Laptop speakers do not sound very good, especially the lower end laptop speakers. I am surprised no one has come up with a laptop with subwoofers..
I have put together a set of open baffle speakers as shown in the image. These are taken from a PC speaker set that has long been dismantled. The speaker reads 4 Ohms. Originally used with my LM386 amplifier board but the LM386 is just too much for the low volumes I need to use without disturbing anyone. This is extreme near field, and is better than headphones. In fact, low volume speakers are a real advantage in a working environment, where others cannot be disturbed by the music during their phone calls, video conferences etc.
Here is the question: can these speakers be safely connected to the output of a laptop or a speaker (many years ago there used to be unpowered PC speakers)? . I have used a set of unpowered speakers many years ago on my desktop PC which has long since either given away or broken.
It all comes down to impedance. The typical resistance of a earphone for phones ( I measured mine) is 30 Ohms. Now this is not the impedance, but can function as a lower limit for impedance, since the formula for impedance is:
Impedance = SquareRoot(Resistance^2 + Impedance^2)
Instead of connecting a 4 Ohm speaker across the phone jack output, I can connect a 30 Ohm resistor in series with the speakers, and maybe a capacitor to keep out extreme low end. I tried this, and the sound volume is acceptable when boosted with Audacity (bass and treble) and distortion is not really a problem.
Does this all make sense? Anything I have missed? Anyone use this?
I have put together a set of open baffle speakers as shown in the image. These are taken from a PC speaker set that has long been dismantled. The speaker reads 4 Ohms. Originally used with my LM386 amplifier board but the LM386 is just too much for the low volumes I need to use without disturbing anyone. This is extreme near field, and is better than headphones. In fact, low volume speakers are a real advantage in a working environment, where others cannot be disturbed by the music during their phone calls, video conferences etc.
Here is the question: can these speakers be safely connected to the output of a laptop or a speaker (many years ago there used to be unpowered PC speakers)? . I have used a set of unpowered speakers many years ago on my desktop PC which has long since either given away or broken.
It all comes down to impedance. The typical resistance of a earphone for phones ( I measured mine) is 30 Ohms. Now this is not the impedance, but can function as a lower limit for impedance, since the formula for impedance is:
Impedance = SquareRoot(Resistance^2 + Impedance^2)
Instead of connecting a 4 Ohm speaker across the phone jack output, I can connect a 30 Ohm resistor in series with the speakers, and maybe a capacitor to keep out extreme low end. I tried this, and the sound volume is acceptable when boosted with Audacity (bass and treble) and distortion is not really a problem.
Does this all make sense? Anything I have missed? Anyone use this?
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Like these: no impedance values given:
Sony SRS-P7 Portable Speaker System | Product overview | What Hi-Fi?
Wait: 6 Ohms?
Sony SRS-P7 Specs - CNET
Sony SRS-P7 Portable Speaker System | Product overview | What Hi-Fi?
Wait: 6 Ohms?
Sony SRS-P7 Specs - CNET
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