My Live tone FRFR vs Cabs

Amp/Cab in the room is a guitar cab in a room. A FRFR with IRs is not Amp/Cab in the room.

So literally, that's all there is to it? Damn.
I'm gonna go on anyway. ;)

It would be helpful if you gave your definition of AITR.

I take it figuratively to mean the sound, response, and feel of playing an amp in a room, regardless the size of the room, or how far/close I am to the speakers. I don't think that a guitar cabinet is the only source to get the same sound, response, and feel.


You’ll have to excuse me for using non-scientific terminology, but from what I understand, an impulse response of a cabinet represents the frequency spectrum at a very specific point in space. if we, hypothetically, assume that a guitar cabinet is in a room with no walls, thereby eliminating the perceived reflections of sound, the fact that I usually sit about 6 feet away from the cabinet would have an effect.

First, it's not spectrum but Frequency Response at a singular point. The response charted as X frequency and Y amplitude.
Back to my definition. If you have an 8" champ in a bedroom or a Marshall half-stack on stage in a hall, they are both providing an amp in the room experience, right?
 
First, it's not spectrum but Frequency Response at a singular point. The response charted as X frequency and Y amplitude.
Back to my definition. If you have an 8" champ in a bedroom or a Marshall half-stack on stage in a hall, they are both providing an amp in the room experience, right?

Yeah I’m sorry I’m not following your point. Either one of those placed in either of those 2 rooms will give the response of an amp in the room. It will be shitty, but it’s true.

I have not heard your reply on the other parts of my comment. In addition, do you think a closed back FRFR cab can represent an open back amp in the room sound?

Look subjectively you may like the tone. I do. But that’s not the question here.
 
Either one of those placed in either of those 2 rooms will give the response of an amp in the room. It will be shitty, but it’s true.

So sound quality is not a part of it? If that's the case why can't a monitor with the proper EQ curve applied do the job?

I have not heard your reply on the other parts of my comment.

I guess your point (or question) wasn't clear.

In addition, do you think a closed back FRFR cab can represent an open back amp in the room sound?

No. My comments so far are assuming apples to apples in regard to the cabinet enclosure style.

Look subjectively you may like the tone. But that’s not the question here.

Which tone? And can you clarify the question?
I answered in regard to my definition of AITR.
 
So sound quality is not a part of it? If that's the case why can't a monitor with the proper EQ curve applied do the job?



I guess your point (or question) wasn't clear.



No. My comments so far are assuming apples to apples in regard to the cabinet enclosure style.



Which tone? And can you clarify the question?
I answered in regard to my definition of AITR.


1. It’s quality sound to a person sitting next to the 8 inch champ in the hall. It’s shitty for somebody much farther away.

2. You think an open back FRFR can sound the same as an open back cabinet?

3. I was referring to the FRFR tone. You amuly like it and subjectively think it’s same as the amp in the room sound. It’s close - I don’t deny it. But it is not amp in the room.
 
If that's the case why can't a monitor with the proper EQ curve applied do the job?
because EQ doesn't change the way the sound comes out of the speaker. it changes the EQ only.

a guitar cab produces sound in a different way that EQ cannot recreate. it's how the sound is coming out. more "3D" and spread out, compared to a more focused pattern of full-range, especially considering bi-amped woofer/tweeter.
 
1. It’s quality sound to a person sitting next to the 8 inch champ in the hall. It’s shitty for somebody much farther away.

2. You think an open back FRFR can sound the same as an open back cabinet?

3. I was referring to the FRFR tone. You amuly like it and subjectively think it’s same as the amp in the room sound. It’s close - I don’t deny it. But it is not amp in the room.

1. You think so? A small 8" combo sounds like crap in a hall regardless of where you sit/stand.

2. Strawman.

3. So modelers from the beginning back in 1998 were not trying to emulate the sound of amps,
but were trying to emulate the sound of an amp recorded and then played back through monitors?
That's always been the intent?

EQ doesn't change the way the sound comes out of the speaker.

Huh?

1.) a guitar cab produces sound in a different way that EQ cannot recreate. 2.) it's how the sound is coming out. more "3D" and spread out, compared to a more focused pattern of full-range, 3.) especially considering bi-amped woofer/tweeter.

