• AddThis Social Bookmark Button

Air Tight ATC-1 Preamp and ATM-1 Power Amp Reviewed


  • February 13, 1989

| Print Page | Adjust Font Size:

Free Home Theater Review Weekly Newsletter.

Enter your e-mail below to get Home Theater Review's weekly newsletter with the latest equipment reviews and home theater news sent directly to your inbox.


*Required

Never, if you value your sanity, thumb through a Japanese hi-fi
magazine. If you're an inveterate hi-fi casualty, the pictures
you'll see will haunt you the way a girlie mag tortures Adrian
Mole. I never take my own advice, so I pore over these exotic
journals whenever they come my way (hi-fi and girlie). And for
the past four years, I've been waiting impatiently for a stab at
the electronics from Air Tight.

I admit that the charm of the name, the absolute perfection of
that moniker for a brand of valve amplifiers, caught my attention
as much as did the obviously exquisite manufacture. The price,
too, appealed, considering that these amplifiers promised
peerless construction and attention to detail you just don't find
this side west of a Jadis. At last, there's a UK importer, so my
wait is over.

If my assignment sheet is correct, this will be appearing in one
of our High End specials, which means that I'm allowed to wax
lyrical about stuff that's impractical/over-priced/exotic/bizarre
and un-Quad-like without fear of censure. Okay, gang, this is it:
Air Tight has produced what has to be the audio equivalent of a
Faberge Egg.

The ATC-1 Valve Control Amplifier and ATM-1 Valve Power Amplifier
contain all of the right ingredients for rampant audio delirium.
The product descriptions read like a menu for a hi-fi bacchanal,
especially if the diner has a craving for vintage, uh, vintages.
Common to both units are PCB-free circuits, with everything
hard-wired a la Golden Age hardware or our own Croft products.
The valve bases are ceramic, with gold-plated sockets. The
chassis are copper plated and the gorgeous, grey 'almite
treatment' faceplates are machined from 8mm aluminum. All of the
valves are genuine brand-name items, like Siemens and Pentalab
rather than whatever-you-can-get throwaways from China. They're
the closest things to jewelry that this industry has produced,
in terms of finish, appearance and attention to detail. In other
words, they've been assembled with the kind of fanaticism you
find only in Tokyo or Teheran.

The preamp is deceptive because it's so petite, measuring only
430x90x325mm (WHD). As with Counterpoint and other makers of
slim line valve preamps, Air Tight mounts the five 12AX7s (ECC83s)
horizontally. And as with Lux, who couldn't resist mounting the
valves on the front of their hybrid 'Brid series integrateds, Air
Tight mounts three of the little beauties so that they can be
seen from the left-hand side of the case. The gorgeous front
panel provides source select for phono (m-m only), tape monitor,
mono/stereo select, attenuate (full muting), balance, volume and
on/off, plus an orange tell-tale. The controls are among the
smoothest, most luxurious I've experienced, but I must resist the
salacious adjectives which come to mind.

At the back, all is gold-plated, with inputs and outputs
corresponding to the front controls, but with two extras. In
addition to the main outputs there's a spare set for feeding a
second power amp and a pair of sockets tagged 'EQ out'. The
latter takes the phono signal from input through RIAA circuitry
and straight out again, for feeding directly into the ATM-1 power
amplifier, bypassing every unnecessary switch and stage in the
preamp. This can be used in tandem with the standard outputs for
some curious purist combinations.

The circuit itself is based on vintage concepts, just like the
PCB-free construction, and consists of a three-stage
low-impedance equalizer described as 'once employed by the
Marantz 7'; this is the stage fed straight to the EQ Out sockets.
The single stage line amp is devoid of tone controls or filter
circuits and features low-impedance cathode follower output. The
power supply employs a solid-state ripple filter circuit for
suppressing mains hum and noises. Despite the size of the
enclosure, which would suggest the use of a compact toroidal
transformer, Air Tight opted for an EI core type because it
provides 'sharper attack of sounds'. The cores are wrapped in
silicon steel plate and copper plate to ensure perfect shielding.
The power supply, phono and line stages are totally independent
and the latter two are fully shielded. The chassis was made
deliberately heavy to help minimize vibration and component
interaction. All tubes are pre-aged and fitted to the
aforementioned gold-plated sockets in ceramic bases.

