Axe-Fx II Firmware Version 12.04 Public Beta

Thank you Cliff, as always; Amazing updates; On high gain I will note I cant hear a thing different between tube classes, Im guessing the subtleties are mainly on clean high MV models?
anyone hear any differences with the different tubes, still not me.
 
and Paco to the rescue again :). thanks for that !
I've got one more for you if you don't mind, as this is a common "mod" done to JTM45s, Plexis and 800s... KT66 into an EL34 amp.

really appreciated !

Okey :)

In the early days of Marshall amplification they often used KT66 tubes together with the Drake 784-103 OT which had a primary impedance of 8kOhms (for a pair of KT66) - JTM45 originally was equipped with this OT, therefore default configuration of a JTM45 must be KT66 instead of EL34

If we compare this to a common Z of 3.2K to 3.5k on an EL34 OT, this would result in 0.43 as your tranformer matching factor.


That brings me to another topic, Cliff might want to chime in. There are some parameter most of us wouldn't touch or even thought about, I remember Cliff saying once he would hide them because the fact nobody touch them (I begged to let them stay in) - Power Amp Bias Excursion, Recovery Time and Excursion Time. Those will change when another amp is selected but they stay if you choose another tube (and regarding to Cliff also the OT and the PI). If the coupling caps and grid leak resistors remain the same, okey - these parameter wouldn't have a change. I would say, this should be a further topic for the Cliff Notes section, but here is a little preview à la Paco :mrgreen

To explain them quickly..... a high overdriven tube goes into grid current which charges up the coupling capacitors now adding extra voltage to the grid - if harder driven, the bias point get lower and the amount of blocking distortion rises. The result is known as "Bias Excursion". Now there were two other parameter "Excursion Time" (how long the excursion concours) and "Recovery Time" (time constant of the coupling cap and the grid leak resistor). Increasing Bias Excursion and recovery time will make your sound weak, fizzier and fart-out on harder attacks (palm mutes riffing and higher MV settings). It also affects the harmonics in your overdriven signal in a special way ....lower settings were used as default on various amp models and lowest on soild state amps sims (there is no such thing - that's why the JC120 has no amount of "bias excursion" at all). You can boost this effect by lowering the bias point (Pwr Amp Bias) which also makes the sound a bit more explosive on harder riffage (especially on classic marshall amps IMO)

The coupling cap capacity does not just define the amount of possible bias excursion on the following driven tube, it also affects the amount of low frequencies. More capacity = lower frequency pass and more possible bias excursion. (As an example - Hifi-tube-amps would have maximum possible bias excursion - but since they were not driven that much, you'll never hear any such things. But if you want to show the ugly face of your tube fanatic hifi-freak - turn up his stereo and make it worse....hahahaha :lol )For an even detailed simulation you can also adjust the "Pwr Amp LowCut" parameter up to personal taste.....

There many more things - but I only can assume how the simulation is working.... ;)

Cheers
Paco
 
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anyone hear any differences with the different tubes, still not me.

Differences were really subtile - I would say it's more of a feel thing on higher MV settings. Therefore you might can hear it, because of your playing when feeling it! But if you mismatch the OT (Transformer Match), then you might get better hear- and feelable differences - as you get if putting KT66 into a EL34 Marshall amp as in the example above.

Try it....have fun!

Cheers
Paco
 
Changed a JTM45 patched (jumped version) to KT66 with transformer match at 0.43, and I like it. Need to spend time tomorrow with the monitors cranked and with the amp model gain dimed.

Okey :)

In the early days of Marshall amplification they often used KT66 tubes together with the Drake 784-103 OT which had a primary impedance of 8kOhms (for a pair of KT66) - JTM45 originally was equipped with this OT, therefore default configuration of a JTM45 must be KT66 instead of EL34

If we compare this to a common Z of 3.2K to 3.5k on an EL34 OT, this would result in 0.43 as your tranformer matching factor.
 
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Okey :)

In the early days of Marshall amplification they often used KT66 tubes together with the Drake 784-103 OT which had a primary impedance of 8kOhms (for a pair of KT66) - JTM45 originally was equipped with this OT, therefore default configuration of a JTM45 must be KT66 instead of EL34

If we compare this to a common Z of 3.2K to 3.5k on an EL34 OT, this would result in 0.43 as your tranformer matching factor.


That brings me to another topic, Cliff might want to chime in. There are some parameter most of us wouldn't touch or even thought about, I remember Cliff saying once he would hide them because the fact nobody touch them (I begged to let them stay in) - Power Amp Bias Excursion, Recovery Time and Excursion Time. Those will change when another amp is selected but they stay if you choose another tube (and regarding to Cliff also the OT and the PI). If the coupling caps and grid leak resistors remain the same, okey - these parameter wouldn't have a change. I would say, this should be a further topic for the Cliff Notes section, but here is a little preview à la Paco :mrgreen

