Compressors / Limiters

Simple:Hit your choice of buttons and twist the threshold for radio-ready results Smart Dyn Dual Slope Detection: Automatically limits peaks while stealthily compressing the average.Auto Attack/Release: Replace "guess" with "yes" for rapid-fire results. Transparent:Performs like an automated fader: No more drawing vocal rides.True Stereo Dual Detector: Traditional linking shares one detector, often resulting in a narrower stereo image.Immaculate VCA: Virtually no distortion, even with 20dB of gain reduction. Powerful:Internal sidechain circuitry houses the audiophile soul of the compressor:Bass Cut: Tightens the track without sacrificing the low end.Sibilance Boost: Shave sibilance and shrill histrionics with zero post-compression hangover.

Discrete Compressor, Re-Issue. Originally released in the 70's, the API 525 is a "feedback" type compressor, such as the 1176 and 660, etc. An input (threshold) control and output (make-up gain) control are provided. An additional "Ceiling" fine tune function modifies threshold and make-up gain for precise changes in compression without changes in output. A compression/limit switch sets ratio at either 2:1 or 20:1. Attack time is as fast as 15u/s. Four auto release modes are offered via two switches, 0.1s, 0.5s, 1.5s, & 2.0s. A De-Ess function inserts an inverse vocal energy curve filter in the detector for effective sibilance/p-pop reduction. The 525 is an identical re-issue of one of the most popular API products ever.The API 525 is perhaps the most successful solid state feedback compressor in history. It delivers dynamics control behavior unlike VCA "feed forward" compressors so common today. A remarkable multi-function "ceiling" control can increase gain reduction (lower threshold) while simultaneously raising output level to match, so the user can alter dynamics "on the fly" without level changes. This re-issue design has been taken from the original blue prints and spec control drawings from the API archives.        FEATURESAudio circuit uses the 2510 and 2520 Discrete Op Amps with transformer outputContinuously variable detented Threshold controlContinuously variable detented Attack and Release controlsContinuously variable detented Ratio controlOutput Fader level control10 segment VU/Gain Reduction meter with selector switchOverload LED"Link" switch for multiple unit interdependent compression linking"New"/"Old" switch for feed-forward or feed-back compression"Hard"/"Soft" compression curve knee switchPatented "Thrust" switch for frequency dependent side chain control"IN" switch with hard relay bypass when in the "Out" position

The MANLEY VARIABLE MU® LIMITER COMPRESSOR has been our best selling product for many years. It is one of the very few compressors that has become a real standard in Mastering studios and contributed to most hit records over the last decade and probably the next. "Mu" is tube-speak for gain, and Variable Mu® is our registered trademark for this limiter compressor. It works by using the "remote cut-off" or re-biasing of a vacuum tube to achieve compression. The precious vintage Fairchild 670 also uses this technique and is one of few all-tube compressor to do so, that we know of. Even the side-chain has glowing rectifier bottles. How’s it work? The unique 5670 dual triode is at the center of the peak-reducing and compression action constantly being re-biased by the vacuum tube rectified side-chain control voltages which cause this tube to smoothly change its gain. Just like that.The COMPRESS mode is soft-knee 1.5 to 1 ratio while the sharper knee LIMIT mode starts at 4 to 1 and moves to a more dramatic ratio of 20 to 1 when limiting over 12dB. Interestingly, the knee actually softens as more limiting is used. Distortion can be creatively used by turning up the Input and turning down the Output while using very little or no compression. See the gain reduction curves here!You might notice that the Variable Mu® Limiter Compressor has a ganged input control, but do not jump to conclusions that it is mono-unfriendly. Track away! There are separate threshold and output controls to make compensations with plus you can always adjust your individual source levels elsewhere, right? The advantage of the stereo input control becomes dramatically clear when you switch to LINK mode, and that’s what our Variable Mu® Limiter Compressor does better than anything else: final mix, 2-track, or mastering limiting and compression. Like one reviewer put it: “It’s like pouring a bowl of sweet cream over the mix.” Mmmmmm. Yummy. Give your music a big hug.Specifications:MANLEY input & output transformers with nickel laminations in mu-metal cases with flat frequency response from 20Hz-25KHzBALANCED INPUTS & OUTPUTS (600 Ohms)Fully differential ALL-TUBE circuitry using one each 5670, 5751, 7044 or 5687, & 12AL5 per channelIndependently regulated B+ and Heater suppliesHard-wire BYPASS switchStepped switch INPUT attenuator as of 10/2011. (older units use Silent dual-ganged potentiometer)RECOVERY 5 steps: 0.2s, 0.4s, 0.6s, 4sec., 8sec.Variable ATTACK: 25msec-70msecContinuously variable THRESHOLDLIMIT (4:1 to 20:1) or COMPRESS (1.5 to 1)HP SC: High Pass Side Chain Filter -3dB @ 100HzLarge ILLUMINATED Sifam METERS (older units before serial number MSLC61642 shipped before 12/2003 use: 26V 1.2W FESTOON LAMPS; Manley's Part Number: VAR016B) Order spare bulbs using our parts order form. (newest units after serial number MSLC61642 shipped after 12/2003 use white LED lighting)STEREO LINK SWITCHSeveral units can be linked for Surround (custom order )Maximum gain: 35dBMax. output: +30dBu (26Vrms) 26dB Headroom

