Topic: ADI-2 Pro as a DAC for 009S + KGST

Hello, guys.
A month ago I bought RME ADI-2 Pro FS R Black Edition. I like this small box with a lot of functions )
Now I have a Stax SR-L700MK2. But I would like to upgrade them - I am going to buy Stax SR-009S. I like classical music and know that these headphones are good for it. I also bought KGST from Mjölnir Audio (one of the latest model).
What do yo think about using RME ADI-2 Pro with this combo as a DAC? I mean SR-009S + KGST combo.
The fact is that I heard a lot of various opinions. Some people told me that I should find other DAC because RME ADI-2 Pro is not suitable for such combo. The others said that RME ADI-2 Pro would be OK.
But in fact, neither of them used RME ADI-2 Pro with this combo.
Maybe is there someone here who knows all this from his personal experience?

2 (edited by KaiS 2022-11-07 18:21:45)

Re: ADI-2 Pro as a DAC for 009S + KGST

I have the Stax SR-009 and drive it from various amps, using my ADI-2 Pro as DAC.
It’s a great combo, and ADI-2 Pro’s built in Parametric EQ lifts the SR-009 at least one notch up, something few high quality DAC’s can offer.

Tonalities of classical recordings are wide-spread, having a continuous, independent Bass/Treble control at hand (literally) is another plus.


I even have the STAX SR-700 (MK1), in some way it has the edge above the SR-009.
ADI-2 Pro’s PEQ can transfer some of the missing to the SR-009, without I’d had a hard time to decide which one I like better.



If you’re really into classical, I’d suggest to have a look into the new JJ Float QA.
The STAX’ens don’t have the slightest chance here against the ADI-2 Pro / JJ Float QA / QA Power Supply Active combo.

I usually don’t write reviews, but couldn’t hold back:
https://www.head-fi.org/threads/new-jec … t-17087891

Re: ADI-2 Pro as a DAC for 009S + KGST

KaiS wrote:

If you’re really into classical, I’d suggest to have a look into the new JJ Float QA.
The STAX’ens don’t have the slightest chance here against the ADI-2 Pro / JJ Float QA / QA Power Supply Active combo.

Thank you very much for such useful and interesting reply as well as for the link to your review on head-fi.

So do you want to say that I need my RME ADI-2 Pro + Jecklin Float QA headphones + FLOAT QA Power Supply Active Transdyn and such combo will be very good for classical music?
I listen to my favorite music from my Mac Pro. Will it be good for the above combo?

Re: ADI-2 Pro as a DAC for 009S + KGST

KaiS wrote:

I have the Stax SR-009

I would like to buy 009S and they are different than 009.

So do you want to say that Jecklin Float QA + FLOAT QA Power Supply Active Transdyn + RME ADI-2 Pro will be better than 009S?

And even better than SR-X9000? Although X9000 require other DAC than RME ADI-2 Pro.

As I understood you right, I will get the best combination in terms of sound quality / price with Jecklin Float QA + FLOAT QA Power Supply Active Transdyn + RME ADI-2 Pro than with any other combination. Right?

5 (edited by KaiS 2022-11-08 15:22:06)

Re: ADI-2 Pro as a DAC for 009S + KGST

xamax wrote:
KaiS wrote:

I have the Stax SR-009

I would like to buy 009S and they are different than 009.

So do you want to say that Jecklin Float QA + FLOAT QA Power Supply Active Transdyn + RME ADI-2 Pro will be better than 009S?

And even better than SR-X9000? Although X9000 require other DAC than RME ADI-2 Pro. ...

Keep in mind that “best” is a very personal thing, specially with something as personal as headphones.

This is why I usually don’t write reviews.

Just this JJ Float QA / FLOAT QA Power Supply Active ( NO Transdyn !) + RME ADI-2 Pro impressed me enough for an exception.


I never heard SR-009S or SR-X9000, but do own almost every other STAX ever released- they follow a certain “house sound”, I would not expect them to go a totally different path.
At least they are all conventional around-ear headphones, which incorporates some limitations.

JJ Float QA is different, in a positive way, even more so than the Raal SR1a that I meanwhile own too, which has it’s own strengths.


I came up with my suggestion because you mentioned classical as your favorite music style, where the JJ Float QA shines even more with it’s natural reproduction of real instruments and vocals.


All that in the light of:
You need to listen by yourself to decide what suits to you.

Re: ADI-2 Pro as a DAC for 009S + KGST

KaiS wrote:

Just this JJ Float QA / FLOAT QA Power Supply Active ( NO Transdyn !) + RME ADI-2 Pro impressed me enough for an exception.

Thank you again for your reply. You said that you used FLOAT QA Power Supply Active. I would like to choose Transdyn. Do you suppose that it would be better than FLOAT QA Power Supply Active? From the info on the website, I see that it is the best. What is your opinion?

By the way, how did you connect your RME ADI-2 Pro with FLOAT QA Power Supply Active? I think we cannot use XLR and RCA in this case.

7 (edited by KaiS 2022-11-09 09:18:28)

Re: ADI-2 Pro as a DAC for 009S + KGST

xamax wrote:
KaiS wrote:

Just this JJ Float QA / FLOAT QA Power Supply Active ( NO Transdyn !) + RME ADI-2 Pro impressed me enough for an exception.

Thank you again for your reply. You said that you used FLOAT QA Power Supply Active. I would like to choose Transdyn. Do you suppose that it would be better than FLOAT QA Power Supply Active? From the info on the website, I see that it is the best. What is your opinion?

