Anyone Want to Test This Beta Firmware

[javajunkie]

Yep, I was speaking in general to the "perfection" argument. Same would apply to a cab. Move the cab 3" to the left in the room it's being captured and it will sound different. There are a million variables.

And this technique eliminates one of the variables and only if you wish it to do so.

 

[erockomania]

And this technique eliminates one of the variables and only if you wish it to do so.

agreed

 

[erockomania]

If realism is the goal then its definitely a better outcome.

not necessarily as you can likely just dial the amp to come to the same conclusion, albeit faster or slower depending on what you are after. This just gives you a different starting point.

Don't get me wrong, I like the option, I just know this is going to become an "uncompensated IRs suck" discussion in a month, lol. It's clearly not the case.

 

[Speculum Speculorum]

Everybody tried their best to enjoy the music show, despite the fact that the band wasn't using "Compensated IRs".

 

[javajunkie]

in that one example, maybe. get any nice IR made with quality gear over the last 5 years and it could be better or worse. This is not automatically a better outcome... it's simply different. A different EQ applied to the sound.

Maybe create an IR to compensate for the room the IR was captured in is next... then it will be the true sound of the cab, unaffected.

All you need to eliminate the room is have a big enough space so the reflections don't return by the time the IR is captured. Before the Ultra-Res that was pretty doable, Ultra-Res would need a pretty big room.

But we are not talking about room here. We are talking about capturing frequency altering circuitry that may not be intended. The great thing is, if you do not like it, you don't have to use it.

To put it in perspective, when you are micing the amp to get capture you want, you are not hearing the poweramp coloration. So when you capture it, it is not the same frequency response as when you set things up.

 

[erockomania]

All you need to eliminate the room is have a big enough space so the reflections don't return by the time the IR is captured. Before the Ultra-Res that was pretty doable, Ultra-Res would need a pretty big room.

But we are not talking about room here. We are talking about capturing frequency altering circuitry that may not be intended. The great thing is, if you do not like it, you don't have to use it.

The room will also alter what is captured is my point. Maybe more-so depending on the room. Just applying a little balance to the situation is all.

Folks are stating this will create a perfect IR of the cab when that is not the case. Getting there, for sure.

 

[Speculum Speculorum]

Yeah - there are so many more variables to getting a good sounding IR than whether or not you compensated it. In a pro setting it could definitely be used to up the ante on quality, but it's not like BAM! Your IR now sounds exactly like a cab!

That's not the way IRs work, currently. A dynamic processing IR is going to be necessary to get us to the next step in modeling.

 

[erockomania]

To put it in perspective, when you are micing the amp to get capture you want, you are not hearing the poweramp coloration. So when you capture it, it is not the same frequency response as when you set things up.

Yup, I get it. And that makes sense. You are at least hearing the room during this process.

 

[Stratoblaster]

And this technique eliminates one of the variables and only if you wish it to do so.

Yes, exactly true in both cases. Reducing and isolating the sonic contribution of a particular element in the signal chain is the goal here, and if a players likes the sound of an uncompensated IR and chooses to use it that's cool too. For myself, I like to have the variables reduced and sonic effects totally isolated to the appropriate element/function.

 

[erockomania]

Will the quality of the "correction DI" have anything to do with the compensation? I've had some folks message me about this on FB and the DI box was mentioned as a glaring weakness that could potentially create poor correction that might be further off base than a high quality SS amp. I do not know how ciff is doing the correction but I'd imagine if something like the Suhr box was used (which has a 300hz low cut) then the correction might be totally wrong.

Thoughts?

 

[Rex]

Will the quality of the "correction DI" have anything to do with the compensation? I've had some folks message me about this on FB and the DI box was mentioned as a glaring weakness that could potentially create poor correction that might be further off base than a high quality SS amp. I do not know how ciff is doing the correction but I'd imagine if something like the Suhr box was used (which has a 300hz low cut) then the correction might be totally wrong.

Thoughts?

We're talking about correcting errors that could be 3 dB or larger. Any DI error is going to be much smaller than that. What's the source of your information that the Suhr box cuts off below 300 Hz? That kind of low cut would make the device useless for anything guitar-related.


You asked for thoughts. I think you're spending a lot of energy on theoretical reasons why this might be pointless or suck altogether. Yet those who've tried it report improvements in sound, so pointlessness and suckage aren't involved.

 

[J.C]

"I'm quite possibly not impressed" said the man with his arms folded.

 

[erockomania]

We're talking about correcting errors that could be 3 dB or larger. Any DI error is going to be much smaller than that. What's the source of your information that the Suhr box cuts off below 300 Hz? That kind of low cut would make the device useless for anything guitar-related.


