Line Magnetic LM-518IA Integrated SET Amplifier REVIEW

June 23, 2014
9 mins read


5 Stars

Andy Baker finds himself in an orgiastic frenzy of fantasies about tube-rolling as he luxuriates in the superb sonics of an amp from Guangdong Province.

BY NOW, AND in this day and age, you should have no doubt that China is producing high quality and reliable products for the hi-fi market, whether that be for your favourite English, US or Japanese brand, or from dedicated individual Chinese companies. If you remain unconvinced then you had better check out China’s Line Magnetic immediately.

Line Magnetic’s line-up of valve-based amplifiers, digital players and speakers features the Silver series which runs from the affordable through to the high end (see my review of the marvellous entry-level LM-211IA amplifier), the Gold range and then the more esoteric stuff which includes Western Electric clones and suchlike delightful oddities most of us can only dream lustfully of owning.

Image courtesy of Andy Baker

The LM-518IA sits in the Gold range, so named for its striking carrot/gold front panel and, in this instance, the elegant white painted chassis. One of the many things which impresses me about Line Magnetic – and that fantastic name is definitely one of them – is that in terms of build quality, you almost can’t make any distinction between models. Whether it’s an entry level Silver or an expensive Silver or Gold, they are built like the proverbial tanks and look like they are worth a million bucks. Well, several thousand anyway.

Build & Features

The 518IA is a Single-Ended Triode (or SET) integrated amplifier and it’s based around 845 output tubes – lovely big powerful bottles that they are – giving a modest but entirely decent 22 watts per channel. Two 63P3 driver valves are used along with a single 5AR4 rectifier and the little family of valves is completed by two 12AX7s doing preamp duties.

Yes, you guessed it, this is a tube-roller’s dream amplifier with potential sonic flavour variations aplenty. In fact, New Zealand’s sole Line Magnetic agent, Turned On Audio, supplied the demo unit with two vintage Phillips 12AX7s. The rest were the stock valves but they all sounded wonderful, so unless you already own some treasured, exotic valves, which I’m sure will boost the amp up a notch in sonic performance, don’t feel the need to rush out and buy any expensive boutique jobbies straight away.

Sitting behind the valves in their white coated metal housings are the transformers – one low magnetic leakage toroidal and two wide frequency response audio transformers. All three are carefully handmade. High quality “audio-grade” capacitors and components are used internally with traditional point-to-point hand-soldered wiring. I have nothing against circuit boards of course, but point-to-point just seems to show another degree of love; or perhaps I’m a sentimental fool. The Japanese ALPS motorised volume control is operated with a lovely little solid aluminium remote and the volume knob itself, along with the matching source selector, are beautiful pieces of machined metal. The front facia also features the on/off switch and a window for viewing the VU display. There are three line-in inputs (no phonostage or built-in DAC, as are often incorporated these days), a pre-in so the 518IA can be used as a power amplifier, binding posts for 4, 8 and 16 ohm speakers and a removable power cable. There are also bias and hum adjustment facilities so you can manually check up on bias and also tune unwanted speaker hum to a minimum, and there’s a soft start 30 second delay when you power on to protect those precious internal components from the sudden rush of current. A removable valve cover is included and the amp looks great whether this is left on or removed.

Image courtesy of Andy Baker
Image courtesy of Andy Baker

A full-sized amp, the 518IA will require plenty of room to breathe as the transformers are high and the 845s even taller. I sat the review sample upon a solid granite slab on the floor as it wouldn’t fit in my cabinet. Driving 845 valves requires a bit of grunt, so those transformers are big… and heavy. This amp is a back breaker at about 35kg so if you’re slight of build or feeble of muscle, I suggest you recruit some help for lifting and siting – you may just need it.

This is an absolutely stunning looking amplifier; nice and simple in execution and the build quality is truly exceptional. There was a slight hum from the transformers which didn’t intrude on the music and to be honest, I haven’t heard many amplifiers that don’t hum to at least some degree. My own amp hums and my friend’s Leben CS-600 valve integrated hums.


