While proper biasing at 1.2A for 8 ohm speakers is important for good performance, it can also lead to heat generation in JLH amplifiers, especially if using horizontal heat sinks. This might cause some to run a cooler amplifier by under-biasing it, but that can negatively impact sound quality and stability.
Horizontal heat sinks: These can be less effective at dissipating heat compared to vertical heat sinks due to reduced airflow.
Proper bias current: 1.2A for 8 ohm speakers is a recommended bias current for JLH amplifiers for optimal performance.
Heat generation: JLH amplifiers can get hot, especially with horizontal heat sinks and proper bias current.
Under-biasing: Running a JLH amplifier with lower than recommended bias current may lead to cooler operation but can also cause distortion and instability.