Speaker Test Tones: AVR Built-In or External Test Disc?

[RegularStereoGuy]

Speaker Test Tones: AVR Built-In or External Test Disc?

Anyone with a home theater receiver, Dolby Pro Logic, Dolby Digital, DTS or other, is probably aware of the receiver's ability to play test tones (white or pink noise) through each speaker, to help balance speaker levels in a home theater setup.

My question is, as per the thread title, which ones do you find, or feel, are more accurate and trustworthy to use, to even out all speaker levels?

 

[wwenze]

If you are using the AVR's own auto correction system, then you have to use the AVR's built-in sound and the AVR's mic

If you are using an external correction system, you have to 1) Ideally, connect your computer to the input of the AVR, or 2) If you can't do 1. then burn a test disc, and the program will search for a marker sound at the start of the recording.

If your question is which is better, then, if your AVR has a Dirac or something that is better than your external correction, then you should use the AVR.

Level matching is just the tip of the iceberg, because the frequency response of the speaker also changes with your room positioning. Without a mic, you can hear a difference, but you can only set to "too loud" or "too soft" if you only adjust the volume because different frequencies have different loudness.

 

[Philbo King]

Choices, best to worst:
- REW + measurement mic, Dirac, or similar.
- Built-in AVR correction
- Listening to test tones and trying to EQ by ear

 

[RegularStereoGuy]

Thanks for your responses and suggestions!

Some clarification:

This receiver is an older model, no mic connections or auto-cal to speak of. I'm using a tripod-mounted sound level meter, A-weighted, positioned approximately in the middle of my listening/viewing space.

Adjustments for center and surround channel are in multiples of '2', from -20 to +20(dB, I'm assuming). I adjust both center and surrounds until the meter indicates Zero with a sensitivity setting of 80dB for all speakers.

The reason I'm asking this question is because I get different setting results when using external test noise vs the built-in noise.

 

[RegularStereoGuy]

Man I must ask some really off the wall questions up in here..!

 

[90sNintendoKid]

Would you please provide more details on the external test tones being used? Might I suggest you investigate using REW and a measurement mic like the Minidsp UMIK1 or UMIK2?

I use the Spatial Audio Calibration Toolkit and the level matching tones (band limited pink noise) for level matching.

 

[RegularStereoGuy]

Would you please provide more details on the external test tones being used? Might I suggest you investigate using REW and a measurement mic like the Minidsp UMIK1 or UMIK2?

I use the Spatial Audio Calibration Toolkit and the level matching tones (band limited pink noise) for level matching.

They're on any audio test CD or DVD, and consist of a couple seconds of pink or white noise played through each channel.

My receiver is probably older than most participants in this forum: a 1995 JVC 515 Pro Logic surround receiver, with no provisions to connect a microphone. For reference purposes only, Bill Clinton was U.S. president when this receiver was on store shelves.

 

[Ellebob]

For just setting levels any SPL meter will do as you only need relative levels beween channels. A phone SPL meter is fine. Set the SPL meter to C weighting and slow response not A weighting. A weighting does not read low frequencies well and you would add too much bass when setting the subwoofer.
The receiver test tones should be fine and you should be using pink noise if using a disc and that is what the receiver will use. For relative SPL measurements it probably doesn't make a difference but if measuring frequency response then there is a difference between pink noise and white noise. In theory there should be no difference in whether you use the disc or receiver's tones. The volume level might be different but as long as they are the same between speakers is what matters.

 

[kemmler3D]

My receiver is probably older than most participants in this forum: a 1995 JVC 515 Pro Logic surround receiver, with no provisions to connect a microphone. For reference purposes only, Bill Clinton was U.S. president when this receiver was on store shelves.

You must have this forum mistaken for Reddit, I'm 40 and I think I'm considered a whippersnapper around here.

@Ellebob has good advice here.

If you are just setting relative levels (i.e. you don't need exact / correct SPL) then I would agree a phone app is fine.

For what it's worth when I do test tones I often use this via Bluetooth on my phone: https://www.szynalski.com/tone-generator/ or this for PN: https://29a.ch/noise-generator/ - convenient as long as you have a BT receiver in the mix somewhere.

I get different setting results when using external test noise vs the built-in noise.

How different are the results? Are you putting the mic in the exact same spot each time? Do you hear any difference in the test signals?

 

[RegularStereoGuy]

You must have this forum mistaken for Reddit, I'm 40 and I think I'm considered a whippersnapper around here.

@Ellebob has good advice here.

If you are just setting relative levels (i.e. you don't need exact / correct SPL) then I would agree a phone app is fine.

