2007-11-16 3:38 pm
hey guys,

here is my attempt at a +-35V power supply, it is a a mix of a couple different designs i've seen around.

Please critique/offer suggestions!


  • +-35v transformer.jpg
    +-35v transformer.jpg
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hey guys could anybody tell me how many amps power supply should i buy for +- 35v and 100 w power output subwoofer amplifier
Don't try to work out the amps demand.
All the transient demand of the amplifier is met by the smoothing capacitance and the amplifier decoupling.

The transformer only has to be sized to not overheat on "Party" use and to hold a reasonably small range of voltage over a wide operating range.

The easiest method is to adopt a transformer size that is directly related to the maximum power of the amplifier.

A 100W ClassAB amplifier will run well from a 100VA to 200VA transformer.

100VA 35+35Vac transformer is effectively a 1.4Aac transformer.
200VA 35+35Vac transformer is effectively a 2.8Aac transformer.

Two channels running off a common transformer, would work on a transformer from 200VA to 400VA.

However, what does this mean?:
do you have a 100W into 4r0 amplifier that requires +-35Vdc when fully loaded, or +-35Vdc when in the quiescent state, or do you require a 35+35Vac transformer to power a 100W into 8r0 amplifier?
Don't be ambiguous.
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