Symetrix 506E, Руководство пользователя

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Symetrix 506E Headphone Amplifier User’s Guide
Calculating the Maximum Amplifier Load
The minimum operating impedance,
or maximum load, for each output of
the 506E is 8 ohms. Use as many
pairs of headphones as desired, as
long as the total combined impedance
(per output) does not fall below 8 ohms.
| Making Hardware Connections and Selections | Setting Gain Controls
| Calculating the Maximum Amplifier Load
How Many Headphones of Various Impedances May Be Used
With Each Output of the 506E
IMPEDANCE OF HEADPHONES MAXIMUM NUMBER/CHANNEL
8 1
16 2
32 4
100 10
200 20
400 40
600 60
If You Are Driving Low Imped-
ance Headphones
The quantities noted above reflect
usage with typical wide-range musical
signals. If you are driving low-
impedance headphones (16 ohms or
lower
actual impedance), and you
intend to drive them to the brink of
amplifier clipping, then you should
revise the number of headphones
possible to 2 headphones at 8 ohms
or 4 headphones at 16 ohms. In the
example of 8 ohms, you’ll have 2
amplifier channels that aren’t doing
anything. It is OK to use any remain-
ing amplifier channels with higher
impedance phones (50 ohms or
higher).
For maximum output with all chan-
nels driven, try to restrict the lowest
combined load impedance to 50 ohms
per channel. Lower impedance loads
simply reduce the maximum output
possible.
If You Are Using Headphones
Spec’d for 8 Ohms Output
Many headphones are spec’d as being
suitable for 8 ohm outputs. They are,
but this does not mean that their
actual impedance is 8 ohms. In most
cases, the actual impedance is
substantially higher. This is good
(rather than bad). For whatever it’s
worth, most decent headphones have
actual impedances ranging from
50 ohms and up.
If You Are Using Multiple
Headphones
When multiple headphones are
required with each output, use
headphone type “Y” cords, or a
“breakout box,” such as the Symetrix
HR-1 Headphone Remote. A breakout
box may have as many paralleled
1/4" stereo jacks as necessary, as
long as the total combined impedance
(per output) does not fall below
8 ohms.
CAUTION
The 506E is capable of driving many
headphones past the threshold of
pain. At this volume level, hearing
damage can occur. For your own
hearing health, monitor at a low
sound pressure level.
Fast First-Time Setup