Best way to connect a subwoofer for music listening

[Jglr]

On the subwoofer. I can't find any info on what you LFE outputs and it seems the crossover frequency isn't user configurable anyway. So what are your main speakers?

Elac Debut B6.2

 

[PierreV]

SVS matching tool gives the following recommendations - not saying this would be perfect, but certainly a decent starting point

Elac F6.2 Debut 2.0 Floorstanding Speaker
Stereo Pre-Amplifier or Receiver:
Recommended Low Pass Filter Frequency Setting (Hz)50 HzRecommended Low Pass Filter Slope (dB/octave)12 dB/octave

https://www.svsound.com/pages/merlin

 

[GGroch]

@Jglr, just use the line outputs from the amplifier IMHO......

DON'T Use the Line Outs for a sub on the Onkyo 9010. The manual says it is a fixed volume line out. These used to be called tape outs (its not a preamp out with variable volume). The subwoofer will not change volume if you hook it there. (Caps used cause if you do it by accident it could be very loud and damage something.)

 

[Jglr]

SVS matching tool gives the following recommendations - not saying this would be perfect, but certainly a decent starting point

Elac F6.2 Debut 2.0 Floorstanding Speaker
Stereo Pre-Amplifier or Receiver:
Recommended Low Pass Filter Frequency Setting (Hz)50 HzRecommended Low Pass Filter Slope (dB/octave)12 dB/octave

https://www.svsound.com/pages/merlin

I actually used that tool when I hooked up my old amp. I'm not confused about what frequency to set my crossover to if I'm setting the frequency on the sub. I'm unclear about whether the amp I have will filter out the high frequencies before they go to the sub.

Also, those are the recommended settings for the f6.2 floorstanding cousins of my bookshelf speakers.

 

[GGroch]

I thought the 2nd Paul McGowan video you posted was very revealing on how a subjectivist (Paul) would hook up a subwoofer. At 2:40 he says to connect the sub using the power amps outputs because we want to capture the "Sound Signature" of your expensive (perhaps PSaudio) amplifier.

It is true that if you hook it up to the amp's speaker outputs, you will be getting the "sound signature" of both your pre-amp and amplifier. Objectivists would argue that what Paul calls sound signature...that is deviation from the original signal, is more correctly termed distortion.

The output of a separate pre-amp will always have lower distortion than the output of a power amp that is plugged into it. The goal of most legitimate amp manufacturers is for their amps to add as little of their own signature as possible. That is also what Amir's amp tests are supposed to show. It is certainly a difference in philosophy, and Paul is consistent.

 

[Jglr]

I thought the 2nd Paul McGowan video you posted was very revealing on how a subjectivist (Paul) would hook up a subwoofer. At 2:40 he says to connect the sub using the power amps outputs because we want to capture the "Sound Signature" of your expensive (perhaps PSaudio) amplifier.

It is true that if you hook it up to the amp's speaker outputs, you will be getting the "sound signature" of both your pre-amp and amplifier. Objectivists would argue that what Paul calls sound signature...that is deviation from the original signal, is more correctly termed distortion.

The output of a separate pre-amp will always have lower distortion than the output of a power amp that is plugged into it. The goal of most legitimate amp manufacturers is for their amps to add as little of their own signature as possible. That is also what Amir's amp tests are supposed to show. It is certainly a difference in philosophy, and Paul is consistent.

That's why I posted my question to this forum. This seems like a rational crowd.

It's disappointing how much advice is given regarding HiFi that is completely based on speculative opinion. Reviews and comparisons of technology should read more like computer benchmarks than wine spectator.

 

[andreasmaaan]

DON'T Use the Line Outs for a sub on the Onkyo 9010. The manual says it is a fixed volume line out. These used to be called tape outs (its not a preamp out with variable volume). The subwoofer will not change volume if you hook it there. (Caps used cause if you do it by accident it could be very loud and damage something.)

Good advice then

TBH, if the manual doesn’t say there is a low pass filter on the sub out, there probably isn’t.

 

[Jglr]

Good advice then

TBH, if the manual doesn’t say there is a low pass filter on the sub out, there probably isn’t.

I disconnected all of my speakers but the sub and ran test tones generated on my phone. The sub out doesn't appear to do any filtering. Mystery solved.

 

[andreasmaaan]

I disconnected all of my speakers but the sub and ran test tones generated on my phone. The sub out doesn't appear to do any filtering. Mystery solved.

Good to hear

 

[Juhazi]

https://www.themasterswitch.com/review-onkyo-a-9110

So, A9110 has sub out without any filtering. It is most likely summed L+R signal that follows master volume. It is just a simple add-on feature, because the amp doesn't have a dsp chip that could do filtering/adjustments.

A subwoofer/amp connected to A9110's sub out must have it's low-pass filter active and then one must find best setting for it's volume, crossover and phase. Best result comes with acoustic measurements, but still leaves some problems, because main speakers' highpass cannot be done.

