New and Improved TCJ Stepped Attenuator Kit * Sold Out
Product Description
Why Use Stepped Attenuators
The stepped attenuator is an attempt to overcome the liabilities of the conventional potentiometer-based volume control. Even the best potentiometer compromises the quality of the signal that flows through it. The thin film of resistive paint and metal scraper that make up the average potentiometer seem to damage the signal almost as much as they attenuate it. Furthermore, finding a stereo potentiometer that follows a logarithmic taper and that can track from one channel to the other is tough. With the stepped attenuator, on the other hand, high-quality fixed resistors replace the carbon track and, likewise, high quality switch contacts replace the metal scraper. Because tight-tolerance resistors are readily available, there is no problem in following the logarithmic taper accurately and consistently.
The TCJ Stepped Attenuator
The TCJ attenuator is a high-end audio product. This hybrid design uses both series and ladder attenuators to yield the best compramise between flexibility, performance, and cost. The TCJ attenuator uses three hard-gold Elma rotary switches to yield a total of 66 positions of attenuation in -1dB decrements. The leftmost and rightmost switches hold just six positions and are mono attenuators for the left and right channels. These flanking switches are configured as ladder attenuators, with only two resistors switched in at a time, attenuating up to -5dB per channel. The center switch cascades from the two flanking switches and it defines a stereo series attenuator with 11 resistors in series per channel, with -6dB decrements, establishing a maximum of -60dB of attenuation. Adding the ladder and series stepped attenuators&' attenuation together gives a maximum attenuation of -65dB.
PCBs are 1.4 inches tall and 9 inches long and will fit within a 1U rack-mount enclosure. Each resistor position holds a redundant set of pads, so that radial and axial resistors can be used.
The attenuator holds its own balance control of sorts. The center knob controls the volume for both channels, and offers 11 coarse -6dB decrements; the flanking knobs offer six fine -1dB decrements for each channel, creating a volume control and balance control in one easy-to-use stepped attenuator. In other words, all three switches should be used to set the desired sound level. Far too many imagine that the flanking ladder stepped attenuators are only to be used when the source material is out of balance. Wrong.
Perfect for passive and active line stages.
The kit includes instructions and three high-quality, Swiss-made, gold-heavy, precisely-designed and exquisitely-made, Elma rotary switches and one USA-made extra-thick, high-quality PCB, with 2oz copper and solder mask and silkscreen.
The kits are sold without resistors, so you, the purchaser, can use your favorite. But packs of all the needed resistors are also for sale ($10 USD), in both metal-film and carbon-film.
The stepped attenuator is an attempt to overcome the liabilities of the conventional potentiometer-based volume control. Even the best potentiometer compromises the quality of the signal that flows through it. The thin film of resistive paint and metal scraper that make up the average potentiometer seem to damage the signal almost as much as they attenuate it. Furthermore, finding a stereo potentiometer that follows a logarithmic taper and that can track from one channel to the other is tough. With the stepped attenuator, on the other hand, high-quality fixed resistors replace the carbon track and, likewise, high quality switch contacts replace the metal scraper. Because tight-tolerance resistors are readily available, there is no problem in following the logarithmic taper accurately and consistently.
The TCJ Stepped Attenuator
The TCJ attenuator is a high-end audio product. This hybrid design uses both series and ladder attenuators to yield the best compramise between flexibility, performance, and cost. The TCJ attenuator uses three hard-gold Elma rotary switches to yield a total of 66 positions of attenuation in -1dB decrements. The leftmost and rightmost switches hold just six positions and are mono attenuators for the left and right channels. These flanking switches are configured as ladder attenuators, with only two resistors switched in at a time, attenuating up to -5dB per channel. The center switch cascades from the two flanking switches and it defines a stereo series attenuator with 11 resistors in series per channel, with -6dB decrements, establishing a maximum of -60dB of attenuation. Adding the ladder and series stepped attenuators&' attenuation together gives a maximum attenuation of -65dB.
PCBs are 1.4 inches tall and 9 inches long and will fit within a 1U rack-mount enclosure. Each resistor position holds a redundant set of pads, so that radial and axial resistors can be used.
The attenuator holds its own balance control of sorts. The center knob controls the volume for both channels, and offers 11 coarse -6dB decrements; the flanking knobs offer six fine -1dB decrements for each channel, creating a volume control and balance control in one easy-to-use stepped attenuator. In other words, all three switches should be used to set the desired sound level. Far too many imagine that the flanking ladder stepped attenuators are only to be used when the source material is out of balance. Wrong.
Perfect for passive and active line stages.
The kit includes instructions and three high-quality, Swiss-made, gold-heavy, precisely-designed and exquisitely-made, Elma rotary switches and one USA-made extra-thick, high-quality PCB, with 2oz copper and solder mask and silkscreen.
The kits are sold without resistors, so you, the purchaser, can use your favorite. But packs of all the needed resistors are also for sale ($10 USD), in both metal-film and carbon-film.