By the way, how did you connect your RME ADI-2 Pro with FLOAT QA Power Supply Active? I think we cannot use XLR and RCA in this case.

Transdyn is an effect processing Tonmeister Juerg Jecklin developed to process his classical recordings.
I have one here, standalone unit, and it has a subtle effect on the dynamics - not bad at all.
I don’t use it in this context, I have to admit.

The one built into “FLOAT QA Power Supply Active Transdyn” can be fully bypassed, so nothing to loose.

https://www.quad-musik.de/images/quad/produkte/float/float-breitformat/FLOAT-QA-power-supply-active-Transdyn.jpg

Connection ADI-2 Pro to Float PSU is 6.3 mm TS Jack to RCA cable, nothing special and no problems here.

8 (edited by xamax 2022-11-08 19:50:53)

Re: ADI-2 Pro as a DAC for 009S + KGST

KaiS wrote:

Transdyn is an effect processing Tonmeister Juerg Jecklin developed to process his classical recordings.
I have one her, standalone unit, and it has a subtle effect on the dynamics - not bad at all.

The one built into “FLOAT QA Power Supply Active Transdyn” can be fully bypassed, so nothing to loose.

Connection ADI-2 Pro to Float PSU is 6.3 mm TS Jack to RCA cable, nothing special and no problems here.

I suppose that I will choose Transdyn.

Sorry for my stupid questions. Do you mean using two unbalanced cables? Each cable should have one end as RCA and other end as 6.3 mm TS Jack? Right? And we use two TS unbalanced outputs on the rear of the ADI-2?

Re: ADI-2 Pro as a DAC for 009S + KGST

xamax wrote:
KaiS wrote:

... Connection ADI-2 Pro to Float PSU is 6.3 mm TS Jack to RCA cable, nothing special and no problems here.

... Sorry for my stupid questions. Do you mean using two unbalanced cables? Each cable should have one end as RCA and other end as 6.3 mm TS Jack? Right? And we use two TS unbalanced outputs on the rear of the ADI-2?

All good - yes, as the Float PSU has unbalanced RCA inputs, it’s easiest to go this route.
https://m.media-amazon.com/images/I/71qKpYPfCfL._SX522_.jpg

Re: ADI-2 Pro as a DAC for 009S + KGST

KaiS wrote:

All good - yes, as the Float PSU has unbalanced RCA inputs, it’s easiest to go this route.

Thank you very much.

11 (edited by KaiS 2023-01-26 17:35:42)

Re: ADI-2 Pro as a DAC for 009S + KGST

My favorite ADI-2 EQs for the Jecklin Float QA, on request.


They are optimized for:

• Listening to naturally recorded music like Classical, Acoustic and Jazz.
• A listening level of about ca. 75 dBA LEQ, that’s neither quietly nor very loud.
For Classical orchestral music this equals about the loudness of the real event, which is quieter than some might think.


Therefore, adjust BB (Bass) and BT (Treble) to taste.
B1 “Q” adjusts sub, the very low bass extension.
You can even combine bands of both EQs, like bass from EQ1 with treble from EQ2.


• The amount of bass and treble depends on the listening level.
If you tend to listen loud (I don’t) you need less bass and treble boost.

• There’s even a little bass-dependency on head-size / ear-driver distance.
My relatively flat-lying ears just very slightly touch the drivers.

• With bass-heavy-, or treble-hot-music, bass and treble can be reduced.

• ADI-2’s “Loudness”-function can boost bass and treble Volume-Control dependent.
When using it this way, bass and treble can be reduced too.

• Same applies if the “Transdyn” is used, that is built into a version of the JJ Float QA Amplifier.


Have an eye on ADI-2’s meters, switched to show “Post FX” or “Dual” levels, to avoid distortions from overload / OVR of ADI-2’s output.
The fitting ADI-2 Reference Levels for the JJ Float QA Amplifier are +4 dBu (Pro) or +7 dBu (DAC).


Harman Bass Extension:

BB: Gain +11.0 dB  F   79 Hz  Q 1.5 Shelf
B1: Gain  +0.0 dB  F   31 Hz  Q 3.0 HiPass
B2: Gain  -1.0 dB  F  125 Hz  Q 1.7 Peak

Extreme Bass Extension and some Treble Boost:

BB: Gain +12.0 dB  F   78 Hz  Q 1.5 Shelf
B1: Gain  +0.0 dB  F   31 Hz  Q 6.0 HiPass, less Q = less sub
B2: Gain  -0.5 dB  F  125 Hz  Q 1.7 Peak
B3: Gain  -3.0 dB  F  160 Hz  Q 2.0 Peak

B4: Gain  -0.5 dB  F 1.60kHz  Q 1.4 Peak
B5: Gain  -2.5 dB  F 5.4 kHz  Q 2.8 Peak
BT: Gain  +8.0 dB  F 10.0kHz  Q 0.8 Shelf
DA Filter ADI-2 Pro (AKM): SD-Sharp

Be aware:

The EQ setup named “Extreme Bass Extension” is exactly that.
It’s meant to play natural instruments or older recordings that don’t contain the huge amounts of sub-bass that often can be found in contemporary tracks.
For those fitting tracks it’s really fun, shifts them at least one decade in the recording history time scale.

For EDM or other artificial sounds it‘s too much, the “Harman Bass Extension” EQ is better suited and avoids hitting JJ Float QA’s limits too early.
“Harman Bass Extension” EQ still has a 3 dB bass boost following the Harman suggestion and extends to 35 Hz.

Best to have EQ Presets prepared and select accordingly.