Home amp into res. load

[Richard Keller]

If I want to use a consumer stereo amplifier to drive a purely
resistive load, rather than a speaker, what factors should be
considered avoid damage to the output stage?

How can I maximize power output without choosing a too small value
resistor?

Richard Keller

 

[Jamie]

If I want to use a consumer stereo amplifier to drive a purely
resistive load, rather than a speaker, what factors should be
considered avoid damage to the output stage?

How can I maximize power output without choosing a too small value
resistor?

Richard Keller

Just select R load that is equal to what the amp is rated for.
4 or 2 ohms for example.


And make sure the load can handle the power and also, many
consumer amps will not operate at max level for long periods.
You may want to check that in the spec's of the amp.

 

[Richard Keller]

Just select R load that is equal to what the amp is rated for.
4 or 2 ohms for example.

Isn't the loading also dependent on frequency in accord with speaker
impedance?

What if the single audio frequency I want to apply is in the lower end
of the audio range, say 60Hz, and steady not intermittent like music?

Do I need a higher value resistor to compensate?

Richard Keller

 

[Phil Allison]

"Richard Keller"

Isn't the loading also dependent on frequency in accord with speaker
impedance?

** Speaker impedances are all over the place - some are even resistive at
all audio frequencies.

What if the single audio frequency I want to apply is in the lower end
of the audio range, say 60Hz, and steady not intermittent like music?

** No problem.

But running at full power continuously will likely oveheat the transformer.

Running at or near half power will overheat the output transistors.



..... Phil

 

[Phil Allison]

"Vladimir Vassilevsky"

Keep in mind that the "rated audio power at rated resistance" of the
amplifier could mean absolutely nothing.

** A very cynical and false view.

You can probably count on sustaining of no more then 1/10 of so-called
rated power.

** A very pessimistic view, completely without justification.

Domestic stereo amps can normally deliver their rated power figures for long
periods, probably indefinitely if only one channel is driven.


...... Phil