50W vs 100W Tube Amp Volume Difference

James Freeman

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I was curious how much louder a 100W tube amp is than a 50W.
Both cranked into a 8ohm reactive load, same settings on all external recording gear.

50w vs 100w.png


50w vs 100w graph.png


50W


100W


About 3dB, both are painfully loud into a real cab when cranked.
I also don't hear/see "more headroom" or "more bass", both are about equal in frequency response when cranked.
* I should note that the JCM800 was set like a Plexi, Master Volume at 10 and Gain at about 3.
 
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Bigger amps give more bass debunkt?
I always thought that if the output transformer is properly designed (doesn't saturate at nominal power) it should have flat-ish response.
For what it's worth, the 50w 1987x OT is twice the physical size of my 100w Valveking OT which drops fast below 50Hz when cranked.
 
I was curious how much louder a 100W tube amp is than a 50W.
Both cranked into a 8ohm reactive load, same settings on all external recording gear.

View attachment 18742

View attachment 18743

50W


100W


About 3dB, both are painfully loud into a real cab when cranked.
I also don't hear/see "more headroom" or "more bass", both are about equal in frequency response when cranked.
* I should note that the JCM800 was set like a Plexi, Master Volume at 10 and Gain at about 3.

The 100W imagine looks less compressed than the 50W in your image, and on the frequency graph, the 100W peaks between 100W and 200W have a bigger difference than the ones between 600hz and 800hz.

But yeah, often the differences in tone arent just down to having 50W more, or bigger transformers.
 
The 100W imagine looks less compressed than the 50W in your image, and on the frequency graph, the 100W peaks between 100W and 200W have a bigger difference than the ones between 600hz and 800hz.

But yeah, often the differences in tone arent just down to having 50W more, or bigger transformers.
Same thing happens if you pull two output tubes from a 100w amp.. nothing to do with the transformers.
 
I'd be interested to see the frequency response sweep with a palm-mute loop, rather than a frequency sweep. Also a waterfall graph in Room EQ Wizard would be interesting too, because it would tell you how quickly certain frequencies ranges dissipate over time.

My suspicion is that a frequency sweep, even with white or pink noise, isn't giving you the whole story.

50watt isn't particularly quiet, and 3dB difference is the figure that I've seen thrown around for years and years. But I don't think wattage alone can describe the tonal differences.

If you have an amp like the Orange Rockerverb MKIII 100-watt, that amp can give variable wattage output levels too:
100 WATTS: 4 VALVES (FULL POWER)
70 WATTS: 4 VALVES (HALF POWER)
50 WATTS: 2 VALVES (FULL POWER)
30 WATTS: 2 VALVES (HALF POWER)

So doing tests with all of these modes could be quite interesting to look at.
 
3 dB is about what I got when I compared the 45W Bogner Goldfinger 45 SL and 100W (actually a lot more but it is rated like a tube amp) BluGuitar Amp 1 Mercury Edition. I cranked the OD channel on both using similar tones into a 1x12 Eminence Maverick.

The BluGuitar reached about 120 dB @ 1m. Bogner was 117 dB. Both were painfully loud and rattling everything in the room. Both sound better at way more reasonable volumes.
 
Always heard that a 50W is like 75% as loud as a 100W

I’d guess this is close, I know most 50w amps I would try in my loud ass thrash bands of the past just weren’t quite enough and I needed just that little extra of the 100
 
But it's my only amp! ¯\_(ツ)_/¯

Speaking of amps, the selection in Japan guitar stores is insane, and the pricing sometimes too. I saw a used Laney VH100R for something like $250 today. Right next to a new Two Rock Landreth signature that cost $10K...
Yeah those VH100R's are quite cheap. They're really sleeper amps yknow. Fantastic things. A bit noisy. But really good.

I do remember the Diezel's being very highly priced over there. I played a Herbert over there once, and I thought it was good. But I think they wanted something like £5000-ish for it!
 
I was curious how much louder a 100W tube amp is than a 50W.
Both cranked into a 8ohm reactive load, same settings on all external recording gear.


About 3dB, both are painfully loud into a real cab when cranked.
I also don't hear/see "more headroom" or "more bass", both are about equal in frequency response when cranked.
* I should note that the JCM800 was set like a Plexi, Master Volume at 10 and Gain at about 3.

My suspicion is that a frequency sweep, even with white or pink noise, isn't giving you the whole story.

I agree.

While not 50 watt amps, I've spent a lot of time playing 40 watt amps and 100 watters and have a few 100 watt heads. I also had one extended studio session with a 50 watt Marshall half stack played at concert volume and can compare it to my NMV JCM800 Model 1959.

In my experience the difference between the 40-50 watt amps and the 100 watters isn't volume, it's tone, even with both at the same volume. At the same volume the big iron sounds fuller. I don't know how that would translate to things measured in the graphs posted by the OP but to me it's been a noticeable difference. It's noticeable with the cleans as well as the gain tones.
 
In my experience the difference between the 40-50 watt amps and the 100 watters isn't volume, it's tone, even with both at the same volume. At the same volume the big iron sounds fuller. I don't know how that would translate to things measured in the graphs posted by the OP but to me it's been a noticeable difference. It's noticeable with the cleans as well as the gain tones.
Yeah that is exactly my experience too.
 
Always heard that a 50W is like 75% as loud as a 100W
If the 50 is cranked however a 100 watt JMP Marshall can have a peak watts up to 175.
A 50 watt cannot.

The watt (symbol: W) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m2⋅s−3. It is used to quantify the rate of energy transfer.
 
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