Rupert Neve Designs Portico 543 500 Series Compressor #E0608 (Used)

The Rupert Neve Designs Portico 543 Mono Compressor delivers the unobtrusive, musical-sounding dynamic control along with brick-wall limiting found in the iconic Portico 5043 module in the 500 Series format. The RND 543 features a fully controllable VCA compressor-limiter with the Peak/RMS detection, feed-forward/feed-back modes, and a built-in sidechain high-pass filter. With a proven heritage and tremendous feature set, the Rupert Neve 543 yields a combination of rich warmth, precision, and flexibility that will resonate in the ears of sound engineers around the world.

TRADITIONAL RUPERT NEVE DESIGNS IN A NEW FORM

Built around Rupert Neve’s custom transformer designs, each 543 500 Series module encompasses individually controllable attack, release, threshold, makeup gain reduction, ratio, unity gain, sidechain HPF, Feed-forward/Feed-back selection, and Peak/RMS detection modes. With the diode bridge compressor inactive, the Rupert Neve Designs 543 may be used as a high-performance, transformer-coupled line amplifier. Two Portico 543s can be linked for stereo operation. The 543 chassis is built to standard 500 Series pro audio specifications with power and I/O provided by the 500 Series rack.

BEST FEATURES OF THE PORTICO 543

One of the more unique features of the Rupert Neve Designs 543 is the new Peak/RMS mode that can also be found in the Portico II Channel. This connectivity switch allows the VCA (voltage control amplifier) to combine with both RMS (Root Mean Square) and its peak levels. The Portico RMS circuits are considered the best to mimic the way the ears perceive loudness, while peak circuits in this 500 Series mono compressor tend to respond directly to the waveform voltage, which can be more of a concern for the user’s prevention of clipping and maximizing levels. In this instance, peak mode uses a combination of both these methods to get the best of both while avoiding the drawbacks of each method independently.

The RND 543 compressor also has the ability to change between feed-forward and feed-back modes. In most of Rupert Neve’s earliest designs, the feedback detection – controlling the VCA with a resolved voltage from the RND Portico’s output – was intrinsic to the musical dynamic response. Instead, the very nature of a gain reduction feedback compressor limits the overall attack time of the 500 Series compression circuit. To offer a faster and more technically accurate response times, with feed-forward detection that was implemented on Rupert Neve’s more modern designs. With this 500 Series rack’s FF/FB switch, both the classic and modern VCA responses are available.

FEATURES:

• THRESHOLD: Sets level where the compressor may begin to react from -30 dB to +20 dB. Minimal or no compression is with this control fully clockwise and it gets more sensitive and tends to cause more gain reduction as the knob is rotated counter-clockwise (which may be counter-intuitive to some).

• RATIO: Sets the “slope” of the compression from 1.1:1 (minimal) to 40:1 (Limit) . For example, if set for 3:1 and the input signal rises by 3dB, the output signal will only rise by 1dB. In general, low ratios can not damage the music as much as high ratios but high ratios may be more useful to minimize clipping and OL lights in the recorder.

• COMP IN: Engages the compressor section of the unit.

• F/F + F/B: These are two very different compressor modes, FEED FORWARD and FEED BACK. The F/B mode (button in) tends to sound smoother and often more natural and tends to be quicker to set up. The F/F mode can be more useful for shaping the envelope of the sound and introducing more bounce and pumping in time with the song, when that is the goal.

• GAIN: Continuously variable from -6 dB to +20 dB.

• ATTACK: This sets how quickly the compressor reacts and starts attenuating. Continuously variable from 20mS to 75mS.

• RELEASE: This sets how fast the compressor returns back to zero after attenuating. Typically engineers use slower release times when the intention is to minimize any obvious compressor action or gains changing. Continuously variable from 100mS to 2.5 Seconds.

• RMS/PEAK: This changes the compressor from essentially responding to the RMS level of the audio to also responding to the PEAK level. RMS (root mean squared) circuits are considered to better mimic the way the ears perceive apparent loudness, while Peak circuits tend to directly respond to the waveform voltage which may be more of a concern for prevention of clipping and maximizing levels.

• SIDECHAIN HPF: This routes a high pass filter set to 250 Hz into the circuit that the compressor uses to determine level. Note that the rest of the circuit and output will not have those lows filtered out – this only determines the portion of the signal that is affected by the compressor. This is very useful when you want your low frequency content to come through unaffected while still compressing the mids and highs.

• LINK: When link buss is provided by the 500 series rack, this can be used to link the reduction of two 543 units together.