Subwoofer connection

[Greg58]

Hello,
I have an older subwoofer that requires both left and right RCA a jack plusgs. However my new 7.2 AV Receir has dual single RCA jack outputs. Can I use a single female RCA input / dual male RCS output connector on the older subwoofer, and will it function properly?

 

[soundguruman]

yes, use a Y cord

 

[CompTIA_Rep]

I don't believe you need a Y cable. The receiver outputs in in stereo and the subwoofer couldn't care less if both channels are received in the left or right channel only.

 

[anwaypasible]

I don't believe you need a Y cable. The receiver outputs in in stereo and the subwoofer couldn't care less if both channels are received in the left or right channel only.

without testing the electrical circuit of the subwoofer, its hit or miss as to whether the amplifier (or subwoofer) could/couldnt care less if both channels are used.
using only one input might cause a piece on the circuit board to fail (or the entire circuit as a whole)
the same can be said for using both input jacks.
its a design, and designs have intentions.
while one method sounds better, the other way might make the amplifier last longer.
are manufacturers supposed to be doing things this way?
well.. if it performed good and one day broke, would you buy another one of the same thing?
if the amplifier broke early, would you be happy with the result when it did work? and would you buy another one thinking 'maybe that one was defective' ?

companies dont have to care about the people who buy their products.
some would say 'as long as it works when i bring it home'
and
others would say 'as long as they built this broken piece of hardware, that means they are a company of some kind of respect'

this thread boils down to how much the person cares about the subwoofer/amplifier.
if you are worried about the piece of hardware breaking, have it inspected by an electronic shop.
they will tell you what is safe and what isnt, as they can be held accountable for bad advice.
the truth, using one input might make the thing break in 5 years.
the same can be said for using both inputs.
and either one of those methods might help the piece of hardware last for longer.

its an issue of trust, and for that you need honesty.
if i was to tell you, this method sounds better but will cause the thing to break faster.. i would then say it is totally up to you as to which method you choose.
maybe i would tell you how much it would cost to have it repaired when it does break.
but that is meaningful advice for all aspects.


do they make Y cables.. yes
can you find some with two male and one female plugs.. yes
you can also find 'em with two female and one male plug.

if i were you, i would check to see if the output of the receiver is actually stereo.. because if it isnt, you might be able to hookup both inputs into the subwoofer amplifier and get a stronger/cleaner signal.
but again, you would have to learn the circuit of the subwoofer amplifier ... and you would also have to learn the circuit of the receiver to know if one or two subwoofer's connected is the better choice (and if there is a better choice)


i think its the same thing when you ask a person working at a restaurant 'what ingrediants do they put in this food?'
that person probably doesnt know.
some stuff comes with salt and pepper already on it.
besides, chemistry is used before the food is sent to the restaurant.. and you would have to ask a chemist what is inside the food (totally different than what is on top of the food)

not knowing how to repair electronics means you dont know what is safe.. it's all a gamble and the only way to avoid it is to buy an extended warranty or bring the piece of hardware to an electronics repair shop.
kinda like owning a car, but you dont have the license to operate it safely.
sure.. you might be able to drive around in an empty parking lot, but that doesnt mean you can control the car when side by side with another car going the same direction at the same speed.


if you dont care to bring the hardware to an electronics repair person, that means you dont care if the thing is gonna break.
using the Y adaptor shouldnt change the resistance of the cord much.. but using both inputs might cause significant change inside the amplifier.
some people simply do what they want and accept that the manufacturer didnt care enough to prevent failure.
new subwoofers have two options, one for left/right input .. and another mono input for the LFE channel from the receiver.
and
some have a drawing right there next to the input to tell you 'when using only one input.. use this one'
if there is no instructions, that does not mean either one is okay.
but that doesnt mean its gonna break the moment you hook it up to the receiver.. its not dangerous like that.
its about numbers in this area 0.000x
and its about the piece of hardware breaking in 3 years, 5 years, or 8 years.

i am happy to hear people care about 3, 5, or 8 years.
but i'm disappointed people dont realize that these extremely specific answers to their questions are hard to come across.
and i dont think anybody should make the decision for them when they show signs of concern.


i hope you enjoy your subwoofer

 

[CompTIA_Rep]

I read your reply, but you really didn't go into reasons why. It sounds like your EE, maybe you can be specific into why plugging the LFE output into the R or L input of the subwoofer would be a bad thing?

