Yes, the analogue inputs are digitised so that they can be used in multiroom setups where the signal is sent over the network to other systems. That all happens before the DAC and preamp stages.
Whatever this means exactly, the product page (Nova: https://www.naimaudio.com/product/uniti-nova) says:
At the heart of Uniti is an audiophile discrete volume control which adjusts level in the analogue domain to a premium digital resolution.
(And of course after digitizing the inputs, the signal is converted back to analog again at some point before it is sent to the speakers)
An interesting thread. For 4 months now I’ve been using a LuminU1 mini with a Chord Qutest DAC. This feeds into my 252/250.2.
It’s very very close. The Leedh volume control on the Lumin app, running through the 252 AV input on unity gain is incredibly close to using the 252 conventionally and disabling the Leedh processing in the Lumin.
It has got me thinking though regards really needing my 252. My LP listening/buying has ground to a halt anyway.
For instance I could sell the 252/supercap/Qutest and Headline/hicap and get a Chord TT2. Not sure how the TT2 would match with a Naim Nap.
So for me the Leedh innovation had really upset the standard approach to pre/power etc. One thing I’m not sure about is how much am I still ‘listening’ to the 252 even on unity gain? I would not know how (if possible at all) to connect the Qutest directly to the 250 to make a comparison etc.
Thanks for reading
Bruce
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The real fair comparison would be, as you said, to connect directly the Qutest to the 250. If really the Leedh processing of the U1 mini can equal or beat the full 252 analog preamp, Naim should worry.
@ChrisSU should answer on how to connect the Qutest to 250( probably a Din/Xlr to rca cable).
That of course would not just be comparing any audible effect of the different volume controls, but also comparing the sound that might be imparted by the 252 compared to no electronics, and affected by how well the Qutest can drive a power amp directly not being designed for that, as well the stated need for a NAP to be driven by a NAC to give its best.
The difference vs Qtest powering directly the 250 is that in OP case ( Bruce) , the Leedh processing is done by the U1 mini.
So the comparison is between the volume control ( Leedh processing) of the U1 vs the analogue volume control of the 252.
If I make no technical error . Or maybe it’s more complicated than that.
The suggestion would compare whether one setup sounds as good or better than the other, of which the volume control is only a part. This is of course what people normally want to do in practice, not bothered about how the VC works - and if the sound is liked connected without the preamp then that may be all that is needed.
Using a volume control as DSP before the DAC does potentially enable the DAC to be connected directly to a power amp Without a preamp in between because signal level can be controlled, though as my previous post noted the Qutest’s suitability in this regard is unknown to me, being different from, say, Hugo or Dave that have output stages designed to drive more than just a preamp.
But one caution: because there would be no mute button, input selector, or volume control between Qutest and power amp, that might normally be used to isolate the DAC if switching it on or off - so always make sure power amp is powered off before, and on after, the Qutest as otherwise it Is possible that switching on or off of the Qutest could cause a very loud thump sufficient to damage speakers.
However:
is not the case as that is not the only difference between the two setups, so it tells nothing about how good or bad the Leedh approach may sound compared to a the VC in the 252.
You would need a 2 x RCA to XLR cable made up by someone who knows the correct pin connections for Naim’s way of using XLR. If you want something inexpensive to try it out, Flashback make one.
Just be very careful to ensure that the Lumin volume settings are correct before turning on, or your speakers could get a nasty shock!
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In my opinion what sets Naim amps and pre-amps apart from others is there is amp and pre-amp philosophy and design . I do think they will part from this since as I said this is what they are known for .
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Ah! Thank you. Didn’t realize.
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Indeed - BTW I think you meant “they will not part”
S
There is perhaps some confusion caused by the use of digitally controlled analogue volume controls that Naim have in their Uniti and NAC-N players. This allows them to display a numerical volume level, which I find much nicer to use than the volume pots in the separate preamps.
There is an optional fully digital volume control in the current separate streamer range, but this is disabled by default as Naim say can degrade sound quality. It was apparently only included in order to comply with the requirements of Airplay and Chromecast certification.
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Thanks for the thoughts everyone. I actually did make that error once. Running through the unity gain on the 252, I had not turned down the app volume and the speakers went VERY loud for a second. Nothing blown fortunately. But generally it works fine.
So using the unity gain, does it completely remove the 252 in an influencial sense? For instance, if you upgraded the supercap to DR that powers the 252, would listening through the unity gain output not reveal any benefits from said upgrade?
I guess I’ll have to organise a special cable sometime. I’ve used flashback before.
Thanks
You arecorrect . Sorry for the typo and confusin it may have caused
confusion
From Leedh white paper:
6 Conclusions
The analysis presented in Section 4 has shown that the alternative approach provides distortion-free volume control (up to a certain level of attenuation) and apparent advantages in terms of information propagation.#
The true lossless DAC volume control is used in Metrum Acoustics Adagio DAC and at least one other. They use analog potenciometer to set reference voltage for the DAC modules (ladder type). Higher the voltage louder the music, lower the voltage quieter the music. Once the volume is set it does not change anymore, unless you change it. The data bits remain the same no matter what the volume is set to. It works for low level listening too. Which Leedh cannot do based on their whitepaper.
No complex algorithms. No digital noise. No Leedh?
Roon labs have also digital volume control inside their sw. Has anyone tried it? Just by turning the option on changes the sound significantly. Some could argue that it changes for best. So by implementing LEEDH would they really benefit?
My old Technics CD player had digital volume control up to -12dB. Did not notice any change in sound quality. But then again i do not listen to it anymore. My father does.
Igor
Even if still fed into an analog pre-amp, it’s exciting to consider that there may be a way to properly attenuate the signal to match high-sensitivity pre-amp inputs, without degradation of quality or adding extra components into the system.
MSB Technology, with the MSB Select DAC II, seems to have developed an elegant, yet expensive, solution : no buffer, no output stage, etc.
It goes directly into the power amp using a proprietary volume control (which is in fact a mini-preamp module).
But I don’t think it uses Leedh processing. Apologies if I’m wrong.
Roger