Wiring Subwoofer for 2-Channel

[bwanac]

The age old question.

I bought a new amplifier. Previsouly I had my subwoofer connect to the Subwoofer Out on my receiver. This new amp does not feature this. Now I know there may be a couple options to wiring it onto this amp.

Gear: Rotel ra 985bx
platinum audio pt801
sony sa wm40

So this is my dilemna. Right now I just have the platinums connected to the Speaker A on the Rotel. Sounds great! Now, can I wire the Sony to the Speaker B and then turn the selection to Speaker A+B? Or is that no good?

The other option is the trusted running the signal through the subs high-level speaker inputs and then to the mains. However, since the Sony is not the greatest of sub, will I lose much clarity running through it? Or will signal degradation be minimal?

I would love to keep the Platinums directly wired to the Rotel and wire the sub up seperaratly, but Im thinking this is not really an option. Help!

[PeruvianSkies]

What exactly is your goal? Do you feel that you need the sub?

[bwanac]

Yes... the bookshelves lack a lot of range. Well... probably from 60-down. A little help is always nice.

[Grandpaw]

Welcome to the forum! My friend had this same question when he wanted to hook up a SVS sub he wanted to purchase for his two channel system. The answer we received back for the preferred method was written out but I made a picture for my friend so he could see how to do it. If you have the same type of setup on your amp try this. It works great for him, Jeff

This is what was recommended for us from SVS.
"The first method and the one that we recommend is to run RCA cables from the left and right PRE OUT 1 outputs of the C370 to the left and right inputs on the SB12-Plus and then run RCA cables from the SB12-Plus outputs to the left and right MAIN IN inputs on the C370. With this connection method the SB12-Plus will be playing the bass and removing the information below 80hz from the signal sent to the main speakers (allowing them to play the rest of the frequency range more effortlessly). "

[bwanac]

Yes... something like this crossed my mind earlier, however the Sony sub only has one RCA for in and one for out. Therefore I figured I would lose the stereo signal, and I would much rather have stereo than mono.

I think I am left with the method of wiring them in parallel. Ill just have to try it out.

Do I run any risk wiring subwoofer to Speaker B and Mains to Speaker A? (Just so I can try it)

[bwanac]

Ok... I am confusing myself.

Right now I have the mains wired to Speaker A. I wired the subwoofer in via Speaker B.

If I select Speaker A, I get sound only from the mains.
If I select Speaker B, I get sound only from the subwoofer.
If I select Speaker A+B, I get sound from the mains and the subwoofer.

So is it ok to run it this way. I assume this means Speaker A and Speaker B are wired in parallel when I select Speaker A+B. Or do I have it backwards?

[bwanac]

Any problem running the mains and the subwoofer from the same binding posts?

[Grandpaw]

Any problem running the mains and the subwoofer from the same binding posts?

I looked it up in your manual and this is the way it said to hook it up. I made the diagram for you,

What you do is hook speaker A, left and right out from the Rotel to the speaker left and right in on the sub.

Then you go from the left and right out on the sub to your main speakers. This is how the sub manual says to hook it up for the connections you have available on the Rotel you are using. Hope this helps, Jeff

These are actual pictures of the equipment you have so it should be fairly simple to hook up.

[bwanac]

Thanks... this is what I was trying to avoid.. as the Sony spring clips are not that great and I feel I will have a large degradation of signal going through the sub. Very useful charts though.

[Grandpaw]

I bought a new amplifier. Previously I had my sub woofer connect to the Sub woofer Out on my receiver. This new amp does not feature this. Now I know there may be a couple options to wiring it onto this amp.

Here I read you bought a new amp and it doesn't have the same connection. Asking questions BEFORE purchasing new equipment might prove to be a better option.

Gear: Rotel ra 985bx
platinum audio pt801
sony sa wm40

So this is my dilemna. Right now I just have the platinums connected to the Speaker A on the Rotel. Sounds great! Now, can I wire the Sony to the Speaker B and then turn the selection to Speaker A+B? Or is that no good?

If you asking will it blow up, that answer is no.

The other option is the trusted running the signal through the subs high-level speaker inputs and then to the mains. However, since the Sony is not the greatest of sub, will I lose much clarity running through it? Or will signal degradation be minimal?

This was the second option and you ask the question , Will I lose much clarity running it this way? Seems you already had your mind made up against this option according to your later comments.

Any of the options will work and not hurt your stereo. I researched your equipment and in the manual it says with the combination of equipment you listed, the preffered method to hook it up is like the picture I provided.

I would love to keep the Platinums directly wired to the Rotel and wire the sub up seperaratly, but Im thinking this is not really an option. Help

If you give two options and don't want to use one of them, I have to wonder what was the point of asking which option is better in the first place.

Good luck on getting the best sound, Jeff

[bwanac]

No offense. I appreciate the help. I am just looking for the best quality method and i see the weak point in my system as the sub. However, I may just be falling into the crazy intracacies of audiophile world.

I knew the amp did not have dedicated sub out, most int. amps do not.

Maybe you can help with this. If I run sub to speaker b, and mains to a, then they are in series right? I am trying to understand the flow of the signal. Do you know how this works?

Letme get a picture. Like below but the sub is just like another speaker in the series, receiving its signal last. Or is it different.

http://www.termpro.com/articles/images/image33.gif

[bfalls]

Most receivers I've seen have the 'A' and 'B' speakers in parallel. I'm not certain about integrated amps, but feel it's probably the same. Connecting two pair of speakers in parallel reduces the impedance ( (R1xR2) / (R1+R2) ). Many subs are 4 ohm, so if you parallel the sub with an 8 ohm speaker the resulting "nominal" impedance would be 2.67 ohms, a difficult continuous load for most amps. Even impedance is even lower if speakers and sub are 4 ohm (2 ohm).

If the integrated amp can handle the increased current from the low impedance you're OK, but it's far from ideal and doesn't provide any real added value.

The option stated by your instructions and supported by GRANDPA should work well, that's how the sub was designed. Since the sub is powered, it shouldn't increase the load on the amp, nor should you lose fidelity. If you're that concerned about sound, why buy a Sony sub? I like their video products, but they're not known for their speakers. A sub from SVS, HSU, Velodyne, PAradigm or others would suit better.

[bwanac]

I bought the sub a while ago when I was not too concerned with overall sound. It was well reviewed for the price. So I bought it.

So, I undid the sub for a few days. The sound was really nice. However, when I cracked it I found that my Platinums can not handle all the power. Distorition came in far to early. So I decided to wire up the sony, despite the damn spring clips. With the subs internal crossover the sound can be up and distortion free. I feel like I lost a little clarity from the Platinums this way, but I will maintain this for now until I feel the need to upgrade again.