Henry Engineering Studiodrive User Manual

TM

STUDIODRIVE

Integrated PC Studio System

HENRY ENGINEERING

503 Key Vista Drive

Sierra Madre, CA 91024

Tel: [phone]

Fax: [phone]

www.henryeng.com

1.0 DESCRIPTION

StudioDrive is a professional stereo audio system that can be installed in the drive bay of a personal computer
(PC). StudioDrive provides the source control, mixing, and monitoring functions of a professional broadcast audio
console to create a complete self-contained studio that is ideal for live broadcasting and audio production tasks.

StudioDrive accepts up to 6 audio sources via 4 mixing channels. There are inputs for a studio microphone, three
stereo line level sources, a dedicated input for the PC soundcard, and the built-in telecoupler for recording audio
(news feeds, actualities) from a standard POTS line.

StudioDrive has two pair of stereo outputs for live broadcasting and recording to the PC soundcard or other
recording device. Accurate LED VU meters monitor the Program output level. A monaural Mix-Minus output is
provided for use with any external telephone hybrid.

The Monitor and Headphone system allows StudioDrive to monitor (a) the Program output, (b) playback from the
soundcard or (c) the off-the-air signal from the station demodulator.

StudioDrive consists of the main control unit which is installed in the PC’s drive bay, and the Audio Interface unit
that contains the power supply and all I/O connections. The Audio Interface unit can be attached to the back of the
computer case or mounted to a tabletop or wall. The two units are interconnected with a flat cable, which is routed
through the back of the computer. An optional Desk Mounting Kit allows StudioDrive to be desk-mounted, for use
with a laptop computer (or for non-PC applications) or if it is not possible to mount the main control unit in the PC.

Any soundcard with either balanced (professional) or unbalanced (consumer) analog I/O can be used with
StudioDrive to create an integrated and self-contained broadcast and production facility.

2.0 INSTALLATION StudioDrive should be installed by a qualified engineer or technician.

StudioDrive can be installed in the drive bay of a PC or desk mounted using the optional Desk Mounting Kit.

Before installing StudioDrive in the PC, the complete system should be programmed, connected, and calibrated to
all peripheral studio equipment. Only after proper operation is verified should StudioDrive be installed in the PC.

2.1 USER PROGRAMMING

Before StudioDrive is installed, the user must set some internal jumpers to optimize the unit for the peripheral
equipment with which it will be used. JP1 thru JP9 are located on the StudioDrive circuit board.

JP1 and JP2 set the input sensitivity for Line Input #2. Set them to HI if the source equipment is balanced and
operates at about 0 dBu. Set them to LO if the source is unbalanced and operates at -10 dBv.

JP3 and JP4 set the input sensitivity for the PC soundcard (playback) inputs. Set them to HI if the PC soundcard is
balanced and operates at about 0 dBu. Set them to LO if the soundcard is unbalanced and operates at -10 dBv.

JP8 and JP9 set the input sensitivity for the Air monitor inputs. Set them to HI if the Air monitor signal is balanced
and operates at about 0 dBu. Set them to LO if the Air monitor signal is unbalanced at -10 dBv.

JP5 sets the Monitor Muting function. Set it ON if the Monitor system should mute when the mic is on. Set it OFF
to defeat the muting feature. (Use this mode only if mic is in an acoustically isolated “announce booth” or studio.)

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JP6 and JP7 determine what the Monitor system “hears” when the unit is in the PC-Record mode. Most

soundcards provide an audio output when the card is in the Record mode. When StudioDrive is in the PC-Record
mode, the Monitor system monitors the output of the PC soundcard so the operator can hear the effects of mixing
or editing on the PC. Set JP6 and JP7 to COMP for this mode of operation.

If the PC soundcard does not provide audio when the soundcard is in the Record mode, JP6 and JP7 should be set
to REC. This will allow the operator to monitor the RECORD output, which feeds the soundcard input.

There are also two jumpers located in the Audio Interface unit.

JP1 enables the Mic Process Insert function. If external mic processing equipment will be used (via PROC

INSERT jack on Audio Interface unit), set the jumper to ON. If mic processing will not be used, set it OFF.
(This is the factory default setting.)

JP2 enables remote on/off control of the mic. If a remote mic on/off or “cough switch” will be used, set the jumper
to ON. If no remote mic control will be used, set it OFF. (This is the factory default setting.)

2.2 CONNECTING TO PERIPHERAL STUDIO EQUIPMENT

StudioDrive audio connections are made via the Audio Interface unit. The block diagram below shows a typical
installation. All connections, except the Mic input, use T-R-S (“stereo”) ¼” phone plugs.

MIC COMP / EQ TELE CD PLAYER D.A.T. MINIDISC AIR MONITOR

MONITOR

MIC IN MIC PROCESS TEL IN LINE 1 IN LINE 2 IN LINE 3 IN AIR MON

StudioDrive

All I/O connections via Audio Interface

unit except for Line 3 input.

