subwoofer cable question

[Albert Ng]

Hi all.

I have an oldish Yamaha YST500 sub. Its a 10" driver with 120 W on board.

At the moment, its going into my Onkyo TX800 amp via the pre out on the back
of the amp - into the single "L" rca input.

Just wondering, am I better of going "Stereo" from the sub (L and R) into
the single rca pre out on the amp.

Will I get more powerful bass?

[Lucas Tam]

"Albert Ng" <no@home.com> wrote in news:cMuSd.170402$K7.30988@news-
server.bigpond.net.au:

>
> Just wondering, am I better of going "Stereo" from the sub (L and R) into
> the single rca pre out on the amp.
>
> Will I get more powerful bass?
>

You'll get a more accurate bass signal I guess.

--
Lucas Tam (REMOVEnntp@rogers.com)
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

[rdclark]

Albert Ng wrote:
> Hi all.
>
> I have an oldish Yamaha YST500 sub. Its a 10" driver with 120 W on
board.
>
> At the moment, its going into my Onkyo TX800 amp via the pre out on
the back
> of the amp - into the single "L" rca input.
>
> Just wondering, am I better of going "Stereo" from the sub (L and R)
into
> the single rca pre out on the amp.
>
> Will I get more powerful bass?

Your sub has a mono amp. You're feeding it a mono signal. There's
nothing to be gained from splitting the mono signal from the receiver
only to have the sub simply combine it again.

(PS: I got confused by directionality in your post. The signal is going
OUT of the Preamp Out and IN to the subwoofer input. You're making a
connection from an OUTPUT on the receiver to an INPUT on the sub.)

RichC

[Lucas Tam]

"rdclark" <rdclark2@comcast.net> wrote in news:1109087016.613464.314690
@c13g2000cwb.googlegroups.com:

> Your sub has a mono amp. You're feeding it a mono signal. There's
> nothing to be gained from splitting the mono signal from the receiver
> only to have the sub simply combine it again.

You do gain a more balanced signal. i.e. If there is low bass on the right
channel but not on the left channel, a stereo input would reflect the bass
in the right channel.



--
Lucas Tam (REMOVEnntp@rogers.com)
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

[RicSeyler]

I always used both sub outs on my receiver to drive a sub with 2 imputs.

Albert Ng wrote:

>Hi all.
>
>I have an oldish Yamaha YST500 sub. Its a 10" driver with 120 W on board.
>
>At the moment, its going into my Onkyo TX800 amp via the pre out on the back
>of the amp - into the single "L" rca input.
>
>Just wondering, am I better of going "Stereo" from the sub (L and R) into
>the single rca pre out on the amp.
>
>Will I get more powerful bass?
>
>
>
>

--
Ric Seyler

[rdclark]

Lucas Tam wrote:
> "rdclark" <rdclark2@comcast.net> wrote in
news:1109087016.613464.314690
> @c13g2000cwb.googlegroups.com:
>
> > Your sub has a mono amp. You're feeding it a mono signal. There's
> > nothing to be gained from splitting the mono signal from the
receiver
> > only to have the sub simply combine it again.
>
> You do gain a more balanced signal. i.e. If there is low bass on the
right
> channel but not on the left channel, a stereo input would reflect the
bass
> in the right channel.

1) If he has the receiver I think he does, he's using one of the
6-channel preamp-outs to drive the sub. It's a mono source.

2) Even when you have a stereo full-range source (not the case here), a
mono subwoofer will combine the channels at the input stage. There
would be no difference, electronically, between using both inputs on
the sub vs using a Y connector outside the sub. There's only one amp
and only one speaker.

RichC

[rdclark]

RicSeyler wrote:
> I always used both sub outs on my receiver to drive a sub with 2
imputs.

Most subs are designed so they can be used more than one way. In a
standard stereo configuration, some subs are designed to have the
full-range speakers connected to terminals on the sub. In that case,
there must be stereo inputs so that there can be stereo outputs.

That doesn't change the fact that the channels are combined before
going to the sub's own amp and driver, and that if you're driving it
with a mono source, there's no purpose served by connecting two cables
to it when each carries identical information.

