vowel" sound. Not sure how to explain it...
 
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