Topic: Volume control feature of RME ADI-2/4 PRO SE

Hi forum fellow members. I just want to share information, that I couldn't find in manual, but I think it could be useful for those who want to get maximum from their RME ADI-2/4 PRO SE while they listening to the music, maybe the same you could get from other RME products.

So I have bought my RME ADI-2/4 PRO SE approx. 3-4 month ago. The main reason why I wanted to buy it, because it has 2 separate line outputs one of which I connected to stand alone headphone amplifier and the other one to my main audio monitors.

I spend some time to understand which settings I need to use, but from the beginning all was fine (I mean I didn't change settings much).

I heard from one blogger on YouTube that if you want to get the most of your RME, setup your volume control to 0 Db and control it from your preamplifier or amplifier. When I did it with headphones amplifier the sound become natural, powerful, I have no complaints, it is what it should be.

But I can't do the same with my audio monitors, because 0 DB is just too loud. So I started to change the volume while listening. And I heard 4 clicks when change loudness:

at 0 Db;
at -11 Db;
at -17 Db;
at -23 Db.

If I setup volume at -0.5 or -3 or -9 Db the sound have changed it's character. But If I setup one of this four loudnesses I heard the most pleasant sound from my setup. So I setup -23Db to my audio monitors and OMG, the sound improves drastically.

So, it might help you to love your devices even more and hear music as it should be, with pleasure.

Good day to everyone.

Re: Volume control feature of RME ADI-2/4 PRO SE

Instead of listening to some bloggers on YouTube, you'd better spent that time reading the manual about the RME's volume control implementation, including 5 different reference levels and the auto ref function, and why it is much superior to controlling volume elsewhere. And if you combine this with the dynamic loudness function, you can accommodate for the perceived frequency response differences.

And what's wrong with the RME so that you had to use another headphone amplifier?

Fireface UCX II + ARC USB > ADI-2 Pro FS R BE > Neumann KH 750 DSP + MA 1 > KH 120 A

Re: Volume control feature of RME ADI-2/4 PRO SE

Hello unpluggged, I think you need to bee more friendly, please do not bite me, I thought this forum is to discuss devices but not arguing with each other.

If I can understand all that manual contain as usual user I think it would be more productive for me, but unfortunately I do not understand some parts of the manual. That's why I shared information in the form that it might be perceived people who are as I'm non-technicians in the first place.

About amplifier, why do I need it for my headphones.

First of all, I believe and I can hear the difference, that each device must provide only one function. For example DAC, preamp, amp, etc.

The second is that you could implement some functions, in RME specifically, which has really good sound, but some which is not. In my opinion the DAC function of RME is a really good sounding element. But if you compare headphone amplifier section of RME to separate headphone amplifiers, you probably discover that separate headphone amplifier sound much better.

The third thing that I want to add tubes to hear warmness of the sound.

In my setup RME balanced headphone output sounds worse than balanced output from McIntosh MHA200 (with Genalec tubes) with Audeze LCD-5. RME headphones output at any volume has distortion which is noticeable (I can hear it) and the sound itself if you compare it with MHA200 has less life in it.

I hope that I answered your question.

Be well.

4 (edited by ramses 2024-07-14 14:57:03)

Re: Volume control feature of RME ADI-2/4 PRO SE

I interpret unplugged's post as a well-intentioned recommendation and can only emphasize it.

It is clear that the YouTuber is not wrong; at 0dB volume, the device has the highest SNR and the highest dynamics. However, it would blow your ears off if the connected device is a powerful power amp or active monitor. Here, it is necessary to differentiate whether the device is connected to a preamp or a power amplifier.

If one had read the manual, they would already know quite a bit about the special features of the ADI-2/4 Pro SE.

1. There are 5 different reference levels, and switching between them is done via relays, hence the clicking sound.

2. The Auto-reflevel feature ensures that, depending on the set volume, the optimal reference level is set to maintain both SNR and dynamics at a high level over a longer control range (with the ADI-2 Pro R BE which has 4 ref levels ~28dB). This also considers the settings for Bass/Treble, PEQ, and dynamic loudness.

While we are at it ... I created an Excel sheet where you can see the SNR depending on the volume and with auto reflevel activated for ADI-2 pro FS R BE (also for ADI-2 DAC FS), your ADI-2/4 Pro SE has one reflevel more, thus the volume range is higher, where SNR/Dynamic can be optimized). Here the screenshot:
https://www.tonstudio-forum.de/attachme … -v002-jpg/

3. Dynamic loudness is an additional, highly useful feature that prevents the sound from becoming too thin when the volume is turned down. Over a control range of 20 dB, bass and treble are dynamically boosted so that the perceived sound volume is not lost even at lower volumes. The dynamic loudness function is configurable; you can set the volume level at which the maximum boost should occur, and the maximum boost of bass and treble can be adjusted separately up to +10 dB in 0.5 dB steps.

If the output volume of the connected amplifiers or monitors is much too high in the range of 0 to -20 dB, this volume mismatch should be resolved. This forum thread describes how to achieve this in a sound-neutral way with switchable attenuators (usually from -10 to -30 dB): https://forum.rme-audio.de/viewtopic.php?id=25399

It is best to ask here in the forum directly, as what you find on YouTube is not always as great.