MIC TALLY COUGH SW. RECORD OUT PC IN MIXMINUS OUT

WARNING LIGHTS COUGH SW. COMPUTER SOUND CARD TELE HYBRID
(SUPERELAY) (N.O.) (LINE IN / OUT) (IF USED)

MIC INPUT Input for professional microphone. XLR: Pin 1 = GND, Pin 2 = HI, Pin 3 = LO.

MIC PROCESS Insert point (unbalanced) for external mic processing equipment, e.g., limiter, EQ, etc.

TIP = Output from processor to mic chan. input, RING = mic preamp output to processor, S = GND.

Levels to / from mic processor should be -5 dBu. Note: JP1 in Audio Interface unit must be ON.

LINE 1 L+R Line input #1 is for an unbalanced stereo source @ -10 dBv (levels up to 0 dBv are OK).

TIP = LEFT, RING = RIGHT, SLEEVE = GROUND

MONITOR OUT

PROGRAM OUT

SYSTEM

TO
TRANSMITTER

TO TELCO LINE

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The following line level inputs should be wired as follows: TIP = HI, RING = LO, SLEEVE = GND.
For unbalanced sources connect the RING and SLEEVE together.

LINE 2 LEFT Line input #2, left channel. Input sensitivity set by JP1.
LINE 2 RIGHT Line input #2, right channel. Input sensitivity set by JP2.
P.C. LEFT Input for PC soundcard playback, left channel. Input sensitivity set by JP3.
P.C. RIGHT Input for PC soundcard playback, right channel. Input sensitivity set by JP4.

AIR MON LEFT Input for Air monitor, left channel Input sensitivity set by JP8.
AIR MON RIGHT Input for Air monitor, right channel Input sensitivity set by JP9.

TEL Connect to POTS line to record caller audio. TIP = RED, RING = GREEN, SLEEVE N/C
Note: the telecoupler bridges the telephone line. A standard telephone should also be connected
to the line to seize (terminate) the line while recordings are made (for recording caller audio only).

Note: A telephone hybrid must be used if both the caller and host are to be recorded or broadcast,
e.g., for a “talk show”. In this case, the hybrid’s caller audio output may be fed to the TEL input.

MONI L+R Unbalanced output to studio monitor system. TIP = LEFT, RING = RIGHT, SLEEVE = GND.

MIX MINUS Unbalanced output to feed “send” input of hybrid, if used. TIP = HI, SLEEVE = GND.

The following balanced outputs should be wired as follows: TIP = HI, RING = LO, SLEEVE = GROUND.
For unbalanced loads, connect to TIP and SLEEVE ONLY. DO NOT SHORT RING TO GROUND!

PGM LEFT Main Program output, left channel, on-air feed. (0 VU = +4 dBu)
PGM RIGHT Main Program output, right channel, on-air feed. “
REC LEFT Record bus output, left channel, to input of PC soundcard. (Output level adjustable.)
REC RIGHT Record bus output, right channel, to input of PC soundcard. “

TALLY/COUGH Logic circuits for mic control and On The Air warning light control:
TALLY: Provides +12 volts between TIP and SLEEVE when Mic is on. Connect to Henry
` Engineering Superelay DC control inputs to activate warning lights when Mic is on.
COUGH: Connect an external N.C. switch or pushbutton between the RING and SLEEVE to
control Mic. Opening the circuit turn Mic off; closing circuit turns mic on.
Note: JP2 in Audio Interface unit must be ON to enable remote Mic on/off control.

2.3 RECORD OUTPUT LEVEL CALIBRATION

Plug the flat cable from the Audio Interface unit into the header on the StudioDrive chassis. Be sure that the RED
STRIPE on the cable is at the right end of the header,
After all audio connections have been made the system can be powered up. Calibration consists of adjusting the
StudioDrive RECORD OUTPUT level to match in input sensitivity of the PC soundcard.

Average vs. peak levels

All PC recording/editing software has some type of on-screen audio level meter. Some meters read average levels,
while others read peak levels. The purpose of the meter should be to show average perceived level, so that all
recordings will play back at a consistent perceived level. Unfortunately, some on-screen level meters actually read
absolute peak levels. While this is useful to prevent system overloads, peak-reading meters are of little use in
determining average perceived level. Check the manual for the software being used to determine what the on­screen meter indicates.

The best way to calibrate a PC soundcard recording system is to determine the maximum operating level (“clipping
point”) for the system, then establish 0-VU at 15 to 20 db below the clipping point. This will ensure adequate
headroom above 0-V U for distortion-free audio peaks. Note: StudioDrive’s clipping point is 20 dB above 0-VU.

To calibrate record levels, feed a test tone (about 400 Hz) into any StudioDrive line input. Carefully set the level so
that the amber “0-VU” LED is lit. (This produces exactly +4 dBu at the Program outputs.)

Now put the soundcard into the RECORD mode. Adjust StudioDrive’s REC CAL trimmers to produce the
appropriate level into the soundcard. The REC CAL trimmers are at the back of the StudioDrive PC board.

as viewed from the rear of the StudioDrive chassis.