FALCON is a classic sounding tube compressor in a 500 series package. FALCON features 3 attack and 3 release time settings, hard and soft knee choices for compression or limiting, two different audio path sounds, wet-dry mixing for parallel compression, and is linkable.The audio path color is changed by modifying the tube circuit so it has negative feedback or does not have negative feedback.  This along with the optical like quality of the compressor allows for a colored vintage sound or a much cleaner sound with optical characteristics. When linked the master unit controls all functions on the slave except for wet-dry and make up gain.  The link system is capable of doing 5.1.

SLAM! stands for "Stereo Limiter And Micpre" and it pretty much describes what it will do to most VU meters. We had to put a switch on this limiter to drop its internal VU meters down 3 & 6dB to keep the poor little needles from bending– it'll get LOUD fast (hence the exclamation mark). And on top of being an amazing pair of (actually four) Limiters, and Class A tube mic preamps, it also has masters degrees in DI, AtoD and DtoA, VU and PPM but that was too much for an acronym.When it comes to classic gear, especially classic limiters, we can all agree numbers like LA2s, 1176s, 2264s, and others come to mind. What if all those sounds were to be found in one stereo tube unit. Interested? We combined our favorite Electro-Optical circuit (ELOP®) with a damn fast FET based brick-wall limiter reminiscent of some cool classics. And we added a sidechain filter that can remove low frequencies that makes it more useful for a variety of tasks, while retaining that easy, "it just works" quality that has made it a favorite for vocals everywhere. The FET-based limiter has different desirable characteristics that both optimise the signal for digital recording, due to the brick-wall capability, and let you dial in how clean or crunchy, or punchy, and how loud and proud you want it. Manley is excited to announce the SLAM! Specifications:Input Tubes: 2 x 12AT7A NOS GE specially selected by Manley Labs for lo-noise and stable biasOutput Tubes: 2 x 6414W NOS USA dual triodesI/O: MANLEY transformer coupled Balanced Inputs and OutputsMicpre: Selectable 48V phantom power and PHASE REVERSEGain: 60dB max Micpre, 43dB max DI, 20dB max Limiter GainInput Impedance: 2000Ω Micpre, 1MegΩ DIFET Limiter: Attack: approx. 100μS; Release: 10mS to 2Sec; Ratio: better than 20:1ELOP Limiter: Attack: approx. 10mS for 6dB GR; Release: 2.5 Sec; Ratio: 10:1Frequency Response: 5Hz to 60KHzMaximum Output: +32dBm, +30dBm (into 1KΩ load)THD+N:

High-end dual mono tube compressor, Optical gain reduction element, Linkable for stereo applications, Dual VU-meters showing output or compression, Variable attack and release with a 1,5:1 to 10:1, Output Gain (off to +10 dB), Frequency response @ -3 dB: 5 Hz to 60 kHz, Low noise: < -80 dBu @10 dB gain, Conductive plastic potentiometers, Gold plated switches, Clickless bypass relay, XLR I/O, 19"/2HE.

