1 (edited by DYSTmusic 2024-12-30 03:33:33)

Topic: Newbie question about AES and SPL level switch on monitors

I will be receiving an RME ADI 2/4 Pro SE in a couple of days

I have never had an iAES capable interface

My monitors (Dynaudio Core 59) are currently connected via plain old XLR to a Focusrite audio interface

However, now that I am leveling up, I want to connect the Dynaudio Core 59's via AES

What confuses me though, is how to set the Dynaudio "SPL level" switch, which provides the options of 112dB; 100dB; 96dB; or 88dB

Does anyone have a similar setup that can advise me on how to set up the AES "SPL level" between the RME and Dynaudio so as to optimize fidelity and volume

Thank you in advance

2 (edited by KaiS 2024-12-30 08:23:42)

Re: Newbie question about AES and SPL level switch on monitors

On ADI-2 set the option:

• SETUP / Options / Device Mode/DSD / Dig. Out Source: Main out
To let the Digital out signal follow the output 1/2‘s volume control and DSP.

Set:
• I/O / Output 1/2 / Settings / Ref Level: +1dBu
• I/O / Output 1/2 / Settings / Auto Ref Level: OFF

• Set Dynaudio‘s SPL Level switch to 88 dB (the lowest volume).

• Dial a volume of -6 dB on ADI-2 and play a track.

Loud enough as typical maximum loudness for you?
If not, set the SPL Level switch to louder position until your personal maximum is reached.


Now you make best use of ADI-2/4 Pro SE‘s and the Dynaudio‘s dynamic range and resolution.



Quote from Dynaudio Core 59‘s manual:

SPL Level
The SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS or -6 dB from selected analogue input sensitivity. If you work primarily at low levels, you can use a lower SPL setting to optimise the gain staging of the monitor to achieve the best results. If you work at louder levels, use the maximum 112 dB setting for the greatest volume that the monitor can provide.
Note
The 112 dB setting achieves a free field reference level of 85 dB with +20 dB of headroom at 3 meters distance.

Re: Newbie question about AES and SPL level switch on monitors

KaiS wrote:

On ADI-2 set the option:

• SETUP / Options / Device Mode/DSD / Dig. Out Source: Main out
To let the Digital out signal follow the output 1/2‘s volume control and DSP.

Set:
• I/O / Output 1/2 / Settings / Reference Level: Auto Ref Level
Although the Ref Level is for the analog output, this setting makes ADI-2 work consistent for the digital out too.

• Set Dynaudio‘s SPL Level switch to 88 dB (the lowest volume).

• Dial a volume of -6 dBr on ADI-2 and play a track.

Loud enough as typical maximum loudness for you?
If not, set the SPL Level switch to louder position until your personal maximum is reached.


Now you make best use of ADI-2/4 Pro SE‘s and the Dynaudio‘s dynamic range and resolution.



Quote from Dynaudio Core 59‘s manual:

SPL Level
The SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS or -6 dB from selected analogue input sensitivity. If you work primarily at low levels, you can use a lower SPL setting to optimise the gain staging of the monitor to achieve the best results. If you work at louder levels, use the maximum 112 dB setting for the greatest volume that the monitor can provide.
Note
The 112 dB setting achieves a free field reference level of 85 dB with +20 dB of headroom at 3 meters distance.


Thank you so very much for your reply - this really helps me out a great deal

I do have a follow-up question:  you stated to set the RME at -6dBr (is there a setting within the RME that will allow me to adjust dBr and not just dB?)

Second follow-up: does setting the RME to -6dBr and the SPL switch on the Dynaudio at 88dB mean that the loudest volume that will be output from the Dynaudio will be 88dB?

Thank you for helping a newbie

4 (edited by KaiS 2024-12-30 09:30:56)

Re: Newbie question about AES and SPL level switch on monitors

DYSTmusic wrote:

I do have a follow-up question:  you stated to set the RME at -6dBr (is there a setting within the RME that will allow me to adjust dBr and not just dB?)

