Continually get impressed by the Polk TSI speakers.

I thought about upgrading the main fronts, but sonically I can honestly not find a reason to do so. These 5-1/4" woofer/1" Soft dome tweeter speakers sound really good.

I just keep getting impressed with these speakers. I have Amazon Unlimited which includes High Resolution Audio if you use one of the lastest Fire TV streamers. Other streamers may offer HD (CD quality at 16 bit/44.1Khz or 48Khz) as my older Fire TV stick which is also much better than compressed MP3 audio.

I was listening to Oh Daddy, by Fleetwood Mac on the Rumors Album on Amazon Unlimited in 24 bit/96Khz High Definition and man does this sound good. The imaging and sound staging (which simply sucks on MP3 or compressed audio) really shines on the TSI100 bookshelf speakers. I have the speakers towed in to the listening spot and the soundstage with precise imaging is excellent, went well beyond the speakers by about 5 - 6'. Sounded absolutely amazing. With the TSI100 tonal characteristic, I just love listening to music on these speakers. Not bright or fatiguing or dark/warm and veiled, to me these speakers sound neutral and have tonality close to Polks upper end bookshelves.

The bookshelves are not small for their size. They are deep and heavy so while I could put another pair on the wall, I'll stick to my smaller and much lighter Infinity Entra .5s and Primus P143 little speakers.

Cheap Audio man did a review on these TSI100 speakers and raved about them compared to speakers 2 or 3 times their price.

While some disagree, these speakers seem to become even greater sounding adding the Polk DSW Pro 660wi subwoofer to add low bass to their sound compared to my now dead Velodyne CT-100 subwoofer.

For what it's worth, $8/month for High Definition audio from Amazon Unlimited is well worth the price IMO. The music sounds so much better than compressed streaming audio, and offers significant benefits over CD quality audio. They also have a large library of music which makes finding new artists to listen to inexpensive. The downside is that Fire TV sticks suck next to Roku but you only get UHD audio (High Resolution) through a Fire TV stick or Mobile device w/headphones. My 3 Fire TV Stick 4K Max streamers are so unreliable is crazy they were even sold. Constant power cycles and reboots so they can function like they should. However they're the only High Resolution Audio game in town, so taking the Awesome with the bad seems worthwhile.