Closed Speaker Resonance PA equalization tied to Master Volume level

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None of my amps behave that way. And I have nearly 100.

of those nearly 100 how many don't use negative feedback in the power section? most all of them use negative feedback in the power section so the speaker impedance curve doesn't have much effect on output EQ, their speaker impedance curve doesn't make their power amp resonate. Rectos get an additional layer of output EQ from the speaker impedance curve making the power amp resonate along the speaker impedance curve, since recto modern modes don't use negative feedback. Those speaker impedance curve resonant frequencies get more prominent with higher levels of MV (they make the power amp resonate more along that scoop), so the output EQ changes along a gradient, connected to MV level. It's recto modern mode specific, there should be an output EQ differential depending on how hard the MV is getting pushed. MV barely cracked, just speaker filtering and preamp...MV comes up, lows and highs start to get boosted from PA resonance...that's an additional layer of equalization. It's not missing, it's already modeled and it sounds amazing, it's just not connected to MV. fletcher munson fletcher munson fletcher munson. I bet it's measurable. Fletcher munson isn't measurable. Speaker impedance curve is A D D I N G R E S O N A N C E S to the output EQ. I don't see how that would not be changing the output EQ, adding scoop with increasing strength tied to MV level.
 
Fletcher Munson is entirely measurable and that is exactly why it’s named after those two guys.

I did equal loudness contour experiments myself in grad school, it’s easy to do it and chart your results.
 
Fletcher Munson is entirely measurable and that is exactly why it’s named after those two guys.

I did equal loudness contour experiments myself in grad school, it’s easy to do it and chart your results.

wait wait so when you take measurements of the same signal at differing SPLs, the extra lows and highs actually show up on a graph?
 
Fletcher munson is perceived differential.

From that website https://ehomerecordingstudio.com/fletcher-munson-curve/

Fletcher Munson.png

the speaker impedance curve causing the power amp to resonante along that speaker impedance curve adds an additional layer of output EQ that's dependant on how hard the MV is being pushed. Coincidentally it's the same curve as fletcher munson, but it's actually an additional layer of EQ added at the power amp output from resonance. The speaker resonance is already modeled and sounds great, it's just there isn't any connection to MV level right now. With MV on 0.01 it's the same resonance effect amount as with MV on 3.00. With MV on 0.01 it should sound like it does if you turn the Speaker LF Resonance down to about 1.28 or so, the recto balls haven't kicked in yet. As the MV comes up the balls kick in, it scoops, everyone puts on jumpsuits and starts moshing. Tied to MV level.
 
wait wait so when you take measurements of the same signal at differing SPLs, the extra lows and highs actually show up on a graph?
Not when you take measurements of a signal — because those changes don't happen and therefore can't be measured. But those differences do show up when you measure the human ear's frequency-dependent sensitivity at different volumes. Measurement is how they came up with the Fletcher-Munson curves in the first place.
 
Those speaker impedance curve resonant frequencies get more prominent with higher levels of MV (they make the power amp resonate more along that scoop), so the output EQ changes along a gradient, connected to MV level.
No, no, no. Wrong, wrong, wrong. You keep insisting this is the case but it is not. You simply don't know what you are talking about.

The tone match I showed you is the modern mode of a dual rectifier w/ no negative feedback and the MV at 8 o'clock (barely on).

A tube power amp w/ no negative feedback is a current source. The voltage at the speaker is Iout * Z where Z is the speaker impedance. Iout is proportional to MV, Z is NOT therefore the frequency response (and therefore the sound) is NOT a function of MV.

This is basic electrical engineering stuff. You are simply talking out your ass at this point and making a fool of yourself. I've tried to be nice but you stubbornly refuse to listen to anyone.
 
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wait wait so when you take measurements of the same signal at differing SPLs, the extra lows and highs actually show up on a graph?

Yes, you take a normal hearing (or impaired) listener and present at different intensity levels and frequency and ask them to indicate when they feel the loudness perception is equal.

