This is a review written by Terry Ellis June 2025.

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Accepting a new reality

HiFi system networking and the many products designed for better networking sound quality is a topic area I have not covered very much. Being brutally honest, I have not been overly interested in it. Maybe that is because I have been distracted by other things or maybe it’s because it seemed simple to me and therefore not as exciting as a new DAC or amplifier. It’s interesting that I have still found myself slowly dipping my toe into the networking “trepid waters”, more through circumstance than active choice, so when Network Acoustics asked me if I would like to review their tempus ethernet switch I was initially hesitant. This seemed like it could be an in at the deep end type of review given the high price of the tempus and I feared I would not be able to them, or you justice with my review of it, without a deeper exploration into the overall topic area.

As it happened, I had to wait several months for a silver finish tempus to be available and that gave me the time I needed to do some exploration into HiFi networking, RJ45 or SFP, switch or no switch and more. I have written four articles on this topic, put hundreds of hours into listening tests all leading up to this review and I am very glad it happened like that.

Tempus

The tempus is a two box networking switch, one for the power supply and one for the switch. Looking at them side by side you can clearly see one is designed, or styled is a better term to be placed on a rack or on furniture with its high quality aluminium casework, made from a single aluminium billet, a very impressive thing. The other box, I assume is designed to be hidden away with its all black, not common acrylic casework.

Look at both from the rear and its pretty obvious which is which and here is the first thing I like about the tempus, its designed with hiding cables in mind. That is the opposite to a normal switch where the cables connect from the front, we don’t want that in HiFi. The tempus has 12 network connection points or outputs so can feed and benefit a large network of products. This includes four SFP outputs and this all seems like a lot for my use case so could be seen as overkill for some I feel.

The outputs are all said to be ultra low noise with proprietary multi stage noise rejecting power filtering, precision clocking and enough horse power to feed a huge system, but still running under low stress to keep noise down to a minimum. The aluminium casework is said to act as a shield that makes sense and the acrylic is said to be non resonant, and that is an intersting one for a power supply.

The power supply is called a “hybrid design” and that can be a little confusing as there is not a detailed explanation for this meaning on the website. I do have the MK2 version here so the latest and greatest one. The power supply is custom designed, said to provide ultra low noise clean power using a multi-stage filtered approach including mains filtering on the input and fancy Mundorf supreme capacitors on its output.

Its hard for me to get excited about the power supply in terms of how it looks and feels but it’s still infinitely better than a generic wall wart power supply we often see. The power supply snob in me can’t help but question why is it not a linear supply? I did ask NA about this and they told me their focus is on the speed of the power delivery but my engineering understanding ends there I am afraid.

I can see some lacking excitement for the price, £4295. There is no hiding that is a lot of money for a network switch, audiophile or not and in my system the switch cost around the same as the music transport and the DAC and some might struggle with that cost relative balance. Clearly the tempus is designed for high end systems and for audiophiles who have invested a good amount of money into their systems where they prioritise performance above all else.  That sounds like a whimsical thing to say but I know lot’s of people with that mindset because it takes one to know one.

Journey so far

By the time I installed the tempus at home I had already tested a lot of different networking things and found that having a switch in my network chain sounded better than not having one. By a switch I am referring to a “cheap” unit I bought from Amazon for around £50, this was just to get me started but with all the connections I needed. Including 5V power so I could use it with a very high quality linear power supply from JCAT that cost around £1500. I hoped this would elevate the performance of the cheap switch or at the very least get the maximum out of it and it seemed to work, I was getting some pretty good results, at least I thought so anyway.  This setup became my reference and is what I would be pitting the tempus against.

For some time I have been using the Network Acoustics muon pro streaming system that is essentially a filtered RJ45 network cable setup. It sounded noticeably better to me than many different SFP cable options I tried recently, including optical and DAC cables. This would allow me to test the full NA best network offering but also to test what offers the better bang for the buck the muon pro ss or the tempus?

I used the tempus in my system for around two months before committing to its review, giving me plenty of time to get used to it, but I was also waiting to have the right system here to do the important A/B comparison listening testing

The right testing setup

I only have one review HiFi system in my small home and that means its constantly changing as products come in for review and go again. I think it’s inevitable that you can feel more settled with some systems than others, so some reviews are better conducted at those times and this was one of them for me. Everything was right, I had great speakers, a great amplifier, I had everything setup in my room sounding just right with most importantly no element of doubt towards the sound of anything in the system. I was fully tuned in and you need that when you are making component changes that could give quite small but still significant audible differences. I have listed the full system at the bottom of the review. I have felt more settled with this system than any other for a long time and of course the tempus was a part of that. How much, I didn’t know at this stage but I knew it was a contributing factor for sure.

