What do people mean when they say modelers "lack the amp feel"?

[northern_fox]

So like I said... I would like to know how exactly this is all being tested. Because the claims put forth do not go hand-in-hand with the physics behind the phenomenon.

It's not "being tested". It's common knowledge to anyone who has spent a lot of time around amps. Nobody here is debating physics. In my case, a 1000W class AB power amp (matrix) is not much louder than my mesa 400+ (a 300W tube amp), even using the matched impedance for the matrix power rating. I know this because I've used both with the full band many times. Similarly, my JCM800 is as loud or louder than the ICE power amp in my kemper power rack (600W) driving the same cab. The SD170/200 are just barely loud enough to hang with a loud halfstack of half the rated power or less. I have a rocktron velocity power amp with 50W outputs that is put to absolute shame in terms of volume by my 40W fender HRD. All easily compared with matched impedance and cabs. I'm not making this up. Why do you think matrix only sells only 800+ W power amps if the loudest tube heads are just 150W and why FRFR speakers are absurdly over specced in terms of wattage?

I would say you'd actually have to go pretty far out of your way to find an example otherwise. Hence, my original comment, that SS amps generally have 2-3x as much rated power as tube heads to produce the same maximum room volume.

 

[Stratoblaster]

Tube power amps will compress hugely without any apparent distortion before even getting close to hard clipping which gives them a large 'clean headroom' of sorts. Solid state power amps will have headroom until they don't and clip harshly and immediately.

A 50W tube amp will 'sound louder' then a 50W solid state amp, particularly with cleaner tones, as you can turn up the tube amp a lot more before detectable clipping/distortion occurs vs a solid state amp, giving the perception that it's more 'powerful' even though the wattage is the same.

I've run my Marshall 4x12 cabs with a 50W JCM-800 for years and also have driven it with solid state power amps as well with tube/SS preamps.
I even modded the JCM-800 to accept a power amp input and ran preamps into it and into the 4x12.

I needed about a 400W (into 8-ohms) power amp to get the same clean headroom and apparent volume/push as the tube amp, again, particularly for clean-ish sounds. I had to be careful as the cabs were only 275W but I never came close to clipping the SS power amp and could get a pristine, loud, clean tone without the amp going off the rails.

A watt is a watt indeed, but it's a bit of an apples-to-bowling-balls comparison between the two topologies when rating power vs 'perception' in this case.

 

[laxu]

Also worth reminding that knob positions on different amps are not comparable. If your 100W tube amp at 4 is as loud as than a 100W solid-state amp at 9, that just means the tube amp reaches its rated output at about 4. Use a decibel meter if you want proper comparisons because we are not good at evaluating volume accurately by ear.

 

[Stratoblaster]

As to the OP question, in my experience it's because the magic, strange, interactive eco-system that are the power tubes, an output transformer, a speaker motor, negative feedback (if present), and the entire power amp circuitry all interacting with each other in a myriad of complex, dynamic ways, that largely gives a tube amp it's 'feel'. You can lean into a good tube amp with your right hand and it pushes back, yields, and provides a complex visceral interplay. You get a sense of connection with the amp in your left hand that makes fretting easy, expressive, and full of nuance.

IMO, when people say modelers lack feel it's because all of that isn't being replicated/modeled correctly or is simply not even close. That's why when Fractal firmware release notes say things like "improved output transformer interaction" or "more accurate speaker motor modeling" I go nuts heh.

 

[Orvillain]

If you've ever done these comparisons you would realize that the difference you hear is more significant than say 10-20% in wattage.
I have a Ibanez tone blaster head that I've stood in-front of cranked as loud as it could. Every dial on ten and the boost engaged.
It was loud but not ferociously loud.
I dare you do that with a 100 watt Hiwatt.
With the Hiwatt you will flinch it's that loud and feel it in your chest.
Even a 50 watt Hiwatt will have your pants flapping if your in front of it.

