Hood quieting is a topic you should search for within this forum (google directed at ths.gardenweb.com can be a good filter). In short, best noise suppression results from these feature incorporations:

o External blower (an in-line blower at the external end of the duct will also work)
o Duct diameter on the larger diameter side of the 1000 - 2000 ft/min desired duct air velocity rate
o A larger blower than normally needed run a lower speeds will be quieter)
o In-line silencer/muffler (see Fantech's web site)
o Baffle filters

Of course, all the other often-restated requirements apply, such as island/peninsula hood oversizing to capture on all four sides, 90 cfm actual (around 135 cfm rated) blower capacity per square foot of hood aperture. You will need a passive or active source of make-up air (another search topic).

All the above are met by my Wolf Pro Island hood, although mine is longer than you need because it covers both a 36-inch induction cooktop and a 3500W Cooktec induction wok hob.

And the underlying but unavoidable requirement applies that you can choose any two of performance, economy, aesthetics.

kas

Thank you kas!

The Fantech duct silencer mentioned by kas does a great job of reducing noise from the remotely mounted (on roof, or in attic) motor/blower. You will not get away from the noise of air flow though the hood baffles/screen, but blower noise will be pretty much gone.

If you are in a cold-weather area, or have gravity gas appliances (old fashioned water heater or furnace, for example) in the heated envelope or fireplaces, you need to understand the makeup air issue. The concern is that you don't want to back-draft your chimneys/exhaust ducts with a large fan in a well sealed house. Colder regions tend to have codes restricting the capacity of exhaust fans, above which you have to provide "make-up air" from outside. From a practical viewpoint, you can just open a window when using the fan at full blast, but regulations will not allow that. Here in San Jose, the two largest fans (hood, bathroom) combined cannot exceed 15CFM per 100 sq ft of house size without makeup air, if there are any gravity devices -- so I moved my water heater to a closet sealed from the house/vented to the outside, and my furnace to the vented attic.

A good point is embedded in attofarad's comment (promoting him to a picofarad).

The likely lowest cost method of dealing with make up air (MUA) and not back-drafting appliances is to seal off the appliances and provide simple MUA paths to them (ducts and dampers or just dampers in a wall opening). Then the main house MUA can have a little higher pressure drop than otherwise tolerable for safety. This can eliminate the need for an active (blown) MUA system. There will be less overall hood flow rate with greater house negative pressure induced by an MUA duct with a filter and heater, but in most cases, this may be tolerable. And where maximum fume removal is needed, the open window approach is always an option.

Fireplaces are also gravity combustion devices where the draft depends on very modest pressure differences between hearth and chimney top. An unblown MUA system supplying a large kitchen hood flow rate will probably not allow simultaneous use of a fireplace, or at least of a damped glassed door fireplace. A really roaring blaze would be needed to exceed anticipated house negative pressure.

kas

Anne, what hood did you pick? :)