Re: Preamps, tubes, valves ..... wtf!

FLY135 wrote:
chrisdude911 wrote:

Hey guys,
I am confused about Preamps, Cabinets and tubes.
What does a preamp do without a cabinet?
When it says that a preamp is 120 watts does that mean the amount of
power that it can give to the cabinet?
What is a tube?

As you can see i am a confused puppy!


1) No preamp is 120 watts. However an amp can be 120 watts
2) Cabinet = box with or without speakers installed.
3) Combo = preamp + power amp + cabinet w/speaker
4) Head = preamp + power amp
5) Valve = Tube

Sometimes a preamp is used seperately to amplify a low level signal to
drive something else. Sometimes an amp head or combo has connectors to
seperate the pre-amp and power amp. The FX out and FX in jacks would
do that. Sometimes the pre-amp and power amps are integrated as a
single unit.

Tubes are used as components of preamps and power amps. The
alternative to a tube is called "Solid State". Tubes have tonal
differences that make them often preferable to solid state. Solid
state means transistors/chips instead of tubes.

When an amp says 120 watts it's an approximation to the power that can
be sent to a cabinet when it's cranked up to high volumes. If the
power rating is RMS (root mean square) @ a specified THD (total
harmonic distortion), then it's the max power of a "clean" signal. If
the amp is distortnig then the power can go much higher. You can blow
out higher wattage speakers with a lower wattage amp because an amp
sending a distorted signal can exceed it's power rating.

actually, that 120 watts sounds more like the particular device's power consumption, not its potential output.
.

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