Once the LM518IA was in place, set up, plugged in, powered on and given time to warm up – a good 30 minutes or so is ideal – my next dilemma emerged: what on earth to play first? The possibilities were endless, but I wanted to make a good first impression. I must confess that my first inclination was towards jazz, but as that seemed a little too obvious to begin with (big glowing valves, low watts, reasonably efficient speakers and glorious mono jazz LPs – who could blame me?) I thought a little harder. As it turned out, every genre I played sounded absolutely gorgeous and I needn’t have worried. My Reference 3A speakers are approximately 90dB into 8 ohms and, as expected, there was not a single issue with the 518IA driving them. The pairing made music sound rich, full, powerful and room-filling. Love at first listen? When I finally decided on some music, you bet it was.

With Wilco’s ‘How To Fight Loneliness’ from their excellent Summer Teeth record, my room was filled with smooth and vibrant music full of detail and luscious textures. The organ had an ethereal feeling and there seemed to be an extra twinkle to the piano keys. Bass was nice and chunky, sounding more live and real somehow, which was also the case with the drums and cymbals to which there was an added dimension of detail; like they had been focused to highly clarified accuracy. Jeff Tweedy’s acoustic guitar strumming was delightful and his voice sounded clear and natural with an “ultra-present” quality as though I could have set my dog on him (she would have sniffed him then wandered off to search for cats).

The Line Magnetic fired clean, controlled music out of the speakers with great speed and rhythm and an ease and musical naturalness that made me blissfully ease back into the couch and yet, perhaps paradoxically, were I of a certain, perhaps more lively, inclination I may have been up making silly wiggly movements around the living room and embarrassing the children.

I have a few older reggae and dub records in my collection (Junior Murvin, The Upsetters, King Tubby) and while they may not exactly sound “audiophile”, through the Line Magnetic their grooves were infectious, bass rich and fulsome with highly engaging rhythm sections. My copy of Scientist’s thrilling 1981 record Scientific Dub was next on the turntable – which seemed appropriate really, given the delightful rendering of analogue recording gear and variety of fiercely glowing tubes on the cover. The layered, blazing sound of the first track ‘Drum Song Dub’ featured great tonal balance where the treble was clear and crisp – as evident with the pin-sharp percussion on display – and the bass line fat, jaunty and addictively rhythmic. Around about the upper bass I detected a tinge of not-unwelcome warmth which added a more organic feel to the low end rather than the usual hi-fi-like slam; it was rich but without sounding flabby. Warmth is a characteristic usually attributed to valve equipment – an over-and sometimes wrongly-used description (or assumption) – but ‘natural’ is definitely the best word I can use to describe the 518IA. It definitely doesn’t fit the usual stereotype.

Pitch Black’s Rhythm, Sound and Movement – Rude Mechanics Remixes was another triumph, with heart-stopping dynamics, engaging bass, swathes of florid sounds and rhythms emanating from the speakers in all directions. At one point it seemed to reach right around behind me, and I could hear the trail of sound as it left the speakers. The bass was solid, powerful and well controlled, surprising me with the depths it reached (I discovered another picture on the wall that needs to be better secured).

Deciding to see if the LM could handle something heavier, I fired up my tube-buffered MHDT Labs DAC and selected from my computer’s hard drive a recent discovery. This was English metal band Valfader and their EP Whispers Of Chaos. Valfader combines the best of Mogwai-like soft-loud post rock with Slint’s epic aeroplane-taking-off-in-your-skull note stretching and their own brand of hard and heavy riffing. The instrumental title track starts all post rock noodling, but several exciting tempo changes later is a fully exhilarating metal assault of ‘80s proportions, with spacey hints of psychedelia. The delivery via the Line Magnetic was speedy and action-packed – the drumming was weighty and powerful and the guitar and bass riffing breath taking. Not only did the sound extend into the room with lifelike scale but the room seemed to extend into the imaginary plain created by the loudspeakers. I liked the way the LM518IA conveyed a sense of realism and presence to performers – whatever I happened to be listening to – gently easing space between each instrument and each individual note and coaxing more definition from all the little details that emerged.