The ATM-1 power amplifier is based on Mullard research and
employs four 6CA7 output valves from Siemens for a rated output
of 36W/channel. For protection to the output tubes, Air Tight
uses 5AR4 in parallel at the rectifying stage instead of a diode,
to better cope with large current. (I don't have my RCA or Babani
guides handy, but I think they're equivalents to the GZ34 in my
cherished Dynaco...) The output transformers, deemed by many
current amp builders as harder to find than good tubes, are the
highly-rated Tamuras, used in the Japanese broadcasting industry.

Air Tight operate the amplifiers for 100 hours before they're
'retuned' and dispatched. Aside from a valve cracked in transit,
these piece have proven to be the most trouble-free and ghostly
silent tube products I've used in recent memory. It also explains
why Air Tight insisted on air-mailing to me a selected 12AU7
rather than risk any sonic compromises from my probably iffy
stock of mystery brand tubes.

The amplifier features a bit more than the minimum socketry and
on/off switch. Across the front are two sockets and three rotary
controls in addition to an on/off button and tell-tale to match
the preamp. The sockets accept a CD player straight in, while the
first rotary chooses between the front panel inputs and the main
inputs at the rear. The other rotaries are left and right volume
controls for the source fed in via the front sockets. These
sockets, by the way, bypass certain parts of the amplifier's
circuitry, connecting the input directly to the first stage
valve. At the back are the main inputs and the speaker terminals;
the arrangement with the front panel 'front/rear' selector allows
purists to feed the CD player into the front sockets, with the
preamp and therefore the other sources left permanently installed
at the back. Naturally, using the preamp in its EQ Out mode for
optimum phono playback would require the use of the front sockets
and hence the volume controls.

My only complaints about the presentation involve the diabolical
speaker terminals, those daft constructs which only accept bare
wire. Considering the prices of these units, I would imagine that
importers could specify something a bit more practical for the
models they're importing, like Michell or Monster multi-way
binding posts. Anyway, there are three terminals per channel
rather than two, which allow for the selection of either four or
eight ohm operation.

(A couple of other details of the review samples will probably be
changed when regular stocks start arriving. These include
three-core, blue/brown/green-yellow mains wiring, the blocking
off of the extra two-pin mains outlet and the provision of a
grill or cage to cover the valves and protect them from prying
brats.)

I used the Air Tight combination with the Oracle Delphi II
turntable, SME V tonearm and Audio-Technica ART-1 cartridge, the
Marantz CD-12 CD player and the Sonus Faber Electa Amator and
Celestion SL700 loudspeakers, with a variety of wires including
Master Link, Mandrake, Lieder, Sony LC-OFC and Monster M1. And I
immediately hit on two mismatches.

Trying to think like the kind of anachrophile who would have
designed these items, I'm assuming that the company anticipated
use with high-output vintage cartridges like Deccas or m-cs like
Ortofon SPUs with onboard transformers. Sure, I could get some
sounds, but headroom and maximum level were in short supply, so I
did my 'quiet' listening with the ART-1 fed straight in and my
head banging with the Classic step-up in place. The other mismatch
was the Celestion SL700, which needs more juice than this baby
can muster. Again, I could get some positively dandy sounds out
of the '700s, but bo way would it cope with the odd crescendo.
But because sound -- if not the levels -- was so enticing, I
spent as much time driving the '700s with the ATM-1 as I did the
easier Sonus Fabers. Thinking like the Japanese, though, would
suggest that most of these will end up driving some
hyper-sensitive classics like Lowther horn systems. Mind you, I
had so many combinations to try out, what with the bypass mode
and the CD Direct inputs, that I stopped worrying about it and
treated the reconnections like a daily chore. Like shaving.

Fortunately, the long build-up between the time I first learned
of the Air Tight and the first listen was rewarded with some of
the mostly gloriously lush and musical sounds I've heard since
running an SPU into elderly Marantz and Dynaco tube electronics
through the AR 2AXes. Talk about a blast from the past...
Actually, that's unfair, because the preamp sounds 'younger' than
the power amplifier, most of the Mills & Boon effects coming from
the ATM-1. As I tried the preamp with the Aragons into the Divas
and drove the amplifier both directly from CD and with the Audio
Research SP-9, it was easy to attribute characteristics to the
pair's respective halves.