You asked for thoughts. I think you're spending a lot of energy on theoretical reasons why this might be pointless or suck altogether. Yet those who've tried it report improvements in sound, so pointlessness and suckage aren't involved.

I was off today and the whole theory was interesting to me

My original point still stands... this is just another means to the same end for most people. It is a more accurate base from which to start but might ultimately have the same tonal outcome. Folks probably won't get "better" tones and I'm afraid that will be misunderstood. Then again, I could be completely wrong and if I am, then I still win because my tones will improve This is about the end tones to me... that is all.

I get that folks want a more "true" or accurate IR. Makes complete sense. Then I got a couple messages about this topic(because folks see my posts here and know me on Facebook), and specifically, the issue with the DI boxes... the Suhr in particular(one guy thought the Suhr was particularly bad in this situation as he's done tests and found a 300hz drop, and I trust him)... and the potential for them not to work as intended in this application. I felt like it was worthy of discussion if "true" or accurate is what you are after. This is healthy discussion and I've been civil the whole time, as have you. I'm not trying to be a dick... I simply like to remove any potential misunderstandings. I'm not trying to disprove anything, I'm trying to find answers... well, that satisfy me (not that I'm entitled to be satisfied). I appreciate your answers, really.

Regarding my energy... it's is well spent as I have a better understanding of this now

 

[Rex]

I know you're not being a dick. You've been a gentleman throughout.

I've seen two common themes in Fractal's products:

1. Strive for accuracy.
2. Allow users to depart from that accuracy in controlled, repeatable ways.

The new IR capture method is on the "strive for accuracy" side of the equation. You're right: in compensating for past inaccuracies, some folks may have approached a goal similar to what they'd go for with the more accurate method. It's doubtful that they've achieved that 100%; it's just about impossible to accurately duplicate an impedance curve using EQ. As for the Suhr DI, if it's rolling off below 300 Hz, something is wrong. Even the cheapest DIs are usually flat and reliable.


The most meaningful question, IMO, is this: Do you prefer the results you get using the new method?

 

[Morphosis]

At the end of the day, it`s all about frequency response / EQ curve. So again, what influence this curve? The Power Amp (interacting with the speaker cabinet -> speaker resonance), the cabinet, the room, the mic, the mic position, the mic preamp.

"Perfection": Subjective term. (What sounds best to you?!)
"Accuracy": Objective term. (How identical is copied "B" to actual reference "A"?)

So, what does this mean, when it comes to IR-Capturing with OR w/o reference IR?

Capturing & creating a IR of a actual speaker cabinet is in fact always a result of subjective behaviours. Why subjective? Well, lately when it comes to mic.-placement the IR creator have to decide on subjective preferences where to place the mic in front of the cabinet. Finding a "sweet spot" is - for sure - finding the place, where a given sound source monitored through the mic sound "perfect".

Monitoring through the mic and find a "sweet spot" can`t be done without amplification! This means: If you`ve found the subjective "perfect" "sweet spot", resulting in a objective dedicated frequency response when capturing this as IR, you also capture the influence of the actual used Amp (which response unlinear as long as it has NO infinite high damping factor).


SHOWCASE A: Capturing a cabinet with the actual Tube Power Amp by monitoring through the real Amp

As long as you audition the mic.-placement, monitoring the sound and capture the IR through an actual Guitar Amp (let`s say a Deluxe Reverb) the introduced "reference IR tecnique" does make sense, if the target is "accuracy". Why? Because you will get rid from the influence of the Power Amp of the actual Amp. Why we want exclude the Power Amp? Because when using the captured IR in the Axe-Fx, the Axe-Fx Power Amp Sim will recreate the actual Power Amp. So "accuracy" of the IR means: All influences the Axe-Fx models shouldn`t be in the IR. What should and MUST be in the IR: Speaker cabinet + mic + mic.-placement + mic preamp. Exactly THIS is the particular signal-chain represented by the Cab-Block. Nothing more - nothing less.

So end of the accuracy-story? Perhaps, but only, if the speaker resonance of the actual cabinet is "accurate" represented in the Axe-Fx speaker tab. So, IMHO the "new" reference IR signal chain (measurment of the power Amps influence from it`s speaker line out (or DI line out of the speaker out) would be the most feasible point of the signal chain to measure the actual speaker resonance. If you plot this frequency curve you have the data to setup the Axe-Fx speaker tab more accurate to the actual used IR!

WISH: Don`t use the "reference IR signal chain" only for compensting the Power Amps influences, but also use it as measurment point for the speaker resonance of the actual Cab! Save this data besides the IR data in the CAB-IR and link it to the Amps Block speaker tab for auto adjust this page to the actual used IR! If we talk about accuracy, THIS WILL FIX THE STILL MISSING LINK TO REALITY!


