Speakers

[boylesg]

Do speakers have a voltage limit (as opposed to a power limit) beyond which they will not accurately reproduce the audio signal?

Or are they only sensitive power input where the voltage level is irrelevant, as long as the current is small enough so as not to exceed the power limit of the speaker?

 

[alexan_e]

Or are they only sensitive power input where the voltage level is irrelevant

How exactly can you apply more voltage to a speaker without increasing the current it consumes (and the power)?

You mean if the power specification can be rewritten as a max voltage?
Probably if you refer to a specific frequency like 1KHz and the impedance at that frequency is known so that you can do the calculations.
The problem is that the speaker may have a mean impedance of say 8ohm but in the audio range it is not stable at all

For example
**broken link removed**

 

[boylesg]

How exactly can you apply more voltage to a speaker without increasing the current it consumes (and the power)?

You mean if the power specification can be rewritten as a max voltage?
Probably if you refer to a specific frequency like 1KHz and the impedance at that frequency is known so that you can do the calculations.
The problem is that the speaker may have a mean impedance of say 8ohm but in the audio range it is not stable at all

For example
**broken link removed**

I am learning all this stuff from a failry low base.

I am trying to figure out why the following circuit does not work that well with an ipod and 8r speaker:



If I have the pot at the top/bottom its range - I am not sure which as I have not measured the resistance of the pot when the sound quality is good - the sound quality is pretty good. But as soon as I twiddle the pot the sound becomes very scratchy and staticy. The circuit is running off 24V.

Do you have any suggestions as to what might bbe happening?

Sorry R6 is actually a pot in the real circuit.

 

[alexan_e]

LM358 is an opamp with a max output current of 40mA , it can't do much to drive low resistance loads.

 

[boylesg]

LM358 is an opamp with a max output current of 40mA , it can't do much to drive low resistance loads.

Oh! Didn't pick that up in the datasheet for what ever reason.

So scratchy sound is not only caused by clipping due to high gain and too low voltage supply then?

That means it would probably work much better attached to a complementary pair then.