I have an Usher R1.5, from what I read, it is a close copy of Thresholds/Pass' Stasis S300 amp. The Usher is 50 watts Class A / 150 watts Class AB
To get 50 watts Class A, I would need to bump up the bias and ensure that the heatsinks are at 50c. When I got my amp, it was idling at 36c. My infrared thermometer's upper limit is 42c, so I biased the amp up to 42c. New infrared thermometer with 100c upper limit is on order. I am familiar with Nelson Pass' 10 second hand rule on measuring temp on the heat sink, but do not want to take a chance right now 🙂
Will there be a noticeable improvement in sound quality once I get to 50c?
What happens if a put two small fans on each side to cool the heatsink, aside from cooling the heatsinks, will it have a negative effect on sound quality?
To get 50 watts Class A, I would need to bump up the bias and ensure that the heatsinks are at 50c. When I got my amp, it was idling at 36c. My infrared thermometer's upper limit is 42c, so I biased the amp up to 42c. New infrared thermometer with 100c upper limit is on order. I am familiar with Nelson Pass' 10 second hand rule on measuring temp on the heat sink, but do not want to take a chance right now 🙂
Will there be a noticeable improvement in sound quality once I get to 50c?
What happens if a put two small fans on each side to cool the heatsink, aside from cooling the heatsinks, will it have a negative effect on sound quality?
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Fans are fine, and your electrolytic capacitors will thank you. Aside for the heat hazard,
heat sink temp implies the device junction temp, which is critical.
heat sink temp implies the device junction temp, which is critical.
