Sub-woofer not operational when streaming direct from iTunes to amp

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matt17

76 posts

Master Geek

# 201760 2-Sep-2016 11:01

I recently got an active B&W sub-woofer, which is connected via cable to the amp: a brand new Denon AVR-X3200W, which is wirelessly networked.

When I stream music from my phone using Spotify to the amp (there's a direct link - it isn't going via the AppleTV), the bass speaker operates. With an iPod connected directly to the amp via USB cable, the bass speaker is operational.

I've just tried streaming music from iTunes on the Mac, directly (wirelessly) to the amp - the bass speaker isn't operational. I've check the sub-woofer's connections, power etc, volume setting - it's all set as I believe it should be. I even tried turning the sub's volume up, hand-over frequency etc : still nothing.

Any ideas why this is happening?

Matthew

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Vocus

# 1621295 2-Sep-2016 11:16

Maybe the Mac is sending a 5.1 signal but only putting audio on 2 channels?

Check it : http://www.xlr8yourmac.com/audio/OSX_DVD_DigitalSurround.html

matt17

76 posts

Master Geek

# 1621314 2-Sep-2016 11:37

Wow -that sounds complicated! Will have a read and see if it's helpful - thanks for the link.

Am playing MP3 files - maybe they can't carry a 5.1 signal..?

ubergeeknz

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Vocus

# 1621339 2-Sep-2016 12:15

matt17:

Wow -that sounds complicated! Will have a read and see if it's helpful - thanks for the link.

Am playing MP3 files - maybe they can't carry a 5.1 signal..?

No I think MP3 only goes to stereo. Somewhere along the chain it needs to be "up-mixed" to separate out the sub channel.

richms

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# 1621346 2-Sep-2016 12:23

That should be done in the bass management on the reciever automatically if you have the main speakers set to small. If it is not then I would be bitching to denon about it.

Richard rich.ms

Dunnersfella

3594 posts

Uber Geek

# 1621378 2-Sep-2016 13:04

Go into your amp menu where you can configure the speakers.

Find the section that mentions 'LFE' and change it to 'LFE + Main'.

Job done.

matt17

76 posts

Master Geek

# 1621435 2-Sep-2016 14:29

Firstly, thanks for all your help.

• I have the main speakers set to ‘large’ as they’re quite big : B&W DM602S2s -I assume that’s correct?

• I did have to change the amp’s setting to ‘LFE + Main’ : without doing that I couldn’t get any sound from the sub. Still, even with it set at ‘LFE + Main’, the sub doesn’t operate when I stream music from iTunes.

Here’s something weird though : using my iPod connected directly to the amp via USB, I just played the a file (an MP3) : the sub operates. As soon as I play that exact same file on the Mac using iTunes, and steaming direct to the amp : no sub.

So the only time the sub doesn’t work is when I stream from iMac to amp using iTunes. Spotify (streaming) and iPod via USB to amp : the sub works.

trig42

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# 1621437 2-Sep-2016 14:33

How is it getting from the Mac to the Receiver? Via an AppleTV? Has the Receiver got Airplay?

If via the ATV - does the Sub work when you play something else from it? (for example Netflix).

matt17

76 posts

Master Geek

# 1621441 2-Sep-2016 14:37

I don't believe it's using the ATV4, as the ATV is not on - although I've just looked at the TV screen and it shows the track I'm playing and 'AirPlay' - not sure if that means it's going through the ATV - or just direct from iMac to amp given they're wirelessly networked. The amp is networked, so I believe iTunes is streaming the music over the network direct to the amp (i.e. without going through the ATV). In iTunes, when I select the speakers to use, there are 3 options :

Computer

AppleTV

Denon AVR X3200W

I have the Denon checked. Selecting the ATV produces no sound - prob as it's not on. Could try it though.

I haven't tried playing Netflix content with the new sub. If it'll help diagnose the problem, I will.

richms

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# 1621447 2-Sep-2016 14:43

Seems strange that anything would come out the sub for any stereo playback if the speakers are set to large, since that means they should be full range and not need the help of the sub.

Richard rich.ms

matt17

76 posts

Master Geek

# 1621455 2-Sep-2016 14:54

Maybe I should try setting them to small? How would one normally determine if a speaker is 'small' or 'large'? It's not a physical thing is it?

richms

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# 1621456 2-Sep-2016 15:02

By what their lower cutoff is, and if they can reproduce that at the volume you want.

Most things that you can get are small, 6" drivers and ported to get some response to 80Hz at moderate volume is the best you seem to get on speakers now without spending silly money. Miss the days of 12 and 18" woofers being the norm :(

Richard rich.ms

matt17

76 posts

Master Geek

# 1621461 2-Sep-2016 15:08

I understand they're quite good speakers - the guys at AV World seemed impressed when I mentioned them, and they're British-built ones too. The website says their response is 52Hz – 20kHz ± 3dB on reference axis...means nothing to me! Should I tell the amp they're 'small'?

trig42

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# 1621462 2-Sep-2016 15:13

On the Mac, when playing back - you should see the Airplay symbol, and it will tell you what Airplay device it is playing back to (eg. Apple TV, Amp). If you change from one to the other, does it make a difference (turn the ATV on, set the Receiver to the ATV input).

Just as a test, can you play the same track back from your iPod(touch)/iPad/iPhone via the same Airplay device and get the same results? Need to find out if Airplay is causing it, or the iMac.

matt17

76 posts

Master Geek

# 1621486 2-Sep-2016 15:58

From iTunes, I can only get audio if I connect directly to the Denon device. If I select AppleTV, I get no audio at all. I tried playing a track from within the ATV interface on the TV : the sub operates when I do that. On a side note, only a sprinkling of my massive music library is visible there - no idea why.

Can't test playing a track on my iPhone, streamed to amp using AirPlay as amp is updating itself as we speak.

Tried a movie preview using the ATV : sub works.

Dunnersfella

3594 posts

Uber Geek

# 1621493 2-Sep-2016 16:19

One person supports this post

Your speakers may seem 'large', but in reality, in HiFi terms they should be considered 'small'.

True 'large' speakers are massive, both physically and financially...

Make sure you have the crossover on the back of the sub turned up all the way to 'bypass' and then control the subs crossover via the amp menu.

80Hz is a nice place to start for many people, but feel free to experiment.

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