[IXOYE]

Thanks for posting these questions. I thought I had mine set right, but now I'm not sure. I see OVR sometimes, but I never paid much attention to it. Seems I need too.

I'm using the XLR out with it set to +7db and volume locked at 0 db.... That might not be right...

Probably not, I wonder if even -6 db are enough with heavy applied EQ.

 

[Jagamov]

What i use

Looks like we read the manual...LOL

 

[Simon Patten]

I'm thinking of hooking up my RME ADI-2 FS with an external amplifier, I found this info on the RME forum.

"CASE 1, analog volume control:

To maximize ADI-2's dynamic range (S/N ratio) it's best to have ADI-2's volume control at 0 dB, using the external ANALOG AMP's volume control to set listening level:

• Set external amp's volume control to middle position or some above.
• Switch OFF ADI-2's "Auto Reference Level".
• Set ADI-2's volume control to 0 dB.
• Select the reference level that fits best to your loudness demands.
• Use the ext. amp's volume dial to control the final loudness.

• Once you start to use any of ADI-2's DSP functions like e.g. the EQ:
- Compensate possible level boosts with ADI-2's volume control until the Level Meter does not show overs.
- Or switch back On "Auto Reference Level" and let ADI-2 calculate the best value.

CASE 2, digital volume control:

If you want to use ADI-2's digital volume control to set listening level, ADI-2 DAC / (Pro) has a clever option that increases the usable dynamic range by 18 / (20) dB: "Auto Reference Level":

• Switch ON ADI-2's "Auto Reference Level".
• Set ADI-2 DAC's (Pro's) volume control to -18 / (-20) dBr. (1)
• Set ext. amp's volume control (or passive attenuators) slightly above your normal listening level.
• Use the ADI-2's volume control to set the final listening level.

Now ADI-2 automatically adapts the reference level for best fit to your loudness demands, while maximizing it's DAC's dynamic range.

If your external amp does not have a volume control, use variable passive attenuators to fit the level:"

If I want to use all functions such as, for example, Loudness on RME I have read that only CASE 2 will work, but what I wonder about is why I should only raise the volume on the amplifier to a little above my normal listening level, why not set it at max? Am I not using the amp to the max if I doesn't?

Interesting post, thanks. Was it written by a user or RME themselves?

I am a newbie compared to some of you but my theory is that two volume controls in the chain is not a good thing so I set my amp's volume control to max (zero resistance) and control it from the ADI-2. This is particularly beneficial with the S17 Pro and it's dodgy volume control (on early models like mine) and being class A it's running flat out anyway. It's certainly an interesting topic for discussion though and I will consider your/their suggestions.

 

[evhvis]

Probably not, I wonder if even -6 db are enough with heavy applied EQ.

You can easily see that when you apply EQ. The first horizontal line is 5dB and second is 10dB so if you go far above the first then you just turn the volume down a bit when using that EQ. It is rare that you need more than 6db of EQ on a headphone though. No point in setting the volume to fixed IMO.

 

[IXOYE]

You can easily see that when you apply EQ. The first horizontal line is 5dB and second is 10dB so if you go far above the first then you just turn the volume down a bit when using that EQ. It is rare that you need more than 6db of EQ on a headphone though. No point in setting the volume to fixed IMO.

So it's the same as adjusting down the preamp gain in APO EQ then, but shouldn't Auto Ref take care of that?

 

[evhvis]

So it's the same as adjusting down the preamp gain in APO EQ then, but shouldn't Auto Ref take care of that?

When you have autoref on the -6 is maximum headroom until 0dB with outputstages at max and the DAC will switch the outputstages upwards until it runs out. The available ones are -5dBu, +1dBu, +7dBu and +13dBu. You will have +1dBu at -12 on the volume. If you are at -6 then auto ref will select +7dBu, but it also only has 1 more stage which is 6dB higher. If you add 9dB of EQ then you might have some signals going above 0. Depending on the music recording volume you may or may not get digital clipping with 9dB of EQ. If you listen to loudness war victims then you are likely to get clipping while well recorded music with a good amount of headroom will be fine.

Filters interpolate which can cause the filtered signal to go above 0dBFS. Now 0dBFS is "maximum" volume of the signal and going above the maximum volume of the DAC chip will cause digital clipping which is nasty. Maximum volume of the DAC and "maximum" volume of the signal at a bit depth aren't nessicarily the same as the DAC maker or chip maker can add headroom to handle intersample overs. Basic example of intersample overs is that you can have data points that indicate a sinewave, but the datapoints might not be at the peak of the sinewave causing the filters to add signals that go over the theoretical volume of the given bit depth, which works fine for the processing as it often is done at a higher bit depth but can cause digital clipping in the conversion. Most if not all ESS chips have issues with intersample overs unless the implementer has taken steps to prevent this. Afaik the ESS chip versions are built by RME with +2.5dB headroom for intersample overs and I do believe the AKM chips have around 3dB of headroom to handle intersample overs.

