SPL Iron V2 Two-Channel Tube Mastering Compressor (Black/Silver) - Manual (Page 7)

7
Technical Aspects
120V technology – Comparison
Most audio devices work with an internal operating voltage of +/-15 volts and can thus
process a maximum input level of +21.5 dBu. If a DAC, for example, has an output level of
+22 dBu at 0 dBFS, level peaks of the music material would already cause overloads in
the input stage of the device. All components in the audio device often operate at their
limits.
SPL devices with 120V technology can handle input levels of +32.5 dBu thanks to the
higher internal operating voltage of +/- 60 volts – thus offering 12 dB more headroom.
All components consequently operate continuously in the optimum operating range. The
result is a very pleasant, natural and relaxed sound experience.
These diagrams clearly show the superiority of the 120V technology in comparison to
other circuits with lower, common operating voltages.
The direct relation between operating level and maximum level is fundamental for the
classification: the higher the operating level, the higher the maximum level a circuit can
handle. And since virtually all essential acoustic and musical parameters depend on this
relation, a higher operating voltage also has a positive impact on the dynamic range, dis-
tortion limit and signal-to-noise ratio.
Do bear in mind that dB scales do not represent linear but rather exponential increases. A
3 dB increase corresponds to doubling the acoustic power, +6 dB correspond to twice the
sound pressure level, and +10 dB correspond to twice the perceived loudness.
120
125
130
135
140
145
dB
124,2
141,4
120 V 30 V
Dynamic Range
0
5
10
15
20
25
30
35
dBu
21,5
33,2
Maximum Levels
120 V 30 V
0
20
40
60
80
100
120
Volt
Voltage
120 V 30 V
-115
-113
-111
-109
-107
-105
dBu
-106
-114,2
THD&N
120 V 30 V
When it comes to volume, the 120V technology exhibits a performance that is twice that
of common components and circuits, in regard to maximum level and dynamic range,
with values that are approximately 10 dB higher. THD measurements of the the 120V tech-
nology more than 8 dB better than a device with a operating voltage of 30V.