Wiim Pro Plus sounds just like my TV Headphones!

Hey everyone,

I recently joined this forum and I hope I'm not spamming or duplicating any threads.

After reading numerous positive reviews, I bought a Wiim Pro Plus to enhance my digital sound setup.

Previously, I connected my Sony Bravia A80J's headphone output (yes, I know it's not ideal! :D) to the aux input of my amp. With the Wiim, I'm now using the TV's optical out to the Wiim and then the analog out to the amp.

For a side-by-side comparison, I connected the TV's headphone output to the amp's tape input and started doing some A/B testing. To my surprise, with the volume levels matched, the difference wasn't substantial—maybe just a 10-15% improvement!
 

Here are the details of my setup: 
- Amps: Technics SU 8580 and Kenwood KR 4070
- Speakers: Heco Superior 700

I tested in two ways:
1. TV optical out vs. headphone out (using both Spotify and local FLAC files)
2. Spotify streaming from the Wiim vs. TV optical out

The Wiim sounds slightly softer, warmer, and the bass is a bit more detailed, and the TV sound a little more crisp and dry but the margin isn't large. The sound stage seems a tad better with the Wiim as well.

Although my setup isn't by any means in the "audiophile" category, I was pleased with it and was aiming for more clarity and better dynamics.

I'm considering three scenarios:
1. Are my expectations for sound improvement unrealistic?
2. Am I doing something wrong, or is my amp/speakers setup limiting the quality?
3. Does the Sony A80J have an exceptionally good internal DAC?

I'd love to hear your thoughts and experiences on this.
Should I consider returning the Wiim and instead invest in an amp with a better preamp and a DAC, like the SMSL SU-1? Since I have the smart TV in the setup and a home server I can create a work around solution for streaming.

Thanks