I placed both switches in a position where they would be easy to access to make cable swapping fast. I used a soft cloth beneath them to prevent any accidental scratches, I know this does not look the best on camera but please bear with me on this. To make sure the listening testing between the switches was fair I used the same brand and quality of power cable, a Tellurium Q Ultra silver to each power supply for each switch and they were both being mains filtered from the same Isotek Sigmas mains conditioner. The tempus power supply I had already found a home for behind my racks out of visual site meaning you wont see it in the photos but its there. Instead you can see the large JCAT linear power supply I used with the cheap switch, I had to place it on the rack for the testing due to the cabling.

I think I should also specify now that all of my listening has been done using the HiFi Rose RS130 digital music transport so a high end digital music source and all the music I used was streamed from Qobuz

Listening test one: will I switch?

I sat down with an ultra serious frame of mind ready to listen for small or subtle differences, but I needn’t have because the difference between the two switch setups was not subtle at all. I want to say this was a fully one sided affair but it wasn’t, or maybe it was and here is the audio quandary.

I pre organised a selection of test tracks for no specific reason other than I have been listening to them a lot recently. I played them over and over again with the tempus in the system hoping to fully familiarise myself with how they sounded, with a final play of one track over and over again ready to listen for a difference. Changing the cables between the two switches only took about 30 seconds so it’s a quick change and the system stayed on and at the same volume so there is no issue there for testing fairness.

Now in typical Terry fat fingers fashion, after I changed to the cheap Switch I accidentally clicked on the wrong song to play, but the song had already started playing before I realised and the sound of the system changed dramatically enough for me to let the whole song play out. The track was Homie by Joris Delacroix and it’s a very nicely produced electronic track with some good solid bass pretty much from the start. I was expecting the cheap switch to sound harsh or edgy or not nice in some way but that is not what happened at all and at first I thought it sounded better. That is because the Homie track had a noticeable amount more bass and fullness in a way and that is naturally quite a pleasing thing for heavy-ish hitting electronic music. I was aware that this could be a misleading test however at this point I didn’t care because I was really enjoying this song, it seemed to have more solidity or a more forward driving nature to its delivery and this raised an element of doubt in me about to the effectiveness of the tempus, but one song is not a fair test.

I then played the track I had originally intended to, Mercy Mercy Mercy by Steve Morrison, from Live at the basement album. This track has some nicely recorded bass, drums, sax and it has a real vibe, a recorded live vibe but with a recorded in a studio quality. With the cheap switch it was the same again, this track came over with a lot of energy and solidity and the bass was really solid and substantial and I was digging this presentation in the main. It was here where the first chink in the armour of the cheap switch became apparent, the sax that plays back left behind the speakers, yes it had quite a bit of live raw energy about it, but it also sounded a little fuzzy, not as well defined sounding in 3D space and there was less clarity or maybe less space around the player as is it sometimes explained in reviews.

I felt I needed to remind myself of how this track sounded using the tempus so I did so straight after and here was my first big clue to the main difference the tempus makes. With it back as the switch the timing of the music, or the music clarity or its sense of openness or its sense of tight bass definition or all of the above were back to how I remembered. The tempus seemed to wipe away a sense of muddiness over the music to allow me to hear more clearly the specifics of it all and that was great, but this came at the expense of some of the music’s solidity. I did also notice a greater sense of perceived dynamic range extension with the tempus. By this I mean the difference between the sense of the height of the sound stage seemed taller and the bass was less central sound stage congested, it was more open sounding there and that allowed the lower bass notes to stand out more clearly. This track definitely sounded darker using the cheap switch, or less extended in terms of height and the overall sense of sound stage scale felt a little smaller, only by a small amount but a noticeable one.

At this stage it was useful to remind myself of what the switch is supposed to do, its intended to do a “cleaning up” of the network. Someone once described the switches role to me as a power conditioner for your network. If that is the case then less is more, we need to remember that in tests like this, so more “cleaning” of the music has to be the better product because it is not affecting the music signal. The music signal always stays the same, it’s what can accompany that signal or not that is the focus of our attention in the main. However, some personal preference always creeps into listening situations so the solidity of the sound from the cheap switch was in the back of my mind as being something I liked.

I decided to test this more using the track Dune II Suite: Part 1 from The World of Hans Zimmer. This is an unusual track where the main body of the song is what sounds like a big truck or car engine revving up and making all sorts of unusual sounds and they all happen back behind the speakers. I appreciate that description is not selling the track but its quite the experience to listen to on a good system and it’s simplicity makes it easy to listen for differences. With the tempus as the switch there was a lot of small and intricate details in the track, its quite amazing how much subtlety and harmonics and detail there can be in this track that making it a very interesting 1 minute 10 seconds of music or sound effect maybe. With the cheap switch there was more of a mass of sound, much of the subtle details and harmonics I was appreciating was not audible now through the solid mass of it all and again the presentation was darker or less tall and felt more squashed in the middle of the sound stage, so worse. The cheap switch did do it again, it made this track sound really robust and solid and that one attribute I liked.

