dual subs from 1 output

[buckshot]

i'm currently upgrading my surround system piece by piece. i bought new floor standing speakers, got all new wiring and cables (monoprice.com), and am going to upgrade my receiver to an onkyo tx-sr674. i also want to get a velodyne 12" sub. what i want to know is; can i use both my old sub and the new one but with only 1 sub output from the receiver? would it significantly imapct the performance of both subs? it would be nice to have subs at both sides of my room, but not at the cost of quality.

i know little of surround sound systems if its not easy to tell.

[WriteSimply]

Just split the signal from the receiver. That's it.


fuad

[buckshot]

Originally Posted by WriteSimply

Just split the signal from the receiver. That's it.


fuad

wouldn't that cut the signal strength in half? will that affect the quality of the sub's output? if its that simple that will be awesome,

[Kaldaim]

As long as the cables are good quality and aren't running a long distance, you should not notice a difference in sound quality. Try the Velodyne by itself first, though, because if the old sub is a lower quality it might make your low end sound worse.

[buckshot]

Originally Posted by Kaldaim

As long as the cables are good quality and aren't running a long distance, you should not notice a difference in sound quality. Try the Velodyne by itself first, though, because if the old sub is a lower quality it might make your low end sound worse.

its not so much that my old sub is worse, as it lacks the size and power necessary to be the main sub. i've never had the "fart" or bottoming out. so i figured having the velodyne as the main sub at the front of the room and the old one behind the couch just to give a little more ambiance. thanks for the imput. i'd appreciate any further input anyone has.

[WriteSimply]

Well can your old sub be hooked up to your surrounds? If you can do that, then you can use it to drive the bass for the surround speakers (changing the speaker settings to LARGE) then use the Velodyne as the main sub.


fuad

[deathscripture]

you may have to bridge them. You will start running in ohm reducing problems otherwise. Check to see the impedance on the subs before or you might damage something.

But I am not terribly knowledgeable, so wait for a more definitive answer from someone who knows.

[MatrixS2000]

Originally Posted by buckshot

wouldn't that cut the signal strength in half? will that affect the quality of the sub's output? if its that simple that will be awesome,

Yes, you will drop the input signal by 3dB which is half.

If you have a sub adjustment, just raise the output by 3 dB (doubles it).

I have an Earthquake sub that I run off 2 channels of my Parasound amp, so I am doing exactly what you are trying to do but with a single sub - I run 2 amplifier channels off a single output from my processor...

You should tell us what your previous sub was....

[buckshot]

Originally Posted by MatrixS2000

Yes, you will drop the input signal by 3dB which is half.

If you have a sub adjustment, just raise the output by 3 dB (doubles it).

I have an Earthquake sub that I run off 2 channels of my Parasound amp, so I am doing exactly what you are trying to do but with a single sub - I run 2 amplifier channels off a single output from my processor...

You should tell us what your previous sub was....

but that leaves me open to ridicule.

its an onkyo sub. not exactly high end, but to justify myself it came with the surround system i'm replacing. and I haven't had any problems with it. I can't remember the model # but I believe its an 8'' downfiring sub. its powered but I don't know the wattage.

[Filterlab]

To be blatantly honest, a Velodyne sub is pretty well the finest around. You won't need your Onkyo sub. Sell it and use the cash for some BDs.

Also having two different subs may cause frequency cancellation. This in effect makes two subs into zero subs. Not something you want after spending your hard earned on a Velodyne.

[buckshot]

Originally Posted by Filterlab

To be blatantly honest, a Velodyne sub is pretty well the finest around. You won't need your Onkyo sub. Sell it and use the cash for some BDs.

Also having two different subs may cause frequency cancellation. This in effect makes two subs into zero subs. Not something you want after spending your hard earned on a Velodyne.

that was the other option. but I wanted to see if it would work before I tried to get rid of it. i'm selling off a lot of my dvd sets to feed my bd addiction.

anyone want band of brothers box set?

[DavePS3]

If you've got speaker connections on that sub, you could just use your leads from your rear speakers into the sub then another pair of wires out to the rears, that would give you more bass punch in the rears... or you could even do that with your center channel if it sounds a little thin on it's own.

[MatrixS2000]

Originally Posted by Filterlab

Also having two different subs may cause frequency cancellation.

Only if they were out of phase...if not, you will get more air displacement, however, depending on the sub and we don't have any details on the onkyo sub, I cannot state whether it would be useful.

[MatrixS2000]

Originally Posted by DavePS3

If you've got speaker connections on that sub, you could just use your leads from your rear speakers into the sub then another pair of wires out to the rears, that would give you more bass punch in the rears... or you could even do that with your center channel if it sounds a little thin on it's own.

That would work well - just select your rear speakers as being large.

[buckshot]

Originally Posted by MatrixS2000

That would work well - just select your rear speakers as being large.

i'm pretty sure I have the speaker inputs in the rear of the onkyo. i'm working overtime to be able to afford the may 22nd and june 5th onslaught, but i'm going to run home and try the sub with the rears speakers.

do I run separate wires from the receiver to the sub + rear channels or do I run from receiver to sub then sub to speakers?

thanks again everyone.

[MatrixS2000]

Originally Posted by buckshot

i'm pretty sure I have the speaker inputs in the rear of the onkyo. i'm working overtime to be able to afford the may 22nd and june 5th onslaught, but i'm going to run home and try the sub with the rears speakers.

do I run separate wires from the receiver to the sub + rear channels or do I run from receiver to sub then sub to speakers?

thanks again everyone.

Receiver rear speakers out--->sub speaker inputs, sub speaker outputs---> rear speakers.

What this does is take line level in to the sub, where it passes a filter, lows are sent to the sub's amplifier section, the rest to your rear speakers.

[Deciazulado]

In the case you decide to use the old sub as an extra sub (your original question) heres my quick advice/overview. You get a Y cable from the receivers sub output splitting the to conect the two powered subs to it. To calibrate you can unplug the old sub (or not connect it inintialy), and calibrate the new more powerful sub first. (you know position, phase (if it has phase control), and level, to integrate with the main system speakers.) Then you conect the second one, and do same while both subs are runing in this order: you position the second woofer so that in the main listening area it augments the bass, (having a strong friend and level meter to do these things always helps a lot!), you adjust the phase for maximum bass too (if the old sub has phase control) , and then you'll have to measure sub levels again , probabky decreasing the previously measured sub levels to around up 3dB lower (as you have now increased the ball sound level up to 3dB higher (doubled as MatrixS2000 said) by the second suv (ymmv). If the second sub has a crossover cut off frequency control on it, you probably might want to set it to the lowest frequency, so that only the lowest lows (the hardest to reproduce, the one where the sub's outputs are already declining) are the only ones that are doubled or increased (kind of adding a sub sub signal :-P) so you flatten the low low end by increasing it. You'll probably have a little less distortion on the lows that way too (one of the benefits of spreading the power through several speakers) if you ever get all things optimal!

[buckshot]

I opened the fry ad for today and they have velodyn 10'' 150 watt VX-10C for $149 a piece. if they sound good I may pick up 2 of them. anyone have an opinion on these? I haven't been able to find anything but good reviews online.