You record those values and repeat a bunch of times with more listeners and you get a pretty good idea of how loudness perception varies with frequency.

the original FM papers were published back in the 1930’s, it’s a pretty well known and established concept. Sadly, internet guitar forum players seem to have all just learned about it recently so everything is always about FM these days lol. It’s kind of like they moved on from true bypass....

That said, it’s really and verifiable, and you can even perform the measurements yourself with minimal requirements.
 
I'm honestly not here to fling poo, it's been discussed and disclosed before in here that at certain times the edge values of certain pot tapers were not modeled, since those gradient edge settings would not normally be used in any usual real world circumstance, unless some clown started to try and make a 3 foot long modulating comb filter out of a reverb block. It's just with the dual rectifier being so effected by speaker impedance curve and power amp resonance, it would make sense to me that there would be an exponential increase in the resonance / scoop / bloom as MV comes up, since the two resonant peaks get boosted and the middle doesn't, lows fall apart before everything else, and turning down speaker LF resonance reminded me so much of how it felt/sounded at low MV levels. Probably just a finite analog MV pot treble bleed characteristic then. gg guys.
 
I still don’t get the point of the thread..... your essentially arguing that the modeling isn’t correct, or shall we say accurate enough, for a knob setting that no one would likely use. Ignoring the fact Cliff et al., have suggested your wrong, why would anyone realistically want to have the MV set at near minimum on a modeler of all things in the first place ?
Isn’t one big reason to have a modeler that we can set the MV to where it sounds best without having to concern ourselves with it being too loud for a given situation ?

when I play late a night I turn down my output level, but the amp model is still cranked to the sweet spot, it’s why I own a modeler.

why would I want the MV at near minimum for ?
 
the point isn't to get at some difficult to obtain holy grail tone you can only get from low MV, the point of the thread is to connect what i thought to be variable power amp resonances from speaker impedance to MV level, specifically regarding the power amp output EQ curve, so you not only get the distortion characteristic changes at differing MV levels, but also the output EQ differential at differing MV levels.

When you lower the speaker LF resonance parameter as you lower the MV level, it responds feels sounds e x a c t l y like a dual rec, bass goes down to nil and the scoop flattens out, to where below a certain threshold of MV level, there is no more low end resonance being added by the power amp, if you were to turn PA modeling off at that point, there is no further drop off in low end. PA isn't adding any low end at that low of MV. If the only reason it sounds that way in real life is from fletcher munson, then it's just fletcher munson. But since my understanding was that the power amp resonantes more at the speaker impedance resonant frequencies, it would make sense to me that the resonances would increase at those peaks with higher MV, resonance becoming more pronounced with increasing MV, having the same effect on output EQ as turning up one of those Mark V EQ preset knobs with the fixed scoop shape, or increasing the Triaxis dynamic voice parameter, a dynamic scoop shape that increases with prominence along a gradient, applied to the output EQ. But apparently that's not the case. Apparently the power amp distorts more along those peaks with increasing prominence with higher MV settings, but somehow the output EQ is unaffected by the same speaker impedance curve peaks. Must be entirely fletcher munson, combined with the 0.000001 micron edges of a MV pot causing treble bleed in an amp, settings that obviously no one except bedroom superstar would gaf about. The whole point is there is an EQ gradient available, that right now is only manually adjustable with Speaker LF resonance, and coincidentally has the same curve as fletcher munson. Speaker impedance curve does not make PA resonate more with a differing output EQ with increased voltage (current) output, fletcher munson makes it sound like that in real world since you don't have an output level control to keep your face attached, makes sense.

If i could measure stuff I'd measure a sweep at low MV, then measure a sweep at higher MV. The definition of resonance to me is increased FREQUENCY amplitude, I don't see how in the world you would not have increased FREQUENCY output at those speaker impedance peaks with increasing r e s o n a n c e. But apparently the resonance amount doesn't increase with differing MV levels. Then why does the BASS distort first at that peak?? The resonant peak affects the PA distortion with increased MV level, but somehow, the RESONANT peak doesn't affect output EQ, in any capacity, at all, ever, with increased MV. That's where my brain keeps itching.
 
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