Vibration isolating main ducts from furnace?

A recent post on soundproofing reminded me to ask this....
I'll probably need a new furnace for this winter. I was thinking of asking the installer to mechanically isolate the main duct hookups (return and output) from the furnace. So that the vibration of the fan does not transmit throughout the house ductwork. Also have the furnace itself set on an isolation mat to prevent vibration transmission to the floor.
Do any HVAC installers here have any experience doing this?
Would the installer simply use maybe a 6 inch length of large flex duct to make the connections to the main ducts? Or is there a rubber band of some kind that can be inserted to isolate the duct work from the furnace? To achieve a vibration break.
I have an audio listening/recording studio, so would like to eliminate the need to shut off the furnace when recording. Currently the furnace transmits a fairly high amount vibration into the ducts. I'll also be ordering the quietest furnace I can find.
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I have seen noise isolators for furnace ducts, a rubber connection. any good HVAC company should be able to help you spend more money:)
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*Lots of things can be done to reduce the sound transmission of your furnace. There are flex duct connectors. When I worked on TV studios they would go all out to reduce noise as they wanted the A/C running during production. Duct liner inside the ducts helps. Oversize ducts keeps the wind noise down. The only limitation is your wallet. You may want to use an installer who has experience with this. There are consultants who can make specifications and drawings for you to pass on to your installer.
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RickH wrote:

Isolate ducts with canvas type membrane? Cut out a section and replace with canvs membrane properly ribbed or framed.
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You need a canvas connector at the supply and return ducts at the furnace . For air noise control at your Studio outlets, you need to run flex duct where possible and if it meets code in your locale. Also, instead of running the supply/return ducts for the Studio in a straight pattern back to the Furnace Trunk Ducts, put a couple of deliberate turns in them which will reduce noise . When the Installer does the furnace, tell him to set the blower speed on the lowest possible settings while still satisfying the temperature rise specs listed on the furnace.
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RickH wrote:

Instead of setting the furnace on an isolation mat, consider hanging it from the rafters with springs. Any vibration will be transmitted to the outer walls via the rafters.
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If a brand new furnace has so much vibration that isolation is needed, something is very wrong. In other words, nothing other than a normal install should be needed.
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On Aug 1, 2:04pm, snipped-for-privacy@optonline.net wrote:

That all depends on one's tolerance level. I have a house full of musicians living here (me, kids, wife, and my oldest ones band)... Try recording sound with a furnace runing, you would be very surprised at how easily it finds its way onto the recording, microphones are very sensitive. I'll never get it to 0db but nonetheless the ductwork is usually the biggest source for transmitting the fan noise.
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Do you have physical shock mounts for the mics? Best to start there.
http://www.heilsound.com/pro/products/shock.php
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Of course. The noise is in the air, the air sound alone is picked up, the additional duct sound is aded on top of that. Shock mounts for mics keep the mics themselves isolated from their stand and the floor vibration, they do nothing for actual noise in the air.
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On Aug 1, 2:04pm, snipped-for-privacy@optonline.net wrote:

No, not necessarily. Vibrations or buzzing sounds can be transmitted thru sheetmetal ducts ; when possible, duct isolation is preferred. Some people arent bothered by it, but, potential Buyers of the home down the road might be .
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RickH wrote:

Fiberglas duct board for HVAC duct is pretty quiet and you may ask your HVAC installer if your blower motor will run at the slowest speed setting without overheating the combustion chamber in winter or freezing up the AC evaporator during the summer. Many of the more modern home HVAC systems have the new electronically controlled variable speed air handlers and they are very quiet. Other posters have already mentioned flexible duct segments. I have used anti vibration pads that can be cut to size and are available at the HVAC supply houses in my area:
http://www.vibrasystems.com/?EC=Product&ProductIDu
TDD
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How about going in a different direction. If you don't also need A/C then how about a small boiler and radiator, or hydronic floor in the music studio. Or even electric underfloor just for the studio.
David
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I've seen, and helped use some black flexible stuff, don't know the name of it. Also not sure how well it works as sound deadener. The air blowing through the vent grilles will also make some noise.
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