SHOWCASE B: Capturing a cabinet with a certain Power Amp by monitoring through an Axe-Fx Amp-Sim

This is different from A! We now getting into a conflict between "accuracy" and "perfection", if we monitor via Axe-Fx Amp-Sim sound:

Remind:
Monitoring through the mic and find a "sweet spot" can`t be done without amplification! This means: If you`ve found the subjective "perfect" "sweet spot", resulting in a objective dedicated frequency response when capturing this as IR, you also capture the influence of the actual used Amp.

Because we USE IN THIS CASE the Axe-Fx, including it`s Power Amp Simulation, we won`t substitute any real Amp with the Axe-Fx Power-Amp Sim.

So, if we NOW subtract via reference IR non-linearities resulting from the actual used Power Amp we subtract something from our subjective "PERFECT" IR (we monitored when finding the sweet spot) to get a more objective "ACCURACY" IR (because we want get rid of the Power Amps influence the Axe should model by itself standalone).

Something's got to give? Probobly not, if we can combine "perfection" with "accuracy"!
If there would be a way to capture a inverted reference IR by itself and we could put this IR (which will equalize the audible power amp influences) into the signal chain WHEN MONITORING THE MICED SOUND to find the "perfect" "sweet spot" and capture THIS result as a IR including reference IR tecnique, the resulted IR would represent both: "subjective perfection" & "objective accuracy"!

WISH: Make it available to capture the "reference IR chain" by itself, resulting in a inverted frequency response IR. This could be useful to equalize Power Amps non-linearity, when audition Axe-Fx with the dedicated Amp.

 

[corpsetopheros]

hey there! having shot an ir i really like a while back, can i capture only the response of the power amp and then use it to compensate my old ir?

 

[Suhr]

In to what load? What db?

Can you give me specifics of this statement? What scenario are you seeing this? How many dB? What is the loads impedance?

If you tell me the load you are driving in to I'd be happy to give you the actual test results.
All transformers will have a roll off depending on the load directly related to the cost and size of the transformer.
In most practical situations it is moot.
Thanks
John

I was off today and the whole theory was interesting to me

My original point still stands... this is just another means to the same end for most people. It is a more accurate base from which to start but might ultimately have the same tonal outcome. Folks probably won't get "better" tones and I'm afraid that will be misunderstood. Then again, I could be completely wrong and if I am, then I still win because my tones will improve This is about the end tones to me... that is all.

I get that folks want a more "true" or accurate IR. Makes complete sense. Then I got a couple messages about this topic(because folks see my posts here and know me on Facebook), and specifically, the issue with the DI boxes... the Suhr in particular(one guy thought the Suhr was particularly bad in this situation as he's done tests and found a 300hz drop, and I trust him)... and the potential for them not to work as intended in this application. I felt like it was worthy of discussion if "true" or accurate is what you are after. This is healthy discussion and I've been civil the whole time, as have you. I'm not trying to be a dick... I simply like to remove any potential misunderstandings. I'm not trying to disprove anything, I'm trying to find answers... well, that satisfy me (not that I'm entitled to be satisfied). I appreciate your answers, really.

Regarding my energy... it's is well spent as I have a better understanding of this now

 

[paranoid]

Thank you cliff(and all at Fractal) for allowing us to test(try out ) this Beta so we can give it a try. looks like some of us are for it and well thank you. It seems like (in theory) it should get us closer to the real deal(guitar, amp, cab, mic, pre, recorded) sound. cant wait to get time to give it a go.

 

[yek]

In to what load? What db?

Can you give me specifics of this statement? What scenario are you seeing this? How many dB? What is the loads impedance?

If you tell me the load you are driving in to I'd be happy to give you the actual test results.
All transformers will have a roll off depending on the load directly related to the cost and size of the transformer.
In most practical situations it is moot.
Thanks
John

Great to see you here around here, Mr Suhr.
It's always great to see the giants of the music industry strive continuously to support their products and answer questions and solve possible issues.

 

[Rex]

SHOWCASE B: Capturing a cabinet with a certain Power Amp by monitoring through an Axe-Fx Amp-Sim

...So, if we NOW subtract via reference IR non-linearities resulting from the actual used Power Amp we subtract something from our subjective "PERFECT" IR (we monitored when finding the sweet spot) to get a more objective "ACCURACY" IR (because we want get rid of the Power Amps influence the Axe should model by itself standalone).

I think mic placement will have a much larger influence on sound than the amp will have. In other words, I think the physical location of the compensated sweet spot will be very close to, if not identical to, its location without compensation.

On the other hand, I agree with you that it would be useful to capture not only a cab's impulse response, but also its impedance curve. This expanded behavior model would advance the state of the art of amp/speaker simulation.