Hi Tony!

Barring an actual NEED for the Analog inputs of a Pre, or Integrated amp, your plan to go direct from RME to your Amplifier is an excellent one!    Why add noise/distortion to the signal path with components that don't to be there?

I like your Plan.  Go for it!

Best!

Curt

PS:  Hi RP!! 

The simple answer is "yes", RME ADI-2 DAC or Pro FS makes a perfect fit to any power amp.

Skipping the pre-amplifier is removing a source of noise and distortion.
If you do not need the input source selection a preamp offers you get a cleaner path without.

For those reading along here:
The mentioned rule of 20, as ratio of load to source impedance, makes sense for only very special situations where the current drive capability of an output is very low, like with tube preamps.
Loading a tube preamp's output e.g. with to low impedance results in distortions and a bad low frequency response.

But still this so called rule of 20 is just a generalization and wants us to look more detailed into the situation.
BTW, technically we know this as the rule of 10, which simply characterizes voltage-matching (-interfacing), opposed to power-matching (-interfacing).

Anyway neither does apply here as the operational amplifier buffered output of the ADI-2s can drive almost any thinkable impedance, without negative side effects.

What matters is, if the interfacing voltages ADI to power amp fit together.
If this wasn't the case you get either noise or not enough drive on the power amp.

The ADI-2s are perfectly variable here with their different (even auto-) reference levels.

Specially the auto reference level is matching not only between different static setups.
Auto reference level also dynamically adapts to the users loudness demand to optimize signal to noise ratio without compromising maximum output level.

Hi all.

My ADI DAC is connected XLR to Plinius power amp and I'm more than happy with the sound quality
I have Auto Ref Level - ON - as I trust ADI to do best job.
Anyway, I was always curious what the numbers say and wondering if these values are really best for me.
I never had opportunity to ask you this question guys, but finally I dared. I'm not techie engineer so please forgive me if that's all obvious for you.

My ADI shows Ref Level in steps as follows:

*    up to -21.5dBr VOL      -5dBu (auto)
*  -21 to -15.5dBr VOL      +1dBu (auto)
*  -15 to -9.5dBr VOL        +7dBu (auto)
*  -9 to 0dBr VOL              +13dBu(auto)

I normally listen at -50dBr VOL (not to disturb neighbours)
At -40dBr VOL - it starts to be loud(but nice   )
At -30dBr VOL - it is VERY loud and I never go over -30 (not to blow my speakers haha!)

I never heard any distortion (I believe).
I'm only asking to satisfy my curiosity and maybe learn something.

Are all these values showed good for me? Nothing there to improve?

Regards, Siemak

Hi Siemak,

When we look at your figures, we see that your amp is very sensitive.
As KaiS said, you can buy pads to optimize your setting. I think that with -20 dB pads, you would optimize your SNR and always be in the best volume area of the ADI. And you wouldn't put your speakers at risks in case of a 0 dB accidental volume setting.

Please learn more in the link provided by KaiS

Thank you all for your considered responses.  We just moved the knowledge bar higher.
The one last possible benefit is the the ADI has >120db channel separation. This compared to even 65db on integrated amp.
I am hoping that I will attain better soundstage imaging by feeding that 120db separation signal directly into a dual mono design power amp such as Musical Fidelity A3CR.

Kudos all!

Indeed, Tony you can trust that your RME would hardly be a limiting factor in terms of Separation.  As Kai illustrates, there is a "threshold of audibility" factor which deserves consideration.    Where Speaker position, etc is concerned, I too have been noted to be quite insistent on this!  How easy it is to spoil a wonderful Speaker with Poor Placement.  Be Picky!! 

On Topic, there is more than just "Technicals" involved with the Pads, Gain Staging, etc.  There's a "Safety Factor" !!!

When you routinely listen at -50... and then start flipping thru Set-Ups, and land upon one which references a FAR HIGHER Volume Setting...HANG ON!  You are you about to experience an Audio-Cardiological event of Epic Proportion!!    Your Speakers might break too.  Don't do that.  This can be remedied within Set-Ups, but one thing at a time.

Best to All

Curt

Hello, I am going to do do just that this friday, thing is, I am afraid, how have you set your volume directly to the power amp?

rca out connected to my pre-amplifier right now is a -3db, because when I plug the cd player and such I see that's the same lvl output the other devices send, but power amp has no volume so which will be the safe volume to set in xlr-out when I plug the amp in order to not blow my years, my head and the speakers in the process?

I am more or less in the case of the op.

I have an integrated amplifier to which I connect via rca output, and I will use xlr out to connect to the new power amp. Still not sure If I can plug both and such.

Thanks so much will do just that.

additional question.
So having my DAC to -3db is wrong when connected to the integratet amp? I matched that volume to the coaxial out volume of my cdplayer, so I thought that would be the ideal setting.

