Dream Speakers = landed. Now I need to feed them!

I can’t make suggestions on a source/DAC but can relate my story with the Belles and make a few observations on amplification that may be helpful. From my experience (and with my taste in music) the Belle’s need a boost at the bottom end which was suggested above by @tds3371. For the first 20 years of Belle ownership, I achieved this with preamp EQ…..for the past 15 years I have used either EQ or a sub. With your tastes in music, you may not feel this is necessary. Are you using your Sony’s tone controls or loudness feature to get your current ‘great’ sound?

I bought the Belle’s new in 1984 along with a Mac C33 preamp. The C33 has a 5 band EQ + Fletcher Munson variable loudness dial. With these controls I could shape the music around various rooms and types of music and really push deep, loud, driving bass from the Belles 15” woofer. During this early ownership period power amps included 50 and 200 wpc Brystons (ss), 105 wpc Mac (ss), 140 wpc B&K (ss) and a 35 wpc Cary (tube).   The latter tube amp was by far the best sounding with the Belle’s.  EL 34 tubes for sweet mids rolled to 6550s for more bass punch.   In 2005 I purchased a 1000-watt SVS ported sub with two 12” drivers for a 5.1 system (Belles up front and 2 pairs of Heresy’s in the back and center). This was driven by Bryston 4Bs and 3 sets of Bryston 2Bs and controlled with a Mac AV preamp.  Very exciting/dynamic set-up for movies and concert videos.

Once my kids were out of the house, I disassembled the 5.1 and focused on stereo with the Belles and SVS. I wanted to see what the Belles would sound like with a tone control-less preamp so I purchased a PrimaLuna Dialogue…..this is where I rediscovered that the Belles needed help at the bottom end to sound balanced. For me, the SVS was a perfect match for a 2.1 system.   Within the past 2 years I have purchased a Cary 300B integrated amp (15 wpc) (like you I always heard 300B were great with Klipsch Legacy) and a First Watt SIT-3 ss amp (18 wpc). Both sound sublime with the Belles (and with Heresy’s and Zu DWs). I laugh to think I was driving them with such high-powered amps in the early days – I was young and thought more power was better :-).   I can still sound shape with the C33 but mostly use the PL tube preamp with SIT-3 or the CAD 300, both with the SVS sub in the mix.

Btw, I did upgrade the crossover and tweeters 3 years ago with the Bob Crites A/4500 xo and CT 120 tweeter.   This pushed the midrange xo point down from 6000 to 4500 hz so the tweeter is now covering down to 4500 hz. In my opinion, the top end became more forward (not bright but more present) then with the OEM set-up which is good for most music. Listening to "Jazz at the Pawn Shop” the noise floor is very low and the tinkling of every ice cube in every glass is magical. The perception is that you are sitting at a table in the night club.

Good luck with your journey!

Whatever you choose to power them optimizing the internals of the speakers will increase the apparent sound quality by as much a 50%. Putting in the best polypropylene capacitors (top Wimas are recommended) & Vishay resistors will do wonders. Better audiophile wire as well. Klipsch in the 70s put monster cable in their production speakers which meant it was Paul Klipsch's idea. Don't know how that progressed but it clearly points the way. You may need to double up on caps for their values to match what's in the xover. That might mean an exterior box. One thing's for sure, you'll be near staggered by the difference in sound quality.