The two-channel Tube-Tech LCA-2B offers all-tube compression with the added flexibility an independent compressor and limiter per channel. It's perfect for drum overheads, stereo room mics, stereo guitar, bus compression, and just about any other stereo source you have in mind. You also have the option of inputting two mono sources, compressing on one while limiting on the other.

Tube-Tech LCA 2B Compressor/Limiter, First Take:

All tube, 2-channel with independent compressor and limiter per channel
6 attack/release presets and manual control
Multi-unit link mode

Independent Compressor/Limiter

The rackmount Tube-Tech LCA 2B is a two-channel unit with an independent compressor and limiter per channel. The unit is all-tube based (except for the power supply and sidechain circuit). Output gain control is placed between the VCA and output stage. The VCA (1 dual triode) is placed between the input transformer and the output stage (2 dual triodes). The audio signal is picked up after the VCA and fed to the sidechain circuit.

Six Presets and Manual Control

The stereo compressor has six attack/release presets as well as manual control. The limiter attack/release is fixed and equipped with an on/off switch. The LED display is fed from the control amp. The limiter LED is fed from the limiter buffer. The audio path is fully symmetrical from input to output. Input and output have fully floating transformers. All DC voltages are stabilized, except the anode voltage for the output stage, which is only filtered.

Link Mode

The control signal from the compressor and limiter is combined and sent to the link switch and to the control amp, which feeds the VCA. The bi-directional link busses are accessible at two 1/4" stereo jack sockets on the rear panel. The channels can be linked together for stereo applications and also linked to other LCA 2B's via the two link busses and a standard stereo jack/jack cord. A switch (Link 1, Link 2) on the front panel selects which compressors are interconnected, and on which bus they are connected. If you select Link 1 on both channels, they will perform the same gain reduction. With several LCA 2B compressors in a rack, you can select which ones will work together. For example, by selecting LCA 2B #1, Ch. 1 on link 1; LCA 2B #2, Ch. 2 on link 1, and LCA 2B #3, Ch. 1 on link 1, they are now interconnected and will all act with the same compression. By interconnecting them in this fashion the unit that performs the most compression controls the others. It is also possible to have all the interconnected compressors control each other simultaneously.

About Tube-Tech

For over twenty years, Tube Tech has been one of the most prominent names in all-tube signal processing equipment. You'll find their gear in the best recording and mastering studios around the world. The company's founder, John Petersen is an electrical engineer who was factory trained at Solid State Logic, EMT, Studer, Sony, Neumann, and NTP Electonik (digital audio routers). He also designed tape recorder playback/recording amps for Lyrec tape recorders (found in the studios of the legendary Joe Meek and Vangelis). His first design under the name of Tube-Tech was an all-tube equalizer based on the legendary Pultec EQP 1A. Petersen continued to design and manufacture a number of innovative all-tube outboard processors including preamps, multiband compressors and summing amps. Thanks to John's dedication to high-quality analog sound you'll see Tube-Tech gear in the racks of pro audio legends such as multi Grammy Award winner Al Schmitt, (Frank Sinatra, Steely Dan, Toto, Quincy Jones, Natalie Cole, Diana Krall), Grammy winner Joe Chiccarelli, (Elton John, Beck, U2, Tori Amos, Counting Crows, Offspring), engineer Russ Long (Sixpence None The Richer, Wilco, Dolly Parton, Allison Moorer), producer-engineer Tony Shepperd (Elton John, Madonna, Kenny Loggins, Barbra Streisand, Lionel Richie, and Whitney Houston), and many more.

  • Separate compressor and limiter
  • Frequency response @ -3 dB: 5 Hz to 50 Khz
  • Low noise: < -85 dBU @ 10 dB gain
    Output gain control
  • Clickless bypass relay
  • LED display for gain reduction
  • Variable ratio from 1,6:1 to 20:1
  • Variable threshold: off to 10 dBu
  • Selection between six presets and manual controlled att/rel
  • Variable threshold: off to 0 dBu
  • On/off switch
  • LED indication
  • Gain: -6dB-+10dB
  • Input impedance: > 2 k_
  • Output impedance: < 60
    Distortion (THD+n @ 40Hz): 0dBU < 0.15 % ; 10dBU < 0.15 %; max output (1% THD+n) > +26dBU
  • Noise (Rg=200_): Gain 0dB-10dB; 22Hz-22kHz; < -85dBU < -80dBU; CCIR-468-3: < -75dBU < -70dBU
    Frequency response (-3dB): 5Hz-50kHz
  • Crosstalk (20Hz-22kHz): < -70dB
    CMRR (@ 10kHz): < -60dB
    Tracking (0 to -20dB gain reduction): ±1dB
  • LED display for gain reduction: 0dB to 20dB
  • Compressor:
    • Ratio: 1,6:1 to 20:1
    • Threshold: off to -10dBU
    • Attack (manual): 0,2 to 70 mS
    • Release (manual): 0,1 to 2 S
    • Preset attack/release:
    • attack release
    • pos 1. 1,5 mS 0,25 S
    • pos 2. 1,5 mS 0,8 S
    • pos 3. 3 mS 2,2 S
    • pos 4. 6 mS 5,0 S
    • pos 5. 3 mS 0,5/4 S
    • pos 6. 1,5 mS 0,5/4/20 S
    • The release time in position 5 and 6 is program dependent, that is:
    • pos 5, 6 for short peaks: 0,5 S
    • pos 5, 6 for long peaks: 4 S
    • pos 6 for continuously high levels: 20 S
    • Threshold: off to 0dBU
    • attack: 0,6 mS
    • release: 0,5 S
    • ratio: 20:1
    • LED indicating limiting
    • Tubes: 2xECC81, 2xECC82, 2xECC83
    • Dimensions: H: 2 units, W: 19", D: 205mm
    • Weight: 6.5kg
    • Power requirements: (115V/230 V, 50-60Hz): 30-45W

    Featured Articles