A "How To" question on Sunfire SDS 12 set up. Any advice welcome.

Hey All, long time lurker and I love the site.

My question involves the subwoofer set up options for my Sunfire SDS-12 subwoofer especially as it relates to my Frankensteinium system.

Details: my Media Room is 20'x20'x13' (it has avaulted ceiling), with "the system" on one side 2 feet away from the wall, speakers are 10' apart & my couch is about 16 feet away. The sub is in the lefthand corner a foot away from each wall facing directly FORWARD.

The system...and here is where it becomes really tricky...vintage & working perfectly 1993 B&K Sonata Pro-10MC preamp & matching 1993 B&K Sonata ST-202+ amplifier, a 2008 pair of Monitor Audio Gold RS8 speakers, the subwoofer in question and trickiest part...the signal source is an OPPO Digital BDP-105 3D blu-ray player that is used for both HT & music (primarily Zeppelin, Yes, Pink Floyd but also 'classic EDM' like Orbital, Underworld,the Chemical Brothers, etc.

So those are the details. Now we know one of the big differences between the SDS and the HRS series is the lack of a directly capable speaker connection on the SDS. I have line-in & LFE RCA jacks that run straight from the preamp. There are also 2 RCA jack line-outs that I am not sure of. I mean, I am not sure what they do. So, on the preamp which has 2 preamp out RCA jacks, one set runs to the amp &the other to the sub. Clouding the issue is the OPPO itself allows you some limited but important tools (like setting the crossover frequency) that cold alter the sound at source.

Now, the real 'problem'. The whole thing sounds GREAT. I really cannot complain. But...I have always been cloudy on proper true subwoofer set up and with the mixture of 90', 2000's, and 2010+ gear, my view may be further clouded. My question is, even though I think it sounds great right now, is there something I have missed that could improve it further? My thanks to any who feel like answering.

The way you have it hooked up now, you are running your speakers full range. If go from the preamp into the line in on the sub then out from the line out on the sub to the inputs to the amp then you will be using the high pass filter option that the sub has.You can give it a try and see what sounds better!
Age doesn't matter. Connections don't matter. All that matters is finding locations and settings that allow the subs to reinforce and extend bass response smoothly. 

The more subs you have the easier this becomes, which is why the best method is a Swarm or distributed bass array approach with 4 subs. But if you are happy with what you have then great. That's all that matters.

Btw one reason you may be happy is that you're running your mains full range. Running them full range is in effect giving you three bass locations. Three is a lot better than one, which is what you will have if you follow the traditional and misleading old school advice and put a crossover and/or equalizer on your mains. 

To answer your final question the main thing that will improve it a lot more from here is the addition of a few more subs. These can be more of what you have, or bigger/better, or smaller/cheaper. Which subs you use or even their quality to a certain extent or surprisingly even their location is much less a factor than the number of subs you use.

This runs counter to the majority of the conventional wisdom you will hear. So if you seriously want to improve your system sound in a way that will not in the least affect the midrange and up but will stupendously improve low bass while creating a feeling of immersion you never dreamed possible then you might want to do a search and read up on the Swarm, distributed bass array, and look for posts by me and Tim aka noble100 and especially Duke aka audiokinesis.

Thank you both for replying and I am sorry it took so long to get back to you. Just so that I am clear, yougiboy, you want me to run preamp OUT straight to the sub (by passing the actual amplifier altogether, then using the output jack on the sub and running that output to the amp? Have I got that correct? If you are still reading, let me know just in case I don't blow something up.

And, as for the Swarm, I confess...never heard of it but that doesn't mean much. I am an old, worn out audiophile who's attended almost 300 live concerts in my life and since I seem to have had a tendency to stand to the left side of stages, I can no longer hear anything at all above 5K in my left ear. The music, tone, whatever is used just vanishes. My ears combined can still hear okay up to about 13.5K...above that, everything vanishes. So, if you have some URL's you can show me about the Swarm system, I would love to have a look.

Thank you both for taking the time to answer a question from a lurker and then waiting for 4 weeks to get a reply.


Yes that is the correct way to hook up a sub using the high pass filter! You can try it both ways and see which way you like best. Some prefer running full range. I prefer using a high pass filter with the sub and the speakers that I use! It all depends on blending the sub with the mains that will give you the best results!