1. Again, huh?
2. How does the transducer and cabinet design work in each case that's so unique? (crossover and tweeter excluded)
3. When did bi-amplification come into it? Do any of the commercially available FRFRs have connections for bi-amping??
 
1. You think so? A small 8" combo sounds like crap in a hall regardless of where you sit/stand.

2. Strawman.

3. So modelers from the beginning back in 1998 were not trying to emulate the sound of amps,
but were trying to emulate the sound of an amp recorded and then played back through monitors?
That's always been the intent?



Huh?



1. Again, huh?
2. How does the transducer and cabinet design work in each case that's so unique? (crossover and tweeter excluded)
3. When did bi-amplification come into it? Do any of the commercially available FRFRs have connections for bi-amping??

An 8 inch champ in a hall will not sound as good as one in the room. An 8 inch champ in the hall will sound significantly different to a person standing next to the amp, to the side of the amp and 50 feet away. An FRFR will sound the same everywhere with a difference if volume.

I’m not sure why you are taking it as a straw man. I believe your point was not to compare an open back cabinet to a closed back FRFR. That’s why I asked the question - if you meant something else hopefully you can clarify?

I am still not following why we are talking about technology or it’s intent 30 years ago? Could you just put your point?
 
3. So modelers from the beginning back in 1998 were not trying to emulate the sound of amps,
but were trying to emulate the sound of an amp recorded and then played back through monitors?
That's always been the intent?
yes.

Original POD marketing:

Whether you use your POD as a direct recording miracle, a stomp box on steroids, for practice, or as a creative digital signal processing tool... we think you’ll agree that POD is about the most amazing thing to happen to electric guitar since ... the guitar amplifier itself.

they clearly reference direct recording first. the owner's manual continues by describing the A.I.R. process which takes into account the cab, mic, and room the amp would live in, to capture all of that for recording purposes.

Pod 2.0 further states on the box:

The ultimate guitar direct recording tool … can also be used as a tone-shaping front end for any guitar amp or live PA or with headphones.

again referencing Direct Recording as its primary function, but also a tone-shaping tool as well. they never claimed it was going to be an amp replacement in their marketing. mostly because they sold amps/combos as well.


EQ doesn't change how a speaker works. guitar speakers and cabs physically produce sound differently than a full range speaker.

most full range speakers have a woofer and a tweeter. i may have used "bi-amp" incorrectly. many full range speakers do have bi-amp capabilities though. of course self-powered speakers wouldn't. i was just trying to comment how a woofer+tweeter is designed to send sound in a certain pattern or dispersion like 90 degrees (mostly the tweeter i guess).

i'm done here. you can research what i've said via many other posts on this topic on this forum or elsewhere.
 
Best I can tell, and after reading all about the CLR (fancy acronym for co-axial btw), the foam
is used to prevent rattles and/or minimize high frequency deflections off of the baffle.

The foam provides what is known as "aperture shading". It reduces the aperture which increases the beam angle (less directivity). The high frequencies don't beam as much.

The beam angle of a piston is lambda/d where lambda is the wavelength and d is the diameter. Shorter wavelengths have a narrower beam angle. Reducing the aperture, d, increases the beam angle.
 
I'm out too. Didn't mean to ruffle any feathers.
We don't agree on an acronym.
Not the end of the world.
 
I did the same experiment the OP several times over the years to get my CLR to sound like my 4x12, and did an A/B test a couple of months ago to compare/dial in an IR I'm generating and refresh my reference for how a cab sounds like.

I've always went with the premise that if the 4x12 and CLR transducers are producing a similar sound/frequency content they will excite the room the same, more or less, getting the elusive "amp-in-the-room" tone, and, most importantly for me, a proper feel. There will be differences to be sure, but the overall effect is quite similar.

Here is the link I posted about this in 2016:

https://forum.fractalaudio.com/threads/amp-in-the-room-here-is-how-i-did-it.116534/

I never slaved for hours trying to get a perfect match; just the overall tonal coloring and feel.

Ultimately, I've always come to the conclusion that I could generate/mix an IR that sounded better then the 4x12 and went with that. And, volume and direct coupling acoustically with your guitar is a big factor here.

Also, over the years when using a tube amp/conventional rig a few times I've preferred the miked up sound coming back thru the monitors vs the cabinet; the tone was richer and fatter, particularly in the mids and had a better controlled low end. Always made me think....
 
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I also very much enjoy the sound of high end FRFR wedges or cabs.

