Connecting a subwoofer with stereo and homecinema amps

[dakchi]

Hello,

I am sorry if this question has already been asked, but I couldn't find any answear in the forum. Basically I have a B&W PV1 subwoofer that has one line input and a stereo (cambridge cxa80) and a homecinema (denon 2311) amps. Both amps have a output connection to the subwoofer. How can I connect the subwoofer to the 2 amps in order to be used for hifi and homecinema?

Many thanks for your help

 

[andyjm]

Hello,

I am sorry if this question has already been asked, but I couldn't find any answear in the forum. Basically I have a B&W PV1 subwoofer that has one line input and a stereo (cambridge cxa80) and a homecinema (denon 2311) amps. Both amps have a output connection to the subwoofer. How can I connect the subwoofer to the 2 amps in order to be used for hifi and homecinema?

Many thanks for your help

If I understand the question correctly, you have two outputs, one from your stereo and one from your home cinema. You want to connect both outputs to a single input on your sub. All connections are line level.

What you can't do is just connect the two outputs together. The technical issue is that line level outputs are low impedance, line level inputs are high impedance. The two outputs will fight each other.

The easy solution is to use a simple 'two in one out' switchbox, these are available with a variety of connection types for a few £ on eBay or Amazon.

You could build a 'voltage adder' if you are handy with a soldering iron. A 1Kohm resistor in series with each output, before connecting them both to the sub input. That will allow either amp to drive the sub without ill effects.

 

[insider9]

You're using a sub with RX6s? How big is your room?

 

[dakchi]

Thank you for your answear. Are you refering to an RCA switch that I would use with phono cables?

 

[dakchi]

My room is 30 m2. If I have a subwoofer that can give more bass to my stereo audio, why not using it?

 

[Samd]

Doesn't it matter that the stereo amp nor the sub itself will have control over crossover please?

 

[andyjm]

Thank you for your answear. Are you refering to an RCA switch that I would use with phono cables?

Yes.

Both eBay and Amazon have a large number of different boxes available. Most are stereo, but in your application you could just use one channel and ignore the other channel on the switch. These are simple mechanical switches, so are bi-directional. You can buy a '2 into 1' or '1 into 2' - it will work the same way. Sometimes they are listed as A/B switches.

They are also cheap - £15 or less.

Electrically it is the same as unplugging one amp from the sub and plugging the other amp in. It is just more convenient to have a switch than scrabble around the back of the sub each time you want to make a change.

 

[andyjm]

Doesn't it matter that the stereo amp nor the sub itself will have control over crossover please?

The OP was asking about the electrical connections. Setting up the sub crossover and phase are a different subject - but will also need to be addressed.

 

[insider9]

Integration will be a nightmare for the setup you have in mind. It would be difficult enough to integrate the sub with your RX6s go get good results for music. With the bass you get from them already I personally wouldn't even try. It will be very frustrating Sure you can play about but would not expect great results.

When adding another set of speakers and amp and to that it would be even more difficult.

The main question is how will you set the crossover on the sub? If it will be working well with your MA it's bound to be too low for your other speaker.

 

[insider9]

Doesn't it matter that the stereo amp nor the sub itself will have control over crossover please?

The OP was asking about the electrical connections.  Setting up the sub crossover and phase are a different subject - but will also need to be addressed.

+1

OP if you want to experiment that's quite ok. I'd first attempt to see of you can get results you're happy with when manually switching the cable. If so then and only then I'd go with the solution given by Andyjm. Otherwise you may be spending money on something that's ultimately will reside in a cupboard.

 

[dakchi]

You are right. I have just tested the subwoofer with the MO and it adds too much bass. I almost cannot hear the singer

 

[macdiddy]

then try adjusting the volume control on the sub.

*music2*

 

[Al ears]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

 

[Samd]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

..some further explanation of your second sentence. Reckon as I got the first one OK!

 

[Al ears]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

..some further explanation of your second sentence. Reckon as I got the first one OK!

In my opinion, subwoofers were never designed to supplement a pure stereo set-up and they were there originally to supplement the odd bang / thud required by home theatre systems to bring them more in line with a cinema experience.

The number of threads we have on this forum bemoaning the inability to integrate them correctly into a system they were not designed for proves my point.

If you need a sub in a stereo system you have the wrong speakers to start with.

If you try to integrate a sub into a system without the utilization of a true 2.1 amplifier you are going to get yourself into a whole new world of grief...... simples!

 

[shadders]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

..some further explanation of your second sentence. Reckon as I got the first one OK!

In my opinion, subwoofers were never designed to supplement a pure stereo set-up and they were there originally to supplement the odd bang / thud required by home theatre systems to bring them more in line with a cinema experience.

The number of threads we have on this forum bemoaning the inability to integrate them correctly into a system they were not designed for proves my point.

If you need a sub in a stereo system you have the wrong speakers to start with.

If you try to integrate a sub into a system without the utilization of a true 2.1 amplifier you are going to get yourself into a whole new world of grief...... simples!

Hi,

Is there any requirement for time delay correction for a sub woofer which is integrated with the hifi setup? Is it an issue at all?

Regards,

Shadders.

 

[andyjm]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

..some further explanation of your second sentence. Reckon as I got the first one OK!

In my opinion, subwoofers were never designed to supplement a pure stereo set-up and they were there originally to supplement the odd bang / thud required by home theatre systems to bring them more in line with a cinema experience.

The number of threads we have on this forum bemoaning the inability to integrate them correctly into a system they were not designed for proves my point.

If you need a sub in a stereo system you have the wrong speakers to start with.

If you try to integrate a sub into a system without the utilization of a true 2.1 amplifier you are going to get yourself into a whole new world of grief...... simples!

Hi,

Is there any requirement for time delay correction for a sub woofer which is integrated with the hifi setup? Is it an issue at all?

Regards,

Shadders.

Depends where you place the sub.

Drivers in a single box are co-located, so while phase matters there are no gross timing errors. Same would not be true of a separate sub.

Have the sub the same distance to your ears as the main boxes and you should be OK though.

 

[shadders]

then try adjusting the volume control on the sub.

*music2*

Better still don't bother. The correct integration of a sub into a stereo HiFi system defeats the object of having a good stereo system in the vast majority of cases.

..some further explanation of your second sentence. Reckon as I got the first one OK!

In my opinion, subwoofers were never designed to supplement a pure stereo set-up and they were there originally to supplement the odd bang / thud required by home theatre systems to bring them more in line with a cinema experience.

The number of threads we have on this forum bemoaning the inability to integrate them correctly into a system they were not designed for proves my point.

If you need a sub in a stereo system you have the wrong speakers to start with.

If you try to integrate a sub into a system without the utilization of a true 2.1 amplifier you are going to get yourself into a whole new world of grief...... simples!

Hi,

Is there any requirement for time delay correction for a sub woofer which is integrated with the hifi setup? Is it an issue at all?

Regards,

Shadders.

Depends where you place the sub.

Drivers in a single box are co-located, so while phase matters there are no gross timing errors. Same would not be true of a separate sub.

Have the sub the same distance to your ears as the main boxes and you should be OK though.

Hi,

Thanks.

Regards,

Shadders.