Can you increase girth without increasing wattage?

[Nickerz]

Recently in some A\B testing, the Deizel Herbert (180w) came out on top by only an RCH. But it just had a touch more girth in the same way the Tripple Rec does over the Double Rec. So my Q is, is it possible to overspec the PT to get the punch, or is there a required equal draw (more tubes, higher draw per tube, higher plate voltage) to that spec to get that big iron sound?

[Lauri]

I've seen lots of ads online that promise both girth and length. Don't know if they work but I'm sure through sheer tyranny of will anything is possible.

[pdf64]

I suppose that monster AB amps will still be in their class A area of operation even at regular gig power outputs.
So maybe a 50W class A amp would give the same effect?

[roberto]

Have you ever tried a SS class D power amp?
That could be your preferred choice.

[jabguit]

I've seen lots of ads online that promise both girth and length. Don't know if they work but I'm sure through sheer tyranny of will anything is possible.

[Stevem]

Sure! Play thru two 4-12” cabinets even with a 50 watt amp, it will be a experience you’ll never forget, I guarantee that 100%!

[Leo_Gnardo]

Sure! Play thru two 4-12” cabinets even with a 50 watt amp, it will be a experience you’ll never forget, I guarantee that 100%!

Agreed! Make sure those cabs are wired for the same polarity first... Meanwhile I have yet to encounter a girth-meter. Nickerz, what did "they" use to quantify girth, whatever that is ? ? ? Inquiring minds want to know. Did they also measure swirl? Did they examine the crystal lettuce and publish reproducible results? And who are "they" anyway ? ? ?

[xtian]

Nickerz, what did "they" use to quantify girth, whatever that is ? ? ? Inquiring minds want to know. Did they also measure swirl? Did they examine the crystal lettuce and publish reproducible results? And who are "they" anyway ? ? ?

Damn critical thinkers ruin everything.

[Leo_Gnardo]

Nickerz, what did "they" use to quantify girth, whatever that is ? ? ? Inquiring minds want to know. Did they also measure swirl? Did they examine the crystal lettuce and publish reproducible results? And who are "they" anyway ? ? ?

Damn critical thinkers ruin everything.

How right you are xtian. I saw it on the interwebs, so it must be true!

[Scumback Speakers]

Recently in some A\B testing, the Deizel Herbert (180w) came out on top by only an RCH. But it just had a touch more girth in the same way the Tripple Rec does over the Double Rec. So my Q is, is it possible to overspec the PT to get the punch, or is there a required equal draw (more tubes, higher draw per tube, higher plate voltage) to that spec to get that big iron sound?

I'm pretty sure you would want one of those mods techs do called "Whomp", "Depth", "Headroom", etc. I bought a Metro 100w Marshall kit that wasn't up to snuff, and I had Carl Esparza (fusion bear) take a look at it.

Replaced a couple dodgy items, cleaned up some wiring, etc. It had all those kinds of mods on the back panel. However each of these mods did bump up the volume (as you'd expect) to achieve the desired tone they offered. And since it already had 100w PT iron in it (stock Metro Heyboer 100w Marshall type I believe), the tranny was likely over spec'd to a higher plate voltage earlier Plexi type.

Long story short, you can get there with a few different ways, just have to be willing to try some stuff and experiment.

[Nickerz]

You bring up a good point, the difference is minor enough that doing it the right way is sort of pointless if you get can 99% there without having 80 watts you don't even want or can't use.

[Nickerz]

Agreed! Make sure those cabs are wired for the same polarity first... Meanwhile I have yet to encounter a girth-meter. Nickerz, what did "they" use to quantify girth, whatever that is ? ? ? Inquiring minds want to know. Did they also measure swirl? Did they examine the crystal lettuce and publish reproducible results? And who are "they" anyway ? ? ?

A\B testing. Same thing you do when you go to the optomitrist. Go tell him he's a psuedoscientist hack and how logical and smart you are. This isn't reddit dude, this post is cringe.

[brewdude]

I want to know more about the crystal lettuce

Really, come on… I mean “girth” is a somewhat goofy term. In fact, most guitarist terminology with regard to tone are ambiguous or at least subjective—and would be absolutely useless if talking to a non-guitar player. Plus, it’s my experience the guitar players chase tonal contradictions—bright and warm, smooth and crunchy, dynamics and compression… it’s confusing.

