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Tube watts vs Solid State watts

Is there a difference in how loud a tube watt is vs a solid state watt?

Or....

Why is it a guitar player can bring a 30 watt single 12 combo up on stage, barely turn up the volume and be loud as heck vs a bass rig?

I guess what I'm asking is what is going on between not only tube vs solid state, but even more so between guitar vs bass heads as far as loudness?

Why does a bass player need a 300 watt head when a guitar player can get by with only a 100 watt head? Does the frequency spectrum the instruments cover have a hand in this?

Psychoacoustics.

A tube amp produces more upper frequency harmonics (especially when overdriven) compared to an SS amp and since human brain perception is to hear higher frequencies as louder you get this scenario.
 
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A watt is a watt. I have close to 30 amps ranging in power from 12.5 watts to 2,500 watts. The volume they produce is pretty consistent with their power rating. However, many of the tube amps do not actually make their full power before they begin to distort. I have one 200W amp that really only makes about 120W clean and another that makes about 165W. Even the iconic SVT with is supposed to make 300W at 3% THD per the factory service manual typically only makes about 265W at 5% THD. My 380W solid state GK amps will easily play clean louder than both of my SVTs pushed into heavy distortion. For this comparison I used the same exact speakers with the SVTs and GK.

Playing guitar through one of my 100W Marshall full stacks cranked will easily bury any of my all tubes amps played with bass...and I have several all tube amps rated for 400W. I suspect playing guitar through my Vox AC30 and pair of Celestion Blues would also bury any of my all tube bass amps. The issue here is bass requires a lot more power than guitar to have the same perceived volume.

I am pretty sure my amps with over 1KW of power and a large efficient speaker can go toe to toe with my Marshalls.

Click the thumbnail...this rig makes 1,800W. Epifani UL902C and four Genz Benz 1288T Uber Quads.

View attachment 3354185

Lol I use to have a similar stack like yours
 

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Rather than try to figure out why, it will save you time and energy to accept the fact that into the same cab, a 100 tube head will seem louder than a 100 watt solid state head. A 300 watt tube head will seem louder than a 300 watt solid state head.

With just a few exceptions, tube heads pretty much stop at the 300 watt range. Peavey had a 400 watter, Reeves still makes a 400 watt one. But they never got popular. Why? Hardly anyone needed a tube head louder than the 300 watt Ampeg SVT. That one has been the standard backline head for decades, has had plenty of power to satisfy most bass players needs.

Now switch over to solid state, and we see tons in the 800 watt, 1200 watt range, etc. That’s what it takes to match the 300 watt SVT head.

The above are generalities, there are obviously people with very different needs who have made very different rigs with very different types of components producing very different results.
 
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A watt is a watt. I have close to 30 amps ranging in power from 12.5 watts to 2,500 watts. The volume they produce is pretty consistent with their power rating. However, many of the tube amps do not actually make their full power before they begin to distort. I have one 200W amp that really only makes about 120W clean and another that makes about 165W. Even the iconic SVT with is supposed to make 300W at 3% THD per the factory service manual typically only makes about 265W at 5% THD. My 380W solid state GK amps will easily play clean louder than both of my SVTs pushed into heavy distortion. For this comparison I used the same exact speakers with the SVTs and GK.

Playing guitar through one of my 100W Marshall full stacks cranked will easily bury any of my all tubes amps played with bass...and I have several all tube amps rated for 400W. I suspect playing guitar through my Vox AC30 and pair of Celestion Blues would also bury any of my all tube bass amps. The issue here is bass requires a lot more power than guitar to have the same perceived volume.

I am pretty sure my amps with over 1KW of power and a large efficient speaker can go toe to toe with my Marshalls.

Click the thumbnail...this rig makes 1,800W. Epifani UL902C and four Genz Benz 1288T Uber Quads.

View attachment 3354185

A watt is a watt yes. And volume should correlate with the numbers provided the numbers are true to the meaning in the first place.

But there is a difference between "volume" and "loudness". Two 100dB signals may both register at the same volume but one might appear louder than the other depending on compression ratio and upper harmonic detail.
 
Don't tube amps generally produce a higher current compared to solid state amps? The tube power vs SS power conundrum has been around as long as tube and SS amps have been in existence (1950's perhaps ?).

Apparently, there is more to amplifier power than just WATTS. CURRENT and RESISTANCE is also part of the equation. And then there is speaker efficiency which is a critical component to creating SPL. All of this has to has to be considered when pairing speakers to a SS or tube amp. A well made tube amp with hefty power transformers can produce high-current which has a lot to do with how a tube amp can produce significant power in relation to it's wattage rating

Tube amps operate internally at lower current and higher voltage. The output transformer is an unfortunate necessity in order to match the output to the speaker by simultaneously reducing the voltage and increasing the current to match 4, 8 or 16 ohm loads.