To explain them quickly..... a high overdriven tube goes into grid current which charges up the coupling capacitors now adding extra voltage to the grid - if harder driven, the bias point get lower and the amount of blocking distortion rises. The result is known as "Bias Excursion". Now there were two other parameter "Excursion Time" (how long the excursion concours) and "Recovery Time" (time constant of the coupling cap and the grid leak resistor). Increasing Bias Excursion and recovery time will make your sound weak, fizzier and fart-out on harder attacks (palm mutes riffing and higher MV settings). It also affects the harmonics in your overdriven signal in a special way ....lower settings were used as default on various amp models and lowest on soild state amps sims (there is no such thing - that's why the JC120 has no amount of "bias excursion" at all). You can boost this effect by lowering the bias point (Pwr Amp Bias) which also makes the sound a bit more explosive on harder riffage (especially on classic marshall amps IMO)

The coupling cap capacity does not just define the amount of possible bias excursion on the following driven tube, it also affects the amount of low frequencies. More capacity = lower frequency pass and more possible bias excursion. (As an example - Hifi-tube-amps would have maximum possible bias excursion - but since they were not driven that much, you'll never hear any such things. But if you want to show the ugly face of your tube fanatic hifi-freak - turn up his stereo and make it worse....hahahaha :lol )For an even detailed simulation you can also adjust the "Pwr Amp LowCut" parameter up to personal taste.....

There many more things - but I only can assume how the simulation is working.... ;)

Cheers
Paco
if I could double like I would :). thanks so much for for the calculation and the little inside info. very helpful. eventhough I use quite a few advanced parameters, I have to admit I never changed Bias Excursion. will definitely play around with that now !
 
i don't get it-setting an amp block to default using the "double click" on the BYPASS button - what does that accomplish? how does it rectify the situation of the 12.04 update not being as punchy and tight/focused as 12.03? when you do a firmware update, and restart Axe-Edit, it automatically reads the new block definitions, so is this not already accomplishing whats meant by "resetting the amp blocks"?
 
Use Ideal Tetrode/Pentode as your tube type, also increase damping a bit, maybe switch preamp sag off. I have my 12.03b4 ODS-100 Lead 3 patch back almost 99% under 12.04b...
 
thanks Paco i will try this but what to do when there is over a hundred pre-sets potentially affected? this is very daunting and especially having to do tedious A/B ing, the only way by listening to a pre-recorded example of the previous firmware's preset and this then done essentially w/ all pre's and scenes. i may decide to hang myself first!
 
i don't get it-setting an amp block to default using the "double click" on the BYPASS button - what does that accomplish? how does it rectify the situation of the 12.04 update not being as punchy and tight/focused as 12.03? when you do a firmware update, and restart Axe-Edit, it automatically reads the new block definitions, so is this not already accomplishing whats meant by "resetting the amp blocks"?
Axe-Edit reads in the new block definitions (that lets Axe-Edit know what the new block parameters are all about), but it doesn't set up your presets with the new defaults for those parameters. That's what resetting the amp block does.
 
i think i see what you're saying- the new firmware blocks are read, but the pre's still contain the old block info- so is resetting the amp blocks as simple as double clicking the BYPASS button as J-Beard asserted and is this the only area to do maintenance on? ...and i guess experimenting on a clone of the old preset? (still have the rope nearby):miserable:
 
It's sort of like that, but not quite. When Axe-Edit reads the new block definitions, it's getting information like "this is the new amp block, and here's a list of the parameters that are in the amp block." On the other hand, when you reset the amp block, your preset is getting information like "here's how you adjust all those parameters to make the amp sound authentic." Then you have to SAVE the preset to make those changes stick.
 
so hitting the BYPASS for a reset won't necessarily adapt the new block definitions but will sort of tweak your old preset and it essentially will sound different (hopefully improved) even if you don't want it modified?
 
Sorry guys but there is another post named 12.04 yeah!
Is there any 12.04 or we are still to 12.04b?
Thanks a lot :)
Albion
 
Sorry guys but there is another post named 12.04 yeah!
Is there any 12.04 or we are still to 12.04b?
Thanks a lot :)
Albion


Its kind of confusing, there is a 12.04b out there, but the final release, will be 13.0, once it's released.
 
Sorry guys but there is another post named 12.04 yeah!
Is there any 12.04 or we are still to 12.04b?
Thanks a lot :)
Albion

I fell for that too.

That thread should have read 12.04b Yeah!

He created a stir by neglecting to include the beta after the .04

Firmware 13.0beta is with the beta team, and that will be the next official release. We won't get anything else in the 12 series.
 
I fell for that too.

That thread should have read 12.04b Yeah!

He created a stir by neglecting to include the beta after the .04

Firmware 13.0beta is with the beta team, and that will be the next official release. We won't get anything else in the 12 series.

I shall ask the beta gods for forgiveness for neglecting to include the "b" after "12.04." ;)
 
so hitting the BYPASS for a reset won't necessarily adapt the new block definitions but will sort of tweak your old preset and it essentially will sound different (hopefully improved) even if you don't want it modified?

Double-clicking Bypass resets all the amp parameters to default, including the advanced parameters and the standard parameters such as gain, treble, middle, bass. I prefer to "reset" the amp by temporarily choosing a different amp model and then setting it back to my original model. This resets only the advanced parameters. It leaves gain, treble, middle, bass, etc. as they were.

Terry.
 
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