Introduction - What is the PrimaLuna Evo 300?
The PrimaLuna Evo 300 is an integrated valve amplifier. I have been meaning to cover one of the Evo family of amps for AVForums for some time now and the circumstances have now come to pass where that is possible. We (perfectly logically) do not look at much valve hardware for AVForums so what is the reason for singling this particular amp out for attention?
As we shall cover, the reason for this is that the PrimaLuna goes a very long way to nullify some of the more widely understood limitations of valve amplifiers via the careful application of modern technology to classic engineering principles. There are features built into this amp that are not widely seen anywhere else and, depending on what you need from an amplifier, it could mean that the PrimaLuna might fit the bill when you had previously assumed that you needed a solid state design.
Of course, there’s no point being dismissive about solid state designs because, at the price, there are some simply astonishing models vying for your attention. The PrimaLuna is £278 more than the Naim Supernait 3; a bulletproof, well featured and supremely capable piece of kit. Why would you spend more for something like the Evo 300? Let’s find out.
Specification and Design
Key to what makes the PrimaLuna so interesting is that it can do two specific functions in ways that have previously been much more fiddly and time consuming than they are here. Before we cover that though, the basic specification of the Evo 300 is worthy of note. The Evolution family of amplifiers is a big one. There are four different levels and examples of integrated amps, preamps and both mono and stereo power amplifiers. There is then a genuinely fascinating valve DAC which is a conversation for another time.
At first glance, the Evo 300 is a conventional bit of kit. It uses a quartet of valves, two per channel for power and features a preamp that uses 6 12 AU7 valves. As standard, the Evo 300 ships with a quartet of EL34 valves for power duties and these will give you 42 watts per channel at 8 ohms at 1% THD - a figure unquestionably higher than solid state rivals but not one that should be seen as unusable. The circuit that these valves are employed in is an unusual one. For starters, it takes power from a large toroidal PSU - something that valve amplifiers don’t always do. This is custom built for the job and pairs up with a custom made pair of output transformers as well. A significant aspect of the cost of any valve amplifier is the cost of the copper being used in it and here there’s both plenty of it and it is being used in a bespoke way.
PrimaLuna isn’t done there either. The wiring between PSU, inputs, valves and output is point to point and done over good quality, Swiss made silver plater OFC wiring. There are some good quality components nestling in there too like Takman resistors and an ALPS Blue Velvet volume pot. Input selection is via relay switching which results in a satisfying ‘clack’ when you change input. This is an ostensibly simple amplifier but the bits that make it are of unquestionable quality.
It’s reasonably well featured too. Five RCA line inputs are fitted, along with a direct input and a stereo preout. Prima Luna makes a considerable play of not fitting DACs to its amplifiers, in part because their DAC technology needs a chassis in its own right but also because they are something that can, not unreasonably, date a product terribly if they fail to meet the ‘of the moment’ specification. There is also an optional moving magnet phono stage which can be fitted to the underside of the chassis and that assumes the function of one of the normal RCA inputs. There is also a headphone amp that offers a single 6.35mm connection.
So far this is normal enough; meat and two veg engineering if you will, albeit with a decent cut of meat and nice vegetables. From here though, the Evo 300 starts to do things its own way. First up, relatively unusually, the PrimaLuna has full remote control. You will need to physically turn it on but once you’ve done that, a supplied remote handset will allow for almost every other function to be accessed. This means that using the PrimaLuna is no more arduous than any of the solid state devices I have written about of late.
Then, the Evo 300 starts to move off in more interesting directions. As standard, the Evo 300 is a push pull amp that delivers the aforementioned 42 watts per channel. It is also equipped to run ultralinear; where the output stage doesn’t switch. This is both extremely inefficient and reduces power to 24 watts. The payoff is the improvement in linearity (amazingly enough) through the midrange so long as the narrower operating envelope isn’t exceeded. Some amps have been able to switch between these two modes so long as the settings are adjusted to allow it but PrimaLuna has computerised the process so that the amp can switch on the fly, including from the remote. As such, the Evo 300 can run in liquid smooth triode mode when you want to listen to a dainty singer/songwriter piece before switching to push/pull for something burlier.
This computerisation doesn’t end there. All biasing that the Evo 300 performs is automatic and if an issue is detected, the amp goes straight into protection mode and flags the offending valve. The valves are less likely to offend though because the circuit is both over specified and under driven. The plate voltage; the actual amount of power being supplied to each valve is 417 volts which is a not inconsequential figure but as much at two hundred volts less than some rivals. This should ensure a longer valve life with more stable performance across that time.
This also gives the Evo 300 a party piece unique to PrimaLuna. For many years, some valve amps have been able to switch valves within the same ‘family’- i.e. a KT88 can be swapped with a KT90 or KT120. Here though, PrimaLuna has taken that idea and run with it. Without having to do anything more onerous than (gently) removing the existing power valves, the Evo 300 can be used with - deep breath - the 6L6G, 6L6GC, 7581A, EL34, EL37, 6550, KT66, KT77, KT88, KT90, KT120 and even the KT150 which is like having four scale models of the Gherkin skyscraper poking out of your amp.
Don’t know what all those valves are? Don’t worry about it and leave the EL34s in place. Want to spend absolutely magnificent sums of money tube rolling? Look no further. It’s very important to stress that power will not significantly increase when bigger and more powerful valves are used because the circuit continues to deliver similar plate voltage but you can alter the behaviour of the PrimaLuna in a way that most solid state rivals can only dream of.
In practice, this means you have an amp that is barely more challenging to live with than a solid state rival. The Evo 300 takes longer to start and it needs more room around it but, for the most part, you could pull a solid state amp off the shelf and insert this one and have to change very little of how you use your system. It is quiet at idle and has a pleasingly linear volume ramp. Furthermore, when you power if off, there are no speaker destroying pops or thumps. Thanks to the full remote control, it’s a doddle to use as well. The footprint of the Prima Luna is actually smaller than many solid state rivals although it is important to note that it is both taller and (at 31kg, a lot) heavier than most of them, with a lot of that weight and height being concentrated at the back.
The PrimaLuna is a no nonsense piece of styling. Available in black or silver, you get an input selector and volume knob on the front panel, together with a headphone socket and three LEDs, one of which shows if the amp is on and the other two showing if single ended or push pull mode is selected. Switches on the side turn it off and on, move it between headphone and speaker outputs and alter the bias range on the valves. Compared to some rivals which really go to town on the styling, the Evo 300 feels almost prosaic but rather likeable for it. An attractive valve cage that does a good job of protecting the valves (and indeed people from the valves) is provided and the build quality is excellent. It goes without saying that the PrimaLuna radiates a lot of heat but the manner in which it dissipates it is well controlled and consistent.
In practice, this means you have an amp that is barely more challenging to live with than a solid state rival
How was the Evo 300 tested?
The PrimaLuna was supplied with a matching Evo 100 DAC, with which it has seen plenty of use, and was connected to a Roon Nucleus but it has also been tested with the resident SOtM SMS200 Neo, Chord Hugo Mscaler and TT2 stack, taking a feed from Roon and an LG 55B7 OLED TV and a Cyrus Phono Signature phono stage connected to a Michell GyroDec turntable with Vertere SG1 arm and Mystic Cartridge. A pair of Franco Serblin Accordo standmounts were supplied but a fair amount of additional testing has taken place with the Focal Kanta No1. Material used has been FLAC, AIFF, DSD plus Tidal, Qobuz and some on demand TV and vinyl.
More: Audio Formats
We’ve established that PrimaLuna has gone to great lengths to eliminate the faff and general impracticality of valves. We’ve also determined that this has resulted in a device that, while not as utterly straightforward to use as a solid state rival, is at least on the same page. The question that follows is naturally, does the Evo 300 still sound and feel special enough to warrant you splashing the cash on it?
Let’s start answering that by setting a baseline. If you stick the Evo 300 in push pull, connect up the Focal Kantas and the Chord duo and play Gary Numan’s Intruder, listen blind and ignore the ten cheerfully glowing valves in front of you, the Evo 300 doesn’t sound like a valve amp, it simply sounds like a well sorted integrated amplifier. The sound is big, confident, possessed of decent low end extension and compelling tonal realism. It does in fact, sound pretty similar to the Cambridge Audio Edge A that lives here for speaker testing. When you simply want gain without excessive character, the PrimaLuna can deliver on those needs admirably (and, it’s also worth noting that 42 watts into a reasonably sensitive speaker like the Focal goes a long way too).
Even used like this, there are some clues that the Evo 300 is not simply a more inefficient way of doing the same thing as a solid state rival. The behaviour of the Focal as it crunches its way through Numan’s latest work is notable. This is not and never has been a cossetting speaker but here, there’s a sweetness to the upper midrange and treble that never distracts from the Kanta’s exceptional soundstaging and detail retrieval but makes it that little bit more fun. Even on music as deliberately mechanical as this, a little warmth and humanity creeps in.
Play something with real instruments and a little more humanity and this perception is only enhanced. The stunning Interlude 1 on Sarah Jarosz’s Blue Heron Suite becomes a collection of tangible musicians performing in a way that makes sense when you close your eyes. With music like this, the PrimaLuna enables the suspension of disbelief when you close your eyes in a way that, even very talented solid state rivals can struggle with.
And then there’s Triode mode. To be clear, the limitations of this setting are clearly noted. Volume drops and the available output is reduced (although, with something like the Kanta at your disposal, you’re unlikely to run out of headroom), bass softens and some of the commendable snap and drive that the Evo 300 shows in push pull is lost. Between 80Hz and 10kHz though, the results are simply gorgeous. Here, the classic ‘valve trade off’ is more readily apparent. This would not be my weapon of choice to play The Fat of the Land but, listening to Matthew Halsall’s Into Forever on the PrimaLuna makes the two hefty resident solid state amps here sound small, sterile and weirdly uninvolving. Your reminder too that the Evo 300 can then be switched back via single remote press to something that will make a commendable go of the Prodigy too.
And, if you want, you can go further. Substituting the PrimaLuna DAC for the Chord Duo and the sumptuous Accordo speaker for the Kanta No1 results in a combination that probably isn’t anything like as accurate as the original test set… but listening to something like Eyelids by Paris Jackson, I’m not completely sure that many people will care. For our more determinedly objectivist readers, the PrimaLuna, and indeed every other valve amp won’t make sense as it begins to create errors that aren’t really an issue with solid state. If you subscribe to the idea of a home listening experience cultivated for enjoyment over warts and all accuracy though, the manner in which this amp does certain things is deeply compelling.
And, just to hammer the point home, owning the Evo 300 need not result in this presentation. Some quick checks with a Chord Qutest as a source and the Kudos Cardea C1 speaker being powered via the push pull setting resulted in a system that absolutely nailed that ‘solid state with a little twist’ presentation that I’d experienced earlier (and with more price comparative components). Ignoring the mechanics of how the PrimaLuna works, there are few products I can recall testing that are so effortlessly chameleonic in what they do. The idea of spending… far too much money... on a new old stock quartet of Svetlana Winged C KT88s and inducing a fraction more bite to the presentation (albeit at the loss of some of the upper register sweetness) would be a hard thing to fight if I owned one.
There are few products I can recall testing that are so effortlessly chameleonic in what they do
- Can sound both gorgeous and very different depending on settings
- Very well made
- Fairly easy to use and live with
- Runs hot and needs space
- Some limits to power output
- Still more demanding to use and live with than a solid state design
PrimaLuna Evo 300 Integrated Valve Amplifier Review
This is one in a periodic series of components where my summary will, for a subset of readers anyway, be irrelevant. The PrimaLuna costs more than some spellbindingly talented solid state amps and makes less power with more distortion while chewing more power. None of these things are in dispute.
Where the Evo 300 shines though is that this is one of the most practical, user friendly and flexible valve amps I’ve ever tested and if you aren’t a full on bottlehead, it can spend long periods of time just being an amplifier and a bloody good one at that. But then, when the drink of your choice is poured, distractions are quelled and you want to listen to a decent recording majoring on real instruments and voices, it still delivers a huge hit of vacuum tube magic. This is an uncommon balance of practicality and sonic fireworks that deals with enough of the foibles of valve ownership to be more appealing than most amps of its type. For these reasons, the PrimaLuna Evo 300 comes Highly Recommended.
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