After buying the 991.2 C4GTS, I realized that the audio quality was quite sub par. I looked into a full audio build. Decided not to do that for many reasons. After reading up that others too felt the Bose system was lacking, I decided to do a tweeter upgrade. I made up a set 4ohm Dayton Audio tweeters for my 991.2. These installed in the factory position using Bose grilles and requires no modification. Just unclip the Bose speaker and clip these in. Simple! I made a similar set for friend with a 718. Sound quality improves significantly with this tweeter upgrade since the Bose tweeters are very poor quality and are so shrilly and piercing. After the install these you will notice the improved sound quality and ability to turn up the volume considerably since the very poor quality Bose tweeters are no longer limiting the output. These are plug and play in the 991.2. In the 718, the flat base needed to be removed with a bench grinder or Dremel. All wiring was properly soldered, shrink wrapped and wrapped with fabric tape to minimize any rattling. I used audio foam to cushion the speaker under the factory Bose spring steel clip. Speakers disconnects are gold and are very firmly connected. A 12uF capacitor was soldered inline.
A few individuals asked me to make them up an identical set up. I made 1 extra set and am offering it up for sale here. This is a brand new wiring harness and 2 brand new speakers.
The photo with the Bose speaker grille shows how I mounted them to the factory grille without the need for modification. I used a large yellow capacitor in my original setup but changed them to a smaller 12uF capacitor in these harnesses. The last 2 photo show it after modification, in a 718.
Price is $225 shipped vis USPS with tracking.

 

Jack
I will take them.
Does this help improve the sound in the tinny Bose midrange and vocals?
Thanks!
JOHN

 

Makes a huge difference in the upper range. Much les piecing and less shrilly. Difference is really difficult to understand. But the Bose tweeters really are a limiting factor. After replacement you will be able to turn up the volume. Pm sent.

 

Can’t wait. Thanks jack

 

Please let me know if you decide to make more for a 991.2.

Jerry

 

This one is sold. Could make up a few more sets if there is interest. Just need to know how many sets would be needed. Thanks