What both share sonically are ghostly silences by both valve and
solid-state standards, phenomenally wide and open sound stages
and absolute freedom from edginess. But while the preamplifier is
detailed and precise enough to be regarded as modern, the power
amp has a softness -- however enticing -- that might be too
romantic for those weaned on transistor equipment or current era
valve powerhouses like the big EAR, Audio Research or Beard
amplifiers. But I'll be damned if I'm going to apologize for the
Air Tight because I loved the lushness. It reminded me again and
again of a description John Atkinson gave me of the smaller Sonus
Faber speaker. 'Ken,' he said, 'it definitely has its flaws, but
it's just so damned musical.'

I couldn't agree more. Playing both modern, glassy recordings and
sonic masterpieces of the era of the Air Tight's inspiration, I
noted an unerring facility which these products have for
sweetening whatever sounds they are fed. Is it accurate? Hell,
no. But neither is it offensive in the way that identifiable
distortions or wild colorations are. The Air Tight amplifier
doesn't really add anything which would annoy; it merely shaves
off the edges which could become nasty. This was identifiable
whether I used the front sockets with a direct-injected line
level source or via the preamp through the rear sockets. Despite
my description of the ATM-1 as some kind of lavender scented
granny of an amp, it remained transparent and coherent enough to
reveal the benefits of the various bypass modes.

And then it hit me. Although I didn't have the gear to hand, I'm
absolutely certain that if these items were used with the kind of
audiophile which is so cherished in Japan, the sweetness would
offset the sharpness which I attribute to Decca cartridges and
horn-type loudspeakers. In which case the synergy of these modern
antiques with genuine antiques would provide some kind of
anachrophilic bliss.

As the ATM-1 can be modified for monophonic 80W, 2 ohm operation,
the power shortage is not a problem. (Indeed, the company already
manufactures a beast called the ATM-2 which uses four KT88s for
80W/channel from one chassis.) But #2059 is a fair chunk of cash
for what is the audio equivalent of a rebuilt-from-the-ground-up
Jag Mk II. The preamp, at #1769, has to compete with the
better-equipped, far more precise Audio Research SP-9 among
others. But that's missing the point. With that attitude, there'd
be no more Leica rangefinder cameras, only Canon EOS
auto-everythings. There'd be no more mechanical Rolexes, only
throwaway swatches. No, ownership of the Air Tights requires a
bit more than money. It requires a weird and wonderful blend of
nostalgia, an appreciation for hand-crafted mavericks, a sense of
aesthetics which deems a Bristol more righteous than a Porsche,
taste buds which prefer Nova Scotia salmon to that stuff from
Scotland. The Air Tights are to me simply the nicest products
around for powering classy little boxes like the Sonus Fabers,
for satisfying a craving for the past without the risk of running
elderly components. The ATC-1 and ATM-1 aren't really hi-fi
products after all. They're the stuff which are made of dreams.

Keywords

Air Tight, Audiophile preamp reviews, audiophile amp reviews, Air Tight Tube Audio Reviews

Subscribe to the Newsletter
Subscribe to HomeTheaterReview.com's Weekly Newsletter to get the latest news, reviews and insight on the world of home theater, HDTV and audiophile equipment. Subscription is 100% FREE!
*Required
Email Marketing by VerticalResponse
subscribe to rss Subscribe with RSS
Follow home theater equipment reviews and daily news via our RSS feed.
Related Stereo Preamplifier Reviews (Classic):
  • Comment on this article

    0
Post a Comment

Please answer the following question (required) before posting to help us prevent Spam.


enter to win

Today's Top Story

California Passes Anti-Flat-HDTV Legislation To Try To Save Energy

California Passes Anti-Flat-HDTV Legislation To Try To Save Energy -

As a resident of California who owns a "green home" complete with new windows, high efficiency air conditioners, space-age insulation and drought tolerant planting on over two acres of hillside - today's decision to toughen standards on HDTVs is a... Click for more...