Amazing!! You seem to know a great deal of this and I am pretty much lost in this world

My RME is has autoref lvl on, which says +13dBu, I set it to volume 0dBr and it sounds great still, so it seems I am good for now, not sure if to keep increasing it and see or I may break something.

My integrated amp is a moon 220i, with specs (if we believe them):

Configuration ......................................................... Stereo
Class Of Operation - Amplifier .................................. Class A/B
Single-ended inputs ................................................. 5 (RCA)
Mini-jack input ........................................................ 1 (1/8”)
Input Sensitivity ..................................................... 370mV – 3.0V RMS
Input Impedance ................................................... 11,000Ω
Preamplifier output ................................................. 1 (RCA)
Headphone output ................................................... 1 ( 1/4” Strereo TRS)
Output Power @ 8Ω ................................................ 40 Watts per channel
Output Power @ 4Ω ................................................ 80 Watts per channel
Output Impedance .................................................. 0.04Ω
Damping Factor ...................................................... > 200
Signal-to-noise Ratio .............................................. 101dB @ full power
Maximum Output Voltage ........................................ 20 Volts
Slew Rate ............................................................... 20V/μs
Maximum Current Output ......................................... 14 amperes
Frequency Response .............................................. 10Hz - 100kHz +0/-3dB
Crosstalk @ 1kHz ................................................... -78dB
Intermodulation Distortion ...................................... < 0.07%
THD (20Hz - 20kHz @ 1 watt) ................................ < 0.015%
THD (20Hz - 20kHz @ 40 watts) ............................ < 0.03%

I wish I knew how to use that calc or know which values to set in which area but I am totally cluless

What I think I got is the the third column of the calc?

I set "voltage V" to 3.0 based on "Input Sensitivity ..................................................... 370mV – 3.0V RMS"
which gives
Level Lu 11.760912593 dBu
Level Lv 9.542425094 dBV

Still not sure what volume to set in the RME, since it says dBr

When I get the Behringer A800 and plug the XLR cables to it this may be a nightmare too...anyways in this case I'll do as you said to be safe!

Thanks a lot for the tips, greatly appreciated !!

Indeed , I paid a lot attention to that you said, I worried about blowing my ears and the speakers in the process if not, because that little beast gives too much power but will let me play around with setups and see what class d is about.

Cheers!

Hey Curt962, thanks for your kind and friendly offering, so here it goes...

My behringer a800 is here, quite affordable and not poisoning too much the impecable sound that comes from the RME from what I am able to perceive, so I am enjoying it tons now! and they seem to drive my speakers greatly so, double happy.

now the information you ask...

As I think I mentioned earlier, I use XLR out of RME to connect to this AMP.

As N00b suggested me, I have set auto ref level on with it, unlock the volume and I am usually using it at -35dBr for extended listening and to -25dBr volume generally not so long but very confortable, generally at these levels the current power indicator do not even getting lit.

Past -25dbR it starts to get too loud for extended listening, but I generally push to even -10dBr and such for the good songs, at -1dBR it is definetly too loud for me , leds of the power indicator get to very high.

Also note my listening room is small (11m2), so It doesn't take too much volume to "fill it up".

As for the more relebant specs of the amp as advertised:

Output circuit type Class-D
Distortion (4 Ω @ 150 W @ 1 kHz) <0.08 %
Damping factor >160 @ 8 Ω
Frequency response @ -10 dB below rated output power 20 Hz to 20 kHz, +0/-1 dB
Frequency response @ -3 dB 10 Hz to 30 kHz
Signal-to-noise >100 dB (A weighted, 20 Hz to 20 kHz)
Voltage gain @ level control max Balanced: 30 dB / RCA: 41 dB
Input sensitivity @ level control max XLR: +4 dBu / RCA: -10 dBV
Input impedance
XLR / ¼ " TRS 20 kΩ, balanced / 10 kΩ, unbalanced

Also note I set both Behringer A800 gain volume notches to 50%.

Cheers and thank you!

Hello again

I hear no noise, or if any barely to be noticeable or that could even get to ever bother, I would need pretty sensitive ears. My loudspeakers, buchardt s400 are not very sensitive either, so no hiss or anything.

Care to explain the reasons of what you are saying? Which is the ideal volume levels of the DAC I should be setting?

I could perfectly turn down the gain level control in the amp , in fact I am not sure how to set them for maximun results with the DAC so that's why I went 50%

I think my kids won't come and play witht he DAC or amp so... no issues with that

Edit: Also take into consideration I am totally clueless regarding technical stuff, so I dont know what are -20dB pads or "EZ thing"

mm I answered but dont know for sure where the answer went... don't see it in the thread.

Anyways, will try tomorrow, set amp gain as low as possible and try to get RME to get loud at those points.

Thanks for the tips!