Connecting sub to speaker outputs gives all same possibilities and problems, in this case. Some subwoofers/amps don't have speaker-level in at all.

 

[LTig]

My amp is an Onkyo A9110 stereo amp. It doesn't have room correction or an option to specify the size of my speakers.

As already reported by @Ron Texas the manual does not reveal whether the mains are rolled off when the subwoofer output is on.

You can find this out by yourself: Disconnect the subwoofer and connect the mains to the amp. Play a track with lots of deep bass (or a test signal with 40 -50 Hz) and toggle between sub on and sub off. For sub on expect less deep bass. If there is no change in bass level the mains are not rolled off, and then you should connect the speakers to the sub as described in your first posting.

Rolling off the mains is very important because it reduces distortion in the mid range and allows higher SPLs.

 

[Jglr]

As already reported by @Ron Texas the manual does not reveal whether the mains are rolled off when the subwoofer output is on.

You can find this out by yourself: Disconnect the subwoofer and connect the mains to the amp. Play a track with lots of deep bass (or a test signal with 40 -50 Hz) and toggle between sub on and sub off. For sub on expect less deep bass. If there is no change in bass level the mains are not rolled off, and then you should connect the speakers to the sub as described in your first posting.

Rolling off the mains is very important because it reduces distortion in the mid range and allows higher SPLs.

If I understand you, you're saying that if the amp isn't filtering out bass to my main speakers, it would be better to run speaker wires from the amp to the sub and from the sub to the main speakers. This is to allow the sub to filter out the bass going to my main speakers?

According to the manual for my subwoofer, when the sub and speakers are connected this way, there is no high pass filter. The entire signal is passed to the mains.

I might run the test you suggest anyway just to see.

 

[Jglr]

If I understand you, you're saying that if the amp isn't filtering out bass to my main speakers, it would be better to run speaker wires from the amp to the sub and from the sub to the main speakers. This is to allow the sub to filter out the bass going to my main speakers?

According to the manual for my subwoofer, when the sub and speakers are connected this way, there is no high pass filter. The entire signal is passed to the mains.

I might run the test you suggest anyway just to see.

As far as I can tell, the amp seems to output the same amount of bass to the main speakers in direct mode when the sub out is on or off.

 

[Tircuit]

I disconnected all of my speakers but the sub and ran test tones generated on my phone. The sub out doesn't appear to do any filtering. Mystery solved.

Are you saying you could hear high frequencies coming from your sub? That would be odd.

 

[Jglr]

Are you saying you could hear high frequencies coming from your sub? That would be odd.

I couldn't hear high frequencies, as the sub has its own crossover. If the sub's crossover was set to 140 hz and I played a 140 hz (or even somewhat higher) I could hear it through the sub. I can only imagine that if this amp was filtering the signal through the sub out it would happen lower than 140hz, as there is no option to adjust the crossover point.

 

[RayDunzl]

If the sub's crossover was set to 140 hz and I played a 140 hz (or even somewhat higher) I could hear it through the sub. I can only imagine that if this amp was filtering the signal through the sub out it would happen lower than 140hz, as there is no option to adjust the crossover point.

Filters are commonly named for the -3dB point. So, 140Hz would play, only slightly subdued.

Try 1000Hz.

 

[GGroch]

Filters are commonly named for the -3dB point. So, 140Hz would play, only slightly subdued....

This is why I suggested using a powered full range speaker, not the sub itself, for this test. You could use any little Bluetooth speaker with a line/aux in. The results would be immediately obvious because no filtering.

However, at this point it would be a mostly academic exercise, as it has been correctly determined that the 9110 does not filter any outputs, and the subs speaker outs do not filter, the difference between using the speaker outs and the sub out would be very very small. Either will work fine.

Of course, whichever way to go be sure to power the sub using one of Paul McGowan's $500 audiophile AC power cables. This difference will be obvious and possibly life changing!

 

[Juhazi]

The amp here is Onkyo A-9110 which has subwoofer out line level, that A-9010 doesn't have.

 

[GGroch]

Right, corrected.

 

[Jglr]

Filters are commonly named for the -3dB point. So, 140Hz would play, only slightly subdued.

Try 1000Hz.

This is why I suggested using a powered full range speaker, not the sub itself, for this test. You could use any little Bluetooth speaker with a line/aux in. The results would be immediately obvious because no filtering.

However, at this point it would be a mostly academic exercise, as it has been correctly determined that the 9110 does not filter any outputs, and the subs speaker outs do not filter, the difference between using the speaker outs and the sub out would be very very small. Either will work fine.

Of course, whichever way to go be sure to power the sub using one of Paul McGowan's $500 audiophile AC power cables. This difference will be obvious and possibly life changing!

I connected a little amp and a speaker. The sub out is just a mono pre-out with no filtering.