VS AND VSO
IMPEDANCE MATCHING
STEREO VOLUME CONTROLS
INTRODUCTION
The ELAN VS and VSO are 12-step stereo volume controls with
selectable impedance match settings of 1X, 2X, 4X, and 8X,
allowing you to connect multiple speakers to an amplifier without
going below the amplifier’s minimum load requirements.
ROUGH-IN
The VS fits easily into the majority of 18 cu. in. single-gang boxes
and P-rings. The VSO’s enhanced features (Override and Home
Theater Mode) requires the use of a slightly larger circuit board
and must be matched with a compatible box or cover plate (see
diagrams and list of compatible boxes on package insert card). If
local building code allows, use of P-rings provides for easier instal-
lation, as access to the full depth of the wall is unobstructed.
Although some local building codes allow low voltage devices
such as volume controls to be enclosed in the same electrical
boxes as 110 volt devices, ELAN does not recommend this as
interference in the form of hum or buzzing may be introduced to
the audio signal. For the same reason, do not install volume con-
trols adjacent to high wattage light dimmers.
WIRING
The VS and VSO can accommodate from 14 to 24 gauge speaker
wires. 18-gauge wire is suitable for most applications. Heavier
gauge wire should be considered for a longer wire run. In-wall wire
runs are also subject to local code fire rating requirements. Always
use stranded, twisted-pair, copper speaker wire for in-wall wire
runs. Never use lamp or zip cord for in-wall wire runs.
• Always check local building and fire rating codes for low
voltage device installation & wiring requirements.
• In retrofit installations, always check for obstructions such as
pipes, conduit or electrical wiring before cutting into drywall.
SELECTING THE CORRECT IMPEDANCE MATCH
Configurable jumpers on the VS and VSO determines the imped-
ance match setting of the volume control. What jumper position
should be selected depends on three things:
1) the minimum impedance rating of the amplifier being used,
2) the number of speakers being connected to the amplifier channel,
3) the impedance of the speakers being connected to the
amplifier channel.
Once all of the above has been established, all it takes is some
simple math to determine the system impedance, and thus the
impedance match settings for the volume control.
SERIES
Only two simple equations are needed:
Impedance Rating of Speakers
# of speakers connected to channel
Amplifiers Minimum Impedance Rating
System Impedance
EXAMPLE
If the amplifier’s minimum impedance rating = 8 ohms, and you
wish to connect four 8 ohm speakers to an amplifier channel:
8 OHM SPEAKERS
4 SPEAKERS
8 OHM AMPLIFIER
2 OHM SYSTEM IMPEDANCE
Most speakers are rated at 4, 6 or 8 ohms. If connecting speak-
ers of different impedances to an amplifier, an average impedance
must be determined; i.e. one pair of 4-ohm speakers is the equiv-
alent of two pairs of 8-ohm speakers. 6-ohm speakers should be
entered into the equation as 4-ohm speakers. All volume controls
connected to the amplifier should have the same impedance
match setting. Never go below an amplifier’s minimum impedance
rating as this can cause damage to the amplifier. Both the VS
and VSO have minimum impedance ratings of 4 ohms. If con-
necting more than one speaker to the VS or VSO make sure not
to exceed this minimum.
HOME THEATER MODE (VSO Model Only)
You are in your Home Theater. You are enveloped in sound as
your favorite movie comes roaring through speakers all around
you. There’s someone at the front door, or someone in the house
is trying to page you. The rear channel speakers in your home
theater automatically switch to ELAN page or doorchime audio (not
all the speakers, interrupting everyone’s listening enjoyment––just
the rear speakers!), then revert back to the movie soundtrack
when the page or doorchime has ended. That’s Home Theater
Mode.
In this mode, the VSO becomes a completely passive device.
Moving the jumpers to the SSP (Surround Sound Processor) posi-
tion by-passes the volume control’s rotary switch and autoformers.
The knob on the volume control will not effect the level of your
rear channel speakers. The rear channel power rating of your
surround sound processor will not be an issue. Nor will the con-
trol introduce any unwanted noise or signal degradation into your
high-end home theater. And because it is passive, the VSO can
be “buried” out-of-sight behind your surround sound processor or
back where your ELAN components are located.
Consult the VSO wiring diagram on the reverse side or your
ELAN systems installation manual for hookup and wiring dia-
grams.
The PATENTED ELAN OVERRIDE FEATURE
––VSO Model Only
Our volume controls with the override feature permit ELAN sys-
tem paging and doorchimes to be heard even if the volume con-
trol is turned to the off position. To do this, the VSO Stereo
Volume Control with Override requires a control voltage to trig-
ger the relay incorporated into the VSO’s design. The control volt-
age originates from an ELAN controller any time a page or door
chime is initiated.
Wiring Requirements For Override
For Volume Controls with override, use CAT5 phone wire for the
connection of the 12VDC signal distribution. Consult the wiring
= System Impedance
= Impedance Match
Jumper Setting
= 2 OHM SYSTEM IMPEDANCE
= 4X JUMPER SETTING
