QSC Audio CXD4.3, CXD4.2, CXD4.5 manual Heat Loss Charts, Idle, Full Power

Heat Loss Charts

Heat losses are the thermal emissions from an amplifier while it is operating. It comes from dissipated waste power—i.e., real AC power in minus audio power out. Measurements are provided for various loads at idle, 1/8 of average full power, 1/3 of average full power, and full power, with all channels driven simultaneously. For typical usage, use the idle and 1/8 power figures. This data is measured from representative samples; due to production tolerances, actual heat emissions may vary slightly from one unit to another. Bridged mono into 8 ohms is equivalent to 4 ohms per channel; into 4 ohms is equivalent to 2 ohms per channel.

	BTU/hr	kcal/hr
Idle
CXD 4.3	225	57
CXD 4.5	286	72
Load per Channel	8Ω			4Ω		2Ω	25V-70V-100V
	BTU/hr	kcal/hr	BTU/hr	kcal/hr	BTU/hr	kcal/hr	BTU/hr	kcal/hr
1/8th Power
CXD 4.3	684	172	794	200	1040	262	794	200
CXD 4.5	811	204	1144	288	1124	283	1144	288
1/3rd Power
CXD 4.3	983	248	1261	318	1869	471	1261	318
CXD 4.5	881	222	1708	430	1737	438	1708	430
Full Power
CXD 4.3	2498	629	2925	737	4198	1058	2925	737
CXD 4.5	3116	785	5318	1340	4208	1060	5318	1340

EN

Idle

Thermal loss at idle or with very low signal level.

1/8 Power

Thermal loss at 1/8 of full power is measured with pink noise. It approximates operating with music or voice with