RichC

[RicSeyler]

I've even read from some manufacturers that it is recommended
to drive both imputs on their subs from receivers with 2 LFE outputs. FWIW.

rdclark wrote:

>RicSeyler wrote:
>
>
>>I always used both sub outs on my receiver to drive a sub with 2
>>
>>
>imputs.
>
>Most subs are designed so they can be used more than one way. In a
>standard stereo configuration, some subs are designed to have the
>full-range speakers connected to terminals on the sub. In that case,
>there must be stereo inputs so that there can be stereo outputs.
>
>That doesn't change the fact that the channels are combined before
>going to the sub's own amp and driver, and that if you're driving it
>with a mono source, there's no purpose served by connecting two cables
>to it when each carries identical information.
>
>RichC
>
>
>

--
Ric Seyler

[rdclark]

RicSeyler wrote:
> I've even read from some manufacturers that it is recommended
> to drive both imputs on their subs from receivers with 2 LFE outputs.
FWIW.

Following the manufacturer's instructions is always a good idea. But
since there is only one LFE channel, it's hard to imagine what purpose
would be served. Voltage is voltage, and mono is mono.

In the present case, however, the question is moot: there is only one
LFE output on the receiver, if it is in fact an Onkyo TX-SR800.

RichC

[steve]

Which ones are those? The subs I own, say using only the R or L input
from the LFE is appropriate.

> RicSeyler wrote:
>
> I've even read from some manufacturers that it is recommended
> to drive both imputs on their subs from receivers with 2 LFE outputs.
> FWIW.
>
> rdclark wrote:
>
> > RicSeyler wrote:
> >
> >
> >> I always used both sub outs on my receiver to drive a sub with 2
> >>
> >>
> > imputs.
> >
> > Most subs are designed so they can be used more than one way. In a
> > standard stereo configuration, some subs are designed to have the
> > full-range speakers connected to terminals on the sub. In that case,
> > there must be stereo inputs so that there can be stereo outputs.
> >
> > That doesn't change the fact that the channels are combined before
> > going to the sub's own amp and driver, and that if you're driving it
> > with a mono source, there's no purpose served by connecting two
> > cables
> > to it when each carries identical information.
> >
> > RichC
> >
> >
> >
>
> --
> Ric Seyler

[RicSeyler]

I think it was SVS, Velodyne & B&W, but I'm not going to spend a bunch
of time
to hunt this down....LOL I drove my Velodyne with both inputs.

But for those who don't want, to that's up to them......

steve wrote:

>Which ones are those? The subs I own, say using only the R or L input
>from the LFE is appropriate.
>
>
>
>>RicSeyler wrote:
>>
>>I've even read from some manufacturers that it is recommended
>>to drive both imputs on their subs from receivers with 2 LFE outputs.
>>FWIW.
>>
>>rdclark wrote:
>>
>>
>>
>>>RicSeyler wrote:
>>>
>>>
>>>
>>>
>>>>I always used both sub outs on my receiver to drive a sub with 2
>>>>
>>>>
>>>>
>>>>
>>>imputs.
>>>
>>>Most subs are designed so they can be used more than one way. In a
>>>standard stereo configuration, some subs are designed to have the
>>>full-range speakers connected to terminals on the sub. In that case,
>>>there must be stereo inputs so that there can be stereo outputs.
>>>
>>>That doesn't change the fact that the channels are combined before
>>>going to the sub's own amp and driver, and that if you're driving it
>>>with a mono source, there's no purpose served by connecting two
>>>cables
>>>to it when each carries identical information.
>>>
>>>RichC
>>>
>>>
>>>
>>>
>>>
>>--
>>Ric Seyler
>>
>>

--
Ric Seyler

[rdclark]

RicSeyler wrote:
> I think it was SVS, Velodyne & B&W, but I'm not going to spend a
bunch
> of time
> to hunt this down....LOL I drove my Velodyne with both inputs.
>
> But for those who don't want, to that's up to them......

Well, here's a quote from an SVS owner's manual:

"There are a variety of ways to configure your new sub. Usually, a
simple mono, shielded 75 Ohm A/V RCA type cable (a.) is used to take
the subwoofer output of your DD/DTS surround sound receiver (b.) and
feed the low-level input of the sub’s amp. There is no need to
“split” the signal going to the sub (c.). You can feed either one of
the two amp inputs, it doesn’t matter, right or left."

