Volume control in Devialet

[nicoludio]

Hello, not quite sure where to post this since the query applies to both stereo and mono configurations.

Does anyone know how the volume control in Devialet works?  One assumes that it is digital in nature so any reduction in volume would, presumably, be achieved by "chopping" bits. However, most digital volume controls function best within a certain attenuation range beyond which there may be a loss of resolution.  I assume that Devialet must have taken this into account into the design especially when one does not necessarily require the full output all the time; anywhere up to 10 - 30W (a guesstimate) depending on the speaker sensitivity and desired listening volume.

Thanks.

[Jean-Marie]

Yes everything is done in the digital domain. This being said they are using 40 bits floating points which is 32 bits of mantissa and 8 bits of exponent, meaning that they don't loose a single bit of precision on 24 bits whatever is the volume.

[nicoludio]

Thanks. Hypothetically, would increasing the processing to 69 bit (like what another manufacturer is doing) be of any additional benefit?

Also, am curious as to why certain other manufacturers advocate not attenuating below, say, 70% of the maximum volume - is this implementation dependent?

[Jean-Marie]

I'm not a specialist is signal processing and audio, but I'm really doubtful that this brings any real benefits. 32 bits mantissa is already 192 dB. Even with the Dev which is exceptionally with a SNR of 130dB, you "only" need 22 bits. So unless I'm wrong I think that all the theoretical benefits of the additional bits would be masked by the noise floor.