-If
You Need to Increase
the Overall Volume Levels |
| With Goldpoint stepped attenuators,
normal listening levels are typically between knob positions 9 and 2 o'clock.
But if you have to turn the knob way up before you can really hear anything,
as could happen when using a stepped attenuator in a Passive Preamp, our
"regular" stepped attenuator may be providing too much attenuation for
your system. If you want to reduce the number of silent, unusable knob
positions, here's what you need to do: |
|
| Install a resistor between
your Ground point and the Ground pad on the stepped attenuator, as illustrated
above. This resistor causes the first knob position (which would
normally be the "Fully OFF" position) to be some level above "Fully OFF".
Although this is not the optimum way to get the volume control to give
a usable listening level sooner in its rotation, it is an easy way to do
it. There would no longer be a full OFF knob position, but in some cases
this still works out just fine. |
| The following table shows
Rg1
resistor values to move the first knob position level some decibels above
full OFF: |
|
-If
You Need to Decrease
the Overall Volume Levels |
| With Goldpoint stepped attenuators,
normal listening levels are typically when the knob position is between
9 o'clock and 2 o'clock. But if you have high output level signal source
equipment (such as CD players), high gain power amplifiers, and/or very
efficient speakers, a "regular" stepped attenuator may not provide enough
attenuation for you, and you may experience the following: |
| 1) |
The
sound level is too high when turning the knob up only a few clicks - (8
o'clock, for example). |
| 2) |
Turning
the knob up past 12 o'clock makes the sound level higher than you would
ever want it to be. |
|
| If either of the above conditions
exist, a good solution is to install a pre-attenuation circuit. This adds
attenuation to the amount provided by the stepped attenuator. |
|
| The pre-attenuation circuit
(resistors Rp1 and Rp2)
attenuates the Input
signal before it reaches the input of the stepped attenuator.
If the two resistor values are chosen correctly, the Input Impedance
of the attenuator plus Rp1 and Rp2
will be the same as the Input Impedance of the stepped attenuator by itself.
This is desirable so that the signal source output has the same load as
before. |
|
|
| The following table shows
the amount of additional attenuation provided by different Rp1
and
Rp2
resistor value combinations - for use with different value stepped attenuators. |
|
|
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