LAB 12 INTEGRE4 MK2 TOROID VALVE INTEGRATED AMPLIFIER REVIEW

LAB 12 Integre4 MK2 Toroid valve integrated amplifier is a 6799 euros offering that uses the excellent and powerful KT150 valves, though it can use other valves too. It’s an easy-to-set-up and use amplifier that promises to have a very low noisefloor. Stuart takes a listen for HiFi PiG.

I’m a huge fan of the Greek brand LAB 12 and we have several of their products that have found a permanent place in our systems. The subject of this review is their all-new LAB 12 INTEGRE4 MK2 Toroid valve amplifier that uses the excellent KT150 tubes. 

DESIGN AND FEATURES OF THE LAB12 INTEGRE4 MK2 TOROID

The LAB12 INTEGRE4 MK2 Toroid is a Class AB integrated valve amplifier built around a quad of KT150 output valves… tubes if you are American. It’s a push-pull design with a claimed 65 watts per channel into 8 ohms, which places it among the more powerful valve amps on the market — certainly more than enough for the majority of real-world loudspeakers.

Visually, it follows the same understated aesthetic as the rest of the LAB12 range, with a clean, industrial-style front panel available in either matte black or silver finish. The symmetrical layout is neat and unfussy: an OLED display sits centrally, flanked by two matching control knobs for volume and input selection/menu navigation. The knobs have a nice feel to them and the volume pot is motorised so when you change the volume on the remote, you see the knob rotate which is quite a cool thing. The display itself is simple, showing input and volume level without unnecessary distraction. It’s an amp that looks like it’s here to get on with the job in hand.

The chassis feels solid and reassuringly weighty, which makes sense given the onboard toroidal power transformer, hefty output transformers, and all-valve layout. LAB12 has opted for an “over-engineered” power supply — not in the buzzword sense, but in that it’s clearly been designed with stability and current delivery in mind. This suggests an amplifier that should remain composed even when driving more demanding loudspeakers.

On the back panel, things are equally straightforward. There are five RCA line-level inputs, plus a single XLR input – note that you can only use RCA or XLR on input 1 and not both at the same time. One pair of speaker terminals is provided for both 4- and 8-ohm loads. Power inlet is standard IEC.

Internally, LAB12 has stuck with a fully valve-based signal path, with 6N1P small-signal valves handling preamp and phase splitter duties. There’s no onboard DAC, phono stage, or streamer — this is an amplifier in the traditional sense. One box. No extras. 

What you do get is a headphone amp built in with the socket on the top-plate of the amplifier. This headphone amp is a separate amplifier circuit that uses the benefits of the upgraded power transformers on the amp. 

You can get the amp in any colour you like, so long as it’s black or silver.

Biasing is handled by controls on the front panel and you don’t need any other special equipment – very useful. The KT150s are run conservatively, which should help prolong valve life, and the amp features a soft-start circuit to further protect the valves and transformers on power-up…and your speakers. Interestingly, the amp is also compatible with EL34, 6650, KT88 and KT120 valves should you fancy fannying about with the power output valves for a different flavour. 

In short, the INTEGRE4 MK2 is a no-nonsense integrated valve amplifier with real-world power, a sensible feature set, and an emphasis on proper engineering rather than bells and whistles. It’s a valve amp for those who want the sonic character valves can bring, without the fuss that can sometimes come with the territory.

I very much like that the power switch on the top panel is labelled just “music”.

My only quibble about the look of the amp is that new LAB 12 nameplate on the top of the amp. I think it looks cheap and isn’t in keeping with the rest of the amplifier’s design, but that’s just my take on it, and others may well disagree. 

SOUND QUALITY

For the duration of the review I will be using the integre with the XLR input carrying a signal from our Lampizator DAC. Speakers are the usual Audiovector R6. 

On powering up these is a 60 second start up period. Once started up the amp is very quiet with barely no sound coming through the speakers when no music is playing. 

Alberto Dimeo’s God Made Me Funky is a slice of Chicagoesque house and is a decent workout to get started with and get the amp limbered up for the first listening session of the review period. It’s got bass kick and bassline, lots of funky percussion and drums, plus some whoosh effects. The integre does a great job with this track with he bassline being rock solid and easy to follow. There’s also a phase kind of effect on some of the percussion and this is easy to hear with the integre in place. Effects that oscillate between left and right are easily discernible and overall the mix is easy to “see”, with different sounds and instruments staying where they should be. Actually, this is a pretty impressive opening for the integre and you can colour me quite impressed. There’s plenty of scope on this track for it to sound mushy and with a one-note bass, but the integre doesn’t flinch at all. La Bionda’s Sandstorm comes on next (thanks ROON) and I’m immediately struck by the width and depth of the soundstage on this track. I end up spending a good deal of time playing house tunes and I find the amp suits this kind of music really well. There is speed and power where you need it and an overall feeling that the amp just isn’t flustered by this dynamic kind of music. 