[Bergheim]

Seriously though, how does the TS define girth? Never really heard this term in audio amp terminology before. My guess is girth = punch..? In that case, stiffer filtering and/or less PS sag would help.

[R.G.]

There are two big problems lurking here. The biggest one is probably subjectivism and the most obvious is the lack of a definition of "girth", "big iron sound", or "punch".

Taking the terms first: as several have noted, "girth" doesn't mean anything in particular as regards sound to anyone other than you, Nickerz. I'm not saying that you don't have a perfectly good idea of what that means to you, it's just that it doesn't mean much that most other people can relate to in a way to tell you how to get more or less of it. I get reminded of this concept regularly, as I have quite mild red-green color blindness, and my wife has simply incredibly accurate color vision. I may think a shirt is "red", and it is. She knows exactly which of the 57 shades of red it is, and what "color overtones" of green, blue, etc. that it also carries and can describe them very, very accurately.

Technologists have come up with an answer for this problem: measurement. First you describe in detail what the concept means, pinning it down in some way, then come up with some way to measure it in numbers that are not swayed by the unconscious human mind messing with perception. I may not be able to say that a shirt is "pomegranite red", but I sure can read a spectrum meter and tell you that the principle reflected light intensity is at 650 nM, with smaller peaks at 540 nM. Turning that around, until you can define what "girth", "big iron sound", punch", etc are and measure them, you may not be able to find anyone who can help you. Remember the story of the blink men and the elephant? Every one of them was truthfully describing their own perception of the elephant. Especially on an internet forum, someone telling you how they get girth without watts may be doing their very best to help you, but be describing something else entirely.

Bottom line: for technical help on an issue like you describe, you pretty much need to describe what the term means and how to measure it. I'm just guessing that you're describing something to do with bass frequency response, bass attack time as measured on tone bursts, possibly some subtle effect of soft bass distortion, and maybe even just the visceral feel of a bass note. "Big iron sound" in transformer output amps is nearly always related to bass, as that's what you do in an output transformer to get response to lower bass frequencies - you make the transformer bigger. As one of the responders mentioned, you might do better skipping the output transformer entirely with something like a big solid state amp, maybe a Class D. You can get bass response incredibly wider than any transformer output amp that way.

I can practically feel you either bristling or chuckling at that last comment, because A-B-ing amps is a subjectivist kind of activity. I'm not saying that A-B tests aren't usable guides at all. It's just that what they measure is you, not the amps. And they measure things about you that you may not be aware of, in ways that you may not be able to tease apart into something a technician can help you with, other than by pure luck. As an example, people who measure and study human hearing and musical perception have found that humans reliably think that a sine wave tone with maybe 0.5-1% second harmonic distortion think the sine wave sounds more musical, but cannot distinguish that there is any octave in it at all. Output transformers have built-in distortion as a property of the iron's magnetic hysteresis that is measurable, and is inevitably mixed in with the sound through the transformer, especially at the lowest frequencies the transformer passes.

... er, unless the amplifier circuit uses a lot of feedback to correct the iron's distortion. And at the same time the feedback doesn't make the whole amplifier ring slightly at both of the high end and low end of the amplifier's pass band. And whether the iron makes third harmonic or second and third harmonic distortion depends on whether the iron is used push-pull or single ended - or, an offset single ended sound on the low power end of a push pull stage that's got a bias offset, and how that transitions as volume increases. All of these can play into it. And they may play into it in the same amp.

Another issue with subjectivism is that human hearing perception is not a single-variable thing. There is a tendency in subjectivism to make comparisons along a line, as in "these seventeen amps have been arranged in order of increasing < insert term here >." But that's not the case. Human hearing mixes up and overlays things. As with the soft-distortion thing above, human hearing will quite unconsciously mix up distortion, attack/decay, ringing, and other things into the perceived "sonic picture" that our conscious minds see. There are many variables involved in the "sound" of an amp - frequency response, time response, stability, transient response, even things like speaker feedback into the tubes and/or ceramic caps in a tube amp.

As Lord Kelvin said:
When you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind: it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science, whatever the matter may be.
Popular Lectures and Addresses vol. 1 (1889) ‘Electrical Units of Measurement’, delivered 3 May 1883