Qb in the kitchen
Posted by: noname on 11 March 2016
Apologies for this turning the first post in this topic into a blog post but it is intended to be useful to others needing to stream to Naim gear in a location where directly connected ethernet is not feasible. Please share your own experiences of similar situations or setups
I have chosen to start a new thread for those challenged, or potentially challenged, by the issues raised in streaming to a Naim system, such as the new Qb, placed in a location where directly wired ethernet is not feasible and where there are sources of interference to wi-fi connections. For many long-established Naim users, the compactness of the Qb, coupled with its impressive facilities and sound, has led to our first experience of streaming to a Naim box connected over wi-fi in the kitchen where almost inevitably the microwave oven will not be far away.
Several anecdotal reports have already appeared under the Qb in da House topic in the Hi-Fi Corner. I have posted there myself. This new topic is distinguished by not requiring any tomatoes to be on or near any photos of your Qb and is intended to focus on the issue of improving wi-fi network performance and resilience. Please be aware that not everyone posting there has had problems with network connectivity. Your mileage may vary. Please contribute to this thread to let us know.
Some background: Naim have chosen to continue the restriction in the wi-fi support in the Qb version of the Mu-so to the 802.11 b/g (I would say legacy) protocols only. One effect of this is to force the use of channels in the 2.4GHz band. The consequences will vary depending on the facilities and configuration of your wi-fi access point or base station (which might be incorporated into your Internet access router). In some cases, contributors to the other thread have re-enabled support for 2.4GHz previously having only devices which happily connect in the 5 GHz band using protocols such as 802.11 n or ac (which can however fall back to 2.4GHz). Others have recommended using an old base station to setup a separate 2.4GHz wireless network to avoid potential throughput issues with their existing wireless network. The bandwidth allowed by the newer 802.11 protocols is much higher. Naim say that the bandwidth available with the b/g protocols is sufficient to meet their specification for the Qb which is limited 48kHz audio maximum over a wireless network. Over wired Ethernet this can go up to 96kHz or 196kHz audio depending on the format.
The advantage of the 2.4 GHz band is that penetration through walls is typically stronger than at 5GHz but it is well-established that there is a greater risk of interference from sources such as microwave ovens in this relatively unregulated band.
In my own case, 48kHz is fine for listening in the kitchen. In any case, Naim Multiroom is always limited to 48KHz I believe and this is what we mostly will be using there. Airplay is also likely to be limited to 48kHz. We are using an Apple Airport Extreme base station, not the latest, but which supports the 2.4GHz and 5GHz bands simultaneously and 802.11 n as well as b/g. The wi-fi setup on the Qb is very straightforward and pretty soon we were pleased to see a connection shown as excellent in the Apple Airport Utility and were happily listening to iRadio and Spotify as well as syncing with the ethernet-connected original Mu-so in the dining area using Multiroom.
That is, until we used the microwave oven when the sound went off on the Qb, albeit temporarily. The Qb is between the base station and the microwave. My first workaround was to use a couple of Powerline adapters (no, not the Naim meaning of Powerline) to bridge the existing ethernet network segment to a new a new ethernet segment in the kitchen. The data is carried between the adapters over the apartment mains power circuit, incidentally providing a higher bandwidth than the wi-fi connection, but not ideal as it can introduce interference from the unshielded mains cables as well as through unregulated power supplies. Importantly for us though, it avoided the silences while the microwave was in use.
Naim support said I’m afraid that 2.4GHz is the WiFi on the Mu-so – if you want to get it onto 5GHz then you will need to use a third party wireless bridge. 2.4GHz was chosen because as far as coverage is concerned it is much less prone to range and interference issues caused by the fabric of the house than 5GHz.
This led to some confusion as the Qb will actually be, and know it is, connected to an ethernet segment. The idea though is to use a different adapter to allow the existing 5GHz wireless network to bridge this segment to the base station and from there onto the ethernet segment where the Internet router and the other Naim systems are connected. I referred to the potential range issue already, but note that, for this approach to work, the adapter will be in effectively the same location as the Qb and must connect at 5GHz. This means it is only an option where range is not an issue. I knew it is not for us as all my other portable devices connect quite happily at 5GHz in the kitchen.
