Behringer T1953 User Manual
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TUBE ULTRAGAIN T1953
4.6 The best of both worlds
Despite many efforts neither manufacturers nor developers have succeeded so far in simulating these positive
properties of the tube by means of other devices. Additionally, the natural capabilities of the tube to act as a
soft limiter can only be mimicked with highly sophisticated circuitry. Todays studio technology requirements
are therefore met by a combination of both high-grade semiconductor and tube technologies. In this context,
tubes no longer serve their original purpose as amplifiers, but are used for the detailed shaping of sound.
4.7 UTC circuit
In
Out
WARMTH
Fig. 4.7: UTC circuit
The TUBE ULTRAGAIN splits up the audio signal applied at the input and processes it differently for both
signal paths. Each of the two tube halves amplifies the original signal and the signal modified in its phase
spectrum (twin triode). Additional harmonics are produced by slightly overdriving the tube stage. When the two
signals are processed by the UTC circuit, the interference noise found in conventional tube circuits can be
largely eliminated, and the actual tube effect be added gradually. The more you turn the Warmth control to the
right, the more tube sound will be added to the original signal.
4.8 Studio applications
In a recording studio tubes do not perform the same task as they do in an overdriven guitar amp, where the
considerably higher saturation of the tube(s) leads to a full and often deliberate modification of the input signal
(in many cases combined with a heavy increase in noise floor levels). In the studio more subtle effects are
needed. Here, tube circuits add life to the signals tonal character and increase its power to make itself heard.
Often, tubes also increase the signals perceived loudness (in relation to the unprocessed signal), i.e. the
perceived loudness goes up although the volume level remains the same. This is because the dynamic range
of the applied audio signal is limited by the tube circuit, while the amplitude of the signal with the lowest
loudness is raised. Thus, increasing tube saturation produces a slight compression effect over the entire
dynamic range.
A similar effect can be perceived when analog tape is saturated. This saturation effect also compresses the
recorded audio material and produces additional harmonics.
4. TECHNICAL BACKGROUND