Curious what other people have in their systems that’s a total sleeper. Mine would have to be a pair of Pioneer S-Z9. They were released circa 2008 bundled with a pioneer network integrated amp. Original MSRP was $1800 USD for the system. I ended up buying these off Canuck audio Mart new old stock (sealed in the original boxes) for $200 Canadian shipped.
They actually were a collaboration with kef, with the drivers originally starting off as 7th Gen UniQ drivers but use TAD (also owned by pioneer) carbon/Plastic/ injection molded matrix cones (3 layer) to improve cone stiffness and dampening, Instead of the molded ridges kef uses on there poly drivers. They are pioneer cast aluminum baskets as well. Crossover also appears to use high quality brands on the caps.
They are very well built, piano gloss finish, 21 pounds, and have a frequency response of 36hz-50khz!! Seriously I have never heard bookshelf speakers this size that go so low!
They are 4ohm and only rated for 50 watts RMS but I’ve been using them at my computer with a bel canto s300i (300 watts RMS into 4ohms) and they sing!
The design is based on the notorious YouTube video by Tech Ingredients “World’s Best Speakers”. I wasn’t expecting much, but just for the entertainment value, I made a pair. I was frankly astonished how they sounded. I dragged friends and neighbors over and forced them all to listen. They claimed to be impressed, or were just humoring me 😊.
The DML panel size I used 24x24 inches is not full range so they need a subwoofer. But with that, they are simply uncanny at producing (simulating?) a live music experience. I made a couple more versions trying to figure out how to support them and protect the XPS panel from damage. My final version has a frame similar to a picture frame, and a back panel cut into an open honeycomb. The panel mounting is steel cotter keys epoxied into the back of the panel in three places. Those attach to the frame using high tension monofilament fishing line that acts like a spring suspending the panel. The panel floats in the frame. I used two 4 ohm exciters wired in series to achieve 8 ohms. The frame then is mounted to an articulated flat-screen TV arm so that the speakers can be pushed up against the wall or pulled out into the room as much as 24”. They sound best out from the wall.
They are very efficient and can be driven to high volume with very little power. I’ve used them with a cheap Chinese class D, a SUT tube amp (1.5W), an ACA kit amp, and my current favorite amp, a Hypex Nilai 500DIY, which rocks 260W in to 8 ohms (an awesome amp BTW).
There are a couple of unique characteristics of the speakers, one is fantastic sound stage and imaging regardless of what’s driving them. Even the shittiest little class D throws a huge sound stage. The speakers are almost completely transparent, with no sense of the sound coming from them until you get within about a foot or two. The listening position is very broad, with decent imaging even way off axis. Likewise, speaker positioning is also very forgiving. They have excellent dynamics and as I mentioned earlier create a real sense of a live performance.