Muso 2nd Generation

I guess it should be possible for Naim to add stereo pairing as an option. Apple do it with AirPlay, but as far as I’m aware, only for their own Home Pod speakers, and others such as Yamaha and Sonos do too. If you want Naim sound quality, though, I’d be inclined to go with the idea of an Atom. Or on a tighter budget, I reckon you could pick up a Unitiqute and a pair of used Neat Iotas for the price of two QBs.

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I was just reading the latest reviews on the Mu-So 2 and came across this quote:

The Naim’s native DAC resolution is 24bit/88.2kHz…
(https://www.stuff.tv/naim/mu-so-2/review)

The native DAC resolution is 24bit/88.2kHz, although the Mu-so 2 is capable of downscaling files of up to 24bit/384kHz via UPnP or wired/wireless network connection, and 24bit/96kHz via its digital optical input.
(https://www.trustedreviews.com/reviews/naim-mu-so-2)

That is a little disappointing since I would be using Roon as the primary source and have fair share of my library in hi-res. It is also a surprise as the Naim website mentions support up to 384kHz (a little misleading) and even:

From 32bit high-resolution streaming to multiroom music to HDMI TV sound; you’ve never heard it so good from an all-in-one wireless system…

While I understand that it might still sound “fine”, for me, and especially considering the cost, it is further cause for pause.

That wasn’t the meaning of the poster.

Do you this information verified by Naim?

I have no idea if it is verified by Naim, but as Naim’s site posted links to these reviews I assume that Naim would have corrected any misinformation.

I assume that Naim provided the reviewers with that info, but I would love to be corrected.

Hi @adeeb and forumers,

I would like to give some clarity regarding how Muso MK2 works, as a true end to end digital active system works differently to a full range single output analogue system.

The Muso system can be seen as 3 processing stages. Streamer engine, DSP that does active crossovers and optimises the signal for each drive units characteristic, then digital modulators that drives discrete output drivers, that finally drive the drive units.

Muso MK2 streaming core can natively accept files and streams upto 384kHz, with a depth of 32bit per sample. We use a dual core 1.2GHz iMX7 CPU for this task which is quite a serious processor. Data format wise it’s either 32bit IEEE float which represents the value of a fixed point 24bit sample value, or a 32bit fixed point value that is actually a 24bit value that is padded to 32bits. We accept all the permutations. From Roon we accept all data natively up to 384kHz and upto 32bit payload per sample which is leading edge for this type of product. The Roon audio chain view represents accurately what is going on and has been certified by Roon labs.

The next stage of Muso is that we have a dedicated multicore DSP that takes this signal and does an active crossover, drive unit management and getting the signal optimised for the class D amp modulators. The DSP does its internal processing at 88.2kHz, using 32bit maths which results in 24bit fixed point samples feeding to the amp modulators. At this stage we don’t process at ultra high sample rates as we know the physical frequency response of the various drive units and the art is to feed each drive unit as optimally as possible - not feed them signals out of their physical operating parameters, or have huge amounts of wasted digital processing in the system.

Finally the DSP output goes through a dedicated multi-channel modulator which drives a set of dedicated class D power drivers and output inductors. This is the stage when the bitstream become analogue and feeds each drive unit. This final stage is similar to how DSD works.

Naturally all the above is quite a science and an art to sound great, but when implemented properly can give excellent performance for the price, as all the components are optimised to work together.

Best regards

Steve Harris
Software Director

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Thank you for the detailed explanation @Stevesky!

While a part of me still would have been happier if the internal DSP was performed at the full resolution, I trust that you had your reasons.

I wonder if in your testing — given the internal DSP rate — is there still an audible difference between feeding the Mu-so 2 music at 192kHz or even 384kHz vs 88.2kHz, assuming the same track and mastering? Also, would you recommend any up/down sampling in Roon for the optimal results?

Thanks again for taking the time!

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Hi @adeeb,

When taking a stream of sample rate x, its often quite undesirable to do all the active crossover processing at some uber high sampling rate. Everything has to work harder = more power consumed = electrical noise floor in the product goes up = typically negative influences in sound… then right at the end of the audio chain, it then has to be all filtered off anyway. In the world of cars, that’s the equiv. of a lot of tyre smoke and very little motion!

As for listening to different sample rates, typically if adding external sample rate conversion stages, the user ends up listening to the filters/distortions introduced in the algorithm, so it’s hard to appreciate what is being listened to and often comes down to personal preference on a given recording. It’s why great mastering engineers spend a lot of time getting downsampled material to 16/44.1kHz to still sound good.

On Muso we’ve spent a lot of time getting the audio processing chain optimal, so the end user doesn’t have to. As a rule of thumb, I would suggest sending the source material over natively to Muso, rather than upsampling it, converting to DSD or similar. Primarily it adds more filters into the audio chain on Roons side and gives the Muso more unnecessary work to do.

Best regards

Steve

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Thanks Steve for explaining a very complicated process in a way that i think i understand👍

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I like to buy Mu so 2 and i have a question:
Is it possible to connect a Oppo BD103d HDMI audio out only and play cd with HDMI connection or is it only for TVs?

Berglake, from what I understand, the HDMI input utilises the Audio Return Channel (ARC) from suitable TVs with ARC enabled HDMI inputs. As such it is not designed to take a regular HDMI audio output from something like a blu-ray player. Probably you best bet here is to connect the Oppo to the Mu-So2 via the s/pdif optical input.

Good Deal Alert - Ex-display gen 1 Musos can be had for £599!!

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I’ve been reading this thread because I’ve long wanted to add streaming capability to my musicless master bedroom. I was introduced to streaming with the Naim Uniti Core with about 1000 ripped CDs to choose from. And I have a Roon subscription I’m not using because the Uniti Core is not Roon ready as I had hoped. The MuSo 2 would give me access to my ripped CDs and to Roon, but did I read that I’d have to use Chromecast? Does that give the best audio quality? I have a vague memory of reading that SQ was suspect in Chromecast.

Is there a way to get Internet radio?

Is there a way to add a pair of speakers to get better stereo separation?

If not, (forgive me, Naim) is there a competing product that does have separate stereo speakers along with the file access and access to subscription services?

The Mu-So and Mu-So 2 have internet radio.

No. If you want separate speakers you need to move up to something like the Uniti Atom and then add speakers of your choice.

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Its a very good sound in any way, you should demo, plus you can access streaming services such as Tidal and Spotify.

I actually use a Mu-so Qb in my master bedroom and that all the sound I will ever need in bedroom. It wakes me up with internet radio and when I want to listen to my music I just stream Tidal. Also allows multi room speaker connection with other compatible gear.

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Like all the new Naim streamers, the Muso 2 supports Roon natively, so you do not need to run Roon through Chromecast or AirPlay. Of course, you still need to run the Roon Core on another device.
It does gave iRadio, either through the Naim app or through Roon.

Anyone knows if the Mu-so Gen 2 analog input is pure analog or it goes through an ADC? Thanks.

The analogue input is digitised by the Muso, the same as it is with the Uniti players.

FWIW I raised this question here (and in the following posts) and there were some responses from the community:

Has anyone had a chance to compare the sound of the Muso 2 to the B&W Formation Wedge?

The only comparison I could find is on What Hifi.