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Axe-Fx III Firmware Release Version 19.01

unix-guy

Legend!
yeah if it's a Marshall amp and I'm using a huge oversize recto 4x12 IR with Recto large speaker curve I'll put it at .5, to make the 16 ohm default Marshall see what the cab would be, 8 ohms. You can go father than .9 sure, it will just scoop and scoop until there's nothing left.

I think speaker impedance is a scale control, so if it's a mesa 8 ohm amp, 1.0 is 8 ohms and 0.5 is 4 ohms, idk. i think each amp loads reset with its 'normal' impedance, so mesa stuff would be centred at '8 ohms', Marshall stuff would load centred at '16 ohms'. Just to my ears and fingers when you reset Recto 2 it doesn't sound/feel like 8 ohms to me, .9 feels like 8 ohms, speaker impedance knob is pretty sensitive. if i want any more speaker impedance scoop i usually bring speaker LF resonance freq down towards ~80 Hz or whatever spot feels comfy for a given master volume setting, low enough to give it balls and clear up any blurry boomy undesirable mud
There's no need to "guess"... We have a manual ;)

E656A4F0-D18D-46D5-B233-CD419046AB72.jpeg
 

jwa174900

Member
There's no need to "guess"... We have a manual ;)

View attachment 96015
I understand the manual and I thank you for sharing it, I've read it. My curiosity is about what to set the amps impedance to based off of the cabinet. If it is a 4, 8 or 16 ohm load on the amp it will sound different and I'm genuinely curious how the IR's are shot and if it audibly makes a difference when making IR's, I'm guessing it will.
 

FractalAudio

Administrator
Fractal Audio Systems
Moderator
I understand the manual and I thank you for sharing it, I've read it. My curiosity is about what to set the amps impedance to based off of the cabinet. If it is a 4, 8 or 16 ohm load on the amp it will sound different and I'm genuinely curious how the IR's are shot and if it audibly makes a difference when making IR's, I'm guessing it will.
Leave it at 1.0 for accuracy. When you select an impedance curve the actual speaker impedance is part of that data (but hidden from the user). The exposed Speaker Impedance control scales that loaded impedance.

If you are using an MV amp (i.e. 5150) then you really don't need to adjust Speaker Impedance. If you want a more scooped sound lower the MV and vice-versa. Speaker Impedance is a useful control for non-MV amps (i.e. Plexis).
 

jwa174900

Member
Leave it at 1.0 for accuracy. When you select an impedance curve the actual speaker impedance is part of that data (but hidden from the user). The exposed Speaker Impedance control scales that loaded impedance.

If you are using an MV amp (i.e. 5150) then you really don't need to adjust Speaker Impedance. If you want a more scooped sound lower the MV and vice-versa. Speaker Impedance is a useful control for non-MV amps (i.e. Plexis).
Thank you!!
 
I understand the manual and I thank you for sharing it, I've read it. My curiosity is about what to set the amps impedance to based off of the cabinet. If it is a 4, 8 or 16 ohm load on the amp it will sound different and I'm genuinely curious how the IR's are shot and if it audibly makes a difference when making IR's, I'm guessing it will.

Cliff has an example for a non MV amp here:

What to use Speaker Impedance for:
The actual impedance of a speaker can vary quite a bit. For example a Celestion Greenback is available in 8 and 16 ohm versions. The 8-ohm version has a DC resistance (DCR) of 6.57 ohms. The 16-ohm version has a DCR of 12.13 ohms. The Plexi models in the Axe-Fx assume 16-ohm speakers were used as the Marshall cabs used 16-ohm speakers.

The DCR normalized to the speaker impedance is therefore different for the two versions. For the 8-ohm version the DCR normalized to the impedance is 6.57/8 = 0.82. The 16-ohm version is 12.13/16 = 0.76. The relative impedance is therefore 0.82/0.76 = 1.08. Therefore the 8-ohm version of the speaker will increase the voltage at the primary by 8% which means the power amp breaks up a bit earlier (more gain). To simulate this increase Speaker Impedance to 1.08.

The entire post goes into great detail about how the parameter works.
 

Chuck P

Inspired
Leave it at 1.0 for accuracy. When you select an impedance curve the actual speaker impedance is part of that data (but hidden from the user). The exposed Speaker Impedance control scales that loaded impedance.

If you are using an MV amp (i.e. 5150) then you really don't need to adjust Speaker Impedance. If you want a more scooped sound lower the MV and vice-versa. Speaker Impedance is a useful control for non-MV amps (i.e. Plexis).
It is easy to take for granted the luxury that owners of a complex doohickey like an AFX3 have, in receiving clear, authoritative guidance like this. It basically never happens with anything. When I have a question about how exactly the trem works on my CU22, I get a selection of well-intended and pretty useful forum responses, not a complete, concise response from Paul Reed Smith himself. These are truly the good old days.
 

