After nearly 30 years in my hifi system, the made in Italy jewel amp Unison Research Mood was almost part of the family. But I parted ways with it in 2019, when I had the chance to get an English celebrity amplifier, the remarkable Naim Nait 5i.
My blindfolded advice to those who ask for an amplifier of this level has always been “buy a Naim Nait”. I have been rather curious of testing one compared to my Mood, but sadly I have never had the chance. However, my hifi website of reference, TNT-Audio, has a flattering opinion about the English integrated. Any journal of the sector has great consideration of Naim products. And I have never been wrong in following editor Lucio Cadeddu’s advice before. So when he assured me that a Nait 5i would have been a certain upgrade to my former Mood, I sold the Italian amp and on the very same day it left my home, I ordered a NOS Naim Nait 5i on eBay Germany. It was a practically new specimen, used only a few hours and still under Naim warranty for one year!
One thing that attracted be towards Naim – beside its reputation – was that when in 1991 I decided to buy the TDL Studio 0.5 speakers, the first advice I got was to hook them to a Naim. I think that at the time we were talking about a Nait 2, small and powerful and still revered today. For weeks I had been dreaming of comparing the Naim to other amps of the same level while testing the TDLs I was about to buy. But then I listened to the Mood and brought it home without ever comparing it to a Naim…
And today a more recent English amp by Naim is powering the fellow English TDL pair…
The Naim Nait 5i represents a turning point in the production of the Salisbury-based company. It is the first Naim product not to force users to adopt their preferred type of connection, DIN. Every input on the integrated is now RCA. There is, however, the possibility of using two inputs marked CD and Tuner even with a DIN socket. For the rest, the Nait 5i maintains Naim’s tradition of speed, rhythm, dynamics, precision and tonal neutrality, as well as low background noise.
Another Naim idiosyncrasy is to recommend keeping their amps on all the time for the best sound quality. This is based on the fact that it takes an infinite amount of time to fully charge the capacitors – full charge is never achieved but is getting closer and closer with an asymptotic trend. But this also means that after a few hours, if not less, the charge reached is already very close to total. I have to admit that I realized that the sound of the Nait 5i improves after a while that it is on, but it happens with all Hifi electronics. Of course, the time I noticed it most clearly was after a few days I hadn’t turned it off…
Obviously at Naim they don’t believe in the quality of the speaker connectors as the Nait 5i is equipped with modest inputs that only accept banana plugs. Very simple terminals are provided, to which the cable terminations should be soldered and then covered with plastic protection. I preferred to buy gold plated banana plugs, as I was used to the Mood’s robust binding posts! Another turning point of the Nait 5i compared to Naim’s technical choices is that it doesn’t necessarily need cables with a very low capacitance, otherwise there is a risk of damage to the power amps. To rest assured, I got some used Qed cables at a bargain price. Basically, these are cables with the right geometric configuration: the positive cable must be far enough away from the negative one (they certainly don’t need to be twisted around each other).
At first impression, the Nait’s sound did cause my jaw to drop. Maybe it was true it had only a few hours of usage on it. Possibly it still needed to be burnt-in. But the more I spent time listening to it, the more I liked what I heard. I started to notice that things were better in several aspects: details opened up, more air and space between instrument, more separation, more control and depth in general, even in the lower range. It all contributed to a greater transparency.
Maybe my little enthusiasm of the beginning was due to almost 30 years spent listening to one amplifier’s sound. And the Mood was certainly in need of a recap. Actually I learned from its new owner that when at Unison Research they performed a repair under warranty on the power stage, they had been using cheap components, especially the 4 power stage resistors that should contribute to the transparency of the amp’s performance. Practically, with the Mood I was not able to tell the difference between streaming services such as Spotify and Apple Music versus an original CD (obviously through the same Dac). With the Naim, the CD is clearly the winner. With the Mood, even when I listened to different cartridges I was not able to grasp major differences. I did with the Nait (but let’s keep in mind my Mood was not in optimal conditions). Quality amplifiers sure highlight any issues with certain recordings or hifi components.
Therefore I am no longer in the Mood, the Nait has come…
For a while I nurtured the idea of staying with Unison Research and buying a used Unico to replace the Mood. The prices were a bit higher and in the end I opted for Naim also because I wouldn’t have to add more money. Other more expensive options would have been the upgrade version of the Nait 5i, simply designated with 5i (in italics if you haven’t noticed – so that people often prefer to write 5i-2). Aesthetically it is identical to the 5i except for the stereo minijack socket on the front. Naim’s current basic integrated is the 5si, where performances increase considerably – I could really look at it as a future upgrade, if not up to the Nait XS (the Supernait is perhaps too much for my system). Unless…. 😉
Naim Nait XS reviewed at What Hifi
Naim Nac 120x and Nap 150x reviews at The Absolute Sound