Small bends will have very little effect. Even a 90 or two would not be a huge deal for 10" duct at 1200CFM, but avoid if you can. If you have a roof-mounted blower, things will get more quiet if you can move it further away from the hood. The adjustable elbows have sections to turn, and adjust anywhere from 0 to 90 degrees. Here is a link that might be useful: Duct elbow (adjustable)

Concerning more ventilation: Most of the time it's fine. I don't mind cooking smells in the house. I've never cooked fish or something with strong unpleasant odors. The only times I really want more is when I'm sauteeing onions or searing steaks and I get smoke going. I turn it on in those cases but it doesn't even have enough pull to really pull the smoke up to the vent if that makes sense. Also I have greasy build-up on top of my cabinets. I had no idea that a fan was even suppose to be used for greasy things (can you tell my mom never used hers either), so now that I know a fan could help with that it would be nice if I had one that worked better so I didn't have to scrub the top of my cabinets every year. As far as current venting goes; if I had any it would have to be in the existing wall, nothing goes through the cabinet over the stove. Also there is nothing on the roof or side of the house that indicts anything being vented anywhere in this area of the house. Weedmeister, after reading your message I realize I was incorrect in my thinking of where the duct connects to the hood. I was thinking they would connect to the back side of the hood (where it touches the wall) but after reading this I think you are saying the duct will connect above the hood. Is that correct? In that case I'd have 2 turns in either direction (one from the fan to the wall and one from the wall to go up or to the side. I'd definitely want the vent in the wall because I have a huge open space above the cabinets up to the cathedral ceiling and I wouldn't want to see a vent running there. Thanks for helping me clarify this stuff. More and more it sounds like going ductless might still be my best choice. The filters on them were rather expensive and I was starting to think maybe over the long term that just installing the ducting work would be cheaper than replacing all those filters. So if I'm going to install a ductless hood, does the CFM's matter so much. I was considering the Broan Evolutions QP130 or Broan QP230 hoods.

Sorry if I was unclear, but the silencer removes noise that is beyond the silencer relative to the listener. So, not that it would matter, but hood baffle noise would be partially silenced when listening on the roof. Relative to the cook in the kitchen, the silencer removes noise beyond it. So, hood baffle noise and local duct noise and local hood interior transition noise won't be affected by the silencer when listening at the cooktop, but duct noise on the roof side of the silencer and most importantly blade tip turbulence noise from the roof blower or the in-line blower that is past the silencer (relative to the hood) will be attenuated when listening at the cooktop. The blower noise is typically the loudest, so the silencer is important to minimizing noise. (It is worth pointing out as I think I did sometime in the past that blade tip turbulence noise dominates baffle noise given well designed baffles. I only have personal experience with my Wolf/Independent hood, so it is possible that a particular baffle design could be noisier than a particular blower design.) So the silencer should be as near as feasible to the hood (past any dampers), and the motor closer to the roof or on the roof. A duct that passes heated rooms should be insulated from the rooms passed, and possibly partially coated with damping material (I use automotive sheet metal dampener sheets). A damper is needed at the hood (probably part of the hood) and another should be at the roof. The Wolf/Broan low profile blower I have has its own damper which opens upon flow. Abbaka and Broan blowers look similar and appear to use the same approach. An upblast or downblast quasi-commercial blower and housing design may need a conventional damper just below it. Dampers should be checked for function without hanging up on errant screws before workmen can escape the project. A straight run will have minimal duct bend turbulence noise (caused by flow separation, perhaps). It may or may not make adding a silencer inconvenient, architecturally. kas

A couple of additional considerations for the op. 1. "Prostyle" encompasses a couple of other design/layout features besides having four full-range, large burners: (a) the burners are spaced a couple of inches wider -- 11 inch centers (front to back) as compared to 9" on non-pro-style ranges) and (b) they have thin backsplash/oven vents at the back or (if not placed against a wall) have island trim. These two features mean you have space to run four very large pans at a time, if that is the kind of production/entertaining-cooking you do. This is something you cannot do with most standard freestanding and slide-in ranges. WIth freestanding ranges, it is the thicker vent/backsplash that limits the size of pots on the back burners. With slide-ins, it is the more constricted burner layout. (Major brand slide-ins often have a bit less usable cooktop real estate than freestanding ranges even though the look more open. 2. The GE Cafe ranges are kind of an exception to these restrictions. The space at the back of the Cafe stovetop is a thin forward-angled, low rise oven vent which does give you more room for pots than with a standard freestanding range, The burners (IIRC) are still on 9 inch centers and, as you welll know, the back burners are rather wimpy. Also, if you are planning on putting your Cafe stove against a wall, you might want to consider buying the accessory vent riser that GE offers. It puts oven venting a bit higher, keeps stuff from rolling off the stovetop into the oven vents, and helps shield the back wall from some of the worst goop and condensates. 3. You say you have crossed the NXR off your list because "the quality seems to be suspect." I take "suspect quality" to be a concern that substandard parts are used resulting in an unreliable, short-lived appliance. If that is what you meant, you have crossed off the NXR for the wrong reasons. It is not the "quality" of the NXR ranges that is "suspect" but, rather, the company's (Duro's) warranty service and support. The build quality is a well known quantity -- at least comparable with similarly priced Electrolux/Frigidiare, GE, Whirlpool, etc. ranges. The NXR's operating components are sourced from well respected, reliable makers who supply the same parts to other stove makers. The problem with any line of manufactured products is the simple fact of life that everybody's production lines kick out some lemons and some stoves of every brand and model can and do turn up with shipping damage. As far as anybody can tell, NXRs do not have any more instances of shipping damage or lemons than most other brands.Most people who buy NXRs get good ranges. That is where we talk about warranty service and support and that is where NXR/Duro can be sketchy. It is not just NXR/Duro, though. For many manufacturers with small-market shares, warranty service can be bad and sometimes has been outright terrible. That is, in fact, a serious consideration for anybody considering any pro-style ranges. Research Blue Star and you will find numbers of complaints about similarly bad service for those ranges. This is not said to defend NXR but to point out a market reality that has to factored in to the decision to purchase any pro-style range from any maker with a small share of the appliance market. BTW, the fact that you can find a lot more complaints about Blue Star than NXR is not important. Blue Star has simply sold a lot more stoves for a lot longer than NXR. As you will find from searching threads here, a large majority of the Blue Star buyers have very well satsfied. Again, the problems have not been so much with the overall quality of the product as with the support and service. There is another aspect that may dampen the number of NXR complaints, which is that many of us buy or bought our NXRs from Costco. Costco has an iron-clad, full refund, customer satisfaction guarantee. That means that, if I receive a lemon or stove with shipping damage (that is, damage was not obvious enough for me to refuse the delivery), I don't have to wait for the endlessly delayed, multiple warranty service visits that get reported for just about every brand of range. Instead, I just take my range back to Costco and get a full refund. I can do the same thing if I just decide I don't like the stove after several months of use. Obviously, this is going to appeal to some people and not to those who lack the interest, ability or means to schlep around a 300 pound range. 4. When I was stove shopping several years ago, I was seriously interested in a GE Cafe dual fuel range. I don't know if you found it in your searches, but we had a thread discussing the pros and cons of NXRs, GE Cafes and other ranges in that price bracket. You might find it useful if it didn't turn up in your searches. Here's the link: http://ths.gardenweb.com/forums/load/appl/msg0123491328448.html