Another Subwoofer Cable Topic

@carlsbad 

I think you misunderstood.  I am not trying to take one bass signal and split it into two.

The engineer who makes subwoofers see fit to install a Left and Right RCA input.  Why, if the driver is mono? There is no stereo input into the driver.  It's a positive/negative wire.

Again, I have connected a single RCA to just ONE RCA input and got terrible bass output, until I used a splitter to attach to BOTH RCA inputs in the AMP that powers a single subwoofer.

My question is really why does that happen and why do manuals always say to use one when clearly that isn't the best setup for performance.

On my other system, the receiver has a LEFT LFE and a RIGHT LFE mono output.  When dealing with Surround Sound, you can program a separate left and right bass response.

@oldhvymec 

Again, I clearly confused folks or folks aren't reading my entire post.

My questions has nothing to do with LFE.  It was mentioned because I have two different setups and each is connected differently.

One powered sub has two RCA inputs.  White/Red - Left/Right. Manual says, connect only to ONE INPUT, usually the Right/Red. I have discovered this to be wrong and do not understand why they continue with that instruction when you get more volume in your bass by choosing to connect to both RCA inputs.

My question is whether to use single point-to-point connections or use splitters.

@oldhvymec 

Sorry, I am on Prednisone and it makes things a bit cloudy. :(

Columns are something I can aspire to in my main system, but not in the office. It's powered bookshelf speakers with a single powered sub. I wanted to upgrade the cable for the sub, but was trying to figure out if I should use two cables or one cable that is split.  I still don't understand why it has two inputs if you aren't meant to use both.

@carlsbad 

Where is the other signal going? In this configuration, the signal path is being provided by a powered speaker. That speaker has left/right outputs.  They aren't specifically for bass; they're just RCA outputs.  Therefore, they would produce full range.  The speakers are the same manufacturer. So they say just run one RCA down to the sub via one RCA.  However, I am using both.

So, is it that I am doubling down on the same signal and marring bass? Again, why do they put two inputs if you aren't meant to use two?

@erik_squires 

The connection in this case is one shielded/grounded cable out of one of the Receiver's LFE channel to NHT  monoblock amps.  One is the MA-1A and the other is the Sw2p amp. Both behaved the same. Connecting to one RCA,  I had to crank the volume knob to its max to get audible bass, and not very loud. Connecting a splitter in order to use both RCA inputs on the amp resulted in overwhelming volume and the volume, of course, had to be turned way down, to maybe 10 or 11 o'clock to get extremely loud bass.

I haven't had such problems on the office sub, but I also haven't tried.  Although, I did run a test against using just any old RCA interconnect vs using a higher quality interconnect and heard an extreme loss of bass on the ordinary cable. *shrug* That's a different post for a different day. ;)

@erik_squires 

Then why was I not getting reasonable volume until I used both inputs on my main system?

@lordrootman 

Ok, now that I have a baseline on what's going on, what are your thoughts on this idea.

I want to get Synergistic Research's Reference Subwoofer cable. Since it is single RCA end-to-end, and they don't make a Y-Splitter, what if I use that cable on the manufacturer's recommended RCA input, and use the Synergisitic Foundation RCA cable I am currently using on the other RCA input.  That way I am satisfying the voltage but are using the stronger cable for signal? 

@lordrootman 

Wow!  Excellent information!  Thank you!  Now it makes sense. :)

@lordrootman 

Understood. 

I am a believer, and I did do one test on my subwoofer which helped seal the deal for getting better cables for it.  Keep in mind this is purely rhetorical and only impacted this setup, so other people might have a different result.

When I was spec-ing out my subwoofer cable, I was reading up on what was "assumed" made a good subwoofer cable. It seemed the most expensive had a conductor that was a solid core of copper plated in silver.  Well, I just happened to have some old Audioquest Component (R,G,B) cables that had that EXACT same conductor.  A solid copper core plated in silver. At the time I was using some very old Audioquest Ruby X3's on the subwoofer.  I connected the RGB component cables and.....lost almost all my bass. I cranked it to full 250 watts and the bass was still weak and flabby. However, according to most people, it shouldn't matter because a conductor is a conductor and shouldn't limit or stop the signal.  IN other words, it not supposed to be "tuned."

Now, with that said, Component cables are setup to propagate a 75 OHM, high speed video signal and not audio. It was also a single conductor, end-to-end.  The Ruby X3 has three solid copper conductors per cable and was designed to propagate all signals from 20hz to 20Khz.

So, it clearly means that one cannot just connect any RCA ended cable to a subwoofer and expect good bass.

Ergo, I became a believer that it is possible to create a cable through careful conductor choices and geometry choices that would propagate a low frequency signal better than another cable. :)