I took a different approach to controlling unwanted sound in my van - I now wear sound-cancelling earphones. They are very effective at cutting out road roar and engine noise , and I find driving long distances much less tiring now.
I can still hear sirens etc, but they would make conversations with passengers more difficult. Not a problem for me, I usually only travel in my van with my dog to agility trials, and I'm not very interested in her critiques of what I did wrong at the last trial
2017 MY18 Golf R 7.5 Wolfsburg wagon (boring white) delivered 21 Sep 2017, 2008 Octavia vRS wagon 2.0 TFSI 6M (bright yellow), 2006 T5 Transporter van 2.5 TDI 6M (gone but not forgotten).
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