Greetings from Berlin,
as we had some Information regarding the Air Tight ATM2, I want to show 3 different Air Tight amp systems with some explanation and pictures, also trying to give some info on NOS Tubes.
So - here we go....
Basic stuff:
The company´s name is A&M LTD - Air Tight is the brand name.
A&M LTD has also a second brand - acoustic masterpiece, which is moderate priced and not made in Japan in the Air Tight factory.
Th founder of Air Tight is Miura San, who worked more than 30 years for Luxman and designed most of their legendary tube amps.
The company is really small, Miura and his partner, and 6 other people are working there.
Everything is handmade.
All Air Tight components have some things in common:
1. All chassis are made of steel - not aluminium.
This philosophy shares Air Tight with Shindo and also Kondo.
The reason for using steel is, that those companies do not use screened cables throughout their topology, to get proper shielding, the amplifiers has to be build in a certain style, were every section has his own compartment.
If you ever see a Shindo, Kondo or Air Tight open, you see the amazing amount of metal work.
The stele is also not screwed together, it is made of one pice, only the top plate and the bottom plate is screwed on.
Most of the bottom plates (every power amp...) are made of copper!
And some of the internal parts, which needs extra shielding and decoupling are also made out of copper - this technique shars Air Tight with Kondo.
The whole chassis is made in a style, that it is not recommended to use moern rack systems, as Finite Elements or HRX base systems.
It is ment to be put on simple plywood - this is exactly the same philosophy Shindo San employed in his amplifiers.
With air tight you should use a Box Furniture system or Norbert Gütte´s Bench.
The amplifiers bring everything, which is needed to decouple them from the platform, were they stand - if you do not follow that rule, they will sound slow, muddy and lifeless....
Air Tight has a tremendous lineup, which is addressing the vinyl fan....
It is also a little bit as with Shindo, because Miura builds Push Pull and SET amps - so there is a different philosophy as with Kondo San.
Also Miura do not use silver in his designs - it is always and throughout copper.
As everyone knows, the miracle of a tube amp is the output transformer together with the design, Miura is using just the finest transformrs, which are available today.
His output transformers are coming from Tamura ans Hashimoto, his Step Up transformer capsules are sourced from Hashimoto and My Sonic Lab (Matsudaira San of My Sonic Lab is a longtime friend of Miura and designed Air Tight´s cartridges).
All amps fature just single ended connection, and are built in a very, very classic way - so no modern features as volume control, and other gimmicks....
All gear is point to pont wired - so no printed circuit boards.
Miura is not using, as Shindo is doing, NOS parts - all parts are modern - and of the highest quality.
He also collects parts for further use, if he found things he really likes a lot.
Every preamp is made in two different versions, HQ and non HQ.
Th HQ version, has higher quality parts inside and the legendary Alps RK 501 volume potentiometer - the same Kondo uses in his M1000 and M77.
It is the best volume pot money can buy and nearly as good as volume switches, which are not as fine in their volume steps (no steps with the pot of course).
All amplifiers and preamps are very classic in their outer and technical design.
A lot of his creations will remind us at Marantz and vintage Mcintosh.
But it is not copied, Miura puts a lot of his own ideas into his products and his main goal is simplification and purification, if Miura can spare a stage - he would do that.
He can afford that, because he designs a tremendous quality in his power supplies.
Every tube has it´s own heater rail, and in this style he continues using highest quality techniques.
The portfolio is today something very special - you can choose of:
Power amplifiers
ATM1S EL 34 Stereo Amp, configureable to triode mode
ATM2 KT88 Stereo Amp, configureable to triode mode
ATM3 EL 34 Mono Block - switchable to triode mode
ATM4 6L6 GC or 5881 Stereo Amp - As mono block switchable
ATM300b 300B SET Stereo Amp
ATM211 211Mono Block Amp
Reference Amps - Mono and stereo Amps using al lot of 6550 - high wattage amps - which I think are not so interesting......;-))))
ATC1 (HQ) Based in some design aspects on the Marantz 7C, full function pre with MM RIAA stage and, very interesting, a RIAA output.
The output stage is designed as a kathode follower design
ATC2 (HQ) Reference Line Stage, could be made to a full function pre with the ATE1 RIAA, which gets his power from the power supply of the ATC2.
The output stage is a SRPP configuration.
ATC3 (HQ) Line Stage - shares the same basic deign as the ATC2 but with diode rectification instead of tube rectification.
ATE 2001 Ultra Reference full function pre, has a complete tube power supply in a separate compartment, and 2 Line inputs the rest is dedicates to phono, only Air Tight preamp with built in SUT´s, which is deigned by My Sonic Lab.
