Topic: ADI-2 FS static noise/crackling noise

I have the RME ADI-2 FS. It is mainly used in connection with a streamer (optical input), but occasionally is also connected to a CD transport (coaxial) and a Macbook (USB). Some months ago it started generating a crackling/static-like noise when the volume level was over +4dBr. During the last months this noise is progressively going lower and lower and now it appears at -3.0dBr. It is not constant and there is no rule when it will be produced. It is produced in all three inputs, although at the optical input it appears in lower volumes. The static/crackling noise is generated at peaks of the music, regardless of high, mid or low frequencies. When the volume is decreased by approximately 1-2 dBr it disappears.

Through trial and error I have excluded the problem being connected with the interconnects, the amplifier, the speaker cables, the specific wall socket. The wiring in the house is in excellent condition and relatively new (10 years) and I have no other issue with other audio/video appliances. The firmware has been updated to the latest version (currently 35). 

Note: The issue I have seems to be different from the issue of the thread https://forum.rme-audio.de/viewtopic.php?id=31463 which has similar title

2 (edited by KaiS 2021-05-27 16:45:56)

Re: ADI-2 FS static noise/crackling noise

Are you really using -3 dbr (watch out for the r)?

This is close to full output and that’s quite a lot of level / voltage.

Not every integrated amplifier can handle such hot signals, some are overdriven at their input.
The kind of “noise”-sound you describe points to overdrive of electronic input switches of typical integrated amplifiers.

Bring down ADI-2 DAC (?) Pro (?) a bit and dial up the amplifier’s volume control to get the same listening level.

Re: ADI-2 FS static noise/crackling noise

I am using for months 0 dB as the default level at the two devices in the chain (streamer and ADI-2 DAC) and regulating the volume through the integrated amplifier but noticed quite recently that the output in the DAC is given as dBr. If what you are saying is true, the fact that this noise is through time generated at ever lower levels of DAC output might mean that I should check my amplifier for potential damage. Thanks

4 (edited by KaiS 2021-05-28 10:11:51)

Re: ADI-2 FS static noise/crackling noise

The simple test:
Play a digital fullscale level sinewave, like 400Hz or 1kHz, 0dBfs, from a Test CD or stream.
Dial up ADI-2’s Volume control until you hear distortions / crackling.

This is the limit for classic and jazz.

Because of possible intersample peaks the clean Volume dial limit is 3dB below this value, if you hear heavy compressed masters like modern pop, hiphop, metal and the like.


You amp doesn’t need to be brocken, the audibility of distortions is largely music dependent.
If you tell the model of the amp and which input used, I can have a look if I find out what it’s max. input level is.

Re: ADI-2 FS static noise/crackling noise

I did this, the level where distortion kicks in is -2.5.

The amp is Audio Analogue Maestro Settanta, the relevant specs might be:

- Line gain, measurement conditions: 20Hz-20kHz, value: 12dB
- Frequency response: attenuation -10dB, attenuation -20dB, attenuation -30dB
- Noise level, measurement conditions: Attenuation 0dB, Band limits 0Hz-48kHz, Value: 100dB sotto 1V

Thanks

Re: ADI-2 FS static noise/crackling noise

When the RME displays volume settings in dBr this means Auto Ref.Level is on and then it indicates the volume relative to maximum technically possible output.
At +4dBr you've been already overdriving the DAC itself, depending on the max level of the music.
Below 0dBr you're basically safe (the DAC chip has about 3dB headroom for intersample overs) from the DAC side.

But, as noted by KaiS, near 0dBr you are actually blasting a whole lot of voltage into you amp, notably if you use balanced interconnect cables, where 0dBr will output 7Vrms which may overload your amp's input before the internal volume control.

Normal consumer devices like CD-players put out 2Vrms for full scale signal, in comparison.
To get there with the RME, turn Auto Ref. Level off and set Ref.Level to +7dBu or +13dBu (see manual, section 31.13 Operation in the Hi-Fi Environment).

7 (edited by KaiS 2021-05-28 17:14:29)

Re: ADI-2 FS static noise/crackling noise

laudio wrote:

I did this, the level where distortion kicks in is -2.5.

I‘d suggest to use -5.5 or -6 dBr (watch out for the Auto Reference Level’s switching point, displayed in the blue line above the dBr volume).
Use the level where ADI-2 DAC just switches to the next lower Reference Level.

This way you make full use of the DAC chip’s dynamic range and still have the Auto Reference Level function handy.

