Pentode & Triode questions

nikki-k

Experienced
Firmware 3.xx added Pentode *modeling*. I am assuming this is completely behind the scenes, and that for amps that typically utilize a Pentode tube based power section will *simply* be coded as such? Will this ever be cited in the documentation (ie, "JCM800, Pentode, ...")?

If the previous is all true, will we be afforded a setting to choose Triode mode for those amps at some point? While this is an option on some amps that people may use for a "half power" setting (no comment..), I actually appreciate the tonal variance this can afford, which is why I ask. Thanks!
 
I would like to say yes. It seems like a nice feature to add. Let's get Cliff on board.


I'm a high gain djent djent meedley meedely meedely type player...

Sent from my iPod.
 
I have actually found the whole TRIODE/ PENTODE feature to be really vague in the release notes not clearly stating where the feature lies. So I was assuming its parameter was within the TRIODE HARDNESS of the advanced parameter page, (based on what the release notes did say). I would love to have some clarification on this matter... please beta testers... or Cliff.:D
 
I have actually found the whole TRIODE/ PENTODE feature to be really vague in the release notes not clearly stating where the feature lies. So I was assuming its parameter was within the TRIODE HARDNESS of the advanced parameter page, (based on what the release notes did say). I would love to have some clarification on this matter... please beta testers... or Cliff.:D
"Triode" on the Power page refers to the ECC83/12AX7 (et al) tubes. (unless I have suddenly become sane.. I hope not :) ) There is no indicator of Power Tube *assignment* that I am aware of.
 
"Triode" on the Power page refers to the ECC83/12AX7 (et al) tubes. (unless I have suddenly become sane.. I hope not :) ) There is no indicator of Power Tube *assignment* that I am aware of.
I agree, although the v3.04 Owner's Manual still refers to the power tubes as triodes in the description of power tube hardness, so I can see where the confusion might arise.
 
I am also assuming that the "triode hardness" specifically applies to "the next-to-last triode in the chain" as described under the "Triode Plate Frequency" parameter.
 
I agree, although the v3.04 Owner's Manual still refers to the power tubes as triodes in the description of power tube hardness, so I can see where the confusion might arise.
I think this may be a *misprint*. The current manual PDF *definition* for "Power Tube Hardness" is nearly word-for-word what the wiki states for "Triode Hardness." The wiki's "Power Tube Hardness" *definition* states: "This parameter has been added in firmware 3.0. Release notes: "This parameter adjusts how rapidly the power tubes enter saturation. Higher values give a slightly more aggressive distortion character. Lower values give a smoother breakup." The two are entirely similar, save for the use of the word "Triode" in one, and difference in length of definition. After searching the forums, as well as reviewing other materials, I settled on the current wiki *definitions*. Or, I should say, my "votes" are that the wiki is correct; the latest revision of the manual is missing a Triode Hardness entry. (I only have revisions 1.02 and 3.04 of the manual in PDF; neither have an entry for "Triode Hardness")

I am also assuming that the "triode hardness" specifically applies to "the next-to-last triode in the chain" as described under the "Triode Plate Frequency" parameter.
Triode Plate Frequency is now available for two Triodes. Triode Hardness does not have any citation of which Triode; previously, with only the next-to-last Triode available for user adjustment, one could assume that the Triode Hardness parameter may only apply to that Triode. However, I wonder if it now includes the "final Triode" as well, and also if Triode Hardness was ever actually only targeting (what is now?) Triode 1. The (collected) text states that, "This parameter sets the cutoff frequency of the plate impedance for the next-to-last triode in the chain," and then, "The triode 2 plate capacitor is also exposed." While this seems to allude to Triode 1 (Frequency) being the next-to-last since Triode 2 is mentioned later as "..also exposed," it does not specifically state this. I know, I am nit-picking, lol. "Nah, don't worry.. the gun should be empty now." ;)