Dave Merrill

Axe-Master
Leave it at 1.0 for accuracy. When you select an impedance curve the actual speaker impedance is part of that data (but hidden from the user). The exposed Speaker Impedance control scales that loaded impedance.

If you are using an MV amp (i.e. 5150) then you really don't need to adjust Speaker Impedance. If you want a more scooped sound lower the MV and vice-versa. Speaker Impedance is a useful control for non-MV amps (i.e. Plexis).
Is the amp impedance behavior influenced by the cab(s) you have connected to it?

I'd guess not, since afaik IRs don't contain any info about the cab's impedance.
 
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DougB415

Experienced
When I have a question about how exactly the trem works on my CU22, I get a selection of well-intended and pretty useful forum responses, not a complete, concise response from Paul Reed Smith himself. These are truly the good old days.
I was just at our shop today and they told me that if I'm not familiar with the trem system, don't mess with it. But just an FYI, Jack Higginbotham does read the PRS Forum. I don't think he does any replies tho.
 

Ugly Bunny

Power User
It is easy to take for granted the luxury that owners of a complex doohickey like an AFX3 have, in receiving clear, authoritative guidance like this. It basically never happens with anything. When I have a question about how exactly the trem works on my CU22, I get a selection of well-intended and pretty useful forum responses, not a complete, concise response from Paul Reed Smith himself. These are truly the good old days.
The information age is fantastic for that; I've casually chatted or interacted with so many of my heroes online. Both FAS and Line 6 are great in their online presence and responsiveness to customer feedback. Granted, the president/owner/perfectionist-in-chief of YGG isn't directly interacting with us, but we have Frank Richotte, Eric Klein, and Igor Stolarski who regularly discuss Helix stuff on forums and social media; that's pretty amazing, plus Cliff and the team here. I would never have dreamed 20 years ago that I'd be able to chat with and give real feedback directly to the person who designed my favorite piece of gear :)
 

DougB415

Experienced
Well ain't that just a Catch-22!
Picked up my messed up CU24 today, plays like a dream now. That PRS 6-screw trem bridge has messed up too many would-be guitar techs. It's supposed to have 1.6 mm spacing (between the bottom of the bridge and the body of the guitar) on all 4 sides for the trem to work correctly. The guy that owned this guitar before me apparently wanted a stoptail. That situation has been rectified, and the trem floats nicely now.

Too bad it can't lose any weight, but it's under 9 lbs so I'll keep it.
 

jcfiallos

Inspired
Good day one question, for update 19.01, is FC-6 already working?, I cant seem to change presets on the FC-6, and I dont know if I should update the FC-6 or if it is not ready yet?, on the FC-6 it says firmware 1.10
 

unix-guy

Legend!
Good day one question, for update 19.01, is FC-6 already working?, I cant seem to change presets on the FC-6, and I dont know if I should update the FC-6 or if it is not ready yet?, on the FC-6 it says firmware 1.10
FC firmware shouldn't matter, but there is newer version.
 

jcfiallos

Inspired
ok one question, I remember before in a past FW there was an option of selecting if you were playing on an amp or direct to console, I dont see it in the new FW's, only power amp modelling on/off, is there something Im missing?, I need to play live tomorrow direct to a console so I was checking here first, thanks in advance for your helpful input
 

rushfan

Experienced
ok one question, I remember before in a past FW there was an option of selecting if you were playing on an amp or direct to console, I dont see it in the new FW's, only power amp modelling on/off, is there something Im missing?, I need to play live tomorrow direct to a console so I was checking here first, thanks in advance for your helpful input
For direct to console, you would definitely want to keep,the power amp on, along with using a Cab IR.
 

willdoughman

New Member
Earlier in the conversation, @CipherHost asked about another USB cable to try.
Cables can deteriorate with use, so I'd certainly swap it for another known good cable, and see if that resolves this issue.
If it were me, I'd probably try exporting a preset from the AF3, testing the USB cable further.
Any chance you've added either a new hardware device or a new application around the time this stopped working?
I can't recall, but if you haven't already deleted AxeEdit, I would do that, and try reloading a fresh version.
We are all hopeful you'll find the key to this frustrating puzzle and get it back to normal.
Cheers,
Lee
Ok, I haven't changed a thing and the problem has gone away when I checked today 🤷‍♂️ What a mystery lol
 

is9582

Power User
Ok, I haven't changed a thing and the problem has gone away when I checked today 🤷‍♂️ What a mystery lol
Indeed! Lol. Awesome to hear it is behaving, at least for now. Intermittent issues are always the most difficult to troubleshoot and resolve, and we never know when they will reappear. Its always a good idea to have a couple of spare cables on hand, just in case.
 
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