Spectra Sonics 611G Guitar/Instrument Compressor/Limiter
The Spectra Sonics 611G Guitar/Instrument Complimiter is a unique high impedance guitar/instrument compressor/limiter design which is based on the legendary 610 Complimiter, (circa 1969). The 611G is a hand-built, discrete design that utilizes hand-selected components, including British made audio isolation transformer(s).
The 611G operates as an independent peak limiter, compressor, or in combination, respectively.
The 611G provides:
Dramatic improvement in dynamic range and harmonic content
Reduced distortion due to the elimination of transient overload
Improved system noise performance
Instantaneous control of dynamic range, (compression function)
Unequaled sonic performance with either passive or active instrument pickups
Under most applications, the 611G should be terminated directly to the guitar/instrument. In turn, the 611G may be terminated to other effects devices, guitar amplifiers, or console inputs.
Peak Limiting Mode
The “peak limiting” mode allows for elimination of transient overload, inaudibly. (The 611G limiter circuit operates well beyond 20 kilohertz). The peak limiter function allows for terminated input levels, to be increased 6-10dBu, without audible transient overload distortion. The improvement in reduced system noise and increased dynamic range, (signal headroom), is readily apparent. The reduction of “digital zero” overload, as related to recording and sound reinforcement is evident and easily demonstrated. Audio levels operating in the red zone of the Vu meter heretofore considered “unusual”, may be consistently accomplished with the use of the 611G. In addition, the reproduction of 2nd and 3rd order harmonic content will be enhanced by employing this device.
FRONT PANEL DESCRIPTION
INPUT PAD
The input pad controls the amount of limiting, and/or compression/limiting, that is required. The pad allows for up to 24dB of attenuation in 6dB increments.
To preserve dynamic range as well as optimum noise performance, it is strongly suggested that the guitar/instrument volume/tone control knobs be set 50% or greater with consideration given to preserving sonic quality of the instrument signal output. By systematically adjusting the instrument knobs and the input pad of the 611G, the user will establish a optimum balance between the instrument and 611G.
RELEASE CONTROL
The release control knob affects the release time after initial signal compression. Maximum release time, marked “10” on the front panel, will slowly restore gain to the original level.
SLOPE CONTROL
The slope control provides the widest range of compression/limiting ratios available, from 1.1:1, (linear amplification), to 100:1, or a flat slope. When the slope control is set for minimum compression, the knob is set at “10”, thus providing linear amplification of 20dB for input above threshold, (-40 dBu).
When the slope control is set for maximum compression, the knob is set at “0”, for a flat
slope.
THRESHOLD
A flashing threshold LED indicates transients, (peaks), at -40dBu. A constant threshhold LED indicates program material.
OVERLOAD INDICATOR
The red LED indicates audio levels beyond +10dBu.
GAIN REDUCTION LED METER
The gain reduction meter indicates compression, in dBu, relevant to input level and, or,
slope setting.
REAR PANEL DESCRIPTION
29 VDC DC POWER INPUT
FS OPTIONAL FOOTSWITCH IN/OUT CONTROL
OUT SIGNAL OUTPUT, ¼” JACK, 600 OHM, TRANFORMER
ISOLATED.
IN SIGNAL INPUT, ¼’ JACK, HIGH IMPEDANCE, 75K OHMS
NOTE: OPTIONAL INPUT TRANSFORMER AVAILABLE,
MODEL 611GX.
611G SETUP EXAMPLES
PEAK LIMITING ONLY 1.1 TO 1
Adjust 611G input pad so that threshold LED flashes intermittently and the gain reduction meter does not indicate level. The flashing “threshold” level indication should reflect maximum playing level. It is recommended
that the guitar/instrument be set at approximately 50% or higher.
Release Knob =“0”
Slope Knob =“10”
This setting should be used as a starting point for fast attack guitar requirements.
(Often called “crunch”)
COMPRESSION & LIMITING, SIMULTANEOUSLY
Adjust 611G input pad so that gain reduction meter flashes intermittently at “0”
with the input pad set at 18dB-24dB attenuation and/or increase guitar/instrument output level. To increase compression, reduce input pad attenuation. By adjusting guitar/instrument level knobs in concert with the 611G input pad level, a precise level of compression may be attained. It is recommended that the guitar/instrument be set at approximately 50% or higher.
Release Knob = “1-10”, depending upon release time required, 50ms to 10 seconds.
Slope Knob = “1-10”, depending upon amount of required compression. Setting
“1” reflects maximum compression. Setting “10” reflects minimum
compression.
Note
When employing a fast release time and an increased level of compression, resulting audible distortion may occur. Under such cases, increase release time until distortion is reduced or eliminated.
http://www.spectrasonics610.com/New_611G.html
USED GEAR PORTALS
