Solid State Amp Watts VS Tube Amp Watts

CVS

CVS

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I have a few amps & I am contemplating buying a PRS amp as my next major purchase. One thing I have noticed is that my solid state 50 watt amp, sounds no louder than my 15 watt tube amp. Have others noticed this, or am I crazy? I have tried to find info on this on the internet but all I have found on the subject is a lot of "technical mumbo jumbo". If any of you can point me to something I can read that is understandable by a non engineer, it would be helpful. Any insight would be appreciated. I used to always think that wattage equated to loudness, but now not so sure.
 
Your ears are correct. Transistor watts do not equal tube watts. Tube watts are much louder. Neither can you think that 50 tube watts will only be half as loud at 100 tube watts. Power is not a linear scale and so 50 tube watts will sound about as loud as 100 tube watts (all other things being equal), but 100 watts will give you other tonal goodies.
 
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AP515 said:
Your ears are correct. Transistor watts do not equal tube watts. Tube watts are much louder. Neither can you think that 50 tube watts will only be half as loud at 100 tube watts. Power is not a linear scale and so 50 tube watts will sound about as loud as 100 tube watts (all other things being equal), but 100 watts will give you other tonal goodies.
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So I wonder if there is a rule of thumb that would tell you that is you have say a 50 watt tube amp, how many solid state watts you need to replicate the loudness (I guess assuming the speakers / cabinets are the same)
 
AP515 said:
...50 tube watts will sound about as loud as 100 tube watts (all other things being equal), but 100 watts will give you other tonal goodies.
Click to expand...
What? No. 50 tube watts can sound about as loud as 100 tube watts, but not necessarily. Either can be louder.

The problem is that watts has nothing to do with how loud an amp can get. There's a measurement that can be taken of an amp called 'gain' (not the same thing as gain on most guitar amps). That will define how loud an amp will be. You can have unity gain, you can have 27db of gain, etc.

I haven't read this link, but this should explain it (warning: contains technical mumbo jumbo):

http://www.audioholics.com/audio-amplifier/amplifier-voltage-gain

Sorry, I can't translate for you, that's not my forté. Also, I have a tendency to use the wrong words at the wrong times, making things worse. I tried to be very careful up there, but don't hold me to it.
 
Wattage doesn't = loudness
Wattage = headroom.
Plus every amp is manufactured differently

You can definitely have a 15watt tube amp that sounds as loud as a 50 watt amp
However it will break up at a lower volume.

Hope this helps, there are other members here who are way more knowledgeable about these things.
 
CVS said:
So I wonder if there is a rule of thumb that would tell you that is you have say a 50 watt tube amp, how many solid state watts you need to replicate the loudness (I guess assuming the speakers / cabinets are the same)
Click to expand...
There probably is wrapped up in all that mumbo jumbo. My small guesstamation would be about 3 to one. A 40 watt tube amp might be as loud as a 120 watt SS amp, but there is a lot if variation involved. Can't really use math to figure it out. It's just a comparison kind of thing.
Dusty Chalk said:
What? No. 50 tube watts can sound about as loud as 100 tube watts, but not necessarily. Either can be louder...
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I agree. I was just trying to generally state what I hear. My Lone Star Mesa has a 50/100 switch and the 100 does get louder, but no 2x louder. Not even close.
 
dkilpatrick said:
Wattage doesn't = loudness
Wattage = headroom.
Plus every amp is manufactured differently

You can definitely have a 15watt tube amp that sounds as loud as a 50 watt amp
However it will break up at a lower volume.

Hope this helps, there are other members here who are way more knowledgeable about these things.
Click to expand...


My impression is that the crux of the issue is pretty much this. An tube amp rated at 50 w will put out a lot more than 50 w when cranked, where the solid state might just put out the 50 w it is rated at.
 
AP515 said:
There probably is wrapped up in all that mumbo jumbo. My small guesstamation would be about 3 to one. A 40 watt tube amp might be as loud as a 120 watt SS amp, but there is a lot if variation involved. Can't really use math to figure it out. It's just a comparison kind of thing..
Click to expand...

I am tempted to say the the 3:1 guesstimate is fairly accurate based on my experiences to date
 
I've gone from tubes to playing with an Fractal Audio Axe Fx II and recently an Ax8. With the Ax8 now I have a Friedman ASM-12 and a Matrix FR10 powered speakers. These are both specifically built for things like the Axe Fx and they are 500W (the Friedman) and 300W (Matrix) respectively. Another popular choice is the Atomic CLR and that's also 500W. I mostly use the Matrix because it's super light and at 300W I can tell you it's not a lot of headroom. The other guitarist in our band is playing a Egnater Rebel 30 (30W) and I'd say the Matrix is about as loud as that.

Based on this I'd say that an accurate estimate would rather be 10:1. Typical band tube amps when playing in bands these days are in the 30-50W range and typical powered speakers are in the 300-500W range.
 
AP515 said:
I agree. I was just trying to generally state what I hear. My Lone Star Mesa has a 50/100 switch and the 100 does get louder, but no 2x louder. Not even close.
Click to expand...

Double the power produces only a 3db increase in volume when maxed.

Tube amps distort and compress more gradually than solid state amps. And they can exceed their rated power (remember power ratings are X amount of Watts at Y% of distortion) and distort in a sometimes-good way, while solid state amps become fuzzboxes when they go past their rated power into distortion.

Whether the speakers present a good or optimal load for the amplifier also matters.
 
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OK - so I take it from everything that I see hear that speakers also play a role in how loud a particular amp can sound. What does one look for in a speaker to determine what level of volume (note - I deliberately did not use the word "wattage") it is capable of handling? Is it speaker ohms? Something else
 
Efficiency, sensitivity, power, wattage, tubes/solid state.... none of it matters. All that matters is the subjective experience of the sound.
 
coyote said:
Efficiency, sensitivity, power, wattage, tubes/solid state.... none of it matters. All that matters is the subjective experience of the sound.
Click to expand...

You're kind of begging the question; of course that stuff matters when choosing what you're going to use, because it affects the subjective experience of the sound.
 
CVS said:
OK - so I take it from everything that I see hear that speakers also play a role in how loud a particular amp can sound. What does one look for in a speaker to determine what level of volume (note - I deliberately did not use the word "wattage") it is capable of handling? Is it speaker ohms? Something else
Click to expand...

Efficiency. It's one of the reasons an AC30 loaded with Alnico Blues can hold it's own against a Marshall into Greenbacks or G12T-75s.

Another reason is frequency response. An amp that's pumping a lot of midrange will be perceived as louder than one that's more scooped. The Mesa Mark III Coliseum and Triple Rectifier (180w and 150w, respectively) weren't about being louder so much as having more headroom to help maintain a more dynamic low end with less compression.

And - as mentioned earlier - tube amps can way exceed their rated power. A 100w Marshall Super Lead is known for being able to peak at 170-180w on transients. A 100w solid state amp is going to clip hard if it goes above 100w. As a result, you wind up turning the 100w solid state amp way down to keep it from breakup up, whereas with the Super Lead you're going to turn it up and it's going to compress. Typically, you need to have about 3x the power to equal a tube amp.

Where it gets even more fuzzy is that not all 100w amps are created equal. From what I've read the 100w Marshall Vintage/Modern for instance only outputs about 80w since they intentionally reduced the headroom so it would sound better at lower volumes.
 
there are always some interesting responses when this topic comes up... :)
 
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