Relay Automation
The use of latched relays :
The use of latched relays :
Compared to potentiometer, latched relays have the following advantage and disadvantages:
- Relays should affects the signal less than a potentiometer (In theory it's even better than a "DACT" type attenuator because it has less cross-talk not being such a miniature.)
- For every step of the variable we are changing (for example frequency or volume) is known exactly the amount (for example what frequency is the cutoff or how many db you are attenuating the volume).
- The 2 channels (left and right) are always as matched as (tolerance in % / the number of resistors connected in parallel at the same time. [1 to 8]). Resistors are usually 1% tolerance while potentiometers are usually 20% tolerance.
- Relays and resistors networks usually show less inductance than a potentiometer.
- Well implemented, good quality relays last almost for ever. They are usually estimated to last hundreds of thousands of cycles.
- Good small signal relays ensure a pretty qualitative audio contact using precious metals like silver, palladium, gold and they are sealed, so no dust or humidity can degrade the component or their work.
- Latched relays not needs energy to keep their state. This is the same as a potentiometer. This component being passive .
- Relays can be more economical compared to expensive high quality potentiometers.
- a disadvantage is off course they are not continuous.
- an other disadvantage is also that they can click a bit in the audio and they produce a listenable physical click when they switch.