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Quiet HVAC for Audio Room options?

73hadd

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Hi all,

Forced air heat and cooling is a bit loud in my listening room.

I've seen reference to use of "mini-split" systems but I am not sure I am willing to go that route. Are they really very quiet?

I've also seen reference to removing/blocking duct work. Has anyone isolated the ducting for a room and used a BLDC motor running on a low speed?

I would think hot water/radiator heat would be very quiet, unless there are expansion or other sounds?

Any exotic options for cooling? I am picturing a cooled line running the perimeter of the entire room along the ceiling, cooling the air and allowing it to sink.

Any thoughts/options are welcome!
 

Webninja

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I looked into mini-split and having a wall mounted solo AC (Euro style) in my media room, but it all proved to be too costly. I was thinking of having a switch to block the one vent at the junction, just to turn off the air when I'm watching a movie or listening, but haven't researched the hole thing yet.

Being in So Cal, I'm lucky to not deal with extreme weather, so I wouldn't need heating/cooling in that room for the few hours I'd be using it.

Good luck.
 

tmtomh

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In my experience the main source of noise isn’t the blower - it’s the sound of the air traveling through rigid sheet metal ductwork.

If you’re able to modify your ductwork, forced-air HVAC can be made much quieter at the room vent by replacing the rigid sheet metal ductwork from the air handler (aka the furnace or heat pump) to your room vent with flexible foil ducting. You only need to swap in the flexible ducting on the “branch” that serves your room.

A minisplit can be a quiet option too, but only if you have an outside wall in your listening room. Otherwise you’ll have to have a ducted minisplit, which gains you nothing sound-wise as the ducting is the issue.
 

Webninja

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I think @tmtomh is spot on. The noise of the air is the culprit. I ended up with linear vents in the remodel, so air velocity sound is less than through a traditional vent, but I can still hear when it starts on/off.

Maybe the vent itself makes most of the noise and you could see if no vent cover alters the sound.
 

m_g_s_g

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Any exotic options for cooling?

I just make good use of my Ecobee Thermostat (would work with any other “smart“ one).

When I want to listen to music or watch a film I simply switch to another cooling/heating mode (“away” or “holidays”). I can do it from my mobile app, program my home automation system or just tell Alexa.
 

Webninja

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Uh, now I feel dumb for not thinking the same, since I have an ecobee and HomeKit integration. D’oh. I’ll remember to use that when I’m measuring speakers too.
 

Trouble Maker

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Uh, now I feel dumb for not thinking the same, since I have an ecobee and HomeKit integration. D’oh. I’ll remember to use that when I’m measuring speakers too.

There are also 'smart vents' that replace the vent cover that can open/close. Could be cool to have a 'music listening scene' and have the vent that is the culprit closes. I'm sure some of them probably work natively with HomeKit or ecobee.
'Smart' vents - https://keenhome.io/
Someone maybe also makes more traditional zone controls (motorized dampers that go inline with the ducting) that play well with some smart home systems.
HVAC Damper Controls - https://www.amazon.com/slp/hvac-damper-control/jqt7hv8gdsuj9f5
 
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suttondesign

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Hi all,

Forced air heat and cooling is a bit loud in my listening room.

Any thoughts/options are welcome!

We have recently installed the most expensive version of typical forced-air heating/air in our home, which involves an infinitely-variable-speed blower for our heat pumps. In practice, the blower runs so low now that the airflow from the outlets is inaudible. $14k for the downstairs, that much again for the upstairs, in a 2800-sq-ft house with very tightly insulated walls and attic. But it sure helps the media room quiet factor!
 

Trouble Maker

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I remembered this thread and was curious about the mini-splits in our apartment here.

The one in our spare room, which is currently my office while mostly working from home, is a Toshiba RAS-2219T. I doubt you can get this in the US, but it's just a point of reference. It has a 'quiet' fan mode which claims 26~27dB.

We are in a fairly busy area, in a city of about half a million. Close to major roads, construction and relatively close to the main train line. I'm facing the balcony with sliding glass doors and typical construction uses single pane windows here.

With the unit off I was just seeing an average of about 37dB and with it on quiet mode about 41dB (not sure about the weighting on this app).

My anecdotal feeling is that the unit is the loudest constant noise, with peaks from traffic being maybe louder but not constant. It feels like the fan is the loudest thing. I wonder if you got a mini-split but with not a wall unit and properly built ducting if it would be more quiet. Wall units are not the only option. My general plan is to use a horizontally ducted in the upstairs bedroom (attic crawl that it would fit well in) and if we go full non-mini split system a vertically ducted for downstairs. https://www.mitsubishicomfort.com/products
 
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tmtomh

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I remembered this thread and was curious about the mini-splits in our apartment here.

The one in our spare room, which is currently my office while mostly working from home, is a Toshiba RAS-2219T. I doubt you can get this in the US, but it's just a point of reference. It has a 'quiet' fan mode which claims 26~27dB.

We are in a fairly busy area, in a city of about half a million. Close to major roads, construction and relatively close to the main train line. I'm facing the balcony with sliding glass doors and typical construction uses single pane windows here.

With the unit off I was just seeing an average of about 37dB and with it on quiet mode about 41dB (not sure about the weighting on this app).

My anecdotal feeling is that the unit is the loudest constant noise, with peaks from traffic being maybe louder but not constant. It feels like the fan is the loudest thing. I wonder if you got a mini-split but with not a wall unit and properly built ducting if it would be more quiet. Wall units are not the only option. My general plan is to use a horizontally ducted in the upstairs bedroom (attic crawl that it would fit well in) and if we go full non-mini split system a vertically ducted for downstairs. https://www.mitsubishicomfort.com/products

Be careful about ducted minisplits - they work great and are fairly quiet, but the sound of the fan from a ductless minisplit is replaced by the sound of the air rushing through the ducts, which can be as loud or louder depending on the fan setting and the size and route of the ducts.

One option, if your building situation and local code allows it, is to use flexible ducting instead of the usual rigid sheet metal ducting. I know from experience that flexible ducting greatly reduces the sound of the air movement (and I presume also reduces the sound of the blower fan transmitted/bouncing off of the rigid sheet metal).
 

Neddy

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We have recently installed the most expensive version of typical forced-air heating/air in our home, which involves an infinitely-variable-speed blower for our heat pumps. In practice, the blower runs so low now that the airflow from the outlets is inaudible. $14k for the downstairs, that much again for the upstairs, in a 2800-sq-ft house with very tightly insulated walls and attic. But it sure helps the media room quiet factor!

Fascinating info to compare with (tho apples/oranges climate wise) & makes me 'feel good' about my systems :)

AC: wall mount (ductless) mini-split - @ $2500 installed. Cools the entire 2500 sq ft house well, if not to 'chiller levels, even yesterday (96 deg, 90% humidity).
Heat: Super high efficiency Triangle Tube gas boiler feeding (existing) finned copper pipe in-floor radiant (floors above, ceilings below).
About $8k installed. (Payback was less than 4 years!)

My last house had a high end variable speed furnace (not heat pump).
It was actually pretty nice, but I did not care for the 'first rush' of cold air it would push out every time it came on.
In floor radiant is the Way To Go for dead silent heat (& audio), as far as I'm concerned.

When I get a chance I'll try putting a db meter on my mini-split.
Thanks!
 
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