Latest Stereo Preamplifier Reviews (Classic)

Quad II Reissue Preamp Reviewed -

A feature worthy of our 40th Anniversary issue. A once-in-a-career opportunity. That's what Editor Harris wanted for this issue, something so memorable that it would mark the occasion in style. Something to have every other magazine editor on the planet... Click for more...

Unison Research Mystery One Preamp Reviewed -

It probably took a bit longer to grow the wood which forms the Mystery One's case. All I know is that nearly a year has passed since I first took delivery of the prototype, and enough detail changes occurred between... Click for more...

Marantz Model 7 Reviewed -

Twist my arm. Go on. me to review a couple of products I've been dreaming about owning for years. What's that? If I've actually been waiting for 'years', did I suddenly find some mint originals? Not quite: Marantz took it... Click for more...

Krell KAV-250a and KAV-250p Reviewed -

What signals are you receiving from Krell? What do you make of the turnaround that has produced so much prime entry-level gear? Let's not be too glib about this, for even the Krell components we're about to explore sell for... Click for more...

Beard BB 30-60 Integrated Amp Reviewed -

Ever less than aggressive, Bill Beard has been quietly - if you'll forgive the term - manufacturing all-tube amplifiers for export these past few years. Those of us who see on occasion magazines from foreign countries have noticed ads for... Click for more...

Audio Research LS25 Preamp Reviewed -

Down-scaling - as opposed to dumbing down - has a patchy record in the annals of luxury goods. The VW/Porsche 914 didn't satisfy 911 wannabees, few would-be Leica M-Series owners cherished the economical CL and you'd have to hypnotise... Click for more...

Musical Fidelity Nu-Vista Preamp Reviewed -

Anthony Michaelson knows how to push the right buttons. All he had to say was the word 'nuvistor', and every tube crazy worth his weight in anode plates was clamouring for a listen. After all, wasn't the nuvistor the last-ever,... Click for more...

Marantz PM-17 Preamp Reviewed -

Having established itself as THE brand for affordable audiophile CD players, Marantz is going out of its way to prevent what's known as 'cherry-picking'. Cherry-picking happens when a brand has one outrageously successful product, but the rest of the range... Click for more...

Audio Research LS8 Preamp Reviewed -

All-tubed, classically ARC-styled and featuring a few touches which have filtered down from the dearer models, the LS8 joins the (thankfully) ever-lengthening list of entry-level high-end goodies...just in case you were afraid the Ref 1 pre-amp and Ref 600 monoblocks... Click for more...

Graaf 13.5B II Preamp Review -

Eagle-eyed readers blessed with -grade memories know that I've used GRAAF's flagship pre-amp off and on since reviewing it five years ago. The sonic performance of the GM13.5B made it one of my references for a tube pre-amp with balanced... Click for more...

Latest Stereo Preamplifier Reviews (Classic)

Quad II Reissue Preamp Reviewed -

A feature worthy of our 40th Anniversary issue. A once-in-a-career opportunity. That's what Editor Harris wanted for this issue, something so memorable that it would mark the occasion in style. Something to have every other magazine editor on the planet... Click for more...

Unison Research Mystery One Preamp Reviewed -

It probably took a bit longer to grow the wood which forms the Mystery One's case. All I know is that nearly a year has passed since I first took delivery of the prototype, and enough detail changes occurred between... Click for more...

Marantz Model 7 Reviewed -

Twist my arm. Go on. me to review a couple of products I've been dreaming about owning for years. What's that? If I've actually been waiting for 'years', did I suddenly find some mint originals? Not quite: Marantz took it... Click for more...

Krell KAV-250a and KAV-250p Reviewed -

What signals are you receiving from Krell? What do you make of the turnaround that has produced so much prime entry-level gear? Let's not be too glib about this, for even the Krell components we're about to explore sell for... Click for more...

Beard BB 30-60 Integrated Amp Reviewed -

Ever less than aggressive, Bill Beard has been quietly - if you'll forgive the term - manufacturing all-tube amplifiers for export these past few years. Those of us who see on occasion magazines from foreign countries have noticed ads for... Click for more...

