A few weeks ago I made the change of earpads in my QC35 headphones. These are the earpads that I buy in Amazon (of the same color):
In the product description (Amazon) it says that there are compatible with QC2, QC15, QC25, QC35, AE2, AE2i and AE2w. I think that these earpads they are less broad than the originals, but they remain comfortable. The problem is that I have the feeling that the ANC effect it's not that good that when I had the original earpads, I can't hear the white noise, despite that I have tested diferent firmware versions and reboot headphones. Maybe these earpads reduce the ANC feeling because they aren't the same as the originals. Or maybe something worse, the ANC circuit has been altered during the remplacement of earpads.
Buying a original set of QC35 earpads can be the solution?
I'm sorry the third-party replacement earpads aren't working out for you as you had hoped.
If you look at the Bose Headphones Accessories page there are different replacement cushion kits for different models (eg QC35 QC25 QC15). It seems unlikely that something sold as a replacement for several different models would work for all. I inquired about interchangeability of cushion kits for my QC25. I was told to get the earpads for the specific model I had.
If you want a direct replacement that was engineered to work as well as the original part, you want to get something you know came from Bose. The cushions are a critical part of the noise cancelling experience. They must provide passive noise suppression and a good seal.
Are your QC35 less than a year old? If you felt the original cushion kit had failed, you may be able to get the replacement cushion kit from Bose. You can follow this link to Bose product support for your area
Click your country, then scroll down until you see local contact information. I would call them.
Thanks for your reply @ST.
Unfortunately the Bose Service in Spain it's very poor. In the accesories there isn't a cushion kit replacement for QC35 and you can't contact with Bose Spain since some years because the contact page version is from 2015. Last year I had to replace my QC35 because power button was defective, I tried to contact with spanish Bose support, but I would get an error in the contact page. Fortunately Amazon Spain service it's awesome (nothing to do with Bose Spain) and they replaced my defective QC35 for my actual set.
I have to admit that maybe I have made a mistake buying this earpads. So I hope buy in Amazon the original QC35 earpads soon.
I am so sorry you have had such hard time getting Bose support in Spain. Thank you for telling me.
I'll make sure the right people hear about this.