Sorry, I made a mistake in my original posting (now corrected):

Set:
• I/O / Output 1/2 / Settings / Ref Level: +1dBu (any will do, as you don‘t use analog outs).
• I/O / Output 1/2 / Settings / Auto Ref Level: OFF

DYSTmusic wrote:

Second follow-up: does setting the RME to -6dBr and the SPL switch on the Dynaudio at 88dB mean that the loudest volume that will be output from the Dynaudio will be 88dB?

You still have 6 dB dial range above that for digital full scale signals, and another 6 dB of gain, (but only for quieter input signals), as ADI-2‘s volume dial range reaches up to +6 dB.

It‘s just you have to find out what max. loudness is needed in your situation and set the Dynaudios accordingly.

Re: Newbie question about AES and SPL level switch on monitors

KaiS wrote:
DYSTmusic wrote:

I do have a follow-up question:  you stated to set the RME at -6dBr (is there a setting within the RME that will allow me to adjust dBr and not just dB?)

Sorry, I made a mistake in my original posting (now corrected):

Set:
• I/O / Output 1/2 / Settings / Ref Level: +1dBu (any will do, as you don‘t use analog outs).
• I/O / Output 1/2 / Settings / Auto Ref Level: OFF

DYSTmusic wrote:

Second follow-up: does setting the RME to -6dBr and the SPL switch on the Dynaudio at 88dB mean that the loudest volume that will be output from the Dynaudio will be 88dB?

You still have 6 dB dial range above that for digital full scale signals, and another 6 dB of gain, (but only for quieter input signals), as ADI-2‘s volume dial range reaches up to +6 dB.

It‘s just you have to find out what max. loudness is needed in your situation and set the Dynaudios accordingly.


Well, the RME arrived and I just set it up as you instructed (once again, much appreciated)

I have the Dynaudio Core 59 SPL level switch set to 88

I think my eardrums will burst if I turn the volume on the RME up past -40.0dB (there is no way I can turn it up to -6.0dB)

What would you do in this situation?  Leave the Dynaudio SPL level at 88?

6 (edited by KaiS 2024-12-31 22:50:57)

Re: Newbie question about AES and SPL level switch on monitors

DYSTmusic wrote:

I have the Dynaudio Core 59 SPL level switch set to 88

I think my eardrums will burst if I turn the volume on the RME up past -40.0dB (there is no way I can turn it up to -6.0dB)

What would you do in this situation?  Leave the Dynaudio SPL level at 88?

Obviously, as to my understanding the other switch settings are even louder.

To me this seems strange, as 88 dB Peak isn’t that loud, with typical music the RMS average would be about 70 dB SPL.
(Musik has a peak to average ratio between 10-20 dB, even more with classical).

Maybe Dynaudio has an uncommon way to define their spec’s.

Re: Newbie question about AES and SPL level switch on monitors

KaiS wrote:
DYSTmusic wrote:

I have the Dynaudio Core 59 SPL level switch set to 88

I think my eardrums will burst if I turn the volume on the RME up past -40.0dB (there is no way I can turn it up to -6.0dB)

What would you do in this situation?  Leave the Dynaudio SPL level at 88?

Obviously, as to my understanding the other switch settings are even louder.

To me this seems strange, as 88 dB Peak isn’t that loud, with typical music the RMS average would be about 70 dB SPL.
(Musik has a peak to average ratio between 10-20 dB, even more with classical).

Maybe Dynaudio has an uncommon way to define their spec’s.

Thank you

Doesn't the AES bit change depending on SPL level?  Meaning, the RME could lower the bit rate if the SPL level is not configured properly?

8 (edited by KaiS 2024-12-31 22:52:54)

Re: Newbie question about AES and SPL level switch on monitors

AES and SPDIF transfer 24 bits.
Lowering the level by 40 dB means 7 bits less.

The remaining 17 bit or 102 dB are still a bit better than CD’s full dynamic range and resolution.
IMO OK, although not quite like intended.