So there. <g>

RichC

[RicSeyler]

LOLOL
But that is in reference to a receiver/amp with only one LFE out.
<wink wink> ;-)

rdclark wrote:

>RicSeyler wrote:
>
>
>>I think it was SVS, Velodyne & B&W, but I'm not going to spend a
>>
>>
>bunch
>
>
>>of time
>>to hunt this down....LOL I drove my Velodyne with both inputs.
>>
>>But for those who don't want, to that's up to them......
>>
>>
>
>Well, here's a quote from an SVS owner's manual:
>
>"There are a variety of ways to configure your new sub. Usually, a
>simple mono, shielded 75 Ohm A/V RCA type cable (a.) is used to take
>the subwoofer output of your DD/DTS surround sound receiver (b.) and
>feed the low-level input of the sub's amp. There is no need to
>"split" the signal going to the sub (c.). You can feed either one of
>the two amp inputs, it doesn't matter, right or left."
>
>So there. <g>
>
>RichC
>
>
>

--
Ric Seyler

[rdclark]

RicSeyler wrote:
> LOLOL
> But that is in reference to a receiver/amp with only one LFE out.
> <wink wink> ;-)

You ought to see somebody about that twitch.

RichC

[RicSeyler]

Naaaaa.............. it keeps me occupied. :-)

rdclark wrote:

>RicSeyler wrote:
>
>
>>LOLOL
>>But that is in reference to a receiver/amp with only one LFE out.
>><wink wink> ;-)
>>
>>
>
>You ought to see somebody about that twitch.
>
>RichC
>
>
>

--
Ric Seyler

[Lucas Tam]

"rdclark" <rdclark2@comcast.net> wrote in news:1109098574.999855.306910
@c13g2000cwb.googlegroups.com:

> Voltage is voltage, and mono is mono.
>

Yes, but if the Left channel has no bass and the right channel does, if you
feed in one channel, it won't produce a sub channel.

--
Lucas Tam (REMOVEnntp@rogers.com)
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

[TCS]

On Tue, 22 Feb 2005 22:34:07 GMT, Lucas Tam <REMOVEnntp@rogers.com> wrote:
>"rdclark" <rdclark2@comcast.net> wrote in news:1109098574.999855.306910
>@c13g2000cwb.googlegroups.com:

>> Voltage is voltage, and mono is mono.
>>

>Yes, but if the Left channel has no bass and the right channel does, if you
>feed in one channel, it won't produce a sub channel.

If you feed it the monophonic subwoofer channel, the left and right
channels have already been combined.

[steve]

Apparently it's not manufacturer related, its model related, due to the
fact Velodyne recommends using a Y cable on some models (to insure
enough signal level is present for auto turn on) and not on others (two
inputs are already Y'd) and some with LFE option to bypass the internal
x-over.

I suppose the best answer would be - consult the owners manual for your
specific model.

I would think a sub with only one line level input would recommend a Y
cable to R/L line level outputs to avoid the problem of missing bass
information from the unconnected channel.

RicSeyler wrote:
>
> I think it was SVS, Velodyne & B&W, but I'm not going to spend a bunch
> of time
> to hunt this down....LOL I drove my Velodyne with both inputs.
>
> But for those who don't want, to that's up to them......
>
> steve wrote:
>
> >Which ones are those? The subs I own, say using only the R or L input
> >from the LFE is appropriate.
> >
> >
> >
> >>RicSeyler wrote:
> >>
> >>I've even read from some manufacturers that it is recommended
> >>to drive both imputs on their subs from receivers with 2 LFE outputs.
> >>FWIW.
> >>
> >>rdclark wrote:
> >>
> >>
> >>
> >>>RicSeyler wrote:
> >>>
> >>>
> >>>
> >>>
> >>>>I always used both sub outs on my receiver to drive a sub with 2
> >>>>
> >>>>
> >>>>
> >>>>
> >>>imputs.
> >>>
> >>>Most subs are designed so they can be used more than one way. In a
> >>>standard stereo configuration, some subs are designed to have the
> >>>full-range speakers connected to terminals on the sub. In that case,
> >>>there must be stereo inputs so that there can be stereo outputs.
> >>>
> >>>That doesn't change the fact that the channels are combined before
> >>>going to the sub's own amp and driver, and that if you're driving it
> >>>with a mono source, there's no purpose served by connecting two
> >>>cables
> >>>to it when each carries identical information.
> >>>
> >>>RichC
> >>>
> >>>
> >>>
> >>>
> >>>
> >>--
> >>Ric Seyler
> >>
> >>
>
> --
> Ric Seyler

[Lucas Tam]

TCS <The-Central-Scrutinizer@p.o.b.o.x.com> wrote in
news:slrnd1ne60.3d4.The-Central-Scrutinizer@linux.client.comcast.net:

>>Yes, but if the Left channel has no bass and the right channel does,
>>if you feed in one channel, it won't produce a sub channel.
>
> If you feed it the monophonic subwoofer channel, the left and right
> channels have already been combined.