Stereo compressor/gate with integrated PSU, Over Easy function (automatic attack and release), Compressor-Ratio "1:1 - 4:1", XLR ins/outs, -10/+4dB switchable, stereo link, 19", 1U

The Distressor is an automatic gain (or volume) control device (AGC in engineering terms) designed for pro audio (music) applications. Basically, it electronically controls the volume of just about any source in a very pleasing, and "musical" manner - adding fullness, intelligibility, and especially in the Distressor's case - excitement. This type of device is often called a "limiter" or "compressor" by audio industry people. Its most probable uses will be in recording studios, live sound situations, movie sound production, and radio broadcast production.

Empirical Labs ELDS Derresser, Module for API-500 System, Freq. Response is 3 Hz to 120 kHz (-3dB points), Dynamic thomann Range - 115 dB from maximum output (.5%THD soft clipping) to minimum output. Transformerless noise floor typically – 93dBu, Distortion Ranges between .0035% and .01% depending on mode and settings, DC coupled Input and Outputs, High quality audio caps used internally, Input Balanced, thomann Output single ended but with balanced impedance, Pin 2 hot, Input Impedance is 20k Ohm. Output impedance is less than 51 ohms, D-S Dynamics Time Constants - Attack time is less than 1mS. Release .04 sec, fixed internally, Power Consumption – 8 thomann Watts max. 4 Watts Typical

The Retro Sta-Level is a replica of the legendary 1956 Gates Sta-Level. The Sta-Level dominated the sound of hit radio in the 1960's. Now these super musical sounding compressors have found their way into today's hits. The Retro Gold Edition celebrates fifty years of the products existence. The Sta-Level uses the coveted 6386 tube in a classic G.E. circuit design. Alternatively, the Gold Edition Sta-Level uses a pair of commonly available 6BJ6 tubes (stock). The customer has the choice to use their own 6386 they provide or the 6BJ6 provided with the purchase of the unit. The choice is yours and the sound is undeniably true to the original either way. Specifications Gain Reduction Threshold: Continuously adjustable from +24dBm to -20dBm Available Gain Reduction: 40dB Total System Gain: 35dB (with standard input and output pads) Distortion: 1 percent or less from 0-30 dB gain reduction Frequency Response: ± .25dB from 20-20,000 Hz Noise: -70dB or better referenced to gain reduction threshold Output Level: Continuously adjustable from -40 dBm to +18 dBm Input Impedance: Accepts low impedance active or transformer balanced 0-600 Ohms Output Impedance: 600 Ohm transformer balanced, terminated and resistive pad coupled Tube Complement: 2-6BJ6), 1-12AT7, 2-6V6GT, 1-6AL5, 1-OB2, 1-5Y3 Power Requirements: Three prong IEC - Switchable 115-230 VAC - 50/60 Hz Mounting Requirements: 3U metal rack 5.25" high, 19" wide, 8" deep

The Tube-Tech CL1B features a gain-reduction element, positioned immediately after the input transformer. It is controlled by the sidechain amplifier, which also contain the two time control circuits – one for fixed and one for variable Attack/Release. The two time-controllers can either be used separately or combined. This circuit contains semiconductor OP-amps for the entire control. The gain-reduction element is followed by a tube-based push-pull amplifier with variable gain up to 30 dB. A dedicated Bus selector with three positions (Off, Bus 1, Bus 2) is used whenever you want to link several compressors together. Input and output transformers have a static-screen between the primary and secondary wirings. Both Input and Output are balanced as well as fully floating.The CL 1B has proven its value by adding that sought-after vintage warmth and realism to the most demanding studio tracks.The Tube-Tech CL 1B main features include: Unique low distortion gain-reduction element All tube-based push-pull amplifier Multiple interconnection of several compressors via two busses VU-meter for monitoring input, compression and output Continuously variable attack and release time Gain Range (off to +30 dB) Variable Threshold (off to -40 dBu) Frequency response @ -3 dB: 5 Hz to 25 kHz Low noise: < -75 dBu @30 dB gain Clickless bypass switch

The Distressor is an automatic gain (or volume) control device (AGC in engineering terms) designed for pro audio (music) applications. Basically, it electronically controls the volume of just about any source in a very pleasing, and "musical" manner - adding fullness, intelligibility, and especially in the Distressor's case - excitement.This type of device is often called a "limiter" or "compressor" by audio industry people. Its most probable uses will be in recording studios, live sound situations, movie sound production, and radio broadcast production.