Maybe Dynaudio has an uncommon way to define their spec’s:

SPL Level
The SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS or -6 dB from selected analogue input sensitivity. If you work primarily at low levels, you can use a lower SPL setting to optimise the gain staging of the monitor to achieve the best results. If you work at louder levels, use the maximum 112 dB setting for the greatest volume that the monitor can provide.
Note
The 112 dB setting achieves a free field reference level of 85 dB with +20 dB of headroom at 3 meters distance.

This might be the key: “20 dB headroom” might say in fact the sound is 20 dB louder than set - strange and counterintuitive, not what the sentence above says:

SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS

9 (edited by DYSTmusic 2024-12-31 23:19:22)

Re: Newbie question about AES and SPL level switch on monitors

KaiS wrote:

AES and SPDIF transfer 24 bits.
Lowering the level by 40 dB means 7 bits less.

The remaining 17 bit or 102 dB are still a bit better than CD’s full dynamic range and resolution.
IMO OK, although not quite like intended.


Maybe Dynaudio has an uncommon way to define their spec’s:

SPL Level
The SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS or -6 dB from selected analogue input sensitivity. If you work primarily at low levels, you can use a lower SPL setting to optimise the gain staging of the monitor to achieve the best results. If you work at louder levels, use the maximum 112 dB setting for the greatest volume that the monitor can provide.
Note
The 112 dB setting achieves a free field reference level of 85 dB with +20 dB of headroom at 3 meters distance.

This might be the key: “20 dB headroom” might say in fact the sound is 20 dB louder than set - strange and counterintuitive, not what the sentence above says:

SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS


Hmm, perhaps I should forget AES and go analog?
Or, if I am only going to get 17 bits out of the RME, have I wasted my money on it?

10 (edited by KaiS 2025-01-01 00:55:31)

Re: Newbie question about AES and SPL level switch on monitors

I guess you got ADI-2 for it’s features on the whole, not just as AES interface.
Analog is always an option, could indeed deliver a little more resolution, depending on the AD-converter inside Dynaudio.

It would allow Dynaudio to run on a higher sample rate, like this:

High end DA (ADI-2) on music track’s native sample rate -> possibly lower AD (Dynaudio), but running on high sample rate -> speaker’s DSP’s beneficial running on higher SR’s.

Specially digital filter, e.g. speaker crossovers, like higher sample rates, they are working more precise.


You’re in the perfect situation that you can compare the sound, as you now got everything on hand.
Only a bit hard to set the same audition level, which is essential for a valid judgement on sound.

Maybe an inquiry at Dynaudio about what they think about the digital level situation, which does not really correlate with their manual’s claims.


BTW:
There’s a free Dynaudio measurement app for iPhone (a relabeled version of AudioTools from Andrew Smith).
https://apps.apple.com/de/app/dynaudio- … 1082994691

Maybe you can check your level with it’s SPL Meter.

11 (edited by DYSTmusic 2025-01-01 02:16:27)

Re: Newbie question about AES and SPL level switch on monitors

KaiS wrote:

I guess you got ADI-2 for it’s features on the whole, not just as AES interface.
Analog is always an option, could indeed deliver a little more resolution, depending on the AD-converter inside Dynaudio.

It would allow Dynaudio to run on a higher sample rate, like this:

High end DA (ADI-2) on music track’s native sample rate -> possibly lower AD (Dynaudio), but running on high sample rate -> speaker’s DSP’s beneficial running on higher SR’s.

Specially digital filter, e.g. speaker crossovers, like higher sample rates, they are working more precise.


You’re in the perfect situation that you can compare the sound, as you now got everything on hand.
Only a bit hard to set the same audition level, which is essential for a valid judgement on sound.

Maybe an inquiry at Dynaudio about what they think about the digital level situation, which does not really correlate with their manual’s claims.


BTW:
There’s a free Dynaudio measurement app for iPhone (a relabeled version of AudioTools from Andrew Smith).
https://apps.apple.com/de/app/dynaudio- … 1082994691

Maybe you can check your level with it’s SPL Meter.