Pads are attenuator that you plug between the DAC and your amp (those babies for example).
Please see that topic:
https://forum.rme-audio.de/viewtopic.php?id=25399

EZ: means "easy" Young blokes like Curt in the US write it that way 

Thanks @N00b
I understand what pads are now in this case.

@Curt962

as you mentioned I set the gain of the amp for left and right to about 10% and now I RME is at about -10dBr when I listen to music loud but confortable, getting the most of the dynamic range I can get.. right?

As for the rest you mention, I am delighted with you guys, this is a most helpful community and I hope I can give some of that back, specially on tips like those you have given me to get the most of the dynamic range of this special little device we all know, the RME ADI-2 DAC.

I bought it as an endgame for me because I was not willing to spend more perhaps in a very long time in any other device... and now the more I use it.. the more I enjoy having it, and not only that, even the most demanding objectivists find it amazing, so in general it is an absolute pleasure of a device.

Thanks thanks!

ahhh, you tease...

please tell us how you configured that and your experience with it, last night after reading your comment I grabbed the manual and read about the loudness section.

A few questions come to mind... Trebel/Bass Quality factor? How to set bass freq?

Also, I generally tend to prefer neutral sound but since I am generally very close to the speakers (nearfield they call it?) I usually suffer lack of bass due to that proximity, so I have been tempted to play with loudness sometimes... perhaps it is the right time now?

Loudness is for listening at significantly lower level then usual.
It's meant to keep the perceived bass/midrange/treble balance as independent from listening level as possible.

The procedure below works the other way round than described in the DAC’s manual page 14.
I assume that at "normal" and slighly below listening level an unchanged, "No Loudness" sound is prefered.

• Basic Setup:
Determin your "normal" listening level's dB value.
This may vary slightly depending on the source and music.
Estimate an average "normal" dB value.
• Do all settings needed for this to sound best, EQ, Bass, Treble ...
• Set the Loudness "Low Vol Ref" 25 dB below this "normal" listening dB value.
This way Loudness correction kicks in 5dB below normal listening level, leaving all above untouched.

• Fine-Tuning:
Now dial down to your usual "low" listening level.
•  Adjust Bass and Treble Gain to an amount that the bass/midrange/treble balance sounds comparable to what you hear at your "normal" level.
Go back and forth beween levels to check.
• Now listen at different levels again and fine-tune the Low Vol Ref.
The higher "Low Vol Ref" is set, the stronger the Loudness effect.
Don't go above 20dB below your "normal" dB value, or Loudness will effect your normal listening instead of doing it's primary job, keeping the sound balanced at lower levels.

To give you figures:
My "normal" listening level: -18dBr (Auto Ref Level on)
Loudness Bass Gain: 9.5dB
Loudness Treble Gain: 7.5dB
Loudness Low Vol Ref: -42dB (Loudness kicks in at -22dBr)

With different sensitive headphones, speaker setups, different loud sources or music, "normal" listening dB value has to be re-determined and "Low Vol Ref" adjusted accordingly.

Finally to mention:
1. Q-factor and frequency is not user-adjustable in the Loudness setup.
Loudness works with it's own factory preset values, DAC manual page 59.
Q and f is in the separate Bass/Treble control only.

2. Loudness is NOT the right tool to correct transducer flaws.

Ezra,

To provide a Scientic Basis to describe the actual function of the Dynamic Loudness feature, refer to this overview of the Fletcher-Munson Studies of the 1930s.  This research concluded that as listening levels decrease, Human Hearing Acuity diminishes in a predictable manner. 

https://ehomerecordingstudio.com/fletcher-munson-curve/

To this end, Dynamic Loudness is a VERY USEFUL tool to preserve our perception of balanced, full-range sound over a wide range of Volume Settings.   Dynamic Loudness is NOT a fixed EQ, but rather one that varies depending on your chosen Volume setting.    The RME/AKM implementation of same must surely be the FIRST time it has been done correctly in an Audio Product.  I love it!!

Refer to your manual for guidance on its use. 

Enjoy!!

Curt

Invaluable advice/guide btw, thank you so much!!! Tinkered it a bit now but will do more when I'm off work hours

It is, one way, if you don't care about the result - as generations of music listeners did - take it as a switch that boost bass and treble, making overall sound louder, fuller.

It still is if you follow my cookbook.
To get the full benefit just a little bit of tuning is needed.

It's like fastfood vs a selfcooked meal.

I don't know if this is what you mean, but some devices in the current range of Yamaha amplifier have a variable loudness setting, like this AS-301 knob:

And it normally is. 

@ezra:  Just set your Low Vol Ref (IO Menu) at 20db BELOW your normal Listening level.   Feel free to experiment with a few db higher/lower.  20db is simply the suggested value given in the User Manual.   Now when you DIM the volume to answer the phone, or sit down to a semi-peaceful dinner...things will still sound full bodied.   No intellectual gymnastics required.

Have Fun,  and Enjoy!

Curt