[Ianhp1]

I have heard both the resonated and the non resonated versions of the Milltek "in person" and I left scratching my head. Both do not justify any reason in my opinion to upgrade your exhaust. Barely tell the difference over stock. I am still debating on the GMG or AWE with or without the downpipes. I can tell you if it doesn't have an audible difference its going on ebay!!

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Here's the difference in sound VERY CLEARLY on my own car before and after fitting, recorded with the same equipment on the same day with all the same settings:

http://www.youtube.com/watch?v=FsIJPIyrgmw

BTW... Milltek do not do a non-resonated version for the S5 yet, so I can't see how you can comment on that one.

Finally, to answer the original question:

The Milltek does make the cabin noise more noticeable, which is great! When driven with the windows down it's just awesome! However whilst it is quiet-ish when cruising it's not silent. Below 2K revs it does 'boom' too. Unfortunately you can't have it all!

 

[Ianhp1]

Just revving isn't enough. You have to hear the exhaust under load while down-shifting to really hear the difference.

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Gotta agree with this... it bellows onder load. revving makes a difference, but nothing like when driven... even moderately gently. The overrun sound is awesome too!