Is there a scientific reason to support tube power amps really "feeling" different?

[Sparky Mark]

I own one entry level 300 watt Bugera BVV3000i (SVT clone) all tube head in addition to many lead sled, SMPS class AB and class D amps ranging from 100 to 800 watts output.

I believe I can hear and feel what I'd describe as a third dimensional sound quality to the Bugera that is less present in my other amps. The nearest to it comes from my ancient Trace Elliot heads, which have a certain deep punch (dare I mention "heft"?), but irrespective of volume the tubes still have something extra.

All an amplifier is doing is moving a speaker cone back and forth so what can possibly be different? Do tube output sections produce additional harmonic content that fills gaps left by transistors? Or is it all confirmation bias?

 

[Krakmann]

Salud!

I've never owned a bass tube amp, but every time I've played one, there is a certain... "density" of sound and "natural" compression and a certain behaviour in the upper mids and highs I never feel with a SVT emulation, for example. It's there and it's great.

This said, it's not worth the pain, the price, the size... (FOR ME). I prefer a HX Stomp or a 2 kg class D head everyday. FOR ME.

 

[JRA]

...every time I've played one, there is a certain... "density" of sound and "natural" compression and a certain behaviour in the upper mids and highs I never feel with a SVT emulation, for example. It's there and it's great.

same. edit: i'd add "bounce." my tube preamp gives me a little of that flavor.

This said, it's not worth the pain, the price, the size... (FOR ME).

same.

 

[Scottgun]

I was talking to an audiophile who wasn't a musician, and when I remarked that I was looking into a tube bass amp, he remarked that audiophiles do everything to get all the distortion out of their signal chain while musicians buy tube amps to put it back in. The distortion from tubes are what give the amp its character I would say. Every time I try to add drive to the bass with solid-state gear, I struggle to make it sound less artificial whereas tubes it sounds baked in so to speak. Sorry, I got no science for you.

 

[ProbablyTooLoud]

Curious how you define "feeling."
Are you talking physical or emotional?

 

[Sparky Mark]

Curious how you define "feeling."
Are you talking physical or emotional?

Physical, definitely.

 

[gtirard]

The last time I've used my tube head for a gig, my drummer said he could "feel my sound physically behind his neck".

 

[Passinwind]

IMO, If you want to compare solid state and tube builds scientifically they have to at the very least measure the same for frequency response, THD, IMD, and damping factor. When someone mentions play feel damping factor comes to mind immediately, FWIW.

 

[Zooberwerx]

I own one entry level 300 watt Bugera BVV3000i (SVT clone) all tube head in addition to many lead sled, SMPS class AB and class D amps ranging from 100 to 800 watts output.

I believe I can hear and feel what I'd describe as a third dimensional sound quality to the Bugera that is less present in my other amps. The nearest to it comes from my ancient Trace Elliot heads, which have a certain deep punch (dare I mention "heft"?), but irrespective of volume the tubes still have something extra.

All an amplifier is doing is moving a speaker cone back and forth so what can possibly be different? Do tube output sections produce additional harmonic content that fills gaps left by transistors? Or is it all confirmation bias?

Supposedly so but I can't cohesively explain why. Some noteworthy buzz-terms which will send you down the rabbit hole: damping, sag, pushed to the rails.

Duplicating tube behavior via conventional SS topologies is big business.

Riis

 

[Sparky Mark]

Thanks everyone for your replies. I know this thread will get a lot of anecdotal contributions but I'm hoping for something more fact based, one way or the other.
I'm also hoping for unbiased input (pun intended) from our technical endowed brethren.

 

[Passinwind]

Duplicating tube behavior via conventional SS topologies is big business.

Going the other way is an interesting exercise as well. I built a rack tube preamp several years specifically to see how close I could get it sounding and measuring to one of my solid state ones. Close enough to say "why bother', as it turned out.

 

[Sparky Mark]

Going the other way is an interesting exercise as well. I built a rack tube preamp several years specifically to see how close I could get it sounding and measuring to one of my solid state ones. Close enough to say "why bother', as it turned out.

Funny tale but I'd like to keep this related to tube power amps please.

 

[Michael135]

Not my words: Tube amps are generally perceived to sound "better" due to their characteristic warm, rich, and musical tone, created by even-order harmonic distortion and "soft clipping". Unlike transistors, tubes handle signal peaks smoothly rather than sharply, resulting in a more pleasing, organic sound that is often described as more dynamic and lifelike.

 

[Passinwind]

Funny tale but I'd like to keep this related to tube power amps please.

Copy that. I already gave you my best insight on that aspect, as I've never seen any two amps that will work for a true apples to apples comparison. From a scientific perspective I feel it boils down to "euphonic distortion", and quantifying those mechanisms is both fascinating and frustrating. But also out of my purview, I just build, repair, model, and measure them!

However, I am currently finishing up a tube bass amp build just for the fun of it, and perhaps I'll dive deeper into the scary science of "play feel" as things progress.

 

[Zooberwerx]

Copy that. I already gave you my best insight on that aspect, as I've never seen any two amps that will work for a true apples to apples comparison. From a scientific perspective I feel it boils down to "euphonic distortion", and quantifying those mechanisms is both fascinating and frustrating. But also out of my purview, I just build, repair, model, and measure them!

However, I am currently finishing up a tube bass amp build just for the fun of it, and perhaps I'll dive deeper into the scary science of "play feel" as things progress.

Had to look-up "euphonic"....and "purview".

Riis

 

[agedhorse]

Supposedly so but I can't cohesively explain why. Some noteworthy buzz-terms which will send you down the rabbit hole: damping, sag, pushed to the rails.

Duplicating tube behavior via conventional SS topologies is big business.

Riis

Combining the best of tube and solid state is even bigger business (and also much more difficult to do well).

 

[Aberdumbie]

Having been a bass player back in the "good old days" I can say the biggest difference is in the weight of the beast. If I were toting around tube amps today, I would be a retired bass player. And I'll probably catch flack for this, but the tone options available today with solid state stuff vastly outweighs any perceived difference in the warmth of a tube amp.

 

[baxter_x]

I've played most of the time on hybrid amps but decided to give a try to all tube amps a several years ago.
According to me, tone can be pretty much the same. However it's the presence of tube amps that really makes a difference IMO and IME.
It sounds more massive, wider, heavier.
And I'm always amazed how a 200 watts tube amp is powerful enough for almost any situation. While SS amp should be at least 600 watts.

I had fun comparing my svt2 against my svt7 pro at rehearsals and while the 7 pro is close, there is something about the 2 pro that I enjoy more.
At first I couldn't hear any difference, but the more I use the tube amp, the more I enjoy it.

I guess I'm becoming a tube snob after many years if wondering what's so special about them...

 

[baxter_x]

And I'll probably catch flack for this, but the tone options available today with solid state stuff vastly outweighs any perceived difference in the warmth of a tube amp.

It's probably getting closer but there is still something about all tube a SS can't totally replicate IMO and IME.

 

[baxter_x]

created by even-order harmonic distortion and "soft clipping"

I've read many times that's actually why tube amps a different from SS amps. SS don't produce those even order harmonics which makes them perceived less musical by the brain.