The Yamaha HS sub doesn't totally suck. It goes down to 32Hz in my room, my graphs are around here somewhere. I think any sub is a good sub if you have no sub. You can always save up in the mean time.
Maybe I'm wrong but, for me, 90% of sub is just levels. Extremely precise transient, or envelope, response, ultra-low distortion, and other qualities don't seem that important to me. I'm a midrange guy, and mono, and I consider sub bass almost a necessary evil.
If you're a bass head then you probably think I'm crazy. I understand because that necessary evil is still necessary.
So you have that Yamaha Sub 8S? It goes around 450euros in Europe. Its pretty "cheap" when comparing to Focal or Neumann subs.
Maybe I'm thinking that I want a really good quality sub, to fully integrate into my system. Basically I would have it on all the time, to only operate below 50hz. Extend to the lowest lows, and feel the bass more.
My twins already go down to 40hz, in my measurements, maybe 37hz. But I really can't feel the bass. (Unless cranking volume, but then its too piercing, I get ear fatigue too easily.)
And yeah I have a single mono avantone mix cube for that sweet "sexy" midrange
I'll just add that there's an argument to be made that THD is less of an issue with subs simply because the limited range of the sub doesn't produce the upper harmonics.
Ya, I was just throwing out variables. I figured there must be SOME reason they charge so much for a speaker in a box. Pasim, I have whatever the first gen one is. Honestly, I never ever crank it that loud to where I feel much bass; maybe a bit in my toes. You can also get a wearable transducer or buttkicker for direct vibratory action.