Oh yea....a good, high end FRFR is magic. I started out with conventional monitors (RCF-410, tried some QSC K series versions, EV's, a bunch of others) and was astounded when I heard my AFX thru a Tannoy V12/CLR for the first time.

The Tannoy V12 (coax) was a huge step up but I wanted a powered monitor; the CLR's showed up not long after that.

They Tannoy sounded quite similar to the CLR, I'd have no issue using it for the AX8, etc. Still have it; use it for a rehearsal vocal/instrument side fill. Fantastic speaker...as are the CLR's in that type of deployment.
 
The plastic molded horn used for the tweeter is a wave guide, as noted by the horn pattern. The foam serves no purpose to the LF sound. The wooden baffle in this case is a boundary surface. Cutting a square over a round woofer, and obscuring a lot of surface space in the process, doesn't make much sense, other than to load the low end somewhat - not sure why you'd do it if you're going to be reproducing guitar sounds though.
FYI, it’s not just foam. There’s a horn behind the foam, which allows for directivity control down to 700 Hz from a 12” woofer. Should be evident if you take a look at the photo one more time now.
 
FYI, it’s not just foam. There’s a horn behind the foam, which allows for directivity control down to 700 Hz from a 12” woofer. Should be evident if you take a look at the photo one more time now.

I can see it now. Thanks. Regardless of what the marketing says, that baffle is much too small to provide any significant shaping or directivity of lower frequencies.
A 700 Hz waveform is 1.6 feet long! It would certainly have some affect on any higher frequencies rolling back off the edges of the tweeter horn.

Loudspeaker Directivity

We have discussed directivity elsewhere in general terms. In a loudspeaker system, the directivity is an indication of how directional the loudspeaker is, or to look at it another way, how effective the speaker is at taking the sound it produces and sending it in one particular direction instead of all directions. A loudspeaker that is a high directivity device is commonly called a "long throw" device. A speaker with low directivity is a "short throw" device. This sounds pretty straightforward, but as always there's a catch when dealing with the laws of physics. Because the wavelengths of sound have such a wide range of physical size; from 1/2inch (1cm) to 55 feet (18m), it is not possible for a loudspeaker to have the same directivity (or "throw") at all frequencies.

Bass frequencies have very long wavelengths which make it difficult to control the direction they travel. For a loudspeaker to have moderate control of directivity at 40Hz would require a physical size greater than 18 feet (6m) square. To maintain any directional control at 100Hz requires a size in excess of 6 feet (2m) square. Even at 500Hz, a loudspeaker has to be over 3 feet (1m) square. Up in the rarified atmosphere of higher frequencies, say 2,000Hz+, the speaker can be as small as 1 foot (30cm) square. At ultra-high frequencies, above 8,000Hz, a super tweeter is difficult to build without it having too much directional control, because at any physical size you can build the device it tends to become very directional through its operating band.
 
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I can see it now. Thanks. Regardless of what the marketing says, that baffle is much too small to provide any significant shaping or directivity of lower frequencies.
A 700 Hz waveform is 1.6 feet long!
Plug in the CLR horn’s mouth dimension of 17 inches to the equation shown in the following webpage, and you’ll get 90 degree coverage at 650 Hz. It’s also evident in the CLR manual’s off-axis response graph.
https://www.prosoundtraining.com/2010/05/24/understanding-horn-directivity-control/
It would certainly have some affect on any higher frequencies rolling back off the edges of the tweeter horn.
I’d think so too. I dunno why more speaker designs don’t make use of foam.
 
Plug in the CLR horn’s mouth dimension of 17 inches to the equation shown in the following webpage, and you’ll get 90 degree coverage at 650 Hz. It’s also evident in the CLR manual’s off-axis response graph.

The physics of waveforms is pretty concrete. A 17" square baffle will have very little affect at 650-700Hz.

This is a handy design chart.
https://www.jdbsound.com/art/frequency wave length chart 2013.pdf

I’d think so too. I dunno why more speaker designs don’t make use of foam.

Fiberglass would be even better but it's only used in sealed cabinets - for obvious reasons! :laughing:
 
The physics of waveforms is pretty concrete. A 17" square baffle will have very little affect at 650-700Hz.
Well good thing it’s not a square baffle but a horn. That’s why I referenced the horn coverage equation established by Don Keele...
 
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