One of the things I noted when listening to all the house tunes I went through was the excellent way in which the amp represented the stereo image. This is all pretty obvious on tunes that are created in DAWs, but I wanted to hear how the amp coped with tunes recorded in acoustic environments and with microphones – you know, “proper” music. 

Brad Mehldau’s Schloss Elmau is a piece of piano lead jazz that I assume is recorded in Schloss Elmau, the five star hotel and spa in the German Alps. I’ve got a few records that have been recorded here and all have been excellently recorded. This is no exception and the integre does a great job of putting the listener in that live space – it’s very convincing, even at modest volumes. This latter point is important as there are lots of amps out there that only come on song when they get to a certain (fairly high) volume. The nuances of the piano playing are easy to pull out and whilst I’m certainly no aficionado of jazz piano, it’s clear to hear that this is accomplished playing and the integre doesn’t hide this. Drums and contrabass are a little further back on the stage/mix and whilst they are less forward than the piano, they are both still very easy to discern. The integre is ale to convey subtleties very nicely, indeed and when the power is cranked a little higher, those KT150s do nothing but go louder. They don’t introduce any noise or nasties, just more music with the same kind of feel it had at lower volumes. I get the amp isn’t even breaking a sweat here and even when the song gets a little more hectic, it remains composed and in control. I particularly enjoyed the interplay between the piano, bass, and drums on this track with the integre not masking anything from their interaction. This is a very “live” sounding recording and the amp conveys this very well. I get the same realism and feeling of “being there” when listening to Daniel Hope – Escape to Paradise: The Hollywood Album, with Hope’s violin taking centerstage and sounding very life-like…though I soon fall out with this album when Sting begins to sing.

Listening to Doug McLeod’s Black Nights I’m really impressed at the exceptionally low noisefloor of this amplifier which allows the intricacies and subtleties of his guitar playing to shine through. The steeliness of the strings also comes across very well. Likewise Hans Theessink and his Call Me tune had his subtle guitar playing come across very well, as well as his slightly laidback vocal delivery. Again, the steeliness of the guitar (a National Reso-Phonic, I think, but I’m sure others will correct me) comes across excellently. This sub 7K amp can clearly do detail and even on the end of a 50K or so DAC and with 30 odd grand speakers it doesn’t embarrass itself at all. It’s not got the same kind of power, speed, and attack of our Electrocompaniet AW 800 M monoblocs, but they are the best part of 50K and so the comparison is a but moot. However, had I not been spoiled by our choice of amplifiers, the relatively affordable integre from LAB 12 would do very nicely in this system. 

Warrior At The Edge of Time by Hawkweed came out an incredible 50 years ago (released May 9 1975) and it’s a record that has been played countless times over the 30 or so years that I’ve known the record. The relentless Motorik drumming on Assault and Battery/The Golden Void is clear to follow but given the amount of stuff going on this tune (two tunes, actually) it would be very easy for an amplifier to get confused and present a bit of a mush of sound. As Golden Void opens (these two tracks are always played together live) Simon House’s violin cuts busy through the mix and sounds properly out there with all the effects it hs on it. The sound is jarring, and it’s supposed to be (I think). Now, this may well sound like I’m criticising the amplifier, but had this violin sound being presented as less “incisive” I’d have been disappointed and suggested the amp was muting the top end and getting in the way – it isn’t and it doesn’t. On the Wizard Blew His Horn, the splashed cymbals (effected) come from well beyond the speakers, whilst the poem’s lyrics sit centre stage. Lemmy is quoted as saying “The album was a fuck-up from start to finish. That ‘Opa-Loka’ was a lot of fucking rubbish.” But he wasn’t playing on this track and the bass playing-style (I believe Dave Brock played bass on this track) difference is very clear to hear with the integre. Magnu has the effected (it think its a reverse reverb) vocal right out into the room and it seems to come forward and backwards – what they were looking to achieve in the mix, I think. 

QUIBBLES

I don’t like that name plate at all. 

The cage for the tubes is an optional extra.

The remote is small and easily misplaced, though it’s a very useful addition for those dedicated to couch potato life.