 

[anwaypasible]

i dont have a degree.. but i have gathered information to possible reasons (perhaps not all possible reasons, but some)

capacitors and resistors are connected with an intention.
if there is something that vacuums or bloats that intention, it could lead to better output
or
it could cause the components to fail earlier than their life expectancy.

speakers in series can give a bloated example.
if the speaker is ment to sound good connected directly to the amp, wiring the speaker in series to another speaker adds a latency, and the principle of moving in and out in an extremely tight fashion becomes dynamic.
the tight grip grows loose, to say the least.

when only one speaker is connected, the process is of moving in and out is straightfoward.
when connected to another speaker in series, each speaker is receiving input that has been manipulated by the characteristics of the voice coil and magnet of the other speaker.
this can happen from the positive input and the negative input.

when the cone is requested to move outwards, there doesnt have to be anything coming from the negative wire.
that means the input goes into the speaker, the signal has touched something that can manipulate the signal, then the second speaker receives the signal.
poorly designed speakers could show complete differences, when and if, the amplifier is using only the positive wire (or only the negative wire) to energize the coil to create movement.

now, i dont have a degree.. meaning i dont know if the most common amplifier is always sending out a signal from both positive and negative - as if to say the polarity from each wire is constant, but changes polarity.
if and when that is true, the input will be different - but seen equally by both speakers.
that will hide the example of one speaker moving completely different than the other speaker.


when capacitors and resistors are combined to integrate into eachother, changing the resistance of the circuit can be enough to change the way those components work together.
if they were connected to function with oscillation, the shape of the wave could change (either by shrinking or bloating) and that change is in fact a change.
the damage or benefit is completely dependant on the component, as it is designed to work in a specific manner.
not all parts are created equal, and some will have a higher tolerance than others.
but pushing something into a 'tolerance' level, compared to running the component at its 'nominal' or 'expected average' level can produce a new result.

the result can vary.
it could be better performance (perhaps underrated components)
it could be worse performance (over rated, or low tolerance components)
adding life or subtracting life based on error or improvement.

one could say (by experimenting and thus having field results) the common component has a high tolerance to fluctuation and change.
but that would only be true for the hardware tested.
since high tolerance is desireable when it is wanted in the total design of the hardware, it can cause the component to be more expensive.
on the other hand,
lower tolerance can be directly related to superior performance when the design is within specifications of the intended purpose.


i think electronics repair people are like a kid in a candy store. they have lots of options and possibilities.
for instance, if you take a piece off a circuit board and use it in a way that isnt intended.. the performance of the piece might be substantially higher.
the lifespan of the piece would probably be shortened, but for the time it is working.. the improvement would be substantial.

that is the reason why pieces of electronics are built and perform much better than their competition (or perform the exact same, but with a lower cost to build and a shorter lifespan)

its the designers choice to stretch the limits of the pieces, or to under rate the pieces to prevent failure.

i'm talking like this for two reasons:
1. to inspire people to know how to take better care of their electronics, by having someone investige and become certain what method produces the best result - and/or what method produces the longest lifespan.
2. this information can provoke people to wanting to go to school for electrical repair.

learning what makes the piece of hardware live longer or perform better (or both)
is only half of the fun.
when you take it in to the electrical repair person, if they know how to determine what is best.. they should also know how to upgrade the piece of hardware (or if upgrading the circuit board is a cost effective choice)

i'm not saying its possible.. but giving an example:
wouldnt it be nice to bring in your new flat panel television to the electrical person to learn what inputs are the best to use?
and what if the electrical person could upgrade the circuit board to bring the refresh rate of 5ms down to 2ms ??!
that would improve the piece of electronic hardware and make the person happy.
it would also make the industry happy, because they are there to entertain people.
for them to entertain, people at home need to have functioning equipment.
it boils down to a better experience when you turn on the television to be entertained.
and if people can save some money by having their electrical person upgrade something.. that brings more business to the electrical person (more money for them) and it will also inspire the owner of the television to rent more movies to play with their new toy.

i like how a 'toy' can be transformed into something 'serious' without having to spend $1,000 extra dollars.
sure, maybe the upgrade costs $500
but
the $500 you save could go to renting movies or paying your cable/satellite bill
or
you could take the money and add to your home theater experience.

the manufacturer's of the television arent necessarily wrong when they build something and sell it to people.
but if somebody can improve the hardware, an improvement is just that - an improvement.

 

[Greg58]

Thanks for the advice, everyone. I did ultimately end up buying a Y Cord, and the old subwoofer works great. However....after reading anwaypasible's response, I may just go ahead an invest in a newer, more technically advanced subwoofer with a single RCA input. A smaller expenditure now makes more sense than burning up the subwoofer and/or the amp. Thanks again!