For what it's worth when I do test tones I often use this via Bluetooth on my phone: https://www.szynalski.com/tone-generator/ or this for PN: https://29a.ch/noise-generator/ - convenient as long as you have a BT receiver in the mix somewhere.


How different are the results? Are you putting the mic in the exact same spot each time? Do you hear any difference in the test signals?

I have a SPL meter, might as well use it.

The SPL meter stays in the same location, regardless of the source of channel ID noise I play through the receiver.

The built-in noise sequence is L > C > R> Surr(mono) and repeats until on presses the Test button again to turn it off. The noise does play through the sub, but the sequence does not include playing noise exclusively through it.

Playing an external noise sequence, the difference between the levels for Center and Surround are less(leave Center at 0, Surrounds at +2) than they are when using the receiever's built-in noise sequence (Center +4, Surr +6).

To try to frame my concern as succinctly as possible:

Which of those results: Using the receiver built-in, or external source noise sequence, would be considered the more accurate?

I'm sorry this is such an off-the-wall topic!

 

[Ellebob]

It sounds like the receiver and disc are identical. Either way there is a 2db difference between center and surround. Are they different from the front speakers?

Use volume knob and play the tone through the left speaker. Set the volume so that the SPL meter reads 70db. The left speaker should be at 0 because you adjusted the volume with the main volume knob and not the +/- settings. Keep the receiver at that volume. Then play the test tone through the other speakers/sub and adjust with +/- settings.

 

[kemmler3D]

I have a SPL meter, might as well use it.

Sure, you might want to try a phone app just as a secondary / backstop kind of check.

The SPL meter stays in the same location, regardless of the source of channel ID noise I play through the receiver.

The built-in noise sequence is L > C > R> Surr(mono) and repeats until on presses the Test button again to turn it off. The noise does play through the sub, but the sequence does not include playing noise exclusively through it.

Playing an external noise sequence, the difference between the levels for Center and Surround are less(leave Center at 0, Surrounds at +2) than they are when using the receiever's built-in noise sequence (Center +4, Surr +6).

Looks like the relative difference is +2 in either case, so it's probably just a matter of one of the noise sources being louder.

To try to frame my concern as succinctly as possible:

Which of those results: Using the receiver built-in, or external source noise sequence, would be considered the more accurate?

I'm sorry this is such an off-the-wall topic!

The noise source shouldn't be an issue for level-setting. As long as you feed the same thing to each speaker, the quality or type of the noise signal is not going to change your results much. The accuracy comes from the SPL meter / mic.

A UMIK-1 with REW will give you a reading within a fraction of a dB and comes calibrated from the factory. A phone app will tend to give a fraction of a dB too, although it won't be calibrated, so the accuracy relative to overall SPL and dBA, dBC, dBZ weightings is going to be questionable, but as far as relative gain settings, still useful.

All that said, setting it within 2dB using your meter is probably fine, and as long as you are consistently getting the same relative results between each speaker (i.e. the net difference is the same regardless of the noise source) I don't think you have anything to worry about. The same applies if you are trying for a reference SPL - your results are determined by the meter.

 

[RegularStereoGuy]

Sure, you might want to try a phone app just as a secondary / backstop kind of check.

Looks like the relative difference is +2 in either case, so it's probably just a matter of one of the noise sources being louder.

The noise source shouldn't be an issue for level-setting. As long as you feed the same thing to each speaker, the quality or type of the noise signal is not going to change your results much. The accuracy comes from the SPL meter / mic.

A UMIK-1 with REW will give you a reading within a fraction of a dB and comes calibrated from the factory. A phone app will tend to give a fraction of a dB too, although it won't be calibrated, so the accuracy relative to overall SPL and dBA, dBC, dBZ weightings is going to be questionable, but as far as relative gain settings, still useful.

All that said, setting it within 2dB using your meter is probably fine, and as long as you are consistently getting the same relative results between each speaker (i.e. the net difference is the same regardless of the noise source) I don't think you have anything to worry about. The same applies if you are trying for a reference SPL - your results are determined by the meter.

I guess that's why the receivers center and surround level adjustments are in twos: +2, +4, -2, -4, and so on.

As for the phone as SPL, nahh, I use the phone to make phone calls.

 

[dualazmak]

Super Audio Check CD 48DG3 by CBS/Sony (1983) is/was mainly designed for testing 2-channel stereo setup, but it is also very much useful for almost all purposes of check and tuning of our audio system. If you would be interested, please find my post here #651 on my project thread. The test CD is consists of strictly prepared high-precision tracks.

The English (translation by myself) PDF of the booklet (liner notes) is attached herewith for your reference. If you would be seriously interested in hearing and/or utilizing any of the tracks in the "Super Audio Check CD 48DG3 by CBS/Sony (1983)", please simply PM me writing your wish.