The EL7 FATSO is a modern digitally controlled analog device that offers many of the " musical non-linearities" exhibited by the older tube, class A discrete, and magnetic tape mediums. This two channel audio processor will musically integrate frequencies and transients and increase the apparant volume without actual increase in peak levels. In addition, two channels of famous Empirical Labs compression are provided. There are several compressor "types" with fixed attacks and releases (if you want a fully controllable compressor, you will need the Empirical Labs Distressor!).

TRAKKER is a high quality Single Channel Discrete Class A Compressor Limiter. It functions either as a musically transparent compressor or as a vintage compressor - limiter with selectable hard or soft knee.TRAKKER is a maximum-versatility toolkit for solving real-world recording, broadcast, and sound reinforcement problems with the utmost attention to signal quality. Trakker can create distinct new sounds or maximize existing ones. TRAKKER has adjustable threshold, attack, release, knee shape, and makeup gain controls. In addition to Character Switchthese controls, a function switch allows the selection of transparent operation or vintage operations such as optical, air optical, soft knee, and hard knee - each with four different amplifier/gain control sounds.Amplifier gain control sounds are: Transparent Vintage (tube or old style Class A) Transparent with VCA artifacts Vintage with VCA artifacts

The Cranesong STC-8 Stereo Mix Buss Compressor/limiter. Highly regarded and sought after processor capable of emulating vintage equipment and creating distinctive new sounds to enrich lifeless audio and digital recordings. The Cranesong STC-8 Stereo Mix Buss Compressor/limiter is a high quality stereo compressor combined with a remarkably dependable peak limiter, providing overload protection critical to digital recording and broadcast transmitters. The STC-8's compressor is engineered to provide musically transparent gain control, but is also capable of emulating vintage equipment and creating distinctive new sounds. In addition, a switchable enhancement circuit creates analog and tube like warmth to enrich lifeless audio and digital recordings. This vast flexibility is simplified by the inclusion of several optimized presets, allowing fast, easy set-up on a wide variety of sounds. It can operate in true stereo or discrete independent mono, accessible by a front panel switch. The STC-8's sophisticated side-chain allows both compression and peak limiting to take place simultaneously, using the same proprietary gain circuit. High signal quality is maintained by utilizing a discrete class A audio path, and by eliminating any VCA or optical gain control elements.  The STC-8 requires 2 rack spaces. All inputs and outputs are transformerless and balanced. The toroidal power transformer is UL approved and allows four line voltages for international use. The STC-8 delivers consistent gain control without sacrificing musical definition or harmonic richness.          FEATURES Highly regarded and sought after processor capable of emulating vintage equipment and creating distinctive new sounds to enrich lifeless audio and digital recordings Simultaneous Compression/Limiting Discrete Class A audio path Balanced/ Transformerless I/O Quick & Easy Presets Transparent Overload Protection Stunning versatility to produce clean or charactered, well glued mixes Transparent sound, highly regarded for use on vocals, overheads, toms and acoustic guitar as well as the mix buss

