WASAPI ("Enhanced") vs. ASIO ("Loseless") for MQA playback

Hello all,

I have been doing a bit of research regarding the comparisons between WASAPI and ASIO; not necessarily comparing which is “better,” but why I would enable one, versus the other and how that changes the signal path status.

My current DAC, the D70s, has (ASIO) drivers that were provided directly by the manufacturer, Topping.

I’ve spent some time during my listening sessions lowering the preferred buffer size, hoping to hear some substantial changes to the delivery, but it would be minimal (when compared to the WASAPI offering) at best.

Presently, I have my preferred buffer size set to 256 samples, but I suppose that I could go lower, as I’m sure my 9900K is capable of handling the workload.

Now, to my question and how to ask it:

I’ve noticed that when switching from WASAPI to ASIO the signal path changes from “Enhanced” to “Loseless.” I’ve been using TIDAL to access different MQA-based content for the sake of this example. This is relevant because I’m wondering if the MQA format is partially responsible for the signal path change.

For each selection, I’ve made sure to have the D70s as the decoder and renderer.

As a consumer, I see “Enhanced” and imagine a higher-quality output, especially considering the little “LED” indicator becomes a star that’s approaching supernova (when representing “Enhanced”).

I’m wondering if the “Enhanced” status is actually “better,” and why it’s only showing as such while using WASAPI?

Any insight would be greatly appreciated.

TL;DR — My D70s does not show up in the signal path while using ASIO (which is labeled as “Loseless”). However, it’s there for WASAPI (which is labeled as “Enhanced”). I want to make sure my DAC is still doing it’s job as the full MQA decoder.

Screenshots of both signal paths would be helpful.

Ultimately, whatever sounds better to you is the right answer.

Here’s the ASIO sample.

… and the WASAPI. Same song streaming directly from TIDAL.

I may be overthinking it all, but I just wanted to be sure I was selecting the “appropriate” method for proper decoding.

From the “original Roon manual”…

Enhanced signal paths are indicated by a bright blue light. This means that Roon is performing some signal processing steps on the audio… in this instance the MQA processing of the signal.

In this case, Roon is not performing the signal processing the Topping DAC is doing the MQA Decode.

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Your Topping should be doing the MQA decode and should display it on it’s screen. I think that the differences you are seeing due to the difference of ASIO and WASAPI. The WASAPI driver is reporting what the DAC is doing back to Roon, so Roon can display that step in the Signal Path.

As to which to use, use whatever you prefer. My personal preference is to use ASIO drivers if I have the choice.

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A reflection of your dietary preferences :grin:

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I see.
That actually makes a lot of sense when you put it like that.

It seems that I was, in fact, overthinking it.
I just wanted to be sure that the DAC itself was still doing all of the heavy-lifting (for MQA content), despite not reporting (back to Roon) what it was actually doing.

ASIO, it is then.

I really appreciate the clarification.

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OH, thanks, I didn’t even notice, lol. And. yes, I did eat sushi the other day.

Hi, sorry to bring this back but I’m experimenting with the ASIO driver.

All the time I played with WASAPI I got this signal path:


where it indicates that the Topping EX5 is doing the decoding and rendering fo the file.

When I listen with ASIO I get this:
asio
What I Understood from the thread is that ASIO does not inform Roon the DAC is decoding and rendering, but it actually is
So if you could confirm that I’d appreciate it
Thanks!

Roon is unable to receive MQA USB HID information when using ASIO due to technical constraints.

If you have an MQA DAC, bit-perfect playback via ASIO should result in the device performing the MQA decoding and rendering itself.

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In ASIO, Roon isn’t being told what the Topping is doing.

Anything after ‘Roon Advanced Audio Transport’ is what’s happening on the DAC side - so you can see on WASAPI that you have ‘Full Decoder’ post-RAAT. This is Roon being told that the DAC is doing the MQA work. The ‘MQA Authentication’ step is essentially Roon confirming that it is sending out an MQA file.

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Thanks @john and @Ben_Hagens for the response. This is not related to the topic, but maybe you can help me.
I have a keyboard with a volume knob and I can control the volume from there while watching movies, videos or gaming, it’s easier. But in Roon I have to control the levels either from the amp or the Topping. Is there a way to control the volume on Roon via the keyboard?. I’ve tried changing to Fixed Volume or DSP control but I can’t.
Thanks!

I was just about to make a post with the same question.
Thanks for clearing this up not only to op, but also myself.