Test audio for 2.1 systems ? To balance the sub in particular.

[5ynth3t1k]

Hiya.

I'm looking for a some test sound media OR dedicated sound files that I can use to test and balance my 2.1 system by ear.
( no I'm not interested in discussing why I might want to do this... sorry ! )

So the idea that is in my tiny brain is this:

Here is some noise that your top/mid speakers should be able to reproduce and it should not be in your sub.
Here is some noise that your sub speaker should be able to reproduce and it should not be in in your top/mid speakers.
Soooo, you can tweak things to get the 2.1 system sounding about right.
( I guess the sub top end cut off and volume being set is the thing here really)


The most obvious thing: no two systems are alike. ( they will have different "cross over" points from top/mid to sub... etc etc )
BUT the idea is to get it roughly in the ball park without resorting to special mic's and software etc.

So right now did I dial in the sub by ear. It's not ideal.

OR

If I blast white noise through the whole system and then tune the sub so that it "sounds right" is this all I need to do ?

Remember this is quick and dirty. Not slow and fancy. ( If you wish to extol the virtues of Slow and Fancy ... please no! )

Looking forwards to suggestions !

Cheers. :- )

 

[Vincent Kars]

Here is some noise that your sub speaker should be able to reproduce and it should not be in in your top/mid speakers.

Really?
A lot of setups don't allow for offloading the bass from the main speakers. Most of the time it is an amp with a sub out passing the full signal to the main speakers.
Do you have an option to high pass the signal to your main speakers?

 

[antcollinet]

Are you able to use REW - you can generate all sorts of test signals with that, including band limited pink or white noise. So if your sub bandwidth is (for example) 30Hz to 150Hz, you could have pink noise limited to that bandwidth.

Alternatively - use an online tone generator to create any specific sine wave frequency.

 

[DVDdoug]

Audacity can also generate tones, white noise, and pink noise.

So right now did I dial in the sub by ear. It's not ideal.

That's not so bad! It's not unusual to make some final tweaks by-ear after measuring and calibrating. Plus, the subwoofer and room modes are not flat so matching the SPL just and below the crossover frequency may not sound right.

And if you are not listening "loud" you might want to boost the bass. The Equal Loudness Curves (a characteristic of human hearing) make it sound like you've turned-down the bass when you've only turned down the volume.

If you are doing measurements you should be using a calibrated measurement mic (about $100 USD).

 

[5ynth3t1k]

Really?
A lot of setups don't allow for offloading the bass from the main speakers. Most of the time it is an amp with a sub out passing the full signal to the main speakers.
Do you have an option to high pass the signal to your main speakers?

The main speakers by the virtue of not being able to reproduce sub bass etc will obviously not be reproducing the sub bass. The sub bass unit by virtue of .. I think you get the drill here.

It's all pretty simple and low tech. the hard part is setting the high cut on the Sub and the Volume.

Thanks.

 

[5ynth3t1k]

Are you able to use REW - you can generate all sorts of test signals with that, including band limited pink or white noise. So if your sub bandwidth is (for example) 30Hz to 150Hz, you could have pink noise limited to that bandwidth.

Alternatively - use an online tone generator to create any specific sine wave frequency.

sure, testing for the sub cut off is one thing, testing for the "balance" between the main speakers and the sub unit is another, well this is how it strikes me.

there must be some kind of fool proof "by ear" method.

Thanks!

 

[5ynth3t1k]

Audacity can also generate tones, white noise, and pink noise.


That's not so bad! It's not unusual to make some final tweaks by-ear after measuring and calibrating. Plus, the subwoofer and room modes are not flat so matching the SPL just and below the crossover frequency may not sound right.

And if you are not listening "loud" you might want to boost the bass. The Equal Loudness Curves (a characteristic of human hearing) make it sound like you've turned-down the bass when you've only turned down the volume.

If you are doing measurements you should be using a calibrated measurement mic (about $100 USD).

ah yes, see we are slowly doing "technical creep" ha ha.

So we do the UNIT volume and UNIT Distance from the speakers. ( unit vol = 11 and unit dist = my nice vintage swivel chair )

and no I am not doing measurements. I'm doing all "by ear". ( Your ears are your filters ! This is deeply recursive joke..)

Thanks!

 

[DVDdoug]

The main speakers by the virtue of not being able to reproduce sub bass etc will obviously not be reproducing the sub bass.

Without a crossover you won't be able to "match" the high-pass and low-pass where they are both operating.

If the outputs match, the crossover makes sure they overlap by reducing the output in half at the crossover frequency and properly blending above and below.

A crossover also prevents the main speakers from trying to reproduce the bass and distorting. (More of a problem when "pushing" the speakers and listening loud.)

 

[Svensson]

Hi mate, I have a "meat and potatoes" 2.1 system without ability to set cross over using an amp or software. My sub has a built in FR knob. I wanted to set the subs dial so it picked up where the speakers FR fell away. Because of room gain and speaker placement, the published measured values for speakers are OK, but not reliable.

What I did (open to scrutiny and thoughts)

1. Installed an SPL meter app and a tone generator on my phone. Depending upon how you play music through your system, you'll find test tones to play and listen to.
2. Disconnect sub: Play test tones from 80Hz down in 5-10Hz increments to 40Hz though my speakers. Note SPL values if you use an app. If using ears give a score out of 10, to see where the SPL fell away in my room.
3. Disconnected speaker, repeat through your sub with FR know set to about 100Hz.
4. Pen and paper is king and I worked out where to set the sub
5. Then double check: Both speakers and sub connected. Repeat playing test tones from 80Hz downwards using the SPL meter on the phone or your ears to give a score. Fine tweak the subs FR knob.
6. Play uncorrelated pink noise at a good SPL and use the FR app on your phone (just make sure there are no other noise intrusions like a vacuum cleaner, washing machine, kids or pets to play too. The average for the pink noise is helpful but only really between say 1500Hz and maybe 30-40Hz

It isn't pretty and liable to all sorts of scrutiny, but close enough.