ATE2 The smaller version of the ATE 2001, which has not a separated power supply and only one line input - the rest is also dedicated to Phono....
ATE 2005 Stand alone phono stage which shares the same topology as the ATE2 - but without the tube power supply - it is the only Air Tight RIAA stage with a real active MC input, which uses Class A puristic transistor head amp on top of the tubed MM stage
ATH2A - Step up transformer using Hashimoto HSX capsules
ATH2A Ref. - Step Up unsing My Sonic Lab SUT technology
Carts:
Air Tight PC1 Supreme and PC1 Supreme Mono
Air Tight PC1 and PC1 Mono
Air Tight PC7 (brad new)
Speakers:
Air Tight Bonsai mini monitor systems with a single chassis driver
That is the lineup....tried to give some explanations.
As you may recognize, you can chose a lot of different power tube flavors, KT88, EL 34, 6L6/5881, 300B, 211.
And also you have 2 of the 3 techniques to get low output impedance at the output auf the preamps - kathode follower, and SRPP, what is missing is a preamp with output transformer technology.
Let´s come to my setup.
I have three different amplifier/preamplifier settings in two different rooms.
One setting is dedicated to the legendary LS3 /5a speakers - I adore them...
The other setting works with Quad ESL 57 Manfred Stein.
Here we go - some pics and some additional explanations regarding NOS tubes...
This is room one with the LS3/5a installation, you can see Air Tight ATM2, ATC1 HQ and ATH2A Step Up transformer, a highly modified Marantz CD94 with passive IV stage and Siemens Klangfilm output transformer, and a Bauer DPS III IT with Frank Schröder tonearm.
A close up of the ATM2 - fully loaded with fine NOS tubes, GEC KT88 Black Plates Triple Getter (the king of all KT88 - you cannot substitue those with new designs), Telefunken ECC83 and ECC82 Smooth Plates ans RCA 12BH7 Black Plates.
The output trannies are huge Tamura.
This is the ATM1S, an EL 34 design, here wired in triode mode and fitted with Telefunken Single Slot Plates,Double O Getter, RCA/Honeywell 12AU7 Clear Top and RCA/JRC 12AX7 Black Plates.
It is one of the very best EL 34 amplifier designs in HiFi history, the ATM1S uses Hashimoto output transformers
Bias Meter of the ATM1S - it is the attention to detail, which makes sometimes the difference....
As Miura sell the amplifiers worldwide, he stopped using NOS tubes in that time, Europe developed the stupid ROHS law - it is now forbidden to sell gear in Europe which uses parts not ROHS conform.
Since that day we users have to get the NOS stuff ourself.
If you listening to any Air Tight in a shop - you will listen to EH russia tubs, which gives you just a hint, of what will be possible, if you switch to high quality NOS glass.....
Internal view of the ATC1 HQ full function preamplifier.
You see the classic design of all the different compartments, the ATC1 HQ has 7 compartments and is using also copper to shield the different sections from each other.
The compartments are:
1. power supply
2. poti and switches
3. line stage circuit
4. line stage tubes
5. RIAA stage circuit
6. RIAA stage tubes
7. Input and output connections
Air Tight ATM4 6L6 GC design, it is possible, if you buy two of them, to switch them to mono operation.
A true classic
Internal view of the ATM4, I use here General Electric 6L6 GC Double D Side Getter Grey Plates, RCA 6CG7 Clear Top, Telefunken ECC801S
This is the ATC2 HQ line stage - I use it together with the ATM4.
The ATC2 is a tube rectified line amplifier with a tremendous flexibility, it has 2 Tape connections packed with copy and listen functions, 4 additional line inputs, 2 line outputs and uses 1X 6X4 Rectifier - here I use a GEC CV 4005 Black Plates, 2X ECC82, which are here Amperex Bugle Boy 12AU7 Large Plates D/Foil Getter, and a 12AX7 - also an Amperex large D/Foil Getter tube.
Complete system with a vintage Accuphase tuner
Here we see the stand alone RIAA stage, the ATE 2005 with an internal view.
It is packed with the finest parts and also made designed with different compartments.
The complete RIAA section is mounted an a copper plate.
It is fitted with 3X Siemens Halske ECC83 Long Plates Double Getter Support MC1 tubes - very nice...
A closer look the holy GEC KT88 Black Plates of the ATM2
The ALPS RK 501 volume pot of the ATC1 HQ
ATM1S equipped here with Valvo labeled Mullard XF2 Double O Getter EL 34
Here the same tube, but with the original Mullard logo....
I hope I managed to get some of the informations about Air Tight to you guys .
Enjoy the pictures, they tell more than all my words.
Greetings from Berlin
Ekki
PS: More will follow.....;-)))))