«Leedh Processing» - The end of analog preamps?

«Leedh Processing» - The end of analog preamps?

In the context of digital music, it seems that an analog preamplifier will no longer be necessary to control the volume.

Controlling the volume at the DAC level produces audible artefacts and therefore wasn’t used in high-end products, until now.

«Leedh Processing» is a highly innovative algorithm for increasing or decreasing the volume level of a digital music signal.

Soulution Audio is an early adopter of that technology. It is now used in their flag ship DAC, the Soulution 760. The sonic result appear to be so good that the Soulution 725 preamp in no longer necessary in the context of digital music.

MSB is following the same path.

It would be interesting to know if Naim is considering that technology, or even has on eye it.


I have no idea what technology is used by Chord to control signal output level in their DACs, but I am not aware of any adverse effect on sound quality.

That would indeed be interesting to know.

Being able to control the volume directly from the DAC (whatever the brand) cuts the price of the system by quite an amount.

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@Thomas when you switch to play your turntable does the Leadh processing still control the volume or does it just work on the streamer.

Leedh Processing lies within the digital processing.

A turntable is in the analog domain, meaning you need an analog preamp in order to modify the volume (output level).

The idea behind the Leedh Processing is to get rid of the analog preamp and control the signal output level within the DAC (in the digital domain).

There was a discussion about this on the Auralic forum (community) in light of Lumin’s adoption of the technology and asking whether Auralic might also adopt it. The thread included a fairly comprehensive reply by Xuanqian Wang (Auralic’s head) explaining why the answer was no. My knowledge of hifi electronics is too rudimentary to assess his reply, but you might find it interesting. And, of course, different considerations might apply to Naim.



Apparently dCS might be considering implementing the Leedh Processing in their products.

I wonder how the dCS Vivaldi would sound if directly connected to the NAP S1 mono blocs.

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Lumin adopted this quite recently to. Most users say its a big improvement over the old volume control.

I read the same kind of comments regarding Soulution’s DACs, and it makes sense : it shortens the signal path. Cyrill Hammer, Soulution’s CEO, said it could slow or reduce their flagship preamp sales (the Soulution 725).

Some people like the sound of having their Naim preamp rather than by-passing the preamp entirely, though I am not sure if that is only Naim power amp owners, or If there are others as well. Others of us happily use Dave, and TT and Hugo without separate preamps. But of course if you have analogue sources you’d need a preamp, unless you have an ADC to feed a digital input (Roll on Davina!)

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This seems great if those who are only using digital sources. I was checking out Soulutions phono stages on their home page just last week and learnt that both their 7-series phono stages also have volume controls. Great for those who are only listening to vinyl. For those of us who listen to both digital and vinyl there is added complexity and expense; having to pay for three state-of-the-art volume controls (in the DAC, phono stage and pre-amp).

Best regards


I completely agree with Hans. In addition, music played through the DVC in my Klimax DS (with Katalyst) does not sound as good as when it is played through the analogue volume control in my Klimax Kontrol. In my opinion, that is.

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I believe Linn doesn’t include Leedh Processing in their DACs.

Not really. Leedh Processing is software and included in DACs. I hardly understand how it could add complexity :thinking:

If you need an analog signal output level control you go for preamp.

If you don’t need it then… you don’t need it.

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Okay…notwithstanding the obvious with the above…

I might just point out that Meridian have been doing this for years. A basic Meridian Digital system was a 500 CD transport and a pair of DSP5000 active speakers. Nothing analogue until the signal hits the DACs (post digital volume control & crossover) in the speakers. And going further, the 562V preamp had a built in ADC which converted the analogue inputs to digital. The 562 could even be fitted with a MM or MC phono stage for your TT. Everything after that, volume control, data stream processing, surround decoding etc was digital until, again, the digital stream hits the DACs in the speakers.

And the best bit? The wiring from “base units” to the speakers is thin coax…goes under the carpets…not a NACA5 in sight :laughing: :laughing:


In order to prevent endless, and uninformed, discussions :wink:

Information about Leedh Processing :

Google for :

“Leedh Processing Lossless Digital Volume control”
(will lead to Leedh home page)

Discussion about Leedh Processing integration by MSB and Soulution :

Google for :

" Soulution, early adopter of Leedh Processing"
(will lead to What’s Best Forum)

I wonder if there is licensing involved here somewhere…

If it can be completely bypassed when using a fixed output you are possibly correct regarding the signal path. However, I am sure there is some complexity, and certainly expense, required to implement Leedh processing into the DAC.

I am not against this. I really think it can be a good option for many people. For myself however, an inbuild volume control in a DAC, streamer or phono stage would make me less inclined to buy the product. Perhaps this is irrational but I do not like waste and paying for several volume controls seems like waste. This is also the reason I am not attracted to the top dCS product packages; up to four expensive boxes with all sorts of connection possibilities when I would rather just have one box with an ethernet input and a one fixed analog output. MSB seems to me to be a better alternative with options for inputs, outputs, clocks and pre-amp capabilities. You can buy what you need. If they now offer Leedh processing so much the better.

Sorry for going off topic.


Interesting! That makes quite an unusual system.

As for Leedh Processing, being software their tech could be “easily” integrated to a large number of DAC designs.

For those using digital sources only, this could be very interesting.

Of course… :heavy_dollar_sign: