Question about 50W/100W switch...

[edi_87]

It doesn't make a HUGE difference volume-wise when you swich the amp (in this case Triamp) from 100W mode to 50W, does it?! But what about the tone? Is it different in 50W or 100W mode? I heard that in 100W m. the tone is way better, i cannot hear the difference, though.. What are your opionions?

 

[Xeromus]

Re: Question about 50W/100W switch...

I prefer to use my legacy on 50 watt mode

 

[Neeradj]

Re: Question about 50W/100W switch...

The volume difference is 5dB, and decibel is the right way to rate volume, not wattage, wattage tells you more about tone. So there's hardly any hearibly difference between 100 and 50W. If you had a 50 watt amp which you wanted to sound twice as loud you'd have to increase the wattage 10 times (I kid you not!).

People say 100W amps sound better because they've got more headroom, meaning they break up less fast compared to some 50W amps. A good comparison would be the Marshall DSL50 which has less clean headroom compared to the DSL100.

 

[aleclee]

Re: Question about 50W/100W switch...

I'd expect better cleans on the higher setting and better distortion on the lower setting.

 

[Davey]

Re: Question about 50W/100W switch...

The volume difference is 5dB, and decibel is the right way to rate volume, not wattage, wattage tells you more about tone. So there's hardly any hearibly difference between 100 and 50W. If you had a 50 watt amp which you wanted to sound twice as loud you'd have to increase the wattage 10 times (I kid you not!).

People say 100W amps sound better because they've got more headroom, meaning they break up less fast compared to some 50W amps. A good comparison would be the Marshall DSL50 which has less clean headroom compared to the DSL100.

what he said

 

[aleclee]

Re: Question about 50W/100W switch...

The volume difference is 5dB, and decibel is the right way to rate volume, not wattage, wattage tells you more about tone. So there's hardly any hearibly difference between 100 and 50W. If you had a 50 watt amp which you wanted to sound twice as loud you'd have to increase the wattage 10 times (I kid you not!).

Actually, the difference is 3dB.

 

[Grandor]

Re: Question about 50W/100W switch...

Correct. 3dB

 

[RCM78]

Re: Question about 50W/100W switch...

Your probably switching the power tubes fron pentode operation to triode operation.
This will change the headroom of the amp and also how the amp react's to your playing.

 

[Kent S.]

Re: Question about 50W/100W switch...

The volume difference is 5dB, and decibel is the right way to rate volume, not wattage, wattage tells you more about tone. So there's hardly any hearibly difference between 100 and 50W. If you had a 50 watt amp which you wanted to sound twice as loud you'd have to increase the wattage 10 times (I kid you not!).

People say 100W amps sound better because they've got more headroom, meaning they break up less fast compared to some 50W amps. A good comparison would be the Marshall DSL50 which has less clean headroom compared to the DSL100.

6db according to a generalized SPL (sound pressure level), and the difference is 3dB power wise. Power uses a 10*log, and voltage and spl use a 20*log, meaning that half the power is -3dB, double is +3dB; half the voltage or spl is -6db, double is +6db; tens times the power ...+10dB, tend times the voltage or spl ....+20db... and so forth .... Even so, to the ear it depends on a alot of things, and considering also that tubes will start to compress before actual clipping, depending where they are at you may hear a small volume difference clean, or maybe none, but yeah, headroom is the difference. I think the guy meant to say 6dB anyway instead of 5, also you increase the power, not wattage ... that's almost as good as the *amperage* term I heard ... uh, you mean current? Just call it a pet peeve of mine ...

 

[sanrafael]

Re: Question about 50W/100W switch...

db is a power measurement, as is the watt. The reason that 20*log is used for voltage is that power is proportional to the square of voltage, and so using 20*log for voltage gives you power. That is, 20*log converts the voltage to power as part of its effect. Thus the SPL is also power when expressed in db, and doubling the power will cause the SPL to rise by 3 db.

It is true that 3 db is not an overwhelming increase; but it will fill a larger room if that is what you need.

You should, ideally, be able to get the same distortion from the 100W setting as the 50W, but at a somehwat higher volume. In practice, the speakers probably will not sound exactly the same, and depending upon how the designer has implemented the power switch over and the preamp, it might require some fooling around to get the same overdrive.

 

[Kent S.]

Re: Question about 50W/100W switch...

dB is actually a reference to the ratio of one magnitude to another, not necessarily a power measurement (although you'd be hard pressed to find any other use for it today). It always references a difference, between two magnitudes ...whether it be a change between two, or a reference (such as SPL always referencing the present sound level to the threshold of human hearing 20upascals; or for voltage line levels, referenceing the present voltage to a reference level (the proverbial 1Vrms for dBV, and 775mVrms for dBu). The reason that SPL also uses the 20*log form is similar as to the case for voltage, the best way I've ever heard it described is as such ...
The force of air pressing against the resistance of an eardrum is analogous to to force of a battery pushing electrons against the resistance in a circuit ...
Same holds true for current ratios expressed in dB as well ... more than anyone wanted to know, but well you know ...

 

[sanrafael]

Re: Question about 50W/100W switch...

True, the vibrating pressure difference is analagous to voltage (or current); both square to give something porportional to power, and when you make an "analog" microphone, it is the voltage (or possibly current) that is analogous to the sound pressure (or possibly the air velocity in a ribbon mic). And true also, a log scale always requries a reference since "zero" corresponds to something like minus infinity which is a bit difficult to work with! Log scales make things easy to understand in some essential ways, but the introduce some annoying complexity as well. No one with any sense ever said life is simple.

 

[Kent S.]

Re: Question about 50W/100W switch...

Good point on all parts!
The following is for the general board to show how confused things ccan get ...
I was reading yesterday in a pretty accurate book ... And the author equated 0dBu as a power reference to 1mW?
No ... 0dBm is referenced to 1mW, which corresponds in use to the proverbial 600 ohm load ... which 775mV into it will produce 1mW.
0dBu references 775mV regardless of load... 0dBm only corresponds to a voltage of 775mV if the load is 600 ohms. While 0dBu is always 775mV( the u stands for unloaded; as the voltage is measured in an open circuit or very high impedance).
And he stated it to be a power reference, dBu (also seen as dBv in some older books, note the lower case) and dBV are voltage references not power, 0dBm is a power reference to 1mW of power, the voltage that is at *0*dBm varies according to the load. So even some books confuse the issues with typos.
Then there is the case in which the powers that be, simply don't agree on what should be what ...case in point. I was looking over some specs on two speakers (brands not important), when discussing speaker power handling capabilities one manufacturer stated *continous* is based upon average (average what they didn't say), *program* is based upon rms (the old rms *power* term), and *peak* is peak ... yet it only seemed about 2.5 times continous;then the other manufacturer stated that *continous* is rms, and that *program* is peak ... right, not!
I'll use Peavey as a good example of what they should do, PV rates *continous*, *program*, and *peak* ratings for their drivers ... whether the continous rating is driven from a sinewave voltage adjusted to correspond to an rms or an average value is pretty much not important. As all we need to know is that that is a worst case scenario, the program pretty much relates to the rms *power* thing so used by everyone ... fine it works, and the peak thing is self-explanatory ... but the confusion with the other guys ...shhhesssh!