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Analogue Tube AT-1 Fairchild 660 Mono Compressor Limiter

£10,164.00 inc. vat
£8,470.00 ex. vat
Please contact us for availability.

Analogue Tube AT-1

The Analogue Tube AT-1 is a mono limiter closely based on the classic Fairchild 660 using all the original parts specified in original models of the day. The circuits for these units are the same as the 660 models which include the use of the 6386 tubes.

The Fairchild 660 is not one half of the stereo 670 version as it behaves slightly differently in operation to its stereo counter-part. These models have a different tube power supply and different tubes for the AC threshold, as well as transformers. Standard additions to this limiter include; Bypass, External *Key* input and a 211%/div stepped AC threshold as an option. Stereo linking is standard.

The AT-1 is a Mono compressor with a stepped and tapered audio attenuator. It provides the user with more gain than the AT-101 and a rich tone. It has bypass, a key input stage, stepped AC threshold and stereo linking ability. All inputs and outputs are transformer balanced. Both AC threshold and gain reduction circuits can be split allowing the user to pass audio only through the tube input stage. The TC settings are the same as the stereo units with the same micro second attack times.


  • Original tapered 1db per step ‘T’ Attenuators (21 step total)
  • Original complement of tubes
  • Fully transformer balanced audio path
  • Newly developed 6386 Triode tubes– new feature
  • 5 &12 Watt Non-Inductive Wire-Wound resistors throughout Audio Path
  • Original Non-Inductive Pots throughout
  • 21 stepped AC threshold 1% tol pots fitted
  • Switched bypass control
  • Switched *key* input
  • Switched Stereo linking
  • Original Anode supply
  • Original CVT heater supply
  • Hovland Musicap Polypropylene film capacitors throughout
  • Silver Mica capacitors
  • PTFE ‘Point to Point’ wiring throughout
  • Ceramic Tube sockets throughout
  • Stereo Link switch fitted
  • Simpson Electric metering
  • Top panel torque hinges
  • Original front panel
  • New Chassis Design
  • Large Knobs
  • XLR Chassis mounting connectors
  • Specially made Sowter audio transformers throughout
  • Switched IEC mains socket
  • US & EUK adjustable