Typical Performance:
VOLTAGE LOSS (@ 1.0 kHz):
1.0 dB
INPUT IMPEDANCE:
1050 ohm @ 1.0 kHz
SECONDARY SOURCE IMPEDANCE;
270 ohm @ 1.0 kHz
TOTAL HARMONIC DISTORTION:
< .1% 30 Hz-20 kHz @ -15 dBv output
FREQUENCY RESPONSE (Re:1.0 kHz);
+.2dB @ 20 Hz
- .6dB @ 20 kHz
- 4dB @ 65 kHz
INSULATION:
> 600V winding/shield/winding
PRO CO ™ • iFace • Portable Audio Player Interface
Pro Co Sound, Inc • 225 Parsons Street, Kalamazoo, MI 49007 USA • Tel: 800 - 253 - 7360 • Fax: 269-388-9681 • www.procosound.com
Engineering Specifi cations:
The portable audio impedance-matching unit shall be suitable for
interfacing one (1) stereo unbalanced -10dBV line-level source to one (1) or
two (2) balanced or fl oating low-impedance (1.0 kohm nominal) microphone
preamplifi er inputs. There shall be one (1) 3.5mm stereo input jack, wired in
parallel to two (2) recessed RCA-type jacks. These inputs shall be provided
with a miniature rocker-type switch and resistive summing network to provide
signal combining for monaural operation as required. There shall be two (2)
Pro Co MBT-1 Microphone Bridging Transformers. The magnetic shield of the
transformer shall be connected to the enclosure. The primary electrostatic
shields of the transformers shall be connected to the unbalanced input
connectors and to the enclosure. The secondary electrostatic shields shall be
connected to pin 1 of the appropriate XLR-type output connector.
The enclosure shall be constructed in the Pro Co ”Uni-Box” design with
16-gauge steel black zinc fi nish top and bottom plates, 16-gauge black
texture powder-coated steel end plates and black anodized aluminum side
channels. Control functions shall be identifi ed by a printed Lexan top panel
overlay. Switches shall be of the miniature “rocker” type and shall be recessed.
The enclosure shall be provided with two (2) miniature handles at front and
back and four (4) non-conductive feet. The dimensions of the unit shall be
4.875” D x 4.375” W x 1.75” H (123.8mm D x 111.1 mm W x 44.4mm H).
The portable audio player impedance-matching unit shall be a Pro Co iFace.
Pro Co Model MBT-1 Transformer
The MBT-1 is a carefully designed, custom-built 1:1 microphone bridging
transformer whose characteristics are optimized for use with balanced low-
impedance microphones or similar sources.
Special winding techniques and a high-permeability (80% nickel) core
lamination preserve full frequency response while minimizing signal losses
and other “loading” eff ects. Separate electrostatic shields for primary (input)
and secondary (output) windings reduce capacitive coupling of ground-
borne electrical noise between main and stage monitor or recording mixers,
eliminating annoying 60-Hz hum and buzz. The source impedance of the
MBT-1 is very similar to that of a low-impedance microphone to ensure proper
matching to the input circuitry of the mixer. The result is clean transient
response (no overshoot or ringing) and low distortion even at low frequencies
and high input levels.
0107
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PRO CO MODEL: iFace
DIMENSIONS
WEIGHT .......... 1.25 lb
.55 kg
