Subwoofer: should we even use them at all?

Bo1972,

What do tou use as active crossover, and how is your system set up? I'm looking into this right now. Actually posted a new thread on the Tech Talk section.

Shameless tangent!

Marty: I'm interested in your experience with room correction. I also use Rythmiks (two 12" very heavy DIY boxes) in a stereo setup. I'm looking into Dirac for room correction (as my only source is a highly optimized computer), plus an active crossover to high-pass the tube amp and send the bass to the subs. Was wondering what your experience was with active crossovers?

Now, more relevant to the original post: I have small floorstanders (B&W 804S), and adding a sub was a good improvement. I started with a REL Storm III as reinforcement to the low end. Using measurement software/mic and a lot of time, I achieved good integration and I was much happier than without the sub. That REL has one 10" driver.
Then I replaced the REL with two 12" Rythmik subs. Much better! Initially they were also used as reinforcement in the lowest bass. I used Earl Geddes approach: both subs running a summed-up-bass signal, both set up with different crossover pounts, different phase, volume, etc (and different adjustments in the PEQ section) to get a smoother room response. And indeed it was a lot better!

Lately I tried an experiment: high-pass the tube amp (and hence the speakers) thru the crossover built into the plate amp of the Rythmiks, that crosses over at 80 Hz. Subs were kept in the same location (for now), but are now used as stereo and with different settings from before. This gave me a better sound. Better soundstage, imaging. I think the explanation is my speakers, while they can reproduce below 80 Hz, do so with higher distortion. Plus the tube amp must not be too happy to go down there either.
So in my experience subs are a very good thing for music. They do take significant effort and time to get right. And the reasons why they are a good thing aren't only about reaching down deep in the bass, but in some cases relieving the amp and speaker from playing where they are not most comfortable doing.

Cheers!

Marty,

Thanks for the answer. Was wondering how is your signal chain configured? From server, do you go out through USB? Straight into the Onkyo? Then the Onkyo does the crossing over, the room correction, and where is the DAC performed?

I asked the miniDSP folks about suggestions involving Dirac Live and crossovers. One option they suggested was Dirac at the server and their nanoDIGI 2x8 for a crossover in the digital domain, but also a second DAC dedicated to the subwoofers. The additional DAC I'm trying to digest...I guess any timing differences between the different DACs used would be compensated by the room correction...still not easy to digest. And I also wonder about additional jitter in the chain.

What are your thoughts on this configuration?

Marty,

I certainly agree with you on simplicity being preferable. Further looking into these units I came across the DEQX HDP-4, and the QOL, amongst others, but these appear to be most endorsed. What's your thought on these, as an experienced DRC user?

I think the approach proposed by miniDSP is a non starter for me. As much as I love my Lamm pre, I think I will need to decide if I'd rather keep it or do the mains/sub crossover and integration thing. Much to consider!

Marty,

You are right: after further reading about the QOL, I realized it doesn't do what I need. So that one's out.

Switching cables between the Lamm and an Onkyo doesn't sound like me. I'd rather spend the time I have for listening to music just listening to music rather than swapping cables. We are likely alike along these lines.

About the Lamm: this is not their reference preamp; it's their entry pre, in Lamm terms. So it's not a huge investment compared to the other components, and is similar to the ARC and Joule pres you replaced with the Onkyo+Audyssey. BTW, at the time I was looking for a pre I did consider that Joule pre.
The problem is I cannot listen to any of these options beforehand, so it comes down to a leap of faith.

But the two Rythmik subs I already have and I'm sold on using them.

I'm also ditching the path proposed by miniDSP. Too complex to implement and cumbersome to operate, especially the latter.

So it looks like I need a DEQX, or Onkyo 5509, or HK 990 to replace my DAC and pre, and using Dirac or another DRC software at the server, and call it a day. I can't see other practical alternatives as of now.
I might start with the DRC software and a cheap crossover between pre and amp, knowing it's a temporary setup, and finally settle on replacing the DAC and pre with a digital processor.