Fredenstein V.A.S. User manual

V.A.S.
Compressor
Operating Manual

Fredenstein V.A.S. Compressor
The V.A.S Compressor is single channel FET compressor with Stereo link capability. It
incorporates Fredenstein's proprietary Re erse-Mancini FET architecture for increased linearity and
noise performance. In addition, the output stage consists of our high performance OPA2 discrete
operational amplifier coupled to a high quality American-made steel core transformer.
As all Fredenstein products, the OPA2 is not a copy of an older design, but a completely new
circuitry manufactured in SMT technology. Matched and integrated dual input transistors guarantee
astly impro ed specifications compared to older designs. The OPA2, following the tradition of
well known manufactures, is socketed and can be exchanged without tools. The industry standard
pin-out makes it compatible with many manufactures. To achie e the highest sonic performance, no
polarized capacitors, electrolytic or tantalum, are deployed in the signal path.
O erall the V.A.S Comp supports a wide ariety of different sounds from smooth and clean to
aggressi e and smashed. As a truly flexible compressor, it features rotary controls for Input Gain,
Attack Time, Release Time , Compression Ratio, Side-Chain Bandwidth, Make-up Gain, and Wet-
Dry mixing as well as illuminated switches for Bypass, Stereo link, and Side-Chain filter.
Controlling the operation of the V.A.S. Comp is ery easy due to its separate 12 LED Gain-
Reduction and Output-Le el meters. Gain reduction is indicated ranging from 1 to 16 dB and the
output-le el in the range from -30 dB to +20dB (0 dB = +4 dBu).
Other professional features are a hard bypass when powered off and a three second turn-on delay to
suppress pops, as well as a remote Bypass function in Stereo link mode. Only one Bypass switch
has to be engaged to put both units in Bypass mode for easy Stereo sound comparisons with or
without compression.
For easy touring and recording around the world, the V.A.S. Comp has a built-in uni ersal power
supply ranging from 90Vac to 240Vac, 50 -60 Hz.
As all Fredenstein products, the V.A.S. Comp is designed by a German-American team and
manufactured in Taiwan.
Fredenstein V.A.S Comp Manual V1.1 Oct. 2, 2014 Page 1

Fredenstein V.A.S. Compressor
Installation:
Electrical Safety Warnings:
Do not open t e enclosure, azardous voltages are present inside!
T ere are no user serviceable parts inside.
If you need to replace t e mains fuse, make sure t e replacement as t e same
rating (0.5AT 250V).
Rear View:
Please connect your audio inputs and outputs first to the XLR or TRS connectors
located on the back panel. If you own two V.A.S. Comps, please insert a standard
TRS cable into link connectors on both units. Connect the mains cable to the V.A.S.
Comp and then to a grounded mains outlet. The power ON/OFF switch is located on
the back panel near the power cable connector (IEC). After the unit is powered on,
the PWR indicator on the front panel will be illuminated.
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Fredenstein V.A.S. Compressor
Front View:
Rotary Controls:
B-WIDTH : Side-Chain Filter control, fully clockwise no filter, counter clockwise
2KHz to 20KHz Bandwidth
INPUT GAIN : Sets the line le el gain in the range from -10 to +20dB
COMP ATTACK : Sets the attack time of the compressor
Range from 0.5 to 50ms
COMP RELEASE : Sets the release time of the compressor
Range from 70ms to 2.5s
COMP RATIO : Sets the compression ratio
Range from 2:1 to 20:1
MAKE-UP : Output le el control of the compressor
Range from off to 0dB to +20dB
MIX : Output-Mixer, turn the control all the way counter clockwise and only
the compressed signal is present on the output (wet position), all the
way clockwise, only the input signal is present at the output (dry
position)
Switc es:
FILTER : When the switch is lit (green), the side-chain filter is acti e, if not lit,
no filter is acti e and the position of B-WIDTH potentiometer does
not matter
LINK : When lit (blue), it enables the Stereo linking of two V.A.S. Comps
when a TRS link cable is inserted on both units and both LINK
switches are turned on. Both channels will ha e identical gain
reduction to a oid shifting of the Stereo balance.
BYPASS : When the switch is lit (orange), the V.A.S. Comp is in bypass mode.
A hard bypass connects the input and outputs. If Link is turned on on
both units and a link cable is inserted, the Bypass function of the
second unit will follow the first. Please note, that in Bypass mode the
gain reduction and output meters are still acti e.
Connectors:
INSERT : Standard TRS insert connector (Ring = Output, Tip = Input) to insert
effect equipment or inject different signals into the side-chain
Fredenstein V.A.S Comp Manual V1.1 Oct. 2, 2014 Page 3

Fredenstein V.A.S. Compressor
Operation:
Like most FET compressors, the Fredenstein V.A.S. Compressor features a fixed threshold. The
compression depth is controlled by changing the input gain. Increasing the input gain will cause the
compressor to apply an increased gain reduction. The compressor Make-up control is used to
compensate for the gain reduction. The maximum compressor Make-up gain is 20 dB.
The ATTACK TIME and RELEASE TIME controls define how fast the compressor reacts and how
fast it falls back after the signal is lower than the threshold. The perfect alues are depending on the
instrument and the sound you want to achie e.
The COMP RATIO control sets the relationship between input and output le el for signals abo e
the threshold and can be aried from 2:1 to 20:1. A ratio of 20:1 is considered a limiter.
A special feature of the V.A.S Comp is its integrated output mixer which dramatically boosts the
ersatility of the de ice and so called dry/wet mixes can be performed (also called parallel
compression). The dry signal (uncompressed) and the wet signal (compressed) can be mixed
together in any relationship to achie e special sounds.
The side-chain filter allows to exclude frequencies from being compressed, e.g. to a oid pumping
on bass drums.
With the optional rack mount kit, two V.A.S. de ices can be mounted together to form a 19 inch 1U
enclosure (table feet need to be remo ed).
Tec nical Data:
Frequency Response : 20 Hz – 20,000 Hz, +/- 1dB
Make-up Gain : + 20 dB
Distortion : < 0.05%
SNR : 90 dB (at 0dB make-up gain)
Input Impedance : > 4 KOhm
Max. Input Le el : + 26 dBu
Output Impedance : 600 Ohms
Max. Output Le el : + 26 dBu
Input Attenuator : - 20 dB
Side-Chain Filter : 6 Hz to 2KHz (sweepable)
Attack Time : 0.5 ms to 50 ms
Release Time : 70ms to 2.5s
Compression Ratio : 2:1 to 20:1
Mains Voltage : 90 Vac to 240 Vac, 50 – 60 Hz
Power Consumption : 25W max.
Dimensions:
L x H x D (with feet) : 200 mm x 51 mm x 170 mm
L x H x D (without feet) : 200 mm x 44 mm x 170 mm
Weight : 1300 g
Fredenstein V.A.S Comp Manual V1.1 Oct. 2, 2014 Page 4

Contact Info:
Fredenstein Professional Audio
by Orion Communication
7F-1, No. 582, Ruei Guang Rd.
Neihu District
Taipei 114
Taiwan
Phone : + 886-2-2657-2618
Email : [email protected]
Web : www.fredenstein.com