What voltage are the koss 'older' computer/CD speakers that would take 3 'C' batteries each. I have a variable voltage adapter and am not sure if I should switch it to 9 volt or another setting for AC power. I want to use it with my I pod.

I.m not familiar with the Koss speakers so I don't know how they are wired. If all 6 batteries are wired in series, you wouuld have 1.5 Volts X 6 = 9 Volts DC. If you have an AC voltage adaptor you cannot use it. If you have a DC voltage adaptor, 9 Volts MAY be correct for your I pod but you need to check with the I pod manufacturer to find out what the correct vloltage is. Also DC voltages are polarized + and - . If you connect the two wires from a DC adaptor backwards you could easily wipe-out your I pod. Get the voltage info from the manufacturer first and consider buying an inexpnsive multi-meter to measure your voltages with before you proceed.

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Best regards,
Yavacotech

Hi - the Koss HD50 will work with 6 C cells - 3 in each speaker or with a 9V power adapter.

Note however that the power adapter supplied with the speakers has the positive wired to the sleeve of the power plug and the negative to the central tip.

This opposite to the normal practice of positive to the tip and negative to the sleeve.

GDW

C cells are 1.5 volts each. If the speakers use three of them that means you'll need a 4.5 volt supply. If each speaker needs batteries, you'll need to feed that voltage to each speaker, and the supply should have enough current for the total load. A 1-amp rating is probably fine.