(01-27-2015, 02:51 PM)stevec Wrote: All of my compressors have been belt drive, are direct drive compressors (usually) noisier because the compressor is driven faster?
Steve,
I agree with Ed. It is my understanding that direct drive is usually noisier. I believe it is related to the speed of the compressor. When I purchased mine the sales person steered me to the slowest compressor speed he had available ... about 750 rpm with a motor speed of about 1750 rpm. He also suggested I get a muffler for the intake system. His statements suggested that a large percentage of the noise is from the pulses related to the intake, not the actual compression of the air. A muffler and "less intake pulses per second because the speed is lower" does seem to make sense.
I do know that this compressor is orders of magnitude quieter than the direct drive oil-less that I had before. Mine is in the basement and it is quiet enough that we don't notice it anymore and guests rarely ask "what is that?" when it comes on. The fan in the attic that comes on when it gets hot or humid is a much bigger pain in the ...