CONCLUSION

This amp doesn’t sound like what the cliche of a valve amplifier’s sound. It is not warm and cuddly, it is not “pipe and slippers”. The integre is a fast and incisive amplifier with power by the bucketload and a sense that it’s certainly in control of the music and the speakers. Detail is fine if it is not achieved by pushing the top end and the integre isn’t doing this, it sounds natural and “right” but it certainly doesn’t try to mask any nasties – it’s a very honest sounding amplifier.

Soundstaging is solid, stable and realistic. Power is plentiful and the amp reacts quickly to dynamic changes in the music. It doesn’t have the same grip on the bass as our reference amplifiers, it was never going to, but I think you would be hard pushed to find a sub 10K valve amplifier that has this kind of grip. 

Overall, I thought this amplifier demonstrated that when valve amps are done properly they can sound sublime, and needn’t cost the earth. I was particularly pleased with how quiet the integre was in use and had I not been able to see it on the rack, I’d have assumed I was listening to a very good solid-state amplifier.

I think there is a fear with some people about putting valves into their systems. They are often finicky and frankly a pain in the arse to maintain, but the integre makes all this pain disappear with its simple biasing and set up. Plug it in, wait 60 seconds for it to go through the start-up procedure and enjoy your tunes. 

I thoroughly enjoyed this amplifier and I’d be very happy to have it in a system. 

I laboured over the award I should give this amplifier, but the truth is I tend to pick out products for review that I know I’m likely to enjoy (that’s why you see so many high awards from me), and I did thoroughly enjoy this amplifier. Its price is reasonable, the finish is good (apart from that new logo plate which I dislike), and sonically it just delivers. It’s built to be highly adaptable in that it’s not flea-powered and should work with pretty much any real-world loudspeakers you care to put on the end of it. With all this in mind, I’m giving it our top award. As I say, I laboured over this bit of the write up of my notes and looked very hard for negatives I could shine a light on, but the truth is there aren’t many negatives to this amplifier and the ones there are are easily overlooked when you just sit and listen to your tunes. 

AT A GLANCE

Build and Features:

Good looking and carries the LAB 12 brand forward 

New nameplate looks out of place

Very nice industrial design

No included valve cage, though I rarely use them, even when included

Nice simple layout on the back with plenty of room

Biasing is made easy

Ability to valve-roll with different output tubes

Sound Quality:

Very low noise floor, almost at solid state levels

Power aplenty

Detailed and incisive

Dynamic and powerful

Value For Money:

It’s the best part of 7000 euros which is a chunk of money, but given that I’ve heard amps cost more and sound worse, I think this is relatively good value. It’s positioned where it sound be

We Loved:

A dynamic and speedy amplifier 

Overall good looks other than the nameplate 

The ability to tube/valve roll, though I didn’t try any of this 

Relatively affordable power valve replacements (a quad of Tung-sol KT150s is about 450 Euros)

Onboard headphone amp for those who use cans from time to time

We Didn’t Love So Much:

No valve cage

Remote is a bit small and easy to misplace – I’d like LAB 12 to produce a proper remote control that can control several of their products at once

Price: 6799 Euros

Elevator Pitch Review: Coming from Greece, LAB 12 have made quite a name for themselves since we first encountered them at the Start Up stands at Munich High End well over a decade ago. They produce honest, no-frills designs based on valve technology. The integre4 Mk 2 Toroid Version takes this design philosophy to a level I’ve not experienced with the brand before and uses the KT150 tube to excellent effect to give an integrated amplifier that is dynamic and speedy in its delivery. The amp is also very detailed through all the frequencies, with nothing coming to the fore to spoil a very balanced delivery. It has grip that takes control of the speakers and delivers powerful and realistic bass, It also has an exceptionally low noise floor that allows details in the music to shine through. If you are afraid of trying a valve amplifier in your system, then the easy set-up and maintenance of this one may well be the one to tempt you to the glowy side. 

Stuart Smith

SUPPLIED BY LAB 12

SUPPLIED SPECIFICATIONS

• EL34, 6550, KT88, KT120 compatible (KT150 from factory)

•Dual toroidal power transformers

• Remote Control

• Large OLED display

• Blue Velvet ALPS motorized potentiometer

• Sophisticated protection and bias monitoring system

• No feedback design

• SRSG® implementation

• Fine symmetry® implementation

• Upgraded noise reduction chassis

• Upgraded output transformers

• Redesigned dual mono topology

• 5mm Aluminum face panel

• Five Years Guarantee