Manley Mastering Stereo Variable Mu Limiter Compressor Hi Pass Mod

The Mastering Version of the Manley Variable Mu Limiter Compressor incorporates detented and logable steps, built with 1% metal film resistors on sealed gold-contact Grayhill switches. The Manley Variable Mu Limiter Compressor has been Manley's best selling product for many years. It is one of the very few compressors that have 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. It works by using the "remote cut-off" or re-biasing of a vacuum tube to achieve compression. The highly revered vintage Fairchild 670 also uses this technique, and is one of few all-tube compressors to do so. Even the side-chain has glowing rectifier bottles. How's it work? The unique 5670 dual triode is at the center of the peak-reduction 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 a soft-knee 1.5:1 ratio, while the sharper knee Limit mode starts at 4:1 and moves to a more dramatic ratio of 20:1 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. 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 can always adjust individual source levels elsewhere, right? The advantage of the stereo input control becomes dramatically clear when 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 music a big hug. Manley Variable Mu Modifications: - High-Pass Side Chain option: Also available on the mastering version of the Variable Mu (#620909), this adds two switches to the front panel, one for each channel, so that when engaged, the side chain will not respond to frequencies lower than 100Hz. (100Hz is standard as the -3dB point. Other frequencies can be custom-ordered.) This HP SC Mod can be used with music with heavy bass lines or bass-heavy mixes where don't want the bass driving the whole action of the compressor. The filter is a very gentle 6db per octave 1 pole filter, and will typically be down 1-3db at 100 Hz, and down 4-6db at 50Hz. As decrease the frequency the amount of limiting will decrease also. At the extreme LF (<20hz) there should be very little gain reduction going on. The purpose of the filter is to keep very LF stuff (like a heavy kick drum) from activating the compression/limiting so that the overall level doesn't duck with every drumbeat. Mid-Side mod (Vertical/Lateral or Sum/Difference): This modification opens the door to stereo encoding and decoding, as well as exciting image-enhancement processing capabilities. For instance, setting it to compress the in-phase information only allows the augmentation of the stereo image as the out-of-phase content is left untouched. Or, conversely, if need a "more-mono" mix for broadcast, or vinyl-cutting for instance, can set it to kill off more of the out-of-phase info which leaves more in-phase material in the final result. (Read more about the M-S Mod on page 12 of the owner's manual.) Note: There is no space to add both the M-S and High-Pass mods. must choose one or the other. T-Bar mod: This modification is in response to users wanting to know if they should use the 5670 tubes or 6386 tubes