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29-506: DS1 or DS-1 may refer to: BOSS DS-1 , a guitar distortion pedal Digital Signal 1 , a T-carrier signaling scheme devised by Bell Labs Deep Space 1 , a mission to 9969 Braille & 19P/Borrelly DS-1 (drug) , a selective GABA A α4β3δ agonist drug South African Class DS1 , a diesel locomotive class Datsun DS-1 , a car by Nissan, see Datsun DS Series Dark Souls , an action role-playing game Dead Space (2008 video game) ,

58-422: A common-emitter amplifier is one of three basic single-stage bipolar-junction-transistor (BJT) amplifier topologies, typically used as a voltage amplifier . It offers high current gain (typically 200), medium input resistance and a high output resistance. The output of a common emitter amplifier is inverted; i.e. for a sine wave input signal, the output signal is 180 degrees out of phase with respect to

87-580: A power supply rail ). This impedance R E {\displaystyle R_{\text{E}}} reduces the overall transconductance G m = g m {\displaystyle G_{m}=g_{m}} of the circuit by a factor of g m R E + 1 {\displaystyle g_{m}R_{\text{E}}+1} , which makes the voltage gain where g m R E ≫ 1 {\displaystyle g_{m}R_{\text{E}}\gg 1} . The voltage gain depends almost exclusively on

116-424: A 2SC2240 Toshiba transistor, which is only special insofar as it is cheap and reliable. The transistor boost stage consists of two highpass filters in series, followed by a Common emitter amplifier. This serves to remove unnecessary bass frequencies before the distortion stage, preventing the signal from accumulating muddiness as it is amplified. This stage provides a 35 dB boost to the signal, and introduces

145-460: A black body, released in 2017. DS-1W – WazaCraft version, released in 2023. DS-1-B50A – Orange metallic paint to commemorate the company's 50th anniversary; released in 2023 and limited to 7,000 units. The blueprint of the DS-1 circuit is simple, with a pair of in- and output buffers surrounding a transistor boost stage, an operational amplifier gain stage with hard clipping diodes , and

174-486: A letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=DS1&oldid=1212380028 " Category : Letter–number combination disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages BOSS DS-1 Boss released

203-408: A low forward voltage will make the pedal quieter but with a more saturated distortion, a diode with a high forward voltage will be louder but with less available distortion. Last but not least, the humble " big muff pi" style tone control immediately preceding the output buffer is a fixed cutoff lowpass filter and a fixed cuttoff highpass filter which attenuate either the low or high end, depending on

232-568: A small amount of distortion. The operational amplifier gain stage is the most important part of the Boss DS-1 circuit, featuring the clipping diodes , Op-amps and further filters which refine and color the sound. The op-amp stage is the only part of the circuit which has undergone any real changes over the pedals history. Originally, in 1978, the circuit was built around the Toshiba TA7136AP pre-amplifier, not an op-amp, and this gave

261-552: A successor, the DS-2. The DS-2, "Turbo Distortion" was released in 1987, and is very similar to the DS-1 except that it features a "turbo" setting, which produces a sharper midrange tone. Boss released a black limited edition 40th Anniversary model of the DS-1 in 2017. DS-1 – The original pedal, released in 1978. DS-1 BK – a Guitar Center exclusive with orange font on a black body, released in 2016 and limited to 3,000 units. DS-1-4A – A 40th-anniversary addition with gold font on

290-461: A survival horror game VR Class Ds1 , a Finnish railbus class DS-1 Orbital Battle Station, the full name of the original Death Star space station in the Star Wars franchise See also [ edit ] DS (disambiguation) Canon EOS-1Ds series [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as

319-494: A tone control. It features the same JFET switching circuit as some other Boss effects units, allowing a simple momentary push button to reroute the signal, either bypassing the effect or engaging it. In either state, the signal will pass through the input and output buffer stage of the effect, and this is the key differentiating factor between Boss pedals and "true bypass" pedals. The buffers themselves are similar, both Common collector amplifiers with unity gain. They each feature

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348-489: A very small change in base current produces a large change in collector current, the current gain (β) is always greater than unity for the common-emitter circuit, a typical value is about 50. A typical example of the use of a common-emitter amplifier is shown in Figure 3. The input capacitor C removes any DC component of the input, and the resistors R 1 and R 2 bias the transistor so that it will remain in active mode for

377-445: A voltage buffer like an emitter follower . Common-emitter amplifiers are also used in radio frequency circuits, for example to amplify faint signals received by an antenna . In this case it is common to replace the load resistor with a tuned circuit. This may be done to limit the bandwidth to a narrow band centered around the intended operating frequency. More importantly it also allows the circuit to operate at higher frequencies as

406-413: Is also named common-emitter amplifier because the emitter of the transistor is common to both the input circuit and output circuit. The input signal is applied across the ground and the base circuit of the transistor. The output signal appears across ground and the collector of the transistor. Since the emitter is connected to the ground, it is common to signals, input and output. The common-emitter circuit