My take away from this first round of testing was the tempus was clearly very different sounding to the cheap switch and much more so than I expected. It was able to present music with a lot more clarity, a lot more detail, a lot FASTER being the big one here and more insightful into the music’s sound stage, layering and detail. If we are thinking of the tempus as a filter, its removing far more “noise” for want of a better term from the music compared to the cheap switch, however with some slight leaning out of the music, or some loss in mass or solidity to the sound. My brain tells me there is a clear winner here in the tempus and by some margin but it would be wrong of me to call it a slam dunk outright win, so this left me with some element of doubt towards the tempus despite very much appreciating what it was doing.

I had to be careful here to not jump to a conclusion too quickly because I felt it was possible that the tempus might just be allowing me to hear the system more clearly for its good and less good attributes. The cheap switch was possibly adding something or just not filtering as well, with some of it’s “distortion” for want of a better phrase, I was hearing as a clear negative to the music but some as a positive to it. Either way that cannot be a good thing with a switch if its audible.  I knew needed to test this more to be 100% and there was more I wanted to test anyway, I was far from done.

Listening test Two: SFP

Both switches will convert the network signal to SFP. SFP is said to have some technical benefits for a digital music transport, with it needing to do less with the signal compared to RJ45. This could be how you are looking to use the tempus so it was important to test it. Network Acoustics firmly believe their muon pro streaming system is the best connection method for sound quality but I wanted to test this myself, especially as I have a Melco C1-D20 SFP+ cable here that is excellent.  I only have one Melco C1 cable and I was using it as the cable link between the HiFi Rose RS130 and RD160 DAC.  I changed this to a USB connection between the HiFi Rose products so that changed the comparison test a little bit, however it was the same setup for both switches so still a fair test.

I used a different test track this time, You’re my hero by Chantal Chamberland, this is a great sounding song, opening with a nicely recorded sax back left of centre behind the speakers, with piano and more accompanying and quickly your into her lovely vocal. So within less than a minute of the track there is a lot to listen to and I played the song several times to be very familiar with it using the tempus in the system. I then switched the two cables to the cheap switch and inside 30 seconds I was sat back down and the song was playing again. There was an instant difference with me almost hating this presentation. Something was just instantly off with the sax, it sounded glassy and odd in a way and by the time the vocal came in I was feeling un settled listening to this very familiar by now song. It has lost its lustre and the sultry smoothness that was captivating about it, now it was a rougher less polished version of the events especially in the bass, that was now quite poor. This difference was more in keeping with what I had expected in the first listening test and I wanted to work out why I only heard it now?

There was also, maybe more importantly no difference to what I called the solidity of the sound, it seemed about the same, but I felt this track was not the best to test this aspect. I did the same listening test using the Hans Zimmer track and this time started with the cheap switch. The song sounded awful compared to what I was used to, there was almost no micro detail or subtlety in it all, it was just thick and dense with the gruff engine sound sounding quite plain, flat and boring. Connecting back to the tempus, amazingly this time there was a more solid sound, loads more detail, insight and plenty of subtlety, with again the perception of greater dynamic range between the top and bottom of the music.

This was very important as it ruled out the one question mark I had about the tempus from the first listening test and I have to be honest by now the cheap switch was dead to me, I was never going to be able to use that again as its clearly not good enough. This proved to me that even a good power supply on its own is not enough, the switch itself and how that is designed is still important so that was powerful for me to learn.

It quickly dawned on me too that with the SFP connection from the switch to the music transport it’s a “straight line”, so whatever the switch is or is not doing you can hear it very easily and that explained the big difference in what I heard different in listening test one compared and two. In test one I was using the muon pro streaming system as the cable connection which is a filtering system, it had been masking some of the differences between the switches, or really it was making the cheap switch sound better than it is, that was quite powerful to learn as well. I would call it quite a massive light bulb moment for me because it shone a very strong positive light on both Network Acoustics products, the tempus and the muon pro, showing how both make their own difference, but when working together the difference is compounded. I was not happy to just accept this, I wanted to test it more.

Listening test three: Battle Royale

By now I knew the tempus worked and is what I would call a significant difference maker, which for a product that is not even in the audio signal path is really quite an achievement. I now wanted to know, for my own benefit more than anything, what is the best way to connect to the HiFi Rose RS130 transport from the tempus. Would it be the Muon pro streaming system RJ45 cable system (from £2,395) or the Melco C1 SFP+ cable system (£749)? I know both products are excellent and both have a valid argument to be the best choice.