Once again, thank you for your reply

Dynaudio's Core 59 page says the following:

https://i.imgur.com/AZ9LQAE.png


It's incredible to me that people can listen at -6dB (but, this is based upon the experience I posted above that -40dB is loud)


I could order an SPL meter from Amazon (probably more accurate than the iPhone internal mic)


As regards the statement you quoted from Dynaudio:

The SPL Level setting determines the volume the monitors will achieve for an input level of -6 dBFS or -6 dB from selected analogue input sensitivity. If you work primarily at low levels, you can use a lower SPL setting to optimise the gain staging of the monitor to achieve the best results. If you work at louder levels, use the maximum 112 dB setting for the greatest volume that the monitor can provide.

Since I am using AES, wouldn't the measurement be -6dBFS, and not -6dB?  Would that change things?

12 (edited by KaiS 2025-01-01 10:59:37)

Re: Newbie question about AES and SPL level switch on monitors

DYSTmusic wrote:

It's incredible to me that people can listen at -6dB (but, this is based upon the experience I posted above that -40dB is loud)

Dynaudio Monitors always had been the choice of people producing heavy metal.

DYSTmusic wrote:

I could order an SPL meter from Amazon (probably more accurate than the iPhone internal mic)

I can’t comment on any el-cheapo meter other that it’s not trustworthy.

I’m using AudioTools on various iDevices by myself, have professional Sound Level calibrators (accurate to 1/10 dB) and Bruel&Kjaer Sould Level Meters.

On all my iDevices AudioTools supplied calibration is accurate within +/-1 dB, that’s very good for acoustic measurements.

As mentioned, the Dynaudio app is relabeled from AudioTools.
It’s free, so it’s limited to dBA weighted measurements (low frequencies filtered out), but that’s OK, as low f’s spoil the result due to room modes.

Still, I withdraw my recommendation, as on various iDevices I could not switch on it‘s Pink Noise generator, making usage too complicated.

Instead I suggest to I suggest FFT from Andrew Smith, out of the Audio Tools suite, for iDevice.
https://apps.apple.com/de/app/fft/id298840058

For just 12 bucks it turns an iDevice into a calibrated, full fledged measurement system, and has Signal Generator and Sound Level Meter built in.

What you need is the Apple CCK - Camera Connection Kit to connect the iDevice to ADI-2, or just an USB-C to USB-B cable if you have an USB-C equipped iPad.


You can install FFT on multiple iDevices, use one as stationary generator, iDevice digitally connected to ADI-2, and the 2nd as meter/analyzer.
Or, just record some minutes of SMPTE Pink Noise on your DAW from the iDevice digitally connected (using the Apple CCK - Camera Connection Kit or fitting cable).


• On FFT set:
- Settings / General / Global Audio Settings: Use SMPTE Pink Noise (might be default)
- Start FFT, Wrench Tool, set “A-Wtd SPL”
- FFT-main screen, ~ -sign (Generator): 0 dBFS, Pink, On.

• Play the Noise with all computer volume controls set to 0 dB if you are using a DAW (to achieve a defined reference Level).

• Set ADI-2’s Volume to -6 dB, this is Dynaudio’s reference, so we meet it.

• Send the Pink Noise to one speaker only, from 3 meter distance, that again Dynaudio’s reference.

• On the FFT screen, press the Play-sign to start the measurement.
The top right figure shows the SPL.
Add 22 dB correction factor to the reading.

We need the correction, because we use Pink Noise, not steady state sine waves for the measurement (which are not usable for a in-room measurement).


The result should reflect Dynaudio’s SPL-switch settings, e.g. 88 dB in the lowest setting.

So, you should read 66 dB on the FFT screen figure up right, add 22 dB = 88 dB.


DYSTmusic wrote:

Since I am using AES, wouldn't the measurement be -6dBFS, and not -6dB?  Would that change things?

That’s the same if you use a full scale 0 dBFS signal as reference, like I did for my prescription above.


This is where the 22 dB correction factor comes from:

SMPTE Pink Noise, RMS A-weighted, relative to a full scale 1 kHz sine wave is -22 dB in level.