How is that at all relevant to the topic?

 

[Orvillain]

It's not "being tested". It's common knowledge to anyone who has spent a lot of time around amps. Nobody here is debating physics.

You are debating physics. You are claiming that a 100-watt valve amp is equivalent to a 300-400watt solid state amp, and I am saying that is not in line with the known and observable physics behind power amplification. Just because something is perceivably comparable does not make it necessarily so.

IE: It isn't the wattage in a valve amp that matters. It's the impedance loading of the output transformer and the soft clipping nature of the circuit, which allows you to push a 100watt amp much much further than a mere 100watt figure implies. At full tilt many valve amps have been measured at almost double their stated output. But in such a scenario, it isn't really a 100watt amp at that point. So even that doesn't serve your concept.

The bottom line is, wattage is not a measure of volume. It is a measure of power transfer, either as a static measurement, or over time. So you cannot use wattage alone to make claims about loudness.

The reason that a 100-watt amp seems loud and a 100-watt solid state amp doesn't seem as loud, is very little to do with the wattage, and everything to do with the design. Solid state power amplifiers do not work the same way, and do not have the same relationship with the speaker.

You should be clearer in your comments, because they are misleading.

I'm not making this up.

Common knowledge != knowledge

A 5-watt valve amp would seem hugely louder than a 200watt solid state power amplifier, in the right conditions.

A 50W tube amp will 'sound louder' then a 50W solid state amp, particularly with cleaner tones, as you can turn up the tube amp a lot more before detectable clipping/distortion occurs vs a solid state amp, giving the perception that it's more 'powerful' even though the wattage is the same.

Wattage is not enough information to make this claim. My point was that simply doubling the rating of the solid state amp will not necessarily get you any louder than the 50-watt solid state amp. And with a tube amp I think it is more the case that the clipping/distortion is easily detectable, but we like it, so we don't mind going further. There are definitely points at power consumption where a valve amp starts to sound just as poor as a solid state amp can. Loadboxes help reveal this; my Diezel VH4 sounds pretty naff when the master volume is cranked. It goes extremely dark and more like a fuzz pedal than a nice cookin' amp.

Point being... in a parallel universe where humans do not like the sound of clipping or harmonic distortion, a cranked "100watt" tube head would not be desirable, so no-one would crank them, so no-one would feel the need to say things like "a 100watt valve amp is equivalent to a 200-300 solid state amp"

Also worth reminding that knob positions on different amps are not comparable. If your 100W tube amp at 4 is as loud as than a 100W solid-state amp at 9, that just means the tube amp reaches its rated output at about 4. Use a decibel meter if you want proper comparisons because we are not good at evaluating volume accurately by ear.

Yes, this is true. Which is why output is measured at wattage stages, rather than knob positions. Although humans are pretty good at evaluating volume accurately. We tend to be able to tell the difference between loudness within a 3dB window. Trained people can usually go a bit lower, at around 1 to 1.5dB window.

 

[northern_fox]

You are debating physics. You are claiming that a 100-watt valve amp is equivalent to a 300-400watt solid state amp, and I am saying that is not in line with the known and observable physics behind power amplification. Just because something is perceivably comparable does not make it necessarily so.

You should be clearer in your comments, because they are misleading.

I've said rated power over and over, which clearly corresponds to what the manufacturer states power output as, not what you are presumably measuring at full tilt on the tap. In reality, a 50W solid state amp is going to be blown away by a 50W tube amp in most cases. Whether that tube amp is "really" at 50W or 80W or more doesn't matter, because it's still sold as a 50W amp and other tube amps are rated similarly. I think you're being deliberately obtuse by claiming physics don't agree with me, when it's obvious you know exactly what I'm referring to with these numbers and that they're in line with specifications put out by manufacturers as opposed to real measurements. Nobody is measuring the power vs volume at the back of their amps when they talk about them.

 

[Orvillain]

Ok dude.

 

[northern_fox]

Ok dude.