If a tube amp designer could eliminate the output transformer, that's probably the first part most would get rid of first. The second would be the power transformer and there are some practical examples of where switch mode power supplies have been used in place of a conventional power transformer to save significant weight.

Psychoacoustics.

A tube amp produces more upper frequency harmonics (especially when overdriven) compared to an SS amp and since human brain perception is to hear higher frequencies as louder you get this scenario.
Actually, a solid state amp when overdriven tends to produce more higher ordered harmonics than a tube amp when overdriven.
 
Well there's no such thing as a quick search on this site. Most of the time I wind up with a bunch of threads that are posted in the For Sale section. Or maybe, it's cause the only decent thread I ran across about it is from 2014 and I would like to have a discussion about it with people currently and not a thread that has been inactive over the last 5 years that no one even pays any attention to anymore. Excuse the fk out of me for asking.

But since you decided to pounce I went and used Google and got the answer I was looking for instead of worrying about getting it here or being able to discuss it with someone who is more knowledgeable about it than myself. Have a nice day!
I hope you notice the number of likes you received compared to the bassist that was so critical. Please feel free to ask more questions "that have been asked before". It was interesting enough for me to read the same old material again.

I think that if people never repeated anything that was said before there'd be no one on TB.
 
Tube amps operate internally at lower current and higher voltage. The output transformer is an unfortunate necessity in order to match the output to the speaker by simultaneously reducing the voltage and increasing the current to match 4, 8 or 16 ohm loads.

If a tube amp designer could eliminate the output transformer, that's probably the first part most would get rid of first. The second would be the power transformer and there are some practical examples of where switch mode power supplies have been used in place of a conventional power transformer to save significant weight.


Actually, a solid state amp when overdriven tends to produce more higher ordered harmonics than a tube amp when overdriven.

Isn't it so that the tube amps are supposed to produce 2nd order harmonics while ss amps mostly suppress them? What I am aiming at is that while an ss amp may get in fact louder compared to a tube amp when overdriven but with an unpleasant sound? So people don't even compare it therefore we accept the "fact" that tube amps get louder simply because the distorted signal is actually useful compared to that of an ss. At least that's how I hear it.
 
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Tube amps operate internally at lower current and higher voltage. The output transformer is an unfortunate necessity in order to match the output to the speaker by simultaneously reducing the voltage and increasing the current to match 4, 8 or 16 ohm loads.

If a tube amp designer could eliminate the output transformer, that's probably the first part most would get rid of first. The second would be the power transformer and there are some practical examples of where switch mode power supplies have been used in place of a conventional power transformer to save significant weight.

Actually, a solid state amp when overdriven tends to produce more higher ordered harmonics than a tube amp when overdriven.

Thanks for this, I've always wondered. If you'll indulge me a bit, do speakers tend to have a maximum voltage or maximum current? Is there a normal voltage/current ratio that amp manufactures shoot for? Does the ratio of V:I make any appreciable difference in perceived volume/tone?
 
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Oh yeah, there's that. I spent some time reading up on it last night. I started here...
Fletcher–Munson curves - Wikipedia

Invalid Link Removed

A google search provides way too many links on it to post back here.

And that is the answer to the “guitar watts versus bass watts” part of your original question.

Now all that’s left is the “tube versus solid state” miasma....
 
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I hope you notice the number of likes you received compared to the bassist that was so critical. Please feel free to ask more questions "that have been asked before". It was interesting enough for me to read the same old material again.

I think that if people never repeated anything that was said before there'd be no one on TB.
Oh yeah I noticed. I also noticed that one of the few that "liked" the critical bassist's remark is someone I bought a piece of gear from on here. He just got the last dollar he'll ever get out of me :roflmao:

And I also noticed that the critical bassist hasn't been back either, much less bothered to reply. Just a quick in and out attack and gone. That's okay, there are those who would rather learn, or help others learn that have shown up, and that's the important thing to me. Some people like to be a part of the parade, others like to rain on it and make everyone as miserable as they are. Just a part of life online I guess.

Thanks for your comment and support!
 
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Tube amps operate internally at lower current and higher voltage. The output transformer is an unfortunate necessity in order to match the output to the speaker by simultaneously reducing the voltage and increasing the current to match 4, 8 or 16 ohm loads.

If a tube amp designer could eliminate the output transformer, that's probably the first part most would get rid of first.
That's crazy talk! :)