This will probably date me and make me sound like a total noob, but I've got an old Pioneer VSX-5300 AV receiver with no dedicated sub output. It's got two main speaker outs, two rear outs, and a center out. These were made back in the late 80s, which I guess was before subs became popular. Anyway, the unit runs fine, and although I will eventually replace it, I'd like to keep using it for the time being if I can figure out how to use it with a good quality sub. After perusing this forum and a couple of others, I'm under the impression that some subs support running the main speaker outputs into the sub and utilizing the crossover, and then running separate wires from the sub to the speakers. If anyone can confirm or deny that, I'd greatly appreciate it.
Assuming the above scheme is doable, I've narrowed my sub options down to the Emotiva X-Ref 12 and the SVS SB12-NSD. Looking at the back panel pics of the Emotiva, I'm not sure it supports the wiring scheme mentioned above, but the SVS model possibly does. Anyone know for sure about either of those models? Thanks in advance.
Replying to my own post... after emailing SVS and Emotiva about the compatibility of my receiver with their subs, the verdict is that their subs do not have "speaker level inputs", which is what is needed for my receiver to be useable with a sub. So, I'm now looking at upgrading to a receiver with a dedicated sub output and I found the Outlaw Audio RR2150, however am now trying to figure out a new mystery. The 2150 has a single "Sub out" RCA jack, which can be seen here: http://www.outlawaudio.com/images/2150R_Huge.jpg The mystery arises when looking at the back panels of the two subs previously mentioned. Both have dual left/right RCA inputs. So, the question is, what's the proper way to connect these units? Run a single wire from the sub out on the receiver into the left channel input on the sub? Or something else? Guess I will email Outlaw next...
Outlaw often times uses Hsu subs and relabels them as their own. Either way, Outlaw or Hsu, they are very high quality products for the money spent.
You have the option with most subs of running either a line level or a speaker level input. Some listeners prefer the sound of one input vs the other. Otherwise, run a single line level cable to one of the input jacks on the sub and that should make all the connection required to make the subwoofer operational.
Bass content is mixed into mono and only one line level out cable will be needed. Typically, the output jack on the receiver/processor will be labeled either "sub out" or "LFE out" (low frequency effects). In either case, after you've made your line level connection, you should then be able to set a crossover "knee" frequency (where the crossover begins to take effect and the action of the filter would begin to show a roll off) at the receiver/processor through the main set up menu of that device. This willl place an active (electronic) filter in line with the sub output which will determine the (low pass/high pass frequency) crossover point for the system. Begin your system set up by placing the filter (frequency point) as low as possible and slowly raising it as you listen to a variety of material until you are satisfied you have a good blend between the main/center speakers and the sub with no holes or excesssive overlap of content.
The crossover filter on the sub will be set to its highest frequency in order to avoid any overlap of filters. So, if the sub has a variable control for the crossover between, say, 40 and 180Hz, you would set the filter on the sub to 180Hz and make all corrections through the receiver/processsor's menu.
You will need to determine which input is mono on the sub, left or right, and make the connenction to the appropriate jack. This information should be provided in the subwoofer's owner's manual. Making your connection to either side is OK but one side is typically set up to be the most efficient connection point. Should the receiver/processor provide two output jacks (L+R), you still only need one line to the sub since the information being sent is strictly mono. Running a second line or splitting a single line into two outputs by using a "Y" connector at the sub will raise the gain of the subwoofer's (plate) amp by a few dB. Raising the gain of the system is equivalent to lowering the input sentivitity of the system (in effect making it "more sensitive") in that you will not be required to raise the level control quite as high to obtain the same acoustic output level. No more power is available beyond what the amp can provide so, raising the gain of the system doesn't accomplish anything other than in those rare cases where very high sensitivity main/center speakers are paired with a relatively low sensitivity sub.
Bottom line, one line level input is all that's required to make the mono low frequency information work with any powered sub. If you prefer the speaker level connection for sound quality reasons, then you'll need both left and right lines run to the sub.
Thanks, Jan. I think I have just about enough info now to pull the trigger on the RR2150 and probably the Emotiva X-Ref 12. Looking forward to hearing the improvement in my system.
My HSU sub has a crossover in/out switch. Per Jan's instructions, this switch should be set to 'out' so the receivers crossover is used.
Be ready to spend some time with sub adjustments. I recently made a small adjustment which was a large help in the sound. Some HSU subs have 2 ports. The sub comes with a port plug so you can run the sub either of 2 ways. I found the 2 port open option to be the most.....musical, without messing with movie performance. Also, where the sub 'looks' best may not be where is sounds best. HSU, for example, usually recommends a very close sub placement to the listener. This helps do away with many room effects which can plague someone trying for a good setup.
Thanks, Leo. The Emotiva X-Ref has several adustment controls in addition to the crossover setting on the RR2150, so yep, I am looking forward to fiddling with it and getting it just right for my listening room. The room is small (11' x 13' with an open 3' x 7' closet on one end) so the sub will be fairly close wherever I place it. I am hoping it sounds good in one of the back corners to either side of my loveseat/couch as that would be the most convenient spot, but we shall see.
Be careful running crossover controls in the amp AND at the sub.
Now, you have another decision coming up. Will you run your main speakers full-range or restrict bass to them? You can use the subs crossover and continue to run your main speakers full range. The idea would be to allow the sub to pick up as the mains leave off. This is what I do. Plan 'b' is to more aggressively cut the mains off as the sub comes in range. This has the advantage of helping your main amp out by keeping it from reproducing the power hungry bass end of the spectrum. Maybe use the sub as an end table?
Yep, that's why I ordered the RR2150, so I could use the crossover it has and send the bass freqs only to the sub, thereby saving some wear and tear on my mains. They are the Focal 807v's, which only have a 7" woofer and get down to only about 47 hz or thereabouts. Figure I will set the RR2150 crossover at 80 hz to start with and see how it sounds.