sub hookups

[davenlo]

Would hooking up sub and speakers in parallel from amp from L/R speaker outputs on amp cause an impedence problem for amp? I have no sub out from amp so only choise is to go speaker level.

 

[Adam]

Welcome to the forum!

Hooking up any set of speakers in parallel could potentially cause an impedance issue.

Which receiver, speakers, and sub do you have?

Adam

 

[davenlo]

Thanks Adam: I have a pioneer SX-205 amp (100 watt/ch) Two Cerwin Vega bookshelf 6 in speakers and an AR 100watt powered sub.

 

[Adam]

Do you know the model numbers of the speakers and/or sub? That would help us look up information on them. Thanks.

 

[davenlo]

The AR sub model # is S12HO. Can't find any info on Vegas. They are 6in two way bookshelf. All are 8 oms. Thanks

 

[Adam]

Thanks.

I've been trying to find more info on that sub, but I haven't, yet.

I hope that this doesn't sound insulting - does the sub have speaker-level outputs on it?

 

[markw]

It shouldn't be a problem.

Remember, a powered subwoofer isn't just a low impedance speaker.

It's the input stage of a crossover/combiner/amplifier which presents a high impedance load to the driving receiver/amplifier.

It's high impedance is all but invisible to the driving amp, particularly at the low end.

 

[OttoMatic]

Remember, a powered subwoofer isn't just a low impedance speaker.

It's the input stage of a crossover/combiner/amplifier which presents a high impedance load to the driving receiver/amplifier.

It's high impedance is all but invisible to the driving amp, particularly at the low end.

That's right, and that means that you should be able to hook up your sub and mains in parallel from the speaker level outputs of your receiver or amp. It should not cause the impedance of the main speakers to drop (a high impedance in parallel with a low impedance will be seen as the low impedance) and it will draw very little current (which means that you will have no decrease in power delivered to the speakers from the amp).

I think you'll be fine. Hook it up, start with low levels on the volume knob and see what you think.

 

[davenlo]

Not at all. Yes it does have speaker level imputs and thats how it's hooked up. Thanks Dave.

 

[Pyrrho]

Remember, a powered subwoofer isn't just a low impedance speaker.

It's the input stage of a crossover/combiner/amplifier which presents a high impedance load to the driving receiver/amplifier.

It's high impedance is all but invisible to the driving amp, particularly at the low end.

Absolutely. I once looked at a circuit for a powered subwoofer that I had, and for the speaker level inputs, it put about 50k ohms in the circuit. A quick calculation of 50k in parallel with any normal impedance speaker will show that the drop in impedance over just the speaker is completely trivial.

The large resistance, of course, serves two functions:

1. It reduces the level of the signal to more or less normal preamp levels for the subwoofer's onboard amplifier to deal with.
2. It keeps the impedance of the powered subwoofer high enough for it to be safely put in parallel with pretty much any speaker and not damage the amplifier used to drive the main speakers (while also providing the input for the subwoofer).

 

[Midcow2]

you might consider upgrading your AVR

I know this isn't what you asked for but you best bet is to upgrade your AVR to at least a 2.1 Yamaha makes a nice inexpensive ( as opposed to cheap) AVR that would handle you system very well the Yamaha RX-V363. It is 5.1 system and would laso allow you to add a center speaker and rear surrounds.

It sells for as low as $179
http://www.spytown.com/yarx5dihothr.html?productid=yarx5dihothr&channelid=NEXTA

Good Luck!

MidCow2

 

[phlakvest]

Does the sub have the 4 pinch type speaker wire terminals... one set marked input, one set marked output?

If thats the case then is supposed to be hooked up that way unless you have a LFE (sub channel) output on your reciever.

 

[OttoMatic]

Wow, to whoever gave me the red chicklet for suggesting to connect a powered sub to speaker level outptus -- you're awesome! Just look at everyone else suggesting to hook a powered sub to the speaker level outpus of the receiver. It's a trivial exercise to reduce speaker level inputs to whatever voltage is required by the input section of the sub's amp. Many subs offer speaker level inputs on the amp. I take it you don't know much about electronics. Too bad you didn't speak up in the thread...

 

[Pyrrho]

Wow, to whoever gave me the red chicklet for suggesting to connect a powered sub to speaker level outptus -- you're awesome! Just look at everyone else suggesting to hook a powered sub to the speaker level outpus of the receiver. It's a trivial exercise to reduce speaker level inputs to whatever voltage is required by the input section of the sub's amp. Many subs offer speaker level inputs on the amp. I take it you don't know much about electronics. Too bad you didn't speak up in the thread...

I wouldn't let it bother you that there are people who do that sort of thing. Seeing your post got me to check the latest for myself, and I found that I received a "red chicklet" for a post in another thread very recently. In my case, the person had the courtesy to leave a comment with it that demonstrated their stupidity beyond any doubt. Normally, I don't pay any attention at all to such things, and I recommend that you do likewise. But if you must pay attention to such things, just remember, judging from all that green you have, it is a small minority opinion that you deserve "red". You will never please everybody.

 

[OttoMatic]

I wouldn't let it bother you that there are people who do that sort of thing. Seeing your post got me to check the latest for myself, and I found that I received a "red chicklet" for a post in another thread very recently. In my case, the person had the courtesy to leave a comment with it that demonstrated their stupidity beyond any doubt. Normally, I don't pay any attention at all to such things, and I recommend that you do likewise. But if you must pay attention to such things, just remember, judging from all that green you have, it is a small minority opinion that you deserve "red". You will never please everybody.

Thanks, man. It doesn't really bug me, but I wanted to post it in public since it was so wrong! No big deal; kinda funny.