435-417: Is negative) from the base to ground . This large capacitor greatly decreases the bandwidth of the amplifier as it makes the time constant of the parasitic input RC filter r s ( 1 − A V ) C CB {\displaystyle r_{\text{s}}(1-A_{\text{V}})C_{\text{CB}}\,} where r s {\displaystyle r_{\text{s}}\,}

464-559: Is reduced. The bandwidth of the common-emitter amplifier tends to be low due to high capacitance resulting from the Miller effect . The parasitic base-collector capacitance C CB {\displaystyle C_{\text{CB}}\,} appears like a larger parasitic capacitor C CB ( 1 − A v ) {\displaystyle C_{\text{CB}}(1-A_{\text{v}})\,} (where A v {\displaystyle A_{\text{v}}\,}

493-463: Is the output impedance of the signal source connected to the ideal base. The problem can be mitigated in several ways, including: The Miller effect negatively affects the performance of the common source amplifier in the same way (and has similar solutions). When an AC signal is applied to the transistor amplifier it causes the base voltage VB to fluctuate in value at the AC signal. The positive half of

522-426: Is the most widely used of junction transistor amplifiers. As compared with the common-base connection, it has higher input impedance and lower output impedance. A single power supply is easily used for biasing. In addition, higher voltage and power gains are usually obtained for common-emitter (CE) operation. Current gain in the common emitter circuit is obtained from the base and the collector circuit currents. Because

551-406: The amplifier an inverted output and can have a very high gain that may vary widely from one transistor to the next. The gain is a strong function of both temperature and bias current, and so the actual gain is somewhat unpredictable. Stability is another problem associated with such high-gain circuits due to any unintentional positive feedback that may be present. Other problems associated with

580-531: The applied signal will cause an increase in the value of VB this turn will increase the base current IB and cause a corresponding increase in emitter current IE and collector current IC. As a result, the collector emitter voltage will be reduced because of the increase voltage drop across RL. The negative alternation of an AC signal will cause a decrease in IB this action then causes a corresponding decrease in IE through RL. It

609-449: The centerpiece of the circuit to this day. Most of the distortion itself is handled by the silicon 1N4148 clipping diodes organized in a hard clipping arrangement, clipping any signal above 0.7v and below -0.7v. One of the popular modifications to the DS-1 consists of replacing one or both of the diodes, labeled D4 and D5, with LED or germanium diodes. Depending on the diodes, the pedal can take on many different sonic characters. A diode with

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638-407: The circuit are the low input dynamic range imposed by the small-signal limit; there is high distortion if this limit is exceeded and the transistor ceases to behave like its small-signal model. One common way of alleviating these issues is with emitter degeneration . This refers to the addition of a small resistor between the emitter and the common signal source (e.g., the ground reference or

667-583: The effect more of a warm, rich sound. In 1994, the Toshiba pre-amps were nearing the end of their stock life, and so the circuit had to be modified in order to play host to an easier to find dual op amp, the Rohm BA728N. This version is slightly quieter than the original, but is otherwise essentially the same. The Rohm op-amp was replaced in 2000 by the Mitsubishi M5223AL op-amp, which remains

696-403: The entire range of the input. The output is an inverted copy of the AC component of the input that has been amplified by the ratio R C / R E and shifted by an amount determined by all four resistors. Because R C is often large, the output impedance of this circuit can be prohibitively high. To alleviate this problem, R C is kept as low as possible and the amplifier is followed by

725-397: The expressions effectively simplify to the ones given by the rightmost column (note that the voltage gain is an ideal value; the actual gain is somewhat unpredictable). As expected, when R E {\displaystyle R_{\text{E}}\,} is increased, the input impedance is increased and the voltage gain A v {\displaystyle A_{\text{v}}\,}

754-409: The input. In this circuit, the base terminal of the transistor serves as the input, the collector is the output, and the emitter is common to both (for example, it may be tied to ground reference or a power supply rail ), hence its name. The analogous FET circuit is the common-source amplifier, and the analogous tube circuit is the common-cathode amplifier. Common-emitter amplifiers give

783-454: The invention of the negative feedback amplifier and does not reduce output impedance or increase bandwidth, as a true negative feedback amplifier would do. ) At low frequencies and using a simplified hybrid-pi model , the following small-signal characteristics can be derived. If the emitter degeneration resistor is not present, then R E = 0 Ω {\displaystyle R_{\text{E}}=0\,\Omega } , and

812-473: The position of the potentiometer . The way the two filters are interconnected creates a notch, or scoop, around 500 Hz when the potentiometer is in the center position. The seasaw nature of the tone control leads to a -12 dB volume loss which gives the pedal an output of 350mV , which is suitable for most applications but does create issues with the DS-1 being able to achieve unity gain with higher level inputs. Common emitter In electronics ,

841-468: The ratio of the resistors R C / R E {\displaystyle R_{\text{C}}/R_{\text{E}}} rather than the transistor's intrinsic and unpredictable characteristics. The distortion and stability characteristics of the circuit are thus improved at the expense of a reduction in gain. (While this is often described as " negative feedback ", as it reduces gain, raises input impedance, and reduces distortion, it predates

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