Since I am a visual + music/math thinker, I actually visualize all of this. Without a more complete, verified set of information, I am kind of stuck with... imagine a blind person, and telling them, "Your hotel room door is up there a ways." Not only do I picture the tube sets in the amps, but I see the tubes "behaving" certain ways.. ways that are not as one would observe while working on an amp, but... it is difficult for me to explain in words, lol. For instance, with Triode/Power Tube Hardness, I currently (pun intended ;) ) picture what would *normally* be nice, warm, glowing tubes; as I decrease Hardness, they begin to.. amber a bit, losing that "white-blue-ishness," and eventually brown, before losing glow and getting.. cold, blobby, and squishy-ish. Going higher, I see them get less amber.. the "reds" thin, the blue begins to whiten more and more, until the glass thins and fractures, and I actually feel pain from the shrillness, and this feeling it will explode. "Your hotel room door is the third one on the right; there is a small braille placard above the key card lock. Enjoy your stay!" :mrgreen

Sorry if I am annoying with these questions.
 
having never had the chance to play with the hardness parm I'd like to know a little more.
Does it alter that amount of maximum distortion you can have?
Or just change the curve of your transition from clean to dirty?
Also, will it alter the voice [tonally] of the distortion?
 
Since I am a visual + music/math thinker, I actually visualize all of this. Without a more complete, verified set of information, I am kind of stuck with... imagine a blind person, and telling them, "Your hotel room door is up there a ways." Not only do I picture the tube sets in the amps, but I see the tubes "behaving" certain ways.. ways that are not as one would observe while working on an amp, but... it is difficult for me to explain in words, lol. For instance, with Triode/Power Tube Hardness, I currently (pun intended ;) ) picture what would *normally* be nice, warm, glowing tubes; as I decrease Hardness, they begin to.. amber a bit, losing that "white-blue-ishness," and eventually brown, before losing glow and getting.. cold, blobby, and squishy-ish. Going higher, I see them get less amber.. the "reds" thin, the blue begins to whiten more and more, until the glass thins and fractures, and I actually feel pain from the shrillness, and this feeling it will explode. "Your hotel room door is the third one on the right; there is a small braille placard above the key card lock. Enjoy your stay!" :mrgreen

Sorry if I am annoying with these questions.
Being a Vibroacoustics analyst, I have to be a bit of a 3D visual and math thinker myself to visualize how sound and structure interact in my job, so I can sympathize. I do wish that the manual was a little more precise for the "advanced parameters." Also, don't be sorry about the questions. They lead to a deeper understanding for all of us.

Further thinking about my earlier assumption. Since the last two triodes in the chain are usually both halves of a 12AX7 dual triode or something similar in an actual amp, could it be that triode hardness applies to both? That would make triode hardness the equivalent of switching out a tube in the actual hardware.
 
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having never had the chance to play with the hardness parm I'd like to know a little more.
Does it alter that amount of maximum distortion you can have?
Or just change the curve of your transition from clean to dirty?
Also, will it alter the voice [tonally] of the distortion?
Not really, No, and sort of...It can soften(warm up) or toughen the parts of the distortion that come from the preamp and power amp individually. It's really a subtle, noticeable change in the tonal character like the difference between forest and emerald green.
 
Further thinking about my earlier assumption. Since the last two triodes in the chain are usually both halves of a 12AX7 dual triode or something similar in an actual amp, could it be that triode hardness applies to both? That would make triode hardness the equivalent of switching out a tube in the actual hardware.
This is part of what I am thinking. Combined with other parameters and some EQ/filtering, it could help emulate cumulative, overall changes (barring unveiling of those deepest parameters... could you imagine being able to plug in numbers? drool...)
 
This is part of what I am thinking. Combined with other parameters and some EQ/filtering, it could help emulate cumulative, overall changes (barring unveiling of those deepest parameters... could you imagine being able to plug in numbers? drool...)
I dream about some day being able to virtually breadboard an amp of my own design from vintage components or one that isn't readily available from schematics and be liberated from the models that are being made by others. Until then, Axe FX II is closest I can come.
 
Mhhh... so I assume the whole question sums up to "where does the pentode instance lies in the software? Does it just applie to those amps that are gifted with actual pentode tubes in real life? Is it something user can change/switch/modulate, or is it just that the pentode amps were previously simulated with a triode model while now they have a pentode simulation all for them?

It seems that most users are left with a doubt...A word of wisdom from those in the know (LOL) would be appreciated!
 
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