Original, deep cut

 

[rrhoads17]

Let me just preface this by saying I have close to ZERO experience with tube amps so I'm just trying to understand/gain some more insight on this.

What do people mean when they say modelers lack that "amp feel"? How does an amp into a loadbox with the same IR compare? Is it just a mental thing knowing you're playing a physical amp vs a modeler? I do know that some people will just flat out detest a modeler because its digital and not analog. Also i do know that modelers are more of a recorded guitar tone vs amp in the room tone, is this where people are getting the two confused maybe?

Thanks!

A lot of the “feel” people talk about, other than a loud cab moving air, is the literal feel underneath your fingers when playing the amp. Tube amps are very sensitive to pick attack, but modern modelers have definitely made great strides in replicating that to where it’s indistinguishable. Also, tube amps can have uncontrollable feedback when really loud which isn’t very common with a modeler since they are played direct most of the time. Because of that, people are used to riding the volume knob while playing tube amps and some people actually like doing that. In my opinion, the general feel of a tube amp can be easily replicated with a Fractal and power amp into a cab. This is what Vivian Campbell does in Def Leppard to achieve a more tube amp experience. “Feel” is also a marketing ploy used by boutique amp builders to sway people away from modeling. They know deep down that new tube amps will be pretty much obsolete within a matter of years, just like the VCR, CD and DVD. That’s why you see a lot of amp makers making solid state versions and plugins of their tube amps. Not to mention, tubes will just become harder and harder to find and buy as the years go on due to regulations, force majeure, or foreign conflict, ie Russian and Chinese tubes.

 

[Mystic38]

It's not "being tested". It's common knowledge to anyone who has spent a lot of time around amps. Nobody here is debating physics. In my case, a 1000W class AB power amp (matrix) is not much louder than my mesa 400+ (a 300W tube amp), even using the matched impedance for the matrix power rating. I know this because I've used both with the full band many times. Similarly, my JCM800 is as loud or louder than the ICE power amp in my kemper power rack (600W) driving the same cab. The SD170/200 are just barely loud enough to hang with a loud halfstack of half the rated power or less. I have a rocktron velocity power amp with 50W outputs that is put to absolute shame in terms of volume by my 40W fender HRD. All easily compared with matched impedance and cabs. I'm not making this up. Why do you think matrix only sells only 800+ W power amps if the loudest tube heads are just 150W and why FRFR speakers are absurdly over specced in terms of wattage?

I would say you'd actually have to go pretty far out of your way to find an example otherwise. Hence, my original comment, that SS amps generally have 2-3x as much rated power as tube heads to produce the same maximum room volume.

I can agree that you may wish to purchase a SS amp of 2-3x power what you may desire in a tube amp, and frankly I would say 5x the power for a class D amp. However, two 100W amps, one tube and one solid state will both produce 100W to the same specification.

The difference is actually not power rating at all, hence my disagreement with your comment, but rather it is how should you rate a guitar amp.

In context, none of these amps are producing 100W in a musical context for any amount of time other than transients. The difference is what happens to the amp once it reaches its limit during transients. Note that during transients the amps are outside their spec as THD will be higher than the spec, but whatever, a tube amp power stage is self limiting and will gradually distort with even order harmonics and compress. The AVERAGE power produced can still increase if pushed further and it certainly will be louder and generally pleasing to hear... perhaps on very fast bpm 1/16th's chuggy chugga chug the average may well be over the 100W rating..but its still a 100W amp.