Audio Research LS25 Preamp Reviewed -

Down-scaling - as opposed to dumbing down - has a patchy record in the annals of luxury goods. The VW/Porsche 914 didn't satisfy 911 wannabees, few would-be Leica M-Series owners cherished the economical CL and you'd have to hypnotise... Click for more...

Musical Fidelity Nu-Vista Preamp Reviewed -

Anthony Michaelson knows how to push the right buttons. All he had to say was the word 'nuvistor', and every tube crazy worth his weight in anode plates was clamouring for a listen. After all, wasn't the nuvistor the last-ever,... Click for more...

Marantz PM-17 Preamp Reviewed -

Having established itself as THE brand for affordable audiophile CD players, Marantz is going out of its way to prevent what's known as 'cherry-picking'. Cherry-picking happens when a brand has one outrageously successful product, but the rest of the range... Click for more...

Audio Research LS8 Preamp Reviewed -

All-tubed, classically ARC-styled and featuring a few touches which have filtered down from the dearer models, the LS8 joins the (thankfully) ever-lengthening list of entry-level high-end goodies...just in case you were afraid the Ref 1 pre-amp and Ref 600 monoblocks... Click for more...

Graaf 13.5B II Preamp Review -

Eagle-eyed readers blessed with -grade memories know that I've used GRAAF's flagship pre-amp off and on since reviewing it five years ago. The sonic performance of the GM13.5B made it one of my references for a tube pre-amp with balanced... Click for more...

All Stereo Preamplifier Reviews (Classic)

Latest Equipment Reviews

Rotel RA-1520 Integrated Amplifier Reviewed -

Rotel has been creating audio components for more than 46 years that have all been designed with the goal of bringing high-end audio technology to the more discriminating audiophile. Rotel's RA-1520 integrated amplifier retains the same focus, as this amplifier... Click for more...

Parasound 5250 Five Channel Power Amplifier Reviewed -

As an audio manufacturer that is very proud of its ability to design high-end audio components for the very discerning ears of Hollywood's engineers, Parasound is also insuring that their power amplifiers for the consumer market are second-to-none. The 5250... Click for more...

Vizio VSB210WS Sound Bar with Wireless Subwoofer Reviewed -

Sound bars have always been a bit of the redheaded stepchild of the home theater world for me, a replica of sorts for those unable to accommodate or afford a proper home theater. Of course I jumped to this conclusion... Click for more...

Definitive Technology Mythos 7 On-Wall Speaker Reviewed -

When it comes to perfect replication of professional theater sound, the most important component of any home theater's speaker configuration is the center channel speaker. This speaker not only has to deliver a movie's dialogue with crystal-clear audio imaging, it... Click for more...

Benchmark DAC 1 HDR Reviewed -

While analog reproduction of audio is all the rage these days, most, if not all of us have our music in some digital form. Be it on a hard drive, iPod, Compact Disc or server, we all need high quality... Click for more...

Definitive Technology UIW 75 In-Wall Speaker Reviewed -

One of the primary functions of a first-rate in-wall speaker is its ability to disperse superb high-end audio to every part of the room, no matter where the speaker itself is placed. The design team at Definitive Technology knows just... Click for more...

Outlaw Audio ECS-10 Subwoofer Reviewed -

A major problem in the past with small and compact subwoofers was their inability to deliver strong and deep low-end to the average soundstage. Outlaw Audio's design team was well aware of this challenge when they started developing the ECS-10... Click for more...

Toshiba REGZA 46SV670U LED LCD HDTV Reviewed -

LED backlighting is the way of the future for LCD televisions. Most of the top-selling LCD manufacturers now offer at least one line that uses LED backlighting. Some of these models only place the LEDs around the edges of the... Click for more...

Energy ESW-V10 Subwoofer Reviewed -

Energy is an audio manufacturer that is fairly well known for developing quality speakers at a mid-range price and now they are slowly getting into producing a more high-end subwoofer product line starting with the ESW-V10. The list price for... Click for more...

JVC LT-42X899 42-Inch LCD HDTV Reviewed -

If you have been looking for an HDTV that eliminates pesky motion blur while viewing action-packed Blu-ray discs, you should be very interested in what JVC is calling their "Clear Motion Drive III" technology. That technology is integrated into their... Click for more...

Read All Reviews