But what about the claim that 2.4GHz is less prone to interference issues? I have not been told what these interference issues are but they are not those caused by microwave ovens. So I set about finding and configuring a many-years old first-generation Airport Express that supports 802.11 n and managed to reconfigure it in client mode using the instructions at https://support.apple.com/en-us/HT201621. There was some messing about as the Airport Express in fact had to be reset, connected to my existing ethernet segment in order to see it in the Airport Utility on a Mac, and then connected to the Qb in the place of the previous Powerline adapter.
You will see from the screen shots that the Airport Express and Airport Extreme base station communicate and each show the Qb as a wireless connected client. However, you I and Naim and the Qb know it is connected to an ethernet segment. So the Qb turns off its built-in wifi.
The news so far is that the signal strength, as expected, is still excellent and there is no interference from the microwave oven as far as the Airport Express is concerned. The obvious next question is what will happen when I try playing music at 96kHz or above. The answer will have to wait until a later post as I do not normally run a UPnP server giving me a quick way to find out. But I will get round to it.
Qb connected over Ethernet to a first generation Airport Express configured in client mode
The Qb appears to be a wireless client of the Airport Express
And also appears as a wireless client of the Airport Extreme base station.
(No name but over 30 years of Naim experience)
WiFi Interference involving the Microwave Oven ...
... and possibly a cordless phone base station.
The news is that I had an engineer round yesterday afternoon who normally does commercial wiring and appliance testing including microwave oven leakage. If you are new to this topic, I ask you to go back please and read my initial post for the background before coming back here.
We had the Qb playing as a Multiroom client with the Qb in its normal position in the kitchen but disconnected from the Airport Express and so using its internal 802.11g WiFi. Airport Utility confirmed the connection quality as excellent.
As before, soon after starting the microwave oven the Qb audio stopped while the source Mu-so and a second Mu-so happily carried on playing. The engineer used his leakage testing device and found minimal readings all round and close to the seals. The readings dropped to background levels a few cms away.
The engineer was also now intrigued. We tried various things then and I have done some more investigations of my own this morning. I have already sent the details to Naim Support by email but, as yet, have had no response.
The only other route for interference involving the microwave oven is presumably the mains power supply. We tried moving the Qb around, even into the next door dining area but still found the same effect of the microwave oven being on under the same playing conditions - although it might take longer before the sound went off.
We then suspected that the problem could be at the access point end - the Airport Extreme. I realised that we had always had a cordless phone base station nearby. Actually it is the Panasonic premium phone listed as a WiFi client (b/g/n) in one of the screenshots in my first post. The WiFi allows contacts to be uploaded from an iPhone and also allows an app to be run so the iPhone can take landline calls. I took the phone off the base station and moved the base station only about 10cm or so further away. The microwave was still on but the Qb sound came back on.
This morning I tried the Qb in its original position, with the phone moved, but playing directly over iRadio. With the Microwave on, the Qb still stopped playing. I moved the Qb forward and round so I could see the status light at the back and the sound same back on. Looking at the photo again, you will see the isolation switch for the kitchen hob in the corner near the Qb (but remember the Airport Express Ethernet cable was disconnected from the Airport Express). The hob is on the same circuit as the microwave oven so I am assuming that is indeed mains-borne interference. The audio came back on even though the Qb was still plugged into the adjacent mains socket so it must be wireless radiation and not carried over the mains lead to the Qb.
I have an iPad connected to the same wireless network over 802.11b/g/n - hence using n over the same 2.4GHz band. Previously I have reported here having no stuttering at all when streaming to it with it right next to the microwave (heating up my breakfast). Now I can report that it also has no problem at all when held up right next to that isolation switch.
We have no other viable location for the Qb in the kitchen. So I am going to keep my connection via the Airport Express which connects in a/n mode and hence in the 5GHz band.
I am still left wondering why Naim chose not to support 802.11n at 2.4GHz in the Qb. I will never know if it would have solved the problem, whether the cordless phone is involved or not. The multiple and smart antennas associated with 892.11n do not solve all interference issues but they reduce them significantly. All I know is that the iPad connected at 2.4GHz over 802.11n suffers no interference whereas the Qb in the same position, with an otherwise excellent signal, connecting over 802.11g does.
I am now going to concentrate on something else. Like listening to music - or there is always the budget speech!