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I'm using an Inspire 2.1 2400 audio set - https://www.cnet.com/products/creative-inspire-2-1-2400-speaker-system-for-pc-2-1-channel-21-watt-total-black-series/specs/

The set comes with a 12V-1.5A transformer, and I just connected a same-voltage-lower-ampers (12V-1.0A) transformer into it, and everything works pretty much the same..

Does it make any internal damage? What's the actual effect of lower ampers?

Edit:

Choosing power supply, how to get the voltage and current ratings?

doesn't really answer my question .. I asked what happens if I plug in a lower amperage transformer.

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J. Doe
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  • Possible duplicate of [Choosing power supply, how to get the voltage and current ratings?](http://electronics.stackexchange.com/questions/34745/choosing-power-supply-how-to-get-the-voltage-and-current-ratings) – Olin Lathrop Nov 26 '16 at 14:56
  • Off topic. Not related to electronics design. –  Nov 26 '16 at 15:42
  • @Wossname where do I ask it then? It is also off topic in Physics, even when tagged for electricity. – J. Doe Nov 26 '16 at 15:43
  • The page you linked to says it has a DC input, so the supplied mains adapter would have output DC. As long as you don't turn the volume up very far (say, no more than half way), it will be fine with a 12 VDC 1 A adapter until you can get one of the correct current rating. – Andrew Morton Nov 26 '16 at 15:56
  • The answer by Olin Lanthrop in the "possible duplicate" post has a section "Current Limit" which answers your question. – Andrew Morton Nov 26 '16 at 16:27

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Most audio systems in this class use class AB linear power amplifiers. At very low volume this type of amplifier operates in class A, drawing a small constant current. At higher volume it changes to class B, where it only draws enough current to deliver the required volume to the speaker.

The Creative Inspire 2.1 2400 uses a TDA8410J, which integrates 3 class AB power amps into a single IC. The set comes with a 12V 1.5A power adapter because the manufacturer has determined it needs that much power at maximum audio output. At lower volume it needs less power, so a smaller adapter could be used so long as you keep the volume down.

If you try to run the amp at higher power than your power supply can handle a number of things may happen:-

  1. The power supply could overheat and burn out, or shut down due to excessive current draw.

  2. Its output voltage may drop, distorting the peaks of the audio waveform.

  3. There may be increased mains frequency 'ripple' or hum which becomes audible at high volume.

Bruce Abbott
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