Re: ADI-2 FS static noise/crackling noise

I tried both suggestions and they work fine with very similar audible results.  After operating the DAC for a few months in factory settings I managed a quite effective room correction with the EQ, which was spoiled by not knowing how to operate the output level and the Auto Ref level! Thank you both for the crash course and KaiS for your patience.

Re: ADI-2 FS static noise/crackling noise

Hello,

I’m new on this forum. Recently buy Adi-2 dac FS. Very good dac. I set Reference level to +7dBu (Auto Reference level ON). And volume -7dBr.
But I hear noise/crackling noise. No B/T. No EQ. No loudness.
My amp is Exposure 3010s2d integrated.

regards,
Simon

10 (edited by terrys999 2021-06-08 16:48:36)

Re: ADI-2 FS static noise/crackling noise

simongrega1 wrote:

Hello,

I’m new on this forum. Recently buy Adi-2 dac FS. Very good dac. I set Reference level to +7dBu (Auto Reference level ON). And volume -7dBr.
But I hear noise/crackling noise. No B/T. No EQ. No loudness.
My amp is Exposure 3010s2d integrated.

regards,
Simon

You should set +7. Auto off. Volume lock at 0.0
Find out what your amp voltage is ,  rca and xlr.

Example my amp is cxa80 4v xlr 2 v rca.
+13 is max I can use without loudness ect....

There’s a few posters who will answer your queries better.

Re: ADI-2 FS static noise/crackling noise

@terrys999: sorry, but I don't get the point why somebody should turn off autoreflevel.

Like KaiS wrote in post#7: with autoreflevel enabled, you see where the device switches to the next lower reference level.
At exactly this point you have the highest dynamic range / SNR of the DAC.

And on top of that, you still enjoy all the benefits of autoreflevel when, for example, EQ adjustments change the volume and the switchover from the previous or next reflevel must be done correspondingly earlier or later when you operate the volume knob.

Allow yourself the pleasure and make this little experiment: set the volume control of the DAC with activated autoreflevel to a value just before switching to the next higher reflevel and then turn the bass control and increase the bass by 0.5dB. And immediately the Reflevel changes to the next higher value, because the EQ adjustment has increased the volume of the output signal and the optimum reflevel is automatically calculated by the ADI-2 DAC/Pro. Easier is not possible.

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: ADI-2 FS static noise/crackling noise

ramses wrote:

@terrys999: sorry, but I don't get the point why somebody should turn off autoreflevel.

Like KaiS wrote in post#7: with autoreflevel enabled, you see where the device switches to the next lower reference level.
At exactly this point you have the highest dynamic range / SNR of the DAC.

And on top of that, you still enjoy all the benefits of autoreflevel when, for example, EQ adjustments change the volume and the switchover from the previous or next reflevel must be done correspondingly earlier or later when you operate the volume knob.

Allow yourself the pleasure and make this little experiment: set the volume control of the DAC with activated autoreflevel to a value just before switching to the next higher reflevel and then turn the bass control and increase the bass by 0.5dB. And immediately the Reflevel changes to the next higher value, because the EQ adjustment has increased the volume of the output signal and the optimum reflevel is automatically calculated by the ADI-2 DAC/Pro. Easier is not possible.

It depends on your needs, you can use a such perfect and sophisticated tool in so many different ways.

If one uses the RME ADI-2 DAC as a DAC only (and do not need any DSP function like EQ, Loudness, B/T etc.), a fixed reference level and a locked volume is safer (I used to do that on my previous integrated amp).
Today my RME is also my preamp and I use the RME volume control and DSP, so I turned AutoVolRef back on.

If autoref level was mandatory, RME wouldn't allow us to deactivate it wink

ADI-2 DAC (with stock PSU) - Neumann KH 310 A monitors - Cheap USB and XLR cables

13 (edited by ramses 2021-06-08 18:02:44)

Re: ADI-2 FS static noise/crackling noise

Right, but maybe you didn't get my point completely.
Terrys999 said "you should set +7. Auto off." 
Why should?
As you mentioned yourself, there are several ways. So you could do it this or that way ;-)

I would recommend keeping autoreflevel enabled to have more other options. Then you can quickly turn the volume knob to quickly check, whether your current setting is still the optimum for highest dynamic range / SNR.

The best recommendation is based on best practise and where you can tell real reasons why this could or would be an advantage to you. For me -15 dBr is e.g. easy to remember and I can validate it at any time as explained above.