Yes that is my point. The sub will combine the signals. But if you feed in
a single signal to the sub, it will have nothing to combine.

--
Lucas Tam (REMOVEnntp@rogers.com)
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

[Albert Ng]

So do I need one or not? :)

[RicSeyler]

Does your receiver have 2 LFE outs?
And does your sub have 2 line level inputs?
If so I'd run 2 separate cables.

If your Receiver has 2 LFE outs and the sub has
one line level in, I'd do a y-cable.

If your Receive has 1 LFE out and your sub has 2 line level ins
then, maybe y-cable, to me that would be a try it and see situation.

If your receiver has 1 LFE out and the sub has 1 line level in, No extra
cable..



Albert Ng wrote:

>So do I need one or not? :)
>
>
>
>

--
Ric Seyler

[rdclark]

Albert Ng wrote:
> So do I need one or not? :)

No.

RichC

[rdclark]

Lucas Tam wrote:
> "rdclark" <rdclark2@comcast.net> wrote in
news:1109098574.999855.306910
> @c13g2000cwb.googlegroups.com:
>
> > Voltage is voltage, and mono is mono.
> >
>
> Yes, but if the Left channel has no bass and the right channel does,
if you
> feed in one channel, it won't produce a sub channel.

There is no such thing as a "left" or "right" LFE channel. An LFE
channel is by definition mono.

RichC

[rdclark]

Lucas Tam wrote:
> TCS <The-Central-Scrutinizer@p.o.b.o.x.com> wrote in
> news:slrnd1ne60.3d4.The-Central-Scrutinizer@linux.client.comcast.net:

>
> >>Yes, but if the Left channel has no bass and the right channel
does,
> >>if you feed in one channel, it won't produce a sub channel.
> >
> > If you feed it the monophonic subwoofer channel, the left and right
> > channels have already been combined.
>
> Yes that is my point. The sub will combine the signals. But if you
feed in
> a single signal to the sub, it will have nothing to combine.

If you are using a subwoofer as part of a two-channel full-range system
then yes, both the left and right channels need to get to the sub, one
way or another.

In a surround system with a .1 channel, all bass that's intended for
the sub is combined into mono by the decoder.

All standard forms of digital bass management produce mono subwoofer
signals.

RichC

[Lucas Tam]

"rdclark" <rdclark2@comcast.net> wrote in news:1109175496.804485.245610
@g14g2000cwa.googlegroups.com:

>> Yes, but if the Left channel has no bass and the right channel does,
> if you
>> feed in one channel, it won't produce a sub channel.
>
> There is no such thing as a "left" or "right" LFE channel. An LFE
> channel is by definition mono.
>

I know, I meant from a full range stereo signal.

Maybe I misinterpreted the original q :)

--
Lucas Tam (REMOVEnntp@rogers.com)
Please delete "REMOVE" from the e-mail address when replying.
http://members.ebay.com/aboutme/coolspot18/

[RicSeyler]

LOL

What you are saying makes sense Rich,
and he will probably be just fine with one hook up.

But depending on what I end up getting to replace
my Ivan ruined theater I will probably still run two
hook ups on mine. But that's just me. :-)
Probably going with the Denon 3805 and the B&W
setup, 604 frts, 603 rears, ASW 675 sub & LCR600 center.


rdclark wrote:

>Albert Ng wrote:
>
>
>>So do I need one or not? :)
>>
>>
>
>No.
>
>RichC
>
>
>

--
Ric Seyler

[steve]

Lucas Tam wrote:
>
> "rdclark" <rdclark2@comcast.net> wrote in news:1109175496.804485.245610
> @g14g2000cwa.googlegroups.com:
>
> >> Yes, but if the Left channel has no bass and the right channel does,
> > if you
> >> feed in one channel, it won't produce a sub channel.
> >
> > There is no such thing as a "left" or "right" LFE channel. An LFE
> > channel is by definition mono.
> >
>
> I know, I meant from a full range stereo signal.
>
> Maybe I misinterpreted the original q :)
>
If the receiver only has R/L line level RCA outputs and the sub has R/L
line level RCA inputs, connect R to R, L to L. If the sub only has one
RCA input, use a Y cable to combine R/L from the receiver.

