I feel like the only person with this issue... Receiver w/ wire out to old Sub

[SkyHighGam3r]

I have a Sony 5.1 audio receiver (I don't have the model# handy)

This receiver has ONLY Speaker wire outs for the Left/Right, Center, Rear Left/Right AND Speaker wire outs for the Sub-woofer. (NO RCA)

As you can surely imagine, the sub-woofer than came with this system is pretty much garbage. So, I have a fairly nice active sub-woofer from at least the 90's that I will be using.

The issue I run into is that this Sub-woofer has L/R RCA input jacks, and 8 speaker wire in/out terminals.

That's like:

L | R
Input - + | - +
Out - + | - +

L / R
Input o o << Red/white


Currently, I have 2 wires that are one end speaker wire, and the other end RCA going from the receiver's speaker wire out terminals of the Front Left/Right speakers, and then into the RCA inputs on the Sub.

(These are intertwined with the Front L/R Positive and Negative wires for the actual speakers, i.e. I have both wires for the sub and speakers going into the same terminal.)

The problem I find is that the sub-woofer will very distinctively only kick in once the sound has passed some kind of (What I can only call) Low sound level threshold...

That is to say, once the bass in the show/game I am watching/playing goes low enough it kicks in like a rocket.

I have tried playing with the crossover frequency dial a bit, (I don't really understand it's purpose to be honest) and I don't see much difference in this effect.

After doing some research, I understand now that there is a difference between high/low level inputs/outputs for these things... and I was thinking I might try some other crazy wire conversions on it.

i.e. +/- Subwoofer speaker wire out, to a wire that is RCA on the other end, y-split that to 2 RCAs and then into the RCA jacks...

or should I just forego this crazy nonsense and plug the a/v receivers left/right speaker wire into the subwoofer, and then the left/right speakers right into the sub itself?

Or should I figure out a way to connect both the speaker wires/speakers AND the L/R to the receiver?

Any help would GREATLY be appreciated, I'm a techy guy, but this particular issue is a little complex.

 

[Dogsnake]

Easy. To use your subW. connect the receiver subW. (speaker wire type outputs) to the subW. L/R speaker wire inputs. Done. The subW. speaker wire outputs would be used is a 2 chn. stereo system with a single amp to connect the monitors. The subW. has a crossover network built in that would then pass all but the bass frequencies to the L/R monitors. Since you have a 5.1 receiver the channel splitting is done at the receiver and the output sent to the speakers. The RCA connections would be used if you ran your Preamp output to the SubW. and then used the SubW. crossover and speaker wire outputs to the monitors. The reason there is a delay in you current hookup is that there is a relay in the self powered subW. that turns the sub amp on when it detects input signal. When no signal is present it goes into a standby mode. Forego the crazy...YES. For your system use the speaker wire connections making discrete connection to each speaker. Each speaker uses a +/- (ie. red=+ and black=-). Do not mix these up. So from the receive you have Left and Right full range speakers, Center speaker and SubW. If you need clarification get back pls.

 

[boosted1g]

I don't know where you got speaker to RCA type cables (im going to guess ebay) but that is completely wrong. You would need a line level converter to convert the signal properly. Now your sub has this built in at the speaker terminals so there is no need to buy a separate box.
This bad cabling + the crossover settings is the two causes for your issue.

Now there is what is called banana plugs that some people confuse as RCA. RCA has an inside male prong, and a outside ring lip, banana plugs are just the male prong.

What you need to do is connect the left/right speaker form receiver to sub in, then out from the sub to the speakers.

If receiver has a large/small speaker setting for front speakers then make them large.
If the receiver does not have that setting then you need to set the crossover on the receiver to as low as it can go.
You can then adjust the crossover to 60-80 hz for the sub.
Your sub crossover is not doing much at the moment because the receiver is already limiting what frequency range is being outputted through the left and right channels.

The purpose of the crossover is to tell it the frequency threshold for the sub to kick it. For the most part you want 60-80 hz like I said earlier.