A solid state amp however will usually clip with odd harmonic distortion, generally unpleasant to hear, and while some better designs have soft clipping/limiting circuitry to stop overloads, the average power during transients cannot increase as much as a tube amp can without (generally) very obvious acoustic complaints, or less so these days, a failure.

the same two amps will be rated the same RMS power into the same load with the same distortion figure.. there is not 2-3x power available... the ability to safely and musically navigate transients without negative artifacts is the difference and is simply a byproduct of a power amp design using tubes.

fwiw, Class D amps have several protection mechanisms and should be held well below anything remotely near max as when they hit the limit, if it doesn't shut down, you may be lucky if it just sounds terrible.. Its a great technology, the best W/$/oz you can get and there are some outstanding modules.. so there is no reason not to use them... but your observations would seem to mirror what i have seen and would expect. fwiw, I use a 900W Genz Streamliner Bass amp for my axe-fx

 

[marsonic]

A lot of the “feel” people talk about, other than a loud cab moving air, is the literal feel underneath your fingers when playing the amp.

Can you describe this?

Honestly.

What would a deaf person feel when playing a tube amp as opposed to something else?

 

[unix-guy]

Can you describe this?

Honestly.

What would a deaf person feel when playing a tube amp as opposed to something else?

I personally don't think they would.

I think feel is a psycho-acoustic thing.

You have to hear the sound and when/how it sounds in order to "feel" it.

To me, a simple example is just straight latency.

You can definitely feel when you're experiencing it because you don't hear the sound when the actions you use to generate it occur, but rather after (technically it's all after, but how much is important).

 

[ernieumass]

What I love about my Axe FX2 compared to a tube head is that I can sit in my apartment, practice at a low volume, tweak it until I get the perfect tone, and at stage volume, I still have the same tone. It gets a tasty tube tone at as low of a volume as you need.

 

[Piing]

What do people mean when they say modelers "lack the amp feel"?

That is said by people that ignores some basic Acoustic Science principles. e.g.: how cabinet with 12" speaker moves the air through a room in comparison with headphones or studio monitors.

 

[unix-guy]

What I love about my Axe FX2 compared to a tube head is that I can sit in my apartment, practice at a low volume, tweak it until I get the perfect tone, and at stage volume, I still have the same tone. It gets a tasty tube tone at as low of a volume as you need.

Not quite... Fletcher Munson pretty much rules that out... You really need to dial things in with the volume turned up or you're going to have too much bass/treble when you turn it up.

 

[Sauro_on_guitar]

I read about it since the first "pod". There's something missing, surely, but today, with such great gear like Axe FX III I think sometimes this fact is related more to something else like hearing guitar tones comes from front (monitor) instead from behind (like with a combo or a stack) and at less volume, so I think putting a monitor behind and raise volume can change this feeling.
But the real question is "why do you think something different from a traditional amp should feel like a traditional amp?". Sometimes I feel lack of meat when I eat my pasta. Is it so strange?

 

[laxu]

I read about it since the first "pod". There's something missing, surely, but today, with such great gear like Axe FX III I think sometimes this fact is related more to something else like hearing guitar tones comes from front (monitor) instead from behind (like with a combo or a stack) and at less volume, so I think putting a monitor behind and raise volume can change this feeling.
But the real question is "why do you think something different from a traditional amp should feel like a traditional amp?". Sometimes I feel lack of meat when I eat my pasta. Is it so strange?

I feel it's more of a "moving the goal posts" thing. It used to be all about "modelers don't sound like tube amps" and now when the answer is "yes they can", the nay-sayers moved the goalpost to a thing that cannot be easily quantified and can be disputed by "but I feel it different."

Even within modeler owners there's a vocal minority who seem to have extremely particular preferences for how something feels. I obviously can't say they are wrong about it, but at the same time question what am I missing when I've had many of the modelers on the market and gotten satisfying results out of all of them through various output devices. Often these feel arguments are also blanket statements like "modeler X is doing this or not doing this" without even considering that there's so many things that change what we perceive as "feel" of an amp.

 

[J.C]

Can you describe this?

Honestly.

What would a deaf person feel when playing a tube amp as opposed to something else?

It's not literal. The feel comes from what you hear and the way that the device responds to your playing.

 

[marsonic]

It's not literal. The feel comes from what you hear and the way that the device responds to your playing.

That was exactly my point.