[Albert Ng]

the reciever has 1 output, the sub 2, a L and R.

Thanks!


"RicSeyler" <ricseyler@SPAMgulf.net> wrote in message
news:PX1Td.20295$u87.18768@bignews6.bellsouth.net. ..
> Does your receiver have 2 LFE outs?
> And does your sub have 2 line level inputs?
> If so I'd run 2 separate cables.
>
> If your Receiver has 2 LFE outs and the sub has
> one line level in, I'd do a y-cable.
>
> If your Receive has 1 LFE out and your sub has 2 line level ins
> then, maybe y-cable, to me that would be a try it and see situation.
>
> If your receiver has 1 LFE out and the sub has 1 line level in, No extra
> cable..
>
>
>
> Albert Ng wrote:
>
> >So do I need one or not? :)
> >
> >
> >
> >
>
> --
> Ric Seyler
>
>

[rdclark]

Albert Ng wrote:
> the reciever has 1 output, the sub 2, a L and R.

No, the sub has two INPUTS.

Anyway, as I responded previously, your Onkyo (as you know) has a
six-channel analog "pre-amp out" group, and the manual tells you to use
the "sub" output from that group to connect the subwoofer.

This is a mono output.

There is nothing to be gained by splitting that output before
connecting it to your subwoofer's input; the sub will just immediately
recombine it.

If the bass isn't loud enough, turn it up.

RichC

[steve]

Albert Ng wrote:
>
> the reciever has 1 output, the sub 2, a L and R.
>
> Thanks!

You will likely find using a Y cable to the L and R on the sub won't
give you any more bass than using either the L or R by itself. But in
case it does, enjoy the additional bass.

>
> "RicSeyler" <ricseyler@SPAMgulf.net> wrote in message
> news:PX1Td.20295$u87.18768@bignews6.bellsouth.net. ..
> > Does your receiver have 2 LFE outs?
> > And does your sub have 2 line level inputs?
> > If so I'd run 2 separate cables.
> >
> > If your Receiver has 2 LFE outs and the sub has
> > one line level in, I'd do a y-cable.
> >
> > If your Receive has 1 LFE out and your sub has 2 line level ins
> > then, maybe y-cable, to me that would be a try it and see situation.
> >
> > If your receiver has 1 LFE out and the sub has 1 line level in, No extra
> > cable..
> >
> >
> >
> > Albert Ng wrote:
> >
> > >So do I need one or not? :)
> > >
> > >
> > >
> > >
> >
> > --
> > Ric Seyler
> >
> >

[Albert Ng]

thanks guys.
"RicSeyler" <ricseyler@SPAMgulf.net> wrote in message news:a77Td.21411$u87.8563@bignews6.bellsouth.net.. .
LOL

What you are saying makes sense Rich,
and he will probably be just fine with one hook up.

But depending on what I end up getting to replace
my Ivan ruined theater I will probably still run two
hook ups on mine. But that's just me. :-)
Probably going with the Denon 3805 and the B&W
setup, 604 frts, 603 rears, ASW 675 sub & LCR600 center.


rdclark wrote:

Albert Ng wrote:
So do I need one or not? :)

No.

RichC



--
Ric Seyler

[rdclark]

RicSeyler wrote:

> But depending on what I end up getting to replace
> my Ivan ruined theater I will probably still run two
> hook ups on mine. But that's just me. :-)
> Probably going with the Denon 3805 and the B&W
> setup, 604 frts, 603 rears, ASW 675 sub & LCR600 center.

Now there's a setup I can guarantee won't benefit from two cables! <g>

RichC

[RicSeyler]

LOLOL
<sticks out tongue>
;-)

rdclark wrote:

>RicSeyler wrote:
>
>
>
>>But depending on what I end up getting to replace
>>my Ivan ruined theater I will probably still run two
>>hook ups on mine. But that's just me. :-)
>>Probably going with the Denon 3805 and the B&W
>>setup, 604 frts, 603 rears, ASW 675 sub & LCR600 center.
>>
>>
>
>Now there's a setup I can guarantee won't benefit from two cables! <g>
>
>RichC
>
>
>

--
Ric Seyler
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GPL Handicap 6.35
ricseyler@SPAMgulf.net
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