ADDED:
FYI, if you decide to upgrade, Yamaha's RX-V377 receiver which has LFE out (the RCA plug) to sub is going for $200. This receiver sounds like a nice step up from your current receiver, and Yamaha beats Sony every day of the week.

 

[jitpublisher]

Its been a long, long time since I messed with stereo equipment, but what are ohm outputs of your stereo, and ohms rating on the woofer? If your amp is underpowered in relation to speaker, this could be the problem, and if it is the problem, the speaker can fry your amp. Be sure to check that out.

 

[SkyHighGam3r]

Well, I did a couple things here...

Thank you to boosted1g for the Hz range, and the crossover information that does help with the practical usage end.

So what I did is connected the receiver's L/R speaker wire inputs directly to the sub, and the sub directly to the L/R speakers. (Unfortunately I do not have a speaker size setting in my receiver It's a cheapy one, I know.) As boosted1g sugguested.

Now that worked OK, I got some bass, but not really the Room shaking power this thing has been known to produce (It's an Onkyo, if anyone cares, I hear they are usually good, and I know I've made this one shake pictures off my wall in the past)

So, I took that Speaker Wire to RCA Cable (It's for sure RCA, I do know the difference but I also know what you mean when you say they get mixed up a lot) I took that cable, and put the wire end into the receiver's subwoofer out terminal, intertwined with the original subwoofer's wires.

I then split the RCA end of that wire to 2 RCAs and popped them into the L/R RCA inputs on the Subwoofer itself.

So what I created, other than a monster lol, Is a situation where I have the L/R Speakers routed through the sub, and then the actual subwoofer out on the receiver (speaker wire, converted to 2 rca) into the Sub as well. (Also, keeping the original subwoofer hooked up with it all 'cause... why not)

With this setup I get an IMMENSELY powerful bass output. I watched a trailer for a sci-fi game and when the gun in it fired it's lasers... WOW I got goosebumps.

I also wanted to point out that I got the Speaker Wire to RCA cable at my local radioshack. I know it's a wonky conversion lol, but it gets the job done for cheap and I'm no audiophile. I just want want the THWOOM when things explode in my video games.

jtpublisher, I honestly am not sure what you mean by ohm output... I know vaguely that term relates to the signal (Power level of signal?) But to be honest, all of this is going through a cheap 200$ home theater in-a-box solution I got from wal-mart 7-ish years ago. I am not that tech savvy on the matter, I just want the BOOM and RUMBLE for my video games.

Lastly, I hadn't considered your solution dogsnake, simply because I only have one +/- output for the sub on my receiver, and the sub has a full input for L/R (+/- & +/-) and I'm not aware of a method for splitting speaker wire signals. However I will keep it in mind should I ever find a solution to that roadblock.

Though to be honest, with the power this thing is giving me now only turned up 1/6 of the way... I don't foresee ever changing it lol

I wanna thank you guys for your help and suggestions, this is the first time I've used this site and you all were helpful. I gotta give the solution to boosted1g for the initial direction and the crossover info.

 

[Dogsnake]

The reason the receiver has only one sub out is because it internally sums the left right bass information. Bass frequencies are perceived as "non-directional" 5.1 systems provide for a single bass source point. The two inputs on the sub are for when it is used with a 2chn system. You can attach your single sub speaker receiver out to either one. BTW I use a pair of M/K subs in a 2chn audiophile stereo system. I am an old rocker. There are some notable exceptions to the non-directional bass adaptation used in most sub-woofer systems. The Grateful Dead and others used true stereo bass in concert and in many recordings. Using a single bass source is easier as there are no phasing issues and timing issues for the monitors.

 

[SkyHighGam3r]

I never even considered the concept of 2-channel bass... That's actually quite interesting. I will have to remember that if I ever upgrade to a proper A/V receiver instead of a home-theater in-a-box solution.

I'm guessing most video games just have the 1 channel though, so I should be ok.

Either way, it's good to know I don't have to indulge the bit of OCD I have with these things to connect every port to something somewhere.