Measurements of RME ADI-2 DAC and Headphone Amp

[JimmyBuckets]

Possibly you just copied marketing just changed from the AK4493 version. As I wrote to @JimmyBuckets in post above the specs seems the same between v2 and v3.

Yeah not sure what I was looking at

 

[soundwave76]

Question about the analog line out volume level -> is there a 'reference neutral level' to use for example when feeding a Stax amp? In other words, what would be the suggested volume level not to over-amplify before the Stax amp and vice versa apply too little volume?

 

[JimmyBuckets]

I adjusted my output level to give me maximum output range for the levels l like to listen at. Giving me the finest amount of adjustment around the volume I usually listen.

 

[soundwave76]

I adjusted my output level to give me maximum output range for the levels l like to listen at. Giving me the finest amount of adjustment around the volume I usually listen.

How did you do this specifically?

 

[JimmyBuckets]

How did you do this specifically?

I adjusted the volume on my main system to around 10 o'clock. With music playing, I starting with the volume at zero on the rme. Then just turned it up to slightly higher then what I normally comfortably listen at. Then I locked the output on the rme. In my situation it was more important to have a lot of range and fine adjustment when turning it down, more so then max volume level. I tweaked it a little more but that was basically my method. Hope that helps.

 

[soundwave76]

Thanks. I still wonder if there is a ’textbook answer’ to this question. I need to read the manual what is ADI’s line out volume level when set purely to a DAC mode bypassing the volume control.

 

[chips666]

Thanks. I still wonder if there is a ’textbook answer’ to this question. I need to read the manual what is ADI’s line out volume level when set purely to a DAC mode bypassing the volume control.

This may help, thanks to "Kais" from RME forum
Enjoy...

Two different approaches to use ADI-2 with external amps, how to set them up:

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.

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 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:
https://forum.rme-audio.de/viewtopic.ph … 42#p120442

SIDEMARK:
(1)
The volume figures change from dB to dBr when Auto Reference Level is “ON”.
The dBr relates to maximum achievable level with highest Reference Level then.

With “Auto Reference Level “OFF” the dB-figures (without r) relate to the manually choosen reference level.

 

[soundwave76]

Thank you!

 

[Comrade Sandwich]

@chips666 Really appreciate you taking the time to post that here. I remembered seeing that thread in the RME forums a while back but I was having trouble finding it.
Cheers!

 

[KSTR]

Sidenote to the above for the ADI-2 Pro:
Auto Ref. Level best works for the balanced outs. For unbalanced 1/4" outputs the last step from +19dBu to +24dBu isn't there physically so when you're past -5dBr in the volume setting then the DAC offsets back by 5dB but the make-up gain is missing, producing a drop step in relative level like this:

    |
o [ |     /| /
u d |    / |/
t B |   /
p u |  /
u ] | /
t   |/
    +--------->
     vol [dBr]

 

[skhan007]

Thank you so much @chips666 for the above guidance. I was trying to find this info and glad you provide such clear steps.

Apologies if this has been asked (still reading through 59 pages here): How does everyone feel about the amp section of the ADI-2 DAC? In hi-power mode, it seems to drive my ZMF Verite Open & Auteur headphones just fine. I think measurement data support the proper handling of the 300 Ohm headphones. That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

 

[TunaBug]

That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

The world is big place and I don't doubt that Some People(tm) use it with an external amp, but I'm skeptical of "virtually no one".

I can speak only for myself: most of my headphone listening is on my ADI-2 DAC with DCA Aeon Noire. I bought this unit specifically as a headphone amp, and it was chosen over the competition because of the DSP functionality and because the manufacturer is clearly dedicated to it. The RCA/XLR outputs on the back of my unit have never been connected.

 

[04gto]

Thank you so much @chips666 for the above guidance. I was trying to find this info and glad you provide such clear steps.

