GreatGreen
Power User
Considering Cliff's article about the differences between tube types, specifically about how each type of tube doesn't really do anything to the sound other than change a poweramp's damping factor (EL34's have higher damping than 6L6's, which is why 6L6 tubes can sound more mid-scooped than EL34's, etc), does this mean that tube type doesn't matter when connected to a reactive load?
If a Reactive Load presents a static, pre-defined impedance curve to a tube amp, then it isn't really "reactive" is it. If the impedance curve is entirely predefined, then there is nothing for the tube to "react" with and so it shouldn't matter what kind of tube the reactive load sees. Whatever type of power tube it is, it can't impart any impedance or "damping factor" of its own to that load which means any tube poweramp of a given wattage should sound the same through it, right? If this is the case, then a "reactive load" could be more accurately described as "a resistive load shaped in a way that mimics a real speaker's impedance curve," right?
I'm asking this because I have recently compared an EVH 5150 III 100w Stealth (which uses 6L6 tubes) and EVH 5150 III 100w EL34 amp in my studio by reamping a single guitar line through each amp into a Suhr Reactive Load and IR's. Just by eyeballing the controls to match as close as I could, the amps sounded almost exactly the same.
To put this in more objective terms, reversing the phase on one of the amp tracks and playing both tracks together resulted in a mix about 16 db quieter than each track solo'd. That's very close. Close enough that it takes real concentration to tell the differences and it would most certainly be impossible to tell in a mix. To me, this suggests that either the amps are truly identical in every way or (more likely) that the differences in the impedance curves of the tube power sections (6L6 vs EL34) are being negated by the Reactive Load.
By the way, this is in no way a complaint against the Suhr Reactive Load. I think it sounds phenomenal and certainly better than any mic'd cab solution I've ever come up with for sure, and it has pretty much single-handedly made tube amps viable for me to use at all where I live.
Bonus info: This test has shown me that the EVH 5150 III 100w Stealth and 100w EL34 amps have identical preamps. Don't let anybody tell you that one is "fatter" and the other is "more agile" or that one amp has more gain than the other. I have tested them and can confidently tell you it's just not true. The preamps of the 100w Stealth and 100w EL34 are identical... and through a given reactive load, both amps are basically identical as well.
The 50w amps are a different story, btw. Each of the three 50w models (6L6, EL34, and Stealth) actually do feature different preamp sections.
If a Reactive Load presents a static, pre-defined impedance curve to a tube amp, then it isn't really "reactive" is it. If the impedance curve is entirely predefined, then there is nothing for the tube to "react" with and so it shouldn't matter what kind of tube the reactive load sees. Whatever type of power tube it is, it can't impart any impedance or "damping factor" of its own to that load which means any tube poweramp of a given wattage should sound the same through it, right? If this is the case, then a "reactive load" could be more accurately described as "a resistive load shaped in a way that mimics a real speaker's impedance curve," right?
I'm asking this because I have recently compared an EVH 5150 III 100w Stealth (which uses 6L6 tubes) and EVH 5150 III 100w EL34 amp in my studio by reamping a single guitar line through each amp into a Suhr Reactive Load and IR's. Just by eyeballing the controls to match as close as I could, the amps sounded almost exactly the same.
To put this in more objective terms, reversing the phase on one of the amp tracks and playing both tracks together resulted in a mix about 16 db quieter than each track solo'd. That's very close. Close enough that it takes real concentration to tell the differences and it would most certainly be impossible to tell in a mix. To me, this suggests that either the amps are truly identical in every way or (more likely) that the differences in the impedance curves of the tube power sections (6L6 vs EL34) are being negated by the Reactive Load.
By the way, this is in no way a complaint against the Suhr Reactive Load. I think it sounds phenomenal and certainly better than any mic'd cab solution I've ever come up with for sure, and it has pretty much single-handedly made tube amps viable for me to use at all where I live.
Bonus info: This test has shown me that the EVH 5150 III 100w Stealth and 100w EL34 amps have identical preamps. Don't let anybody tell you that one is "fatter" and the other is "more agile" or that one amp has more gain than the other. I have tested them and can confidently tell you it's just not true. The preamps of the 100w Stealth and 100w EL34 are identical... and through a given reactive load, both amps are basically identical as well.
The 50w amps are a different story, btw. Each of the three 50w models (6L6, EL34, and Stealth) actually do feature different preamp sections.
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