If you need any more assistance, feel free to ask!

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

Re: Volume control feature of RME ADI-2/4 PRO SE

The sound quality of the ADI does not change with different level reference settings. This is simply not objective "information" of any kind. We don't know what exactly is happening or what you are hearing.

Regards
Daniel Fuchs
RME

6 (edited by KaiS 2024-07-14 16:08:54)

Re: Volume control feature of RME ADI-2/4 PRO SE

Buddser wrote:

And I heard 4 clicks when change loudness:

at 0 Db;
at -11 Db;
at -17 Db;
at -23 Db.

If I setup volume at -0.5 or -3 or -9 Db the sound have changed it's character. But If I setup one of this four loudnesses I heard the most pleasant sound from my setup. So I setup -23Db to my audio monitors and OMG, the sound improves drastically.

As you noticed, the level steps at –11, –17 and –23 dBr are where mechanical relays change the analog reference level.

I once fell into the same trap, thinking to hear a significant sound change switching back and forth at that very steps.
Then I noticed, what I hear are the faint momentary clicks in the audio caused by the mechanical switching.

Only for that little switching moment the sound gets brighter when the relays change their contact positions.

After that moment, I can not distinguish any sound change except for the different level.


The proof:
There is another level step at -5 dBr that does not use relays, which does the same for the DAC as the others.
You did not notice it to “sound different” as there are no mechanical contact sound effects in the audio.



Finally, all that counts is you’re happy with your ADI-2/4 Pro SE.
Over the time you might discover even more of it’s qualities and features.
E.g. I never heard a more transparent, uncolored and clean (read “black background”) RIAA / vinyl preamp.

7 (edited by little-endian 2024-07-20 23:37:28)

Re: Volume control feature of RME ADI-2/4 PRO SE

What would be interesting to know is why RME implemented the relais based reference level switching in the first place.

At first sight, it sounds (no pun intended) reasonable as it preserves the SNR but that concept is given up anyway due to the math-based volume control before the DAC - for good reasons.

Now while DACs with analog potentiometers (which aren't common anymore these days due to practical drawbacks such as audible wear; the first Benchmark DAC1's were such a case) indeed preserve the SNR and dynamic range in conjunction to some extent (because they also lower the noise floor when reducing the volume), that theoretical advantage is none in real life as the whole listening situation and one's own ears limit the SNR anyway.

In other words: if not playing at maximum loudness close to the pain threshold, one loses SNR/dynamic range anyway as the upper part partly defines it and based on a constant noise floor, the SNR has to go down as the volume/sound pressure goes down.

The only practical advantage I could imagine might me that in the case of not having those relais switched stages, louder noise sourced might interfere on the way to the power amp and becoming more audible. Clearly, in theory, it is favorable to keep the line level as high as possible for transmission but I still wonder what real relevance that has given today's SNRs of devices.



Buddser wrote:

But if you compare headphone amplifier section of RME to separate headphone amplifiers, you probably discover that separate headphone amplifier sound much better.

Don't think so. Since RME's approach audibly and technically most probably already as good as it gets, if I were to really observe any differences, I'd rather suspect the other device intentionally changing the sound or doubt myself (also good from time to time).

Given the pristine technical implementation by RME, there is no sensible explanation why it should sound worse in any way.

Remember: if you can measure a difference, you might (!), often a big might, be able to hear it, but vice versa: if you can't even measure it, it simply isn't there. The claim and mantra that we can hear things which can't be picked up by technical instruments, is audiophile bullshit at its best and should be eradicated. Unfortunately quite the opposite is true: human ears are actually relatively lousy air pressure to electrical/chemical information transmitters and not getting better with age.

Buddser wrote:

The third thing that I want to add tubes to hear warmness of the sound.

Although you could also have that nowadays by the use of DSPs/equalizers, a legit approach if you want essentially what should be called "non high fidelity".

8 (edited by KaiS 2024-07-21 04:59:44)

Re: Volume control feature of RME ADI-2/4 PRO SE

There are a multitude of approaches for volume control.

Conventional continuous volume potentiometers are by far the worst:
They cause measurable distortions way stronger than those of a current DAC chip.

The choice of the relays based automatic reference level switching combined with digital volume control, called “Auto Reference Level” is a great move IMO.

The relay based analog reference level switching is there anyway and indispensable for a pro-audio device.
So why not use it for this clever function, keeping SNR and resolution high over the typical range needed for volume control?!


Don’t underestimate the human hearing:
Nature had millions of years to highly optimize the auditory system which not only consists of a releatively simple, albeit extremely effective mechanical system (*1) PLUS, and that’s the point, the most advanced data recovery system thinkable, called “brain”.

This does not automatically mean the audiofool bulls*** you can read in 95 % of todays forum posting is true.


(*1) The human mechanical auditory system already beats EVERY studio microphone exist in dynamic range.
Specifically the lower dynamic limit is at the edge of physically possible, a healthy young ear can almost hear the air molecules thermal movement!