Keeping with the heavy theme, the 518IA brought new life to Black Sabbath’s Paranoid (Rhino Records 180g vinyl reissue) with powerful punchy drumming, thick slabs of sludgy bass and vivid blossoms of electric guitar riffs and solos. Hearing the way notes and chords were coherently struck from the strings brought new depth to how I listened to these songs; I was excited by the riffing and the sharp solos but I found I could also listen to chord structures, harmonic sequences, and everything fitted together compellingly. A lot of this music is pretty simple stuff, but it is still clever. The rhythm section had a lush creaminess yet retained that raw, blistering power which rightfully keeps them their place in the hard rock/heavy metal history books. Ozzy’s distinctive vocals reached exhilarating highs with delirious and sweaty ease, sounding as fresh as if the album was recorded only yesterday. Give the man his dues, he can sure wail.

The Oscar Peterson Trio’s sublime little album We Get Requests, and specifically the track ‘Goodbye JD’ was lush and spacious, delivered with lightning quick pace and fast, stunningly detailed transients and notes had well defined leading edges with great body and decay. Peterson’s piano was some sort of intoxicating liquid – pouring like golden champagne from the speakers, both his hands clearly heard playing the keys with satisfying timbral accuracy and an effervescent agility. The rhythm section sounded totally groovy, proving to be the perfect vehicle to drive along Peterson’s swift playing, providing good strong bass action and lively, colourful drumming – both of which succeeded in creating a vibrant and energetic execution of the song.

Listening to hi-fi gear, for me, is listening to the way instruments and notes, melodies, harmonies and rhythms interact and react with one another and the environment in which the music was recorded; the layers, shadings, textures and colours created by a bunch of people and their instruments. This includes the warm tones of a good bass line, the percussive tickling of piano keys, the swagger of a rhythm section or the grit and soul in a singer’s voice. The LM518IA allowed me to listen like this without even having to think about it.

This amp is transparent, has a huge soundstage with brilliant imaging and exquisite detail (most often, instead of thinking ‘I haven’t heard that before’ it was more like ‘I haven’t heard it like that before’) but all that was such a given as to not seem to be as important as the pure naturalness of the sound which was allowing me to hear instruments sound tonally as they should. The Line Magnetic has a way of transporting the listener into the realm of the musician and his or her instrument – it is pure escapism.


The LM518IA is not only beautiful to behold (though I did hear of one visitor to the house asking what the hell it was), it is beautiful and magical to listen to. This amp sounds natural, sweet and inviting, remaining completely unfazed by whatever music it is subjected to – metal, jazz, bass-heavy electronica all sounded totally amazing. Sure, the price tag is hefty but it is well worth every goddamn cent and for most (sane) people it will be an amp for life.

It drove my modestly sensitive speakers with ease and will be right at home with a wide range of speakers. Vinyl is my number one source but digital music sounded amazing in its own right. Whether I was playing high-res FLAC files or streaming lower quality internet radio, the Line Magnetic brought music to life and took my senses and emotions on a colourful and thrilling journey, miles from the usual day-to-day trials of life.

As mentioned, I think tube rolling is to be encouraged but is not entirely essential, at least not at first – for who couldn’t resist tweaking and experimenting with those little “living” glass beauties? So sit back and enjoy the music. Remember I mentioned my friend’s Leben CS-600? Seriously, the Line Magnetic is in the same league, and if you’re in the market, with that kind of budget, it’d be well worth a China vs Japan shootout – though it could be too close to call.

If you still remain unconvinced that such a good piece of audio equipment can come out of Guangdong Province, then you are doing yourself – and your music collection – an absolute disservice. ANDREW BAKER


  1. Really a great Amp! I have 2 sets of LM tube amps, it really made my daily life fulfilling .

  2. Bjr, cette amplificateur hifi m’intéresse, j’aimerais savoir le prix,et s’il y a la possibilité d’être livrée en Guadeloupe.

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Give a little to support Witchdoctor's quest to save high quality independent journalism. It's easy and painless! Just donate $5 or $10 to our PressPatron account by clicking on the button below.

Witchdoctor straight to your inbox every 2nd week


Advance Paris - Designed with French flair. Amplifiers, Streamers, CD players and more
Previous Story

Ghetto Sunrise – Ghetto Sunrise (Independent) ALBUM REVIEW

Next Story

Um.. – yeahyeahabsolutelynoway! (Rattle Jazz/Ode) ALBUM REVIEW

Latest from Amplifiers

Go toTop