The muon pro is designed to be used with the tempus so it of course makes sense to use it, but the HiFI Rose RS130 only has an SFP input and you have to use an adaptor for it to accept RJ45, so that is not “ideal” for the muon pro. The Melco C1 doesn’t have that issue, it offers the more direct path into the RS130, but it doesn’t offer the additional filtering of the muon pro, its just a high quality straight line cable. There is also a huge big price difference with the Muon pro costing around three times as much so you can see why I wanted to test this.

I chose a different track again, this time I went with Easy on me, by Adele from her 31 album. Why? I listened to it recently and thought it sounded amazing on this system so why not use it. I plugged both cable setups into the tempus so I could quickly change just the network input at the back of the RS130. It only took a few seconds to change between them and that was ideal.

I started with the Melco and I was very happy with how the song sounded. The piano back right sounded very clear and clean leading into Adele’s huge vocal which came through with a lot of clarity but maybe leaner than I expected it to sound from my memory. In fact the whole sound was a smidgen more clinical than I expected but that felt like a nit pick at this point because in the main the track sounded great. I listened to the whole song, then listened to the first 30 seconds multiple times before switching to the muon pro. My first reaction was the Piano sounded slighter larger left to right back in the sound stage and it had a richer sounding palette, a warmer tone, if not quite as crisp for the extreme clarity of the piano notes. By the time the vocal came in I appreciated what the muon pro does really well, it helps to soften off the music just a touch, by there being a more full and rich sound. Adele’s vocal sounded more full bodied and warmer and the bass was stronger and I think that made the song sound a little more special to me, or more enjoyable at the least.

In saying that, I can see some people preferring the Melco for the more precise, more clinical delivery, they might see that as more honest or accurate.For that person keeping a lot of money in their pocket will be a huge bonus too. I would be very happy with the Melco had I not done this comparison, I would not know any different. Now I have done this comparison, I think longer term I would end up choosing the muon pro over the Melco for this use. That has been what has happened to me over the last few months of testing all manner of different things,. I spend time with other networking cable solutions but I always end up going back to the muon pro.

I am really glad I did this test, it puts the debate in my mind about what is the right way forward to bed, at least for now. Both cable solutions are excellent, but you do seem to get a bit more from the muon pro, but it does cost quite a bit more for it.

Listening test 4

For resetting my reference for all of this I decided to lastly go back to nothing, just using the long cat 5e network cable that comes straight from my router into the Rose RS130. All I can say about this test was, I am never, ever, ever going back to that setup. Networking is an area of HiFi sound with a lot scepticism and scathing comments by some, but its become important to me. Much more important now the last three months of testing are behind me. There is no going back after that and that is how HiFi gets you.

Final thoughts

I appreciate this has been a very long review with what might seem like excessive detail. That has been very much on purpose. If you wanted to, you could easily mirror my testing, do it all yourself and see if your experiences match up to mine. I have not hidden anything or done anything unusual here, I think these are easy tests you can do yourself.  With one catch being the cheap switch I bought is no longer available but I am sure a similar designed switch would give you a similar result to make the test fair for you.

The result of my many months of testing I think really paid off for this review. I didn’t just jump in at the deep end with the tempus, I built up to it. I knew that would allow me to appreciate it more, having a better overall grounding or level of experience always does. Maybe there is a lesson in that for you if you are new to this. I am still honest with myself and know my review is missing something very important, a price to performance context.  I have not looked at enough other HiFi designed switches to judge the tempus against its peers and I apologise for that. I have used a number of more affordable HiFi networking products (filters and switches) and none of them made anything like the same difference as the tempus, there is something important in that for me. I think for you, I would suggest taking full advantage of NA’s 60 day full refund policy. You can compare the tempus against what you are using and make your own mind up but I am confident it will do the same for you as it did for me.

While I am giving out advice, what would I suggest you buy first the tempus or the muon pro streaming system if you are now interested to give one of them a go. This is not an easy question to answer. The tempus brings clarity and detail to music, the muon pro brings smoothness and richness so maybe that can help you decide and explains why using both together works so well.

A Special Performer Award is Pursuit Perfect Systems highest accolade and is in recognition of exceptional product performance regardless of price

For the full specification of the Network Acoustics tempus see their website linked here

For the full specification of the Network Acoustics muon pro streaming system see their website linked here

The HiFi system for this review was

HiFi Racks Solid Steel HF 2, 3 and 4- video for them here

Digital source: HiFi Rose RS130

DAC: HiFi Rose RD160 video here

Clock: Matrix SC-1

Preamplifier: Galion TS A75 video here

Amplifier: Esoteric S03.

Power IsoTek V5 Sigmas / V5 Titan video here

Cables: Tellurium Q Statement II Analogue Cable
Power Cables Tellurium Q Silver, Silver Diamond
Tellurium Q Statement II Digital cables
Tellurium Q Statement II USB cable

Acoustic Treatments all from GIK Acoustics video here