You're mileage may vary, only my $0.02 to this topic ;-)

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub13

Re: ADI-2 FS static noise/crackling noise

simongrega1 wrote:

Hello,

I’m new on this forum. Recently buy Adi-2 dac FS. Very good dac. I set Reference level to +7dBu (Auto Reference level ON). And volume -7dBr.
But I hear noise/crackling noise. No B/T. No EQ. No loudness.
My amp is Exposure 3010s2d integrated.

regards,
Simon

Hello,

Now I have Reflev on the +7dBu (Auto Reference level ON) and volume on -11 dBr. No noise/crackling. And still enough room for B/T, EQ....
The sound is very good.

Regards,
Simon

Re: ADI-2 FS static noise/crackling noise

Glad you solved your problem laudio.  My integrated amp's max input voltage is 2v before it is overdriven.  I use my RME ADI-2 FS as DAC only.  I want the DAC to output 1v through XLR outputs, so I used this calculator to determine reference level and volume required to output 1v.

http://www.sengpielaudio.com/calculator-db-volt.htm

I need a Level Lu value of 2.5 to output 1v. So I set my DAC to the following:

7 dBu (DAC reference level)  +  6 dB (since XLR is used)  + -10.5 dB (Volume level of DAC) = 2.5

Magnepan 1.7i,  Luxman 509x,  RME ADI-2 DAC,  RPI4 Streamer

16 (edited by N00b 2021-06-15 12:41:15)

Re: ADI-2 FS static noise/crackling noise

If I may, if your integrated amp max input voltage is 2 V, you should set the XLR output of the DAC to 2 V.
2 V RMS is approximatively 8 dBu, so if you set the unit at +1 dBu RCA (so +7 dBu XLR) with volume at 0, you should be fine (1,73 V).
If you want to be 2V exact, it is +13dBu (+ 7 dBu RCA) and Volume to -4.5 dB.

You can see the manual on page 62, with more example.
https://www.rme-audio.de/downloads/adi2dacr_e.pdf

ADI-2 DAC (with stock PSU) - Neumann KH 310 A monitors - Cheap USB and XLR cables

Re: ADI-2 FS static noise/crackling noise

I didn't mean to hijack laudio's thread, but I guess it is related.

Thank you N00b,  I am not an expert in this, so I always welcome recommendations.  Why do you say I should target for 2v?  I emailed Luxman with the question and here was their response:

"Hello Mr. Berlin,

The Luxman L-509x is designed to produce full output power, at optimal S/N ratio with 180mV signals received via the balanced or (unbalanced) line inputs.

Two volts or more, is likely to overdrive these inputs, produce possible distortion and is otherwise an unnecessary signal level. Hope this helps.

Regards, JP"

The real question is, how close to 2v should I aim for?  How much headroom is needed?

Magnepan 1.7i,  Luxman 509x,  RME ADI-2 DAC,  RPI4 Streamer

18 (edited by N00b 2021-06-15 15:37:39)

Re: ADI-2 FS static noise/crackling noise

daleberlin wrote:

I didn't mean to hijack laudio's thread, but I guess it is related.

Thank you N00b,  I am not an expert in this, so I always welcome recommendations.  Why do you say I should target for 2v?  I emailed Luxman with the question and here was their response:

"Hello Mr. Berlin,

The Luxman L-509x is designed to produce full output power, at optimal S/N ratio with 180mV signals received via the balanced or (unbalanced) line inputs.

Two volts or more, is likely to overdrive these inputs, produce possible distortion and is otherwise an unnecessary signal level. Hope this helps.

Regards, JP"

The real question is, how close to 2v should I aim for?  How much headroom is needed?

180 mV (-12,67 dB) is a very low input sensitivity... I misread you (I thought the sensitivity of your amp was 2 V, my bad).
So you can:

  • Use the RME as a DAC only and set it to -1 dB level RCA (+5 dB XLR) at - 7dB volume level using XLR.

  • Use the RME as a DAC only and set it to -1 dB level RCA (+5 dB XLR) at -1 dB volume level using RCA (you optimise here the resolution of the DAC). XLR won't enhance "sound quality" unless you have >10 meters of cable... Better here to connect it with RCA.

  • Use the RME as a preamp (connecting it to the Main in of your amp). You turn auto vol ref ON on the RME and you handle the volume on the RME; you can use here the unit at its full potential (dynamic loudness is a must have... You can also use the EQ for your room correction etc.). The input sensitivity of the main IN of your amp is 1.1 V (3 dBu), but in that case scenario the RME automatically switch to the appropriate output level.

ADI-2 DAC (with stock PSU) - Neumann KH 310 A monitors - Cheap USB and XLR cables