Audio Engineering

182 Chapter 7 7.6.5 Very Low Noise IC Op-Amps The development, some years ago, of very low noise IC operational amplifi ers, suc ...

Preamplifi ers and Input Signals 183 with the gain of the second stage amplifi er (a TL071 IC op-amp) switchable to suit the typ ...

184 Chapter 7 7.8 Input Switching .............................................................................................. ...

Preamplifi ers and Input Signals 185 unsuitable for high-quality audio equipment where such remote switching is employed to mini ...

186 Chapter 7 7.8.2 Diode Switching Diode switching of the form shown in Figure 7.15 , while employed very commonly in RF circui ...

Preamplifi ers and Input Signals 187 2K2 10 K 10 K 0.1μ 10 K 0.1μ 0.01μF 0.01μF 0.1μ 0.1μ 0V 0V 0V 0V 0V 0V 10 V IN4148 IN4148 ...

188 Chapter 7 stages. Moreover, developments in the design of such voltage amplifi er stages have allowed continuing improvement ...

Preamplifi ers and Input Signals 189 obtaining good linearity lies in the nature of the base voltage/collector current transfer ...

190 Chapter 7 lc Vb Output current swing Input voltage swing Figure 7.19 : Transistor amplifi er waveform distortion due to tra ...

Preamplifi ers and Input Signals 191 This implies that a “ push–pull ” arrangement, such as the so-called “ long-tailed pair ” c ...

192 Chapter 7 impedance of this, the lower the distortion that will be introduced by the stage, for any given output voltage sig ...

Preamplifi ers and Input Signals 193 7.10.2 Field Effect Devices Other devices that may be used as amplifying components are fi ...

194 Chapter 7 7.10.2.1 Metal–Oxide–Semiconductor Field-Effect Transistors Metal–oxide–semiconductor fi eld-effect transistors, i ...

Preamplifi ers and Input Signals 195 It is often found that the chip construction employed for junction FETs is symmetrical, so ...

196 Chapter 7 Devices of this kind, known as V-MOS and T-MOS constructions, are shown in Figure 7.28. Although these were origin ...

Preamplifi ers and Input Signals 197 layer, which destroys the device, as a result of transferred static electrical charges aris ...

198 Chapter 7 For very low noise systems, operating at circuit impedance levels that have been deliberately chosen to be as low ...

Preamplifi ers and Input Signals 199 Practical audio circuit designs will therefore regard headroom simply as one of a group of ...

200 Chapter 7 Fortunately, because the output of the compact disc player is at a high level, typically 2 V rms, and requires no ...

Preamplifi ers and Input Signals 201 be low. Q 2 , however, which is required to develop a much larger output voltage swing, wit ...