Manufacturer: SilentAire, distributed by SilentAire Technology, 711 Rutland, Houston, TX 77007, 800-972-7668.
Price: $599
Comments: Refrigerator-type "silent" compressor, regulator.
Pros: Very quiet, easy to carry, well regulated.
Cons: No moisture trap.
The SilentAire Eco-Air 20, made in Italy, is a .7 cfm (cubic feet per minute) unit which uses a rotary piston compressor to develop up to 88 psi (pounds per square inch). The Eco-Air comes with a regulator and has both an automatic shutoff and a safety valve. Thanks to its relatively light weight (the shipping weight is 40 lbs.) and its clever combination tank/handle, it is easy to handle.
The Eco-Air 20 was extremely quiet in operation; the hiss of the air escaping the brush was far louder than the compressor. There was an audible "pop" whenever the automatic shutoff operated, however. Maximum working pressure will depend on how much recovery time the compressor has between sprays and how air-hungry your particular brush is. In the worst realistic case I could devise, the Eco-Air maintained 50 psi, higher than I ever use. At that pressure or below, the drop between the static pressure and the working pressure was only approximately 1 pound.
Hoses with an O-ring mated well with the regulator, but those with conical compression fittings leaked at the joint. If you need to use that type of hose, consider purchasing an adapter. Despite the lack of a moisture trap, I did not note any moisture in the air during my testing (using a clear hose and an in-line trap). While the Eco-Air's current draw is low on average, there is a substantial surge when the motor starts. The Eco-Air, like most silent compressors, requires oil to operate; the oil filler and the oil level sight glass are conveniently located. The Eco-Air is a robustly constructed, simple-to-use, and extremely quiet compressor that is appropriately sized for most hobby airbrushing needs. It's well worth considering if you're in the market for a compressor.
Terry Thompson