subs for Sonus Faber Cremona M floor standing

Dear Daveyf: IMHO it is not only the driver dimension/size but which kind and size of magnet, woofer build material, build shape and overall construction and build excecution. In the other side and between other things the amp damping factor count too.

Now, IMHO there are no perfect drivers and one way or the other exist trade-offs and our choice will depend on our targets because if we want " flat " bass frequency down to 18-20hz then a 8" driver can't do it.

Normally when we are asking for a sub we are asking for that low kind of bass.

IMHO low bass is the frequency range more difficult to achieve/reproduce on accurate way and that's why I posted the importance to analyze/research in deep before any choice.

The subs subject and understanding on two channel system is so " new " that even some subs manufacturers has no clear and precise answer about, almost all take the add-on subs mainly as the traditional way: as a bass re-inforcement system but for me and my frist hand experiences with different audio systems is that that " traditional " way of think regarding subs is wrong or at least incomplete way incomplete.
That's why RELs has no high-pass function.

I'm not sure how good are the SF people about but maybe if you ask them how to mate their Cremonas with subs maybe ( maybe not. )they could tell you that the Cremonas in full range fashion and subs as " only " reinforcement bass.

Anyway, the subject is open to questions/answers and obviously IMHO there is no one answer for every single system/room circumstances.

Regards and enjoy the music,
R.

Well just an update, looks like I am picking up a JL F113 this weekend. I realize that I have to start somewhere. I was real close to the Velodyne as per Raul's advice and some research I did. I unfortunately got the JL bug and need to put it to rest. I will post my thoughts as they come. Thanks again for everyone's two cents. Now I see why I was confused on the matter.

12-14-11: Erictye
Well just an update, looks like I am picking up a JL F113 this weekend.

Oooh. I think you're going to be really happy with that. Congratulations.

Well I just set up the sub for about 20 minutes now. I had a DBX drive rack PA kicking around. I had to run some cheaper lines as my Purist are rca only. All I can say at this point is I am definitely getting another sub. This is exactly what I was missing. I need to do a bit of fine tuning yet. I have a question. On my C2300 I have to outputs to go to amps. Can I run the sub amp directly to the second set of outputs thus eliminating the DBX drive rack. What are the pros, cons doing it either way.

12-05-11: Stanwal
... I have found it ALWAYS better to run the speakers full range and only use the subs to augment the very bottom end. True, you don't relieve the amp of some work but on the other hand you are not running the signal through another crossover which will invariably degrade the sound. If you like the sound you now have and just wish to augment the bass I suggest that this is the way to go. If you want to play louder with more boom go the other way.

This is predominantly my experience as well. I have done eight different subwoofer installations, and in most cases (especially for music-only) I get the best sound running the mains full range and leaving them out of an additional crossover, while blending in the sub from the bottom up. The only system where I use a high pass crossover to the main speakers is in my home theater setup. In that case, the crossover is to take the strain off the smaller center and surround speakers, but I still run the L-R floorstanders (Mirage M5si's, good to around 26 Hz) full range. And I get the best overall sound and clarity setting the sub crossover to 40 Hz.

For my current 2-channel music-only system I run Mirage OMD-15s full range and use a pair of Mirage MM8's crossed at 50 Hz to augment the low bass only.

Running the mains full range seems counter-intuitive, but even running them that way I still experience more 3-D imaging--the main musical images pop out into 3-D, and the dynamics are subjectively improved. Again, counter-intuitive, but it works for me.

12-17-11: Erictye
Well I just set up the sub for about 20 minutes now. I had a DBX drive rack PA kicking around. I had to run some cheaper lines as my Purist are rca only. ... I need to do a bit of fine tuning yet. I have a question. On my C2300 I have to outputs to go to amps. Can I run the sub amp directly to the second set of outputs thus eliminating the DBX drive rack. What are the pros, cons doing it either way.

How are you using the DBX Drive Rack PA now in relation to your Cremona Ms and the F113 sub? Are you using it for room correction, as a high pass crossover to the Cremonas, or both? If you're using it for high pass, before you try much else, try running the Cremonas full range, and blend in the F113 from the bottom until you notice it, and then back off until it totally blends. It won't cost you anything and it may make wiring for a second sub much easier.