Apologies if this has been asked (still reading through 59 pages here): How does everyone feel about the amp section of the ADI-2 DAC? In hi-power mode, it seems to drive my ZMF Verite Open & Auteur headphones just fine. I think measurement data support the proper handling of the 300 Ohm headphones. That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

I have had three different versions of the RME ADI-2 DAC and the V2 version is little more powerful (see measurements here on ASR for confirmation) than the previous versions, but the amplifier is great as long as you don't have something like a Susvara or Abyss 1266 TC etc. As they need more power. My Hifiman Arya V2 are not very efficient and the RME has room to spare with those. Even with heavy EQ. I have compared the RME amplifier side by side with several other amps I have owned including: THX 887, THX 789, THX788 DAC/AMP, SP200 and JDS Labs Element 2 DAC/AMP. All of these, except the JDS Labs have much more power, but from a sound quality aspect the RME is as good or better than any of them. In fact for my preferences, I prefer the RME sound over all of them, except maybe the JDS & SP200. The 788, 789 & 887 sound a little 'thin' in comparison. Not bad just the notes in the RME have a little more heft to them. The SP200 has perhaps a little better bass than the RME and the JDS sound identical to the RME, I cannot tell them apart when using the RME as a DAC. However the DAC in the RME is better than the JDS. In summary: Unless you want the sound 'colored' (less clean) or thinner (maybe more 'airy' with less bass emphasis), or you need more power, the RME amplifier is very good.

 

[LTig]

Apologies if this has been asked (still reading through 59 pages here): How does everyone feel about the amp section of the ADI-2 DAC? In hi-power mode, it seems to drive my ZMF Verite Open & Auteur headphones just fine. I think measurement data support the proper handling of the 300 Ohm headphones. That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

I own the ADI-2 PRO fs and use its headphone amp daily with different headphones (DT990pro, K371, HD800). Using a separate amp makes no sense qualitywise. AFAIR @MC_RME once wrote in a posting why that's the case.

 

[Tks]

Thank you so much @chips666 for the above guidance. I was trying to find this info and glad you provide such clear steps.

Apologies if this has been asked (still reading through 59 pages here): How does everyone feel about the amp section of the ADI-2 DAC? In hi-power mode, it seems to drive my ZMF Verite Open & Auteur headphones just fine. I think measurement data support the proper handling of the 300 Ohm headphones. That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

THX789 is sitting rarely ever getting use after a groundloop solved itself one day. If sound quality is what youre looking for, the amp in the RME is good enough for basically every headphone out there. I personally use HD6XX on it, and a bunch of IEMs. I dont come close to using its maximum output.

I also use it to send signal to powered speakers and it’s great.

 

[KSTR]

Using a separate amp makes no sense qualitywise.

Yeah, and this is simple and obvious: With any external amp you hardly get the shortest and cleanest possible electric path. Straight from the DAC chip to the headphone amp with nothing unneccesary in between. And the headphone amp is excellent by itself besides the direct connection advantage.

 

[Frank Dernie]

Thank you so much @chips666 for the above guidance. I was trying to find this info and glad you provide such clear steps.

Apologies if this has been asked (still reading through 59 pages here): How does everyone feel about the amp section of the ADI-2 DAC? In hi-power mode, it seems to drive my ZMF Verite Open & Auteur headphones just fine. I think measurement data support the proper handling of the 300 Ohm headphones. That being said, do you guys like the headphone amp in the ADI-2 DAC? On another forum, I learned that virtually no one uses it and they all use external amps.

I am not a big headphone user but if I do listen to headphones I use the ADI-2 Pro I have. I would say it is audibly transparent as long as the 'phones are efficient enough for it to have ebough power.
I use it with Verum 1 (9 ohm impedance) and ZMF Eikon (300 ohm impedance). The characteristic colour of the 'phone sound is way greater than anything a non-broken headphone amp can add IMO.

 

[ezra_s]

...I learned that virtually no one uses it and they all use external amps...

I'm a noone too. Sometimes I get quite puzzled for what people can get to say out there, like if it was some fashion nonsense.

My most "difficult" headphones are the 600ohm Beyerdynamic DT880, with the ADI-2 DAC I rarely ever go to high power level (that was too loud for me to sustained listening) so it seems to me that the ADI-2 DAC has much spare to drive even much harder headphones.

 

[Joachim Herbert]

Thank you so much @chips666 On another forum, I learned that virtually no one uses it and they all use external amps.

I use the RME with Focals mostly, but it has driven Audezes and HiFi-Mans with ease. Recently had a FiiO K9 with THX amp section but returned this because there was no situation where I would have preferred it to the ADI-2 DAC.

 

[3125b]

I learned that virtually no one uses it and they all use external amps.

Guess I'll die then ...