Are SPL meters and phone apps accurate for setting subwoofer levels?

[Sliced Bread]

Are SPL meters and phone apps accurate for setting subwoofer levels?

Most of us on here already know the old traditional way of setting up a subwoofer for music (turning it right down, then turning it up until you can only just hear it) and this works a treat for music, but what method do you use when setting the subwoofer level in a home theatre setting.

I recently replaced by sub so I’m going back through the exercise of fine tuning it. I began by using an SPL meter so it is the same volume as the other channels, but this just feels too hot for me. Are these things accurate when it comes to bass?

It’s very loud and exciting for things like Jurrasic World & Last Jedi, but it becomes a little too much with Netflix programms like Luke Cage. I'm just trying to figure out if the subwoofer should indeed be turned down, or if some of the material I'm watching has just been mixed with too much bass for my tastes.

Last night I dropped the level by about 2 db and it all came together much better while watching Luke Cage, though I still need to try this with Jurrasic World & Last Jedi to ensure its now not too tame.

So how do you guys set your levels for films?

 

[MajorFubar]

The microphone on a typical mobile phone won't necessarily be flat across its frequency range, so no, you're expecting too much from something not intended for critical SPL measurement. SPL apps on phones are at best useful for showing the average noise level across the full frequency range, not certain bands of it, and at worst are just a novelty.

I'd expect a genuine handheld SPL meter to be more accurate though. But even that said, it too might not necessarily be flat at frequency extremes depending on what it was designed for, hence why you feel the bass setting it's recommended is too hot.

 

[Sliced Bread]

The microphone on a typical mobile phone won't necessarily be flat across its frequency range, so no, you're expecting too much from something not intended for critical SPL measurement. SPL apps on phones are at best useful for showing the average noise level across the full frequency range, not certain bands of it, and at worst are just a novelty.

I'd expect a genuine handheld SPL meter to be more accurate though. But even that said, it too might not necessarily be flat at frequency extremes depending on what it was designed for, hence why you feel the bass setting it's recommended is too hot.

Thanks Major, that's what I was suspecting.

I have an SPL meter, though it was pretty cheap and is about 15 years old. It works fine for the main channels, but it too seems to struggle with the sub. Even with the "C" weighting set on the meter, the needle jumps all over the place when presented with the subwoofers white noise.

Maybe I need to source a better quality meter.

 

[MajorFubar]

I'd just leave it at the setting you instinctively feels sounds right, that being -2dB down on what your meter is telling you. Many of us want decisions like this to be vindicated by a piece of hardware with no personal bias which can 'hear' better than us, but the hardware doesn't have to live with the sound afterwards. Hypothetical question: if an expensive meter told you your current setting was +/-2dB adrift from what sounds right to you, would you obey the meter and put up with a sound you don't like, or would you ignore it and use a setting which sounds right? Presumably the latter, so save your money. If for some films you prefer it boosted by 2dB or dropped by 2dB, you go for it and embrace that liberty. You wasn't in the film's PP suite when the audio engineer was shuffling the fader around on the LFE channel to get the sound that pleased only his ears, so it's yet another example of aiming for an unknown goal. Just enjoy!

 

[Blacksabbath25]

You will only get a rough idea with a SPL meter for setting up a sub up for its levals and that is using a proper SPL meter which is better then a app testing but you will get a rough guide which is all you need to do .

 

[Sliced Bread]

...but the hardware doesn't have to live with the sound afterwards.

This bit made me chuckle.

You've got a point

 

[Sliced Bread]

You will only get a rough idea with a SPL meter for setting up a sub up for its levals and that is using a proper SPL meter which is better then a app testing but you will get a rough guide which is all you need to do .

If that's the case, then I'll abandon the idea. I just looked at the prices of some more capable SPL meters and they run into hundreds. Totally not worth it...especially if it's not going to be 100% accurate.

I'll just leave it at the current level for a while as I can always increase it if I decide it's not quite right.

I'd like to use REW, just out of curiosity, but I just don't have the time to learn how to use it.

Thanks everyone.

 

[Blacksabbath25]

You will only get a rough idea with a SPL meter for setting up a sub up for its levals and that is using a proper SPL meter which is better then a app testing but you will get a rough guide which is all you need to do .

If that's the case, then I'll abandon the idea. I just looked at the prices of some more capable SPL meters and they run into hundreds. Totally not worth it...especially if it's not going to be 100% accurate.

I'll just leave it at the current level for a while as I can always increase it if I decide it's not quite right.

I'd like to use REW, just out of curiosity, but I just don't have the time to learn how to use it.

Thanks everyone.

A proper SPL meter is accurate with main levels in a home cinema but the subwoofer level is different as it’s very low down sound that’s outputting as a rumble .

But you can buy a SPL for under a £100 new on eBay which works just as well as the very expensive ones so do not be put off as I think they are a important tool to use with home cinema even though the Av has its own calibration software I still use a SPL meter .

 

[Sliced Bread]

You will only get a rough idea with a SPL meter for setting up a sub up for its levals and that is using a proper SPL meter which is better then a app testing but you will get a rough guide which is all you need to do .

If that's the case, then I'll abandon the idea. I just looked at the prices of some more capable SPL meters and they run into hundreds. Totally not worth it...especially if it's not going to be 100% accurate.

I'll just leave it at the current level for a while as I can always increase it if I decide it's not quite right.

I'd like to use REW, just out of curiosity, but I just don't have the time to learn how to use it.

Thanks everyone.

A proper SPL meter is accurate with main levels in a home cinema but the subwoofer level is different as it’s very low down sound that’s outputting as a rumble .

But you can buy a SPL for under a £100 new on eBay which works just as well as the very expensive ones so do not be put off as I think they are a important tool to use with home cinema even though the Av has its own calibration software I still use a SPL meter .

Thanks.

If it is just for the main channels, then I have that covered as I have a cheap one from years back. It’s just it cannot cope with thre sub level at all.

 

[duaplex]

Avoid apps they are not accurate in comparision to a good mic and SPL setup.

 

[Sliced Bread]

Avoid apps they are not accurate in comparision to a good mic and SPL setup.

Thanks Duaplex.