The way autoref works is that it switches the output stages to increase volume, but the volume is always shown as distance to +13dBu stage. You can easily test this for yourself by turning on autoref and watch the display go from -5 to +1 at the switch from -18 to -17.5 and it will switch at -12 -> -11.5 and also at -6 -> -5.5. When you turn on EQ then it will try to adjust the autoref to suit the EQ but at -6 it only has 1 stage of +6dB available so it can't compensate for more than that. Therefore you should turn down the volume to the max amount of EQ you do if you go above 6dB (easy to see in the EQ graph). It should be rare that you need more than 6dB of EQ so it is generally safe to have it at -6 and auto ref.

 

[Jagamov]

After messing with it and finding my highest level songs, I settled on +7 ref level and -6.0 on the volume. +13 ref level worked fine too, but my amp volume was very loud at 11 o clock on the dial. I didn’t want to put my amp in negative gain, so the +7 works great.

No more OVR now. It really becomes clear once you start messing with it and you understand the relations each setting has.

 

[IXOYE]

Therefore you should turn down the volume to the max amount of EQ you do if you go above 6dB (easy to see in the EQ graph). It should be rare that you need more than 6dB of EQ so it is generally safe to have it at -6 and auto ref.

Thanks, I use max +5.5db Base-Shelf on one of my headphones EQ profiles so -6db should be perfectly ok then

 

[hikaru12]

Hi guys I recently acquired this DAC. Has anyone paired it with something like an Uptone JS2 (which provides 7A at 12V) to any noticeable effect? I usually pair my DDC (my Pi2AES with a good quality LPS as the backbone of my system so I can definitely see that there could be improvement in this area for this DAC.)

 

[Simon Patten]

Similar to the post above; have any of you tried upgrading the power supply on our ADI-2s? I know that RME say it doesn't make any difference but surely a high quality linear PSU like the one below would improve the sound, or is their internal power handling really that good?

https://www.ebay.co.uk/itm/272180528524

 

[hanumanbob]

Have any of you tried upgrading the power supply on our ADI-2s? I know that RME say it doesn't make any difference but surely a high quality linear PSU like the one below would improve the sound, or is their internal power handling really that good?

https://www.ebay.co.uk/itm/272180528524

It's German tech so I think it is just fine.

 

[hanumanbob]

You can easily see that when you apply EQ. The first horizontal line is 5dB and second is 10dB so if you go far above the first then you just turn the volume down a bit when using that EQ. It is rare that you need more than 6db of EQ on a headphone though. No point in setting the volume to fixed IMO.

If you have to apply major EQ then something is wrong somewhere .

 

[evhvis]

If you have to apply major EQ then something is wrong somewhere .

With a lot of open backs it is the low bass that mostly needs EQ. I do agree that if you need major EQ for your headphones then you bought the wrong headphone.

 

[jmimac351]

Similar to the post above; have any of you tried upgrading the power supply on our ADI-2s? I know that RME say it doesn't make any difference but surely a high quality linear PSU like the one below would improve the sound, or is their internal power handling really that good?

https://www.ebay.co.uk/itm/272180528524

Matthias at RME says the NT-RME-11 is the 40 watt power supply included with the ADI-2/4 Pro SE. It has an IEC connector / 3 prong mains plug. I have both the ADI-2 DAC FS and the ADI-2/4 Pro SE. The power supplies are indeed different.

With the DAC FS, I did have some hum related to the RCA when the RME unit was OFF, connected to the amp via XLR, and the amp ON (to keep amp warm). I haven't tried the NT-RME-11 power supply to see whether it resolved that scenario. I was able to immediately make the hum go away plugging shorting plugs in, but didn't like that either.

If I had an ADI-2 DAC FS and wanted a better, regular power supply, I would just buy the NT-RME-11. I guess I should play with the ADI-2 DAC FS with the NT-RME-11 power supply to see whether it makes that RCA hum issue go away. Even with that 1-off issue... it didn't make me like the DAC FS any less. In fact, I liked it so much that I bought the ADI-2/4. I wanted analog in and every bell and whistle. I love it.

https://www.rme-usa.com/power-supplies.html

If I wanted to do something special with power supply, I might not even buy the NT-RME-11. Matthias has posted ideas for how to run the unit off of a battery pack - and I may or may not play with that. I listen so much that I'd have to figure out run time / charging, etc. I'd rather spend money on something very different like a battery power supply than a bigger, linear power supply, transformer, etc.

 

[hikaru12]

Yea like everyone else here I’m curious how it does on an upscale LPS like the Uptone JS-2.