DAC/Amp combo for Abyss Diana MR + active desktop speakers — shortlist feedback

[alienaudio]

Hello ASR members,

Looking for community feedback on a desktop DAC/amp shortlist. I'll try to keep this focused.

Setup context -

Source: Apple Mac Studio via USB, streaming Spotify / Apple Music / Roon
Current DAC: Chord Hugo 2 — being retired due to persistent Apple Mac recognition failures (USB dropouts, won't appear as audio device after wake/power cycle, unresolved despite cable swaps, firmware checks, and Chord's own suggestions)

Headphones -

• Focal Celestee — 35Ω / 105 dB/mW (easy load)
• Abyss Diana MR — 30Ω / ~93 dB/mW planar; Abyss recommends 200mW–1.5W

The Diana MR is the demanding load here. Currently driving it with an iFi GO Blu off USB-C which is not satisfying — looking for something with proper current delivery into a low-impedance planar.

Speakers -

Planning to add active desktop speakers (KEF LSX II LT or Kanto ORA) driven via the preamp outputs of whatever DAC/amp I choose.

Shortlist (in current preference order) -

1. Topping DX9 Discrete
2. RME ADI-2 DAC FS
3. Schiit Jotunheim 3 + Mesh DAC module
4. Topping DX5 II
5. SPL Phonitor X

All five have preamp outputs. Main question is which best handles the Diana MR's current demands while feeding active speakers cleanly. Prefer to keep the system as compact as possible since it will be on my work desk where space is cluttered enough

Specific questions -

1. The DX9 Discrete is my current lean — is the headphone amp section genuinely sufficient for a low-sensitivity 30Ω planar, or does it measure/perform better into higher impedance loads?
2. The RME ADI-2 FS has current limiting (~260mA/channel per the manual) and some users report it feeling dynamically constrained with planars. Is this audible at normal listening levels with a 30Ω/93dB load, or is it a non-issue in practice?
3. The SPL Phonitor X has received mixed ASR measurements (notably the headphone amp section at low impedance). Has this been revisited or is the measurement concern considered settled?
4. For the speakers: any practical reason to prefer KEF LSX II LT over the Kanto ORA when driven via analog RCA preout (bypassing the KEF's internal streaming)?
5. Mac Studio USB reliability — power cycling and device recognition
   
   One issue that's driving this upgrade is the Hugo 2's unreliable Mac recognition after power cycling.
   
   So for any of the shortlisted units (DX9 Discrete, ADI-2 FS, Jotunheim 3, DX5 II), are there known Mac Studio USB stability issues — particularly around power cycling, sleep/wake, or hot-plugging? I haven't found anything in my research but I could have easily missed it. The RME and Topping units are USB Audio Class Compliant (driverless on macOS) which I'd assume makes them more reliable in this regard, but happy to be corrected. The Schiit Jotunheim 3 with Mesh DAC uses Unison USB which Schiit also claims is Class Compliant — any real-world Mac experience with that specifically?

Thanks a lot in advance for your feedback

 

[alienaudio]

One thing I missed mentioning; Chord indicted that they use a custom USB implementation (not Class Compliant) which I feel is exactly why macOS periodically refuses to enumerate it after a power cycle.

 

[staticV3]

Hi @alienaudio! Welcome to ASR.

is the headphone amp section genuinely sufficient for a low-sensitivity 30Ω planar

do you reckon the 7W per channel @32Ω might be an indication?

So yes, way more than sufficient.

The RME ADI-2 FS has current limiting (~260mA/channel per the manual) and some users report it feeling dynamically constrained with planars. Is this audible at normal listening levels with a 30Ω/93dB load, or is it a non-issue in practice?

It's a non-issue in practice.

For the speakers: any practical reason to prefer KEF LSX II LT over the Kanto ORA when driven via analog RCA preout (bypassing the KEF's internal streaming)?

The KEF has phase correction and no crossover dip off-axis thanks to the coaxial design:

 

[alienaudio]

do you reckon the 7W per channel @32Ω might be an indication?

So yes, way more than sufficient.

That answers one question… Thanks

 

[LTig]

260 mA through 30 Ohm results in roughly 2W for the ADI 2 DAC, hence should be sufficient. It would be my choice (using the ADI 2 PRO), due to its great feature set and ultra stable USB connection.

 

[alienaudio]

Based on the feedback, decided to pick up the ADI-2 DAC FS. Surprisingly, all the US dealers (Sweetwater, B&H etc..) show it as 'no longer available'!! I've emailed RME asking for clarification on the product being discontinued/replaced.

Anyone have an idea? Thanks

 

[LTig]

Oops - same at Thomann and our local pro dealer. Maybe @MC_RME can chime in?

 

[alienaudio]

Sent a DM to @MC_RME ... hoping for availability

 

[Mike_Trueman]

I can recommend the SMSL DL400 as a headphone DAC / AMP and you will safe some money. (Yeah i do not use Equalizers)

 

[alienaudio]

Thanks for all the feedback. Dropped the ADI-2 DAC FS since I got no response from RME on purchasing/availability.

Tried out the Topping DX9 and Luxsin X9. Ended up with the Luxsin as it clicked for me.

 

[Mike_Trueman]

Thanks for all the feedback. Dropped the ADI-2 DAC FS since I got no response from RME on purchasing/availability.

Tried out the Topping DX9 and Luxsin X9. Ended up with the Luxsin as it clicked for me.

You can not go wrong with a Luxsin.