Thermionic Culture have released a new version of the Mastering valve compressor, the Mastering Plus. The classic hand built point to point wired soft knee compressor has a compression ratio from 1.2:1 to 5:1 at 15dB of compression and uses Mullard and Siemens valves and custom Sowter transformers.Following on from the success of the previous models including the red face anniversary limited edition the new model features new switched and stepped rotary controls for quick and easy recall. The input gain features a 24 position ELMA, a 11 position ELMA for the Threshold, 6 position ALPHA attack and release and a 31 position OMEG stepped output pot. The same side chain filter section as previous versions has been retained. The Phoenix is a stereo compressor, which can be used as a pair of mono compressors. It has a ‘soft knee’ or ‘variable mu’ characteristic in that the compression ratio increases with the amount of compression being used. Initial compression is 1.2:1 increasing to 5:1 at 15dB compression.The Phoenix is being updated continually and this unit is the Master version (suffix M) with higher stability and faster release than earlier models. A side chain filter has now been added to provide 75Hz & 150Hz, but more permutations are possible when the MC is used in stereo mode with the link switch engaged.The Master Phoenix is easier to recall as it has a mixture of indented and switched controls and the screwdriver adjustment on the chassis behind the meters controls the current through the valves on this unit, so this corrects to some extent for valve ageing. A screwdriver is supplied with the Master Phoenix and should be used periodically to adjust the meters to zeroStepped Input & Output controls * 6 position switched attack control * 7 position switched release control * 11 position switched threshold control

The P38 is a stereo mastering and record production compressor with advanced optical compression, in a substantial 2U rack mounting format. It has balanced line inputs operating at line levels.        FEATURES Soft clip function Stereo width control Transient release control Switchable input/output metering 4 position model switch Balance control Ultra gain switch

The Avalon VT737 SP Tube Voice Channel, delivers impeccable clarity with tube warmth and presence for your mic, instrument or line mono channel.The Avalon VT737 SP Mono Mic Pre/Compressor/EQ is a combination tube preamp, opto-compressor and sweep equalizer, with output level and VU metering in 2 rackspaces. Balanced mic, front-panel instrument DI, and balanced line inputs. Class A preamp uses 2 cascaded, dual vacuum-tube triodes configured with minimum negative feedback. The Avalon Vt 737sp has a high-gain switch, high-pass filter, and hardwire relay bypass..The main features of the Avalon VT737 SP include: Tube preampOpto-compressorSweep equalizerOutput level controlVU meteringBalanced mic input, front-panel instrument DI, and balanced line inputsHigh-gain switchHigh-pass filterHardwire relay bypass The main specifications of the Avalon VT737 SP include:Circuit topology: 4 dual triode vacuum tubes (Sovtek 6922), high-voltage discrete Class AGain Range Microphone: Transformer balanced 850/2500 ohm, 0dB to +58dB Instrument: Unbalanced 1 meg ohm, 0dB to +30dBLine: Balanced Class A 20k ohms, -27dB to 28dBMaximum input level and connector types: Microphone26dB@25Hz, +30dB@1kHz balanced XLR Instrument+30dB unbalanced front panel jack socketLine +36dB balanced XLRMaximum output level: +30dB balanced 600 ohms, DC coupled, discrete Class AOutput type and gain: XLR connector, output trim gain -45dB to20dBNoise 20kHz unweighted: -92dBNoise microphone EIN: -116dB, 22Hz-22kHz unweightedDistortion THD, IMD: 0.5%Frequency response -2.5dB: 10Hz-120kHz input filter includedFrequency response -3dB: 1Hz-200kHz line in-outVU meter and gain reduction: High quality illuminated OVU =+4dB and gain reduction to -20dBHigh cut filter: Variable 6dB per octave 30Hz-140HzCompressor type: Optical passive attenuator incorporating twin vacuum tubes and stereo linkThreshold - Ratio: Threshold variable -30dB to +20dB, ratio-compression variable 1:1 to 20:1Attack - Release: Attack variable 2mS to 200mS, release variable 100mS to 5 secondsEqualizer type: Discrete Class A, variable active and switched passive designFrequency bands (4): Treble - switched 10kHz, 15kHz, 20kHz, 32kHz, +/-20dB range, shelf High mid - variable 200Hz-28kHz and 2kHz -28kHz, +/-6dB range, hi-lo Q Low mid - variable 30Hz-450Hz and 300Hz-4k5Hz, +/-16dB range, hi-lo Q Bass - switched 15Hz, 30Hz, 60Hz, 150Hz, +/-24dB range, shelfAC power: Internal toroidal 100v to 240v, 50-60Hz selectable, 75 watts maximumDimensions: 19 x 12 x 3.5 in (482 x 305 x 89mm)Weight: 22lbs. (10kg)