Originally Posted by rcohen
They are clean and articulate. They make it sound like your mains got great bass, rather than drawing attention to themselves. They aren't power monsters, but the pricing is good enough that you buy more to make up for it, and I'd rather have more subs for room modes and better seat to seat consistency. I have a 6000 cu. ft. room, so I have demanding power needs.
I was able to compare them to FV15HPs, and I much preferred the F25s for music. I also preferred the F25s for movies, but by a smaller margin. In both cases, the F25s had more detail in the bottom couple octaves and had less localization, although the FV15HPs could produce more output per sub.
For the difference in detail in movies, one particularly clear example was in Incredibles on the island, when the killer robot was rolling around chasing Mr. Incredible, bouncing around the ground and smashing through trees. With FV15HPs, it sounded like Rumble! BOOOM! BOOOOM! And impressive sound effect. With the F25s, it was like you were really standing there, able to feel every subtle interaction between the robot and the ground in detail, not a sound effect.
With music, the F25 sounded more like real bass drums, and less like subs.
These differences were mainly below 40hz. Above that, they sounded extremely similar. Above the bottom octaves, the only way I'd be able to tell in a blind test was that the FV15HPs were easier to localize when using a crossover over 80hz. Mine are currently crossed at 100hz, so this was an issue for me. Compared to my previous Velodyne sub, I am impressed with the Rythmik subs' abilities to handle higher frequencies.
To really get drums sounding lifelike, I found that combining with high efficiency mains (running JTRs) and fine tuning frequency and impulse response with Dirac also contribute a lot. After all, drums aren't just in the subwoofer frequencies, and typical tweeters simply can't reproduce lifelike transients.
Once I used Dirac to fine tune the response, I was able to find a single setting that worked very well for most movies and music. I struggled with that when I was trying to dial in the response by just tuning the crossover and sub gain.
Also, I was much happier with the results when I corner loaded (4 corners) and used EQ, instead of going with sub placement that produced the flattest natural response (front and back center wall). As long as there are no nulls, Dirac and XT32 each did a fine job managing peaks (although I prefer Dirac, especially for full-range EQ). With center wall placement, I found that I was sacrificing too much output to produce truly satisfying bass in my room.
I agree with you 100%. The F25 does not sound like a "sub" at all, in fact it is completely invisible. It seemed as if my main speakers had grown a large pair of balls.
I was wondering about the F25 vs the FV15HP, so I'm glad you heard both and answered that question in my mind.
The first time I powered it up I had to keep checking to see if it was running at all.
My single F25 seems a little light for my room, particularly for movies so I'm getting a second next week.