Gone are the days when valve amps sounded like a lush, overly warm and romantic interpretation of the music. These days a typical valve amplifiers circuit is more geared towards a sparkly more dynamic and gutsy type of presentation and the PrimaLuna Prologue Premier continues this trend. This particular valve integrated from PrimaLuna was sent along to Hifi Pig for review from Absolute Sounds in the UK.
The amp looks modern and clean and on the front has just the volume control (ALPS Blue Velvet) and the source selector knob. A valve cage is included to protect the valves from inquisitive fingers and the power switch is on the left hand side of the amp. Around the back is a good selection of four line level RCAs, a home theatre pass through and speaker terminals for 8 and 4 Ohm loads. Inside wiring is point to point. Included in the design of the PrimaLuna is a Bad Tube Indicator which takes the form of a small LED on the chassis in front of each valve and as its name suggests this indicates if a valve is bad. The Power Transformer Protection circuit allows the amp to switch off and reset should the power transformer overheat and there’s a similar circuit (OTP) for the output transformers. In place of a plate fuse the amp utilises a “+B relay” which works in conjunction with the OTP circuit to protect in case of valve failure.
The model we were sent had 4 El34 power tubes and 4 smaller ECC82/12AU7 valves. The more typical ‘old school’ valve enthusiast would take one look at this valve compliment and suggest that the amp would have a large, overblown midrange, soft bass and perhaps a rolled off treble. How wrong he would be!
It’s such a common misconception with valves that they are nothing but trouble ridden unreliable and unnecessary parts of an audio setup – this is also untrue. Yes, a valve can have issues of its own from time to time, but they are far from unreliable in their modern form and with the ability for a user to replace a valve rather than send an entire transistor amplifier to an engineer for repair general maintenance is somewhat simpler in the main. I have personally been using valve amps for a fair few years now and apart from one instance (which a quick valve change solved) have not had any trouble with them whatsoever.
One of the main advantages for me is that the valve platform allows for tube rolling where the valves can be changed to offer a slightly different sonic characteristic and flavour to the music, which is certainly something that cannot be achieved with solid state amplifiers.
The Prologue Premier being all valve has this tube rolling capacity, but taking this notion one step further the PrimaLuna has the ability to configure its Auto Bias settings via the flick of a switch to power KT88 valves and it’s variant a 6550 – as well as the EL34’s (provided for this review) and their variants of KT77 and 6CA7 valves.
Then there are the four ECC82/12AU7 which also have various and different sounding equivalents in modern or NOS (new old stock) vintage tubes, industrial, military and broadcast forms. A minefield you say? No, a fun way to tailor the amp to specific requirements and tastes in that all valves convey slight variations in bass, treble and midrange presentation with some have larger effects than others.
There’s a certain unmistakeable quality to vocals and instruments using a good valve amplifier, a richness of tone, a naturally glorious and beautifully liquid midrange which is both expressive and organic. The PrimaLuna Prologue Premier is one of those valve amps which certainly ticks these particular boxes for me.
The first thing apparent when switching the PrimaLuna on is its cleanliness in the top end. It has a wonderfully sparkly and airy treble which blends down into a clean upper midrange. Details are prominent and easily depicted even when listening to large crescendos and larger orchestral pieces. Dynamics in this portion of the frequency range are not overly strong, they are however far from subdued or mellow and they are a little more energetic and cleaner than natural.
Moving down into the midrange most listeners would agree that this is the strongest area of the sound reproduction with valve amplifiers (and which I agree with) although there are vast differences in tonal balance in this area from amplifier to amplifier. Vocals on the Prologue Premier are strong vibrant and clean in nature, projected and very slightly upfront – which is how I like them. An EL34 tube will always have some added warmth in the midrange and the cleaner circuit on the PrimaLuna allows for a great flavour to vocals. As well as the cleanliness the midrange conveys there is an unmistakable richness to the undertones of male vocals and an organic and natural rasp to the sound which really allows the listener to hear the great vocal range of the likes of Frank Sinatra… or his modern counterpart Michael Buble.
Female vocalists like Rachelle Farell, Ilse DeLange, Mariah Carey and Diana Krall all have a pitch of tone respective to their vocal presentation. Here, although a little bit cleaner than some other modern EL34 amplifiers, upper midrange factors in a bit more forwardness when hitting higher volumes, but at reasonable volumes it’s not as apparent.
Moving along into the bass regions – another common trait of an EL34 amplifier is that its bass is a little fuller, less driven and a little less complex. The nature of the PrimaLuna circuit actually compliments this very well! There isn’t a lot of bloom, there is a tightness compared to other amps such as the Eastern Electric M520 and a simple change of the power valves to the 6CA7 or KT77 would increase pace, drive and lower mid information. Bass as I said is full and it’s surprisingly well extended for an EL34 which is a testament to the circuit used in the PrimaLuna. I would say that overall it was more complimentary to live performances than manufactured music.
Exploring some other aspects of the sound a little further Damien Rice’s ‘Volcano’ showed marvellous timbre to the running of guitar strings to the left hand side of the realistic soundstage allowing both the male and female vocals to sound fluid and engrossing. This is a great late night listening track with great flow and although a modestly stripped down piece of music, the Premier really brings out all the small nuances and finely detailed sounds within the soundstage in a true ‘out of the box fashion’.
I wouldn’t say that there is a great amount of refinement in this amps presentation, although it can convey delicacies which for a bit of soft rock such as ‘The Sultans of Swing’ from Dire Straits allows for the electric guitar to pierce the air and give a bit of an edgy grunt to proceedings.
Of course, being an ardent tube roller I just had to swap out the tubes in the amp and opted for a quad of Gold Lion (GL) KT77’s which bias from the EL34 switch on the side of the amp. I also changed the stock 12AU7’s for a quad of Siemens and Halaske (S & H) triple mica E82CC long plates from the early 60’s. From experience the GL’s should provide more bass drive whilst retaining warmth whilst the S&H will add bandwidth, balance and control.
Switching back on and allowing the PrimaLuna to preheat the valves and do its usual safety circuit checks the differences that could be heard were immediate.
There was a larger bass response which was also tighter and more driven. Midrange gained openness and the silky clean expression of the vocals attested to a more ‘in the room’ feeling with them being more lifelike, less muddy and absolutely wonderful in every way.
Top end was a huge leap for me with the depiction between details and the airy silences really added a more intense and lifelike feel to the sound. Notes were crisper yet more controlled and the detail retrieval seemed greatly improved with added bandwidth and rendering.
Dynamics also seemed to sound freer and came from a darker background which was never overly dead and still allowed for that seductive valve flow to wash across an improved soundstage.
I ended up concluding my time with the PrimaLuna listening to some rock and I’m sure most of you that follow my reviews know this really isn’t my favourite genre, but then I do like a little from time to time. One of my favourite rock albums of all time is the ‘Hysteria’ album by Def Leopard, definitely their best work and with the rolled tubes on board I easily went through the whole album. The amp still retained the previous grunt with the genre that I enjoyed earlier when listening to some Dire Straits and this was truly unexpected. I’m sure some would argue that valve amps just don’t do rock music but I enjoyed it very much with the PrimaLuna in the system.
Accompanied with the amplifier is a seriously sleek ‘wand’ type remote in black metal and with just six shiny stainless buttons. I never touched on this earlier in the review as my example had run out of batteries – probably due to having a button depressed when it was packaged after it’s last review, I never bothered to change the batteries as you need to remove the two rubber rings (which prevent it from being scratched (or scratching) a flat surface and which stop it from sliding about on a table) to reveal a couple screws which then expose the battery compartment. I’m used to having to turn two volume pots on my Emille so one was still an easier solution than normal.
I just found myself holding the remote from time to time and admiring it instead… and playing air guitar with it too from time to time!
I would conclude that the PrimaLuna Prologue Premier’s circuit is highly accomplished and with the stock valves in place it a sounds fantastic. However with a few changes in valve compliment there really is a whole heap of detail, complexity (amongst other attributes) which can be achieved to provide for a really engrossing listen.
With its ability to switch between KT88, EL34’s and their variants via a simple flick of a switch and its non-deadly auto-biasing feature, the PrimaLuna is extremely flexible and should cater to the specifics of most users.
Looks-wise it’s simple, attractive and well made and it comes with that super sexy all metal remote control.
I for one would certainly stump up the pennies for one of these. Have a listen and see what you think and if your already on the valve train and have any of the variants of the tubes mentioned take them along and see if your dealer will let you have a play – if not wait ’til you get it home.
Build Quality – 8/10
Sound Quality – 8/10
Value For Money – 8/10
Overall – 8/10
Price when tested EL34 – £2300 (KT88 – £2600)
Highly recommended for its flexibility, simple good looks and core sonic signature.
Author – Danny Worth