Leedh Processing - Perfect Digital Volume Control?

[David_Gibson]

Just curious how many people are using digital volume control. I have two setups, my office rig is sitting right next to me so I just reach over and turn the knob. My music room amp has a remote. So, with the exception of a couple of Sonos speakers, I never use digital volume control. Considering the sound quality of the Sonos, the volume control has no effect.

[wklie (Peter Lie)]

Assuming Roon DSP engine and volume leveling are turned off: with Lumin running RAAT, Roon Core tells the Lumin endpoint the volume value to use via RAAT. Lumin then applies its own digital volume. In this scenario Roon 64-bit volume is not applied.

[AndersVinberg]

Peter provided a link to some documents, I commented, but there are two threads going. Here is my note in the other thread:

LUMIN Music - Leedh Processing

Thank you. That helped, a little. I’m not really convinced (not having heard it). I have worked in computer graphics, initially with floating point math on big computers, but when the PC arrived it all became integer math because that’s all the CPU could do in real time. And that lead to a generation of engineers who thought that a line had to be an integer number of pixels wide. But that is clearly wrong, it leads to limiting decisions for algorithms. In a grown-up product like Photoshop, it …

[Stef_Dahl]

I do not have a lumin and I use an RME ADI-2 DAC which has a volume management by remote control (DSP inboard) but not manageable by Roon.
On the other hand, I use the Roon autolevel to avoid differences in levels (> 18LUFS, especially with Roon radio)
I asked the question because if Leedh processing was superior in quality to Roon 64b float, it could replace it.
2 things: if the superiority is demonstrated and if Roon … agrees to pay the license.

[Elmar_Heimes]

@wklie

Assuming Roon DSP engine and volume leveling are turned off: with Lumin running RAAT, Roon Core tells the Lumin endpoint the volume value to use via RAAT.

What happens to Leedh processing, if I actually DO have the DSP engine on (for room correction)? I am tempted by Leedh, but would not want to give up DSP …

[wklie (Peter Lie)]

Roon Core will perform DSP first. After receiving music data via RAAT, Lumin will perform Leedh Processing Volume.

[Elmar_Heimes]

Thanks, Peter! That helps.

[Elmar_Heimes]

Referring to the title “Perfect Digital Volume Control?” I would have to reply with a resounding “YES!”
As it is these days - I had quite some time available for tinkering with my system and so I activated Leedh on my Lumin D2 (with LPS) and took the pre-amp (Pass XP-10) out of the chain.
I did not really expect much from the change (especially after a few hickups in the beginning, which were entirely my own fault), but what can I say …?
I was totally blown away by the difference in sound!
What followed may be a bit exaggerated, but I actually bought an X1 and put aside the D2 and XP-10 for sale. My system now sounds better than I would have ever thought possible and I am absolutely stunned by the difference!
And no: I am in no way affiliated with Lumin.

[alec_eiffel (Rémi)]

Super! what is your amplifier?

[Elmar_Heimes]

Bel Canto Ref 1000 monoblocks feeding Magnepan 3.7s.

[Elmar_Heimes]

There is a new way to control Leedh processing volume (and all of Roon) which I have tried and am super-impressed with.
Details can be found here:

Microsoft Surface Dial Integration PLEASE!

Dear folks interested in the Microsoft Surface Dial as a Roon controller. Here it is: The rooDial image for the Raspberry Pi zwro w. Please visit my homepage and at http://rooExtend.com Buy a Dial, and a Raspberry, download the image and have fun with your new gadget. It is easy to setup, works like charm and enhances your roon usage so much!

It works like a charm with my X1!

[Tuckers (John H)]

I would love to try Leedh processing with Roon. Has anybody at Roon tested this to see if it is better than Roon’s own algo??

[grizaudio (Stephen)]

A review and measurements of Roons volume control. Why would you need more than transparent?

https://www.audiosciencereview.com/forum/index.php?attachments/whitepaper-roon-dsp-volume-measurements-pdf.131355/

@Extracted from article

Conclusion
The DSP volume control inside the Roon Bridge is as perfect as can be.
The noise floor remains at -178dB, regardless of which attenuation is set for the DSP volume.

This means that even at volumes down to -50dB the dynamic at the output is higher as the signal to noise ratio of the best DACs and power amplifiers. No other issues like intermodulation artefacts between the two frequencies or other distortions have been found. The dither is very well done with a completely flat response.

My conclusion is that there is nothing at all to worry about DSP volume in the Roon Bridge. No analogue volume control in the word can deliver these results. The thermal noise of a potentiometer or an analogue ladder attenuator will be much higher than the -178dB the DSP volume control of Roon delivers.

[Henry_McLeod (Henry)]

Nothing wrong with choice. But I’m pretty sure you can be transparent while choosing linear, logarithmic or some other response.

[David_LAw]

I am Using Leedh volume fantastic ! I set a Topping pre to 0 (unity gain) and bought the Lumin Remote. There is a difference in detail, soundstage and dynamics.
Room volume via this. Simple and easy giving great sound.

[David_LAw]

Buy the Lumin Remote. This is expensive but much less than many spend on cables. I have a Lumin remote and not only is it functional in many ways but looks and feel beautiful.