Can I delay the left or right channel by a few milliseconds?

[amireldor]

I want to delay the only left channel by a few milliseconds.

My speaker setup requires me to put the right speaker about 1.5m further than the left speaker is. This way, the sound coming from the left speaker reaches the ear faster than sound from right one. This causes me great woes and headache.

If I delay the left signal, then the sound coming from the left speaker will arrive exactly when the sound from the right speaker reaches my ear.

How do I approach this?

 

[wasnotwas]

Your estimation of milliseconds is correct. The speed of sound is 343 m/s, so 1.5 m would be 4 milliseconds of delay. I'm surprised your ear/brain can detect 4ms. Sometimes, when a movie I am watching has out of sync sound I alter the sync (on VLC player) in 50 ms quanta. I find I can't see any lipsync difference below 100ms, whilst > 250ms 'out' is unwatchable, for me anyway. That said, I've read that a skilled cinema lipsync expert can make adjustments of fractions one frame (about 40ms). I know this is a different scenario to what you are describing, but I find your perception of 4ms interesting.

What about wall reflections - are you listening to your hifi in an anechoic chamber ?

The subject of imperceptible audio differences usually triggers jokes about Russ Andrews, and their $1000 phono leads, mains cables etc.

audio interconnects, hdmi and Kimber speaker cable from Russ Andrews for your hifi and home cinema

Sorry for being of no help - just my $0.02

 

[LMiller7]

I don't think you can do that without external hardware, of which I know nothing about.

 

[carwiz]

The Realtek Audio Manager has a room correction (spacing) option. At least mine does. However, it's only available when using 5.1 or 7.1 sound systems. Check it out.

Added pic

 

[amireldor]

I'm surprised your ear/brain can detect 4ms. Sometimes, when a movie I am watching has out of sync sound I alter the sync (on VLC player) in 50 ms quanta. I find I can't see any lipsync difference below 100ms, whilst > 250ms 'out' is unwatchable, for me anyway.

It's not the delay effect that I feel (i.e. a 'stutter' in the audio), it's more related to a "phasing" effect. Imaging two sine wave signals at the same frequency and amplitude. Summed up, their volume increase; but if one is a bit 'delayed' from the other then you start getting cancellations and boosts to the overall signal which distorts the sound and that's my case. This brings me to:

The Realtek Audio Manager has a room correction (spacing) option. At least mine does. However, it's only available when using 5.1 or 7.1 sound systems. Check it out.

This is exactly what I need and thought about, but alas! I do not have a 5.1+ output setting.
Maybe I can at least find a media player that supports this feature. This way I can solve phasing for hearing music or watching stuff.

 

[wasnotwas]

I found this interesting article on sound delay as used by p.a. crews to delay the signal feeding the relay speakers at the back of a large venue (eg rock gigs at a football stadium). The writer says that a typical value for a large arena of 1/6 sec makes music muddy and speech difficult to understand.

Sound Delay Explained, SXS Events

I also found this commercial DSP that is calibrated in metres, feet or ms

Behringer: SHARK DSP110

fascinating topic

 

[amireldor]

Yes, I realized I have the problem at my home while studying for my sound technician certificate. We had a course about live shows amplification. It is a fascinating subject!

Regarding the Behringer, yes, I came across that unit last couple of days while searching for a solution. It is rather cheap (concerning pro audio equipment), but I'd rather not buy one for my particular setup ATM. Also, similar to carwiz's advice, home cinema receivers usually have this delay compensation function for individual speakers.

 

[carwiz]

As the Realtek driver suggest, in true stereo, left and right output shouldn't make much difference. If you are hearing a phase shift then perhaps the source is not true stereo but mono to two speakers channels. My speakers are oriented on my left as I face the PC screen but left and right as I face the keyboard. If there is phasing, I can't perceive it in stereo mode because the sound from each speaker is different. Perhaps you need to invest in a better sound card that allows the adjustments you need.

Or you could just wear headphones.

 

[society misfit]

Ideally you will want to balance your 2 speakers the same distance from your listening position. However, I know this is not always possible. Foobar2000 (for music only) has a component that will allow you to add delay to one or all your channels. You will need to install Foobar first (personal favorite of all music players), then install the component found here. Channel Mixer (foo_channel_mixer) - Hydrogenaudio Forums


What’s great about Foobar is that it and all of its components (and there are many) is free!

 

[Layback Bear]

You can change the direction you point speaker and make a m/s change in travel time to your ears.
The quality of each speaker connection can change m/s.
The variation of each speaker can change m/s.
The length of each speaker wire can change m/s.

Remember a m/s =1/1000th of a second.
The human ear will never hear a m/s or several m/s difference.

 

[society misfit]

Changing the direction of the speaker (ie; off axis) will actually do more harm than good. One will lose detail and increase or decrease wall reflections depending on how and where it has been pointed.

Sound level will decrease by 6db for every double the distance the listener is from the source. So, if the OP was 1.5m from the right speaker, his left which is now 3m away will be 6db down requiring 4x the power to achieve the same volume as the right. This is just a very simplified example and does not take into effect reflections from the walls, ceilings and floor which will have a greater impact than just changing the delay (changing the delay does not rectify reflections – just makes them nonlinear).

Amireldor; I suggested Foobar because it’s free to try and it’s fun to toy with. It’s a pretty powerful media player if you can get around the whole DIY feel of it. But if you are serious enough about sound reproduction, adding delay will only correct the time in which direct sound will hit your ears. It will not correct the differences between amplitude or reflective sounds. Having your speakers of equal distance from both their reflective boundaries and your ears will create a predictable environment in which you can work with using acoustics and or DSP equalization.

 

[wasnotwas]

Remember a m/s =1/1000th of a second.
The human ear will never hear a m/s or several m/s difference.

That's what I was alluding to when I mentioned the delay problem at rock gigs in football stadiums. Any delay due to speakers at home being 1.5 metres apart is imaginary IMHO.

 

[society misfit]

Actually, the human auditory system can detect delays as low as ~0.6 milliseconds. This is how we localize sounds. A single sound source that is not 0°[FONT=&quot] or [/FONT]180° in front or behind the head will produce a delay to the furthest ear which is easily detectable. Of course amplitude and frequency will also play a part in this but to say the human ear cannot detect a millisecond of delay is not true. [FONT=&quot][/FONT]

 

[carwiz]

Those of us with tinnitus welcome some deviation from the hissing and 10-pound crickets in either or both ears.

 

[Layback Bear]

Those of us with tinnitus welcome some deviation from the hissing and 10-pound crickets in either or both ears.

You had to remind me and now it's louder.

 

[amireldor]

Thank you for all the replies.