I've got a different take on Sweet Room to @
mdconnelly but I'm looking at it from a very different angle to him and I think his view is definitely worth listening to.
@
PeterS says that Sweet Room may get rid of serious room modes. That is wrong because it comes from a mistaken understanding of what Sweet Room does but Sweet Room can improve the listening experience.
Sweet Room is Devialet's version of electronic room correction. What it does is to modify the frequency output of the amplifier to correct for the effect of room modes at the listening position. Electronic room correction does not remove the modes, they still exist in the room. Electronic room correction uses filters to cut the level of modal peaks at the listening position so that you hear those frequencies at the appropriate level but while electronic room correction can reduce the level of the modal peaks at the listening level it cannot increase the level of severe modal dips at the listening level in the same way because you simply cannot boost the level of those frequencies sufficiently to fill in the dip. Electronic room correction also has another limitation, its correction only works for the listening position at which the necessary measurements are made and for a small area around it, it may not correct the peaks for an area large enough to cover several listeners. The further someone sits from the position at which the measurements were taken, the less effective the correction becomes because the effects of room modes are not uniform across the whole room. Electronic room correction can also correct for non-modal peaks such as brightness caused by excessive reflection of high frequencies from surfaces such as glass in windows.
You can smooth out the modal response across the whole room to some degree by using acoustic room treatment but that has limitations also. Acoustic room treatment can reduce the level of modal peaks and raise the level of modal dips but unless you go for treatments designed to specifically correct for your particular room's modes you won't get as good a correction for modal peaks at the listening position as electronic room correction can provide although you will get better correction of modal dips than electronic room correction provides. In addition, acoustic correction of room modes will not correct for problems like brightness from high frequency reflection off surfaces like glass, that requires a different sort of acoustic treatment.
I'fe got 2 systems in my house. My audio system where my Devialet resides is in a room used only for listening to music. That room is acoustically treated. I have an AV system in my living room where I use Audyssey electronic room correction in an AV receiver to provide correction at the listening/viewing position. Sound quality in both rooms is very good but each system has what I'll call its own acoustic "personality" at the listening position. If I'm listening to music I definitely prefer the audio system setup with acoustic treatment, it sounds more "natural" and open to me than my AV system does. If I'm watching video I have no complaints at all about the AV system, in part because the visual input is dominant and the sound, while important, is not prioritised by our brains If I didn't have the audio system in a different room I could be happy with the AV system as a music system if I moved my Devialet and my music speakers to that system and set up Sweet Room..
To sum up that description in a simple statement, electronic room correction works by altering the amplifier's output to correct for the effect of the room. Acoustic treatment modifies the effect the room has on the speakers output. There is an area of overlap in what both sorts of correction provide but neither approach is "perfect" and each provides a listening experience with a different "character".
When it comes to listening my preference is for acoustic treatments but what treatment you install and where you install it has a big impact on the sound you hear. Many of my acoustic panels are on stands so I can move them around the room and that changes the sound at the listening position in many ways other than just the change in the frequency response you hear, it can change things like soundstage width and depth in ways in which electronic room correction can not. Acoustic treatment also involves installing panels around the room and those panels tend to be very visually noticeable plus they have to be placed in specific places in order to get the effect you want. That's not a big problem in a room dedicated specifically to listening to music but it is a big problem if you want to treat a living room which is used for purposes other than listening to music and/or watching video. I've heard it said that you get the best results from using a combination of acoustic treatment and electronic room correction and I think that's true but you can use electronic room correction in any room while you may very well not want to use acoustic treatment in a room like a living room because of its visual impact on the room and because placing it in the room for maximum benefit interferes with the way you want to use the room.
Whatever approach you want to use, you're going to get the best results by starting with speaker placement and where you put the listening position. Both of those things have a big effect on your listening experience and the better you can make your experience by addressing those things, the easier it will be to get better results regardless of whether you then choose to add acoustic treatment. electronic room correction, or both.
@
mdconnelly said that he didn't think electronic room correction is worth $3100 and it isn't if you can get a result you're happy with by simply moving your speakers and/or your listening position. It's also not worth it if you can get a result you like by using acoustic treatment for a lower cost than the cost of Sweet Room or if you can get it for a lower cost by upgrading your speakers to a different sort of speaker such as a panel, an open baffle, or a horn loaded speaker which loads the room differently than the speakers you currently have. There's a multitude of ways to correct for frequency response concerns at the listening position but they all have costs, both financially and in terms of the time and effort you spend in getting your setup to the point where you're happy with the result but the point is that you're trying to get it to a result you like. There's no such thing as "perfection" when it comes to what you like and what you like is not the same as what everyone else likes. The more people you share the house with, the more compromises you have to accept if you need to get a result that every one in the house is prepared to live with.
It may be worth it to the original poster to spend $3100 in order to get Sweet Room but he may be able to get a lot of the benefits Sweet Room offers simply by moving his speakers and/or his listening position or simply by doing things like adding a rug on the floor between the speakers and the listening position, moving a couple of items of furniture, drawing the curtains or closing the blinds over a window or two, or even buying a couple of bass traps to stick in the corners of the room for less than $3100.
And there's one other factor specific to Sweet Room to consider and that's whether or not he's using SAM. If you're not using SAM you can use 9 separate adjustments in Sweet Room for each channel, if you're using SAM you can only use 5 adjustments per channel. You can get from Sweet Room is less if you're using SAM than if you're not using SAM and, depending on how much correction you would need to apply with Sweet Room in order to solve all of the issues you want to correct, Sweet Room may not be capable of meeting your needs.
That's a long response but the benefits Sweet Room can provide are very dependent on your particular room, your speaker placement, where you put your listening position, whether or not you're using SAM, and what kind of sound characteristics you're chasing. Sweet Room may well be worth $3100 to one person and nothing at all to another.
