We have the Concorde waiting for other parts of our kitchen to be installed. When we tested it in our kitchen for checking the height, we were pleased with the noise and sucking power of the fan even tho it was just blowing out of the top pipe. The problem with this model is that it really needs to come down to be reachable for us vertically challenged types. I don't believe that will be a problem with the ones you have mentioned. The stainless steel does show fingerprints easily but is of good quality finish. We understand because our house is set up similarly tho I prefer the stereo on while cooking myself! :)

I only saw one Ventahood where I could try to figure out if the cleaning or the more raw underside would bother me, and it was not connected to power so I don't know about their sound level. I've heard they are quieter and I've heard they are louder. I think the looks of the cages vs baffles would be more of an issue for me. While I was trying to decide whether that was a bit "raw" looking, I was led to a guy at the place where I bought my appliances who said he'd seen and heard both side by side. He said the Best by Broan was better for sound and operation, so I went with it. Very scientific, huh? Unfortunately, buying a vent is like that. I have a 1200 cfm model with an external blower and got the baffles. The blower sits just above my sink on the opposite side of my kitchen (better than the toilet or shower straight above --LOL) and it is quiet when you are outside. I'm not sure that in my set up the remote blower made that much difference. If I'd have another inch or two, I'd have been able to put in a silencer. Most of the time, I run the vent on the lowest setting or up to about 1/3 power -- rarely over 1/2. At that level, the fan on my ovens is as loud. You barely hear it away from the vent, but you will standing right under it. At full power, you will hear it, but even then it is not as loud as the ineffective downdraft my last cooktop had -- with only one speed. If you turn it on when you first start cooking and run it higher for things like fish, popcorn, bacon, you will not smell them all over the house. I made 120 bags of popcorn, both on the stovetop and in the microwave (bags opened under the vent)one afternoon. I delivered them to the school, came home and could not smell any popcorn. Maybe it could be more perfect, but I'm happy with my choice.

On higher speeds, powerful hoods are loud. You're moving a lot of air through a relatively small opening. Some noise is inevitable and to a degree, you just need to adjust your expectations when you're coming from an older, less powerful hood. Hoods are very simple and there aren't that many design aspects that can be tweaked to reduce noise levels, compared with other appliances. There are things you can do though. What CFM, and what speeds do you usually use it at? The mid to lower ones should be fine for most cooking. If you mount the blower externally and add an inline silencer, that should help some with the noise, as that takes the turbulence around the blades and moves it away from the area right above your stove. All I'm saying is, I'd hate to see you spend a lot of money on something that doesn't fix the problem. Unless you change something about the design of your overall ventilation system, I wouldn't expect simply replacing it with something similar from another brand to make much of a difference.

Ah. My apologies for abusive engineering descriptions. Sometimes I tend to unconsciously assume that all the previous stuff here has been read and digested, so all I have to do is present a reminder. Capture: The plume expands as it rises. The actual expansion angle is greater than 10 degrees outward, but ten degrees encompasses most of the higher velocity components for relevant cases. This means that the cone is wider the higher one measures above the pan base. At 36 inches hood height, for example, with a tangent of 10 degrees equal to 0.176, the plume has expanded outward by 36 inches times 0.176 or 6.4 inches. Similarly, for 30 inches, the plume has expanded by 30 times 0.176 = 5.3 inches. (Exactness is used here to clarify the calculation, not assert a defined boundary exists at the plume.) Suppose a pan base's maximum extent from the wall was 19 inches (which would be true of my induction cooktop if it were against a wall). Then one should aim for a hood aperture that was 19 + 6.375 = ~ 25 inches from the wall if 36 inches up. A 27-inch hood with lights in front of the aperture is close enough. Hence, your drawings have the angle going the wrong way. Imagine a really large traffic cone (without it weighted base). Slice it where it is the same diameter as the pan base and invert it over the pan. This inverted, truncated traffic cone, or rather a set of them perched on all the burners or hobs, can be imagined as defining the required boundary of the hood aperture. The desired hood aperture for good capture is independent of whether the structure of the hood is all metal or is metal inside of wood. Depending on your configuration, it may be best to space a smaller hood outwards and fill the gap at the wall side with some sheet metal. Side cabinets can help perform the function of side curtains in commercial configurations. (Note re pillog's comment. There is a small zone of high flow rate at the edges of the hood, and this has the effect of a slight increase in effective aperture.) Containment: Your analysis is correct. If the aperture is 6 sq. ft., then the desirable actual flow rate at full power is 90 x 6 = 540 cubic ft./min. Now where did I pull the magic number 90 from. Briefly, there are studies that have been published of plume velocities as a function of surface temperature, with induction and with gas. The gas cooking velocity (because the gas combustion products are entrained in the plume) causes more than a meter per second of plume rising velocity. The velocity with induction is typically less than a m/s. At the pan, the hood has NO effect on the velocity, and this essentially holds until the plume is close to the hood aperture. Another way to put it is that the hood captures the plume due to the plume's upward momentum (mass times velocity), which will not change until accelerated or decelerated by some force. When the plume reaches the baffles, it can intercept a gap and pass into the baffle space, or it can hit a metal part and potentially reflect. To keep the reflection in check, the air flow velocity of the hood has to be enough to change the reflection momentum to near zero and let the plume part be pulled into the baffles. When the air velocity is 90 ft/min average across the baffle space, it is about twice that at the baffle gaps, and this velocity is equal to that of the plume velocity. Also, I have observed this level working for the plume over my induction wok, and Greenheck suggests 85 ft/min for similar cooking (Figure 4, page 9 of the previous reference). So think of 90 ft/min as a suggestion that I don't think will prove to be too low. Too low of a hood velocity (CFM/sq. ft.), hence too low of a hood flow rate (below). Enough velocity (below) Blower specification: Yes, the factor of 1.5 is used to make up for the fact that blowers are specified by themselves (usually) hanging in free air, and what you have is a restrictive system that has to deal with baffle restriction, duct, and make-up air pressure losses. The relationship is given by the so-called "fan curve." For example, the Broan blower fan curve immediately below is just about done at well under an inch of water column pressure. Your requirements, depending particularly on baffles and MUA, may require a more "powerful" (higher nominal CFM) blower, as in the second figure. If the only loss were baffles, then the first figure would be barely good enough, because the baffles might have a pressure loss of about one or two tenths of an inch, w.c., at 90 CFM/sq. ft., depending on their aerodynamics. Throw in ducting and pressure losses in the MUA system (a whole giant topic of its own), and the tenths of inches build up leading variously to a need for one of the higher nominal flow rate models.Ekes out 540 CFM at a very low pressure drop (above) A blower with the 1.5 factor achieved (above). Keep in mind 1.5 is only a guess. A blower that would make up for many installation crimes (above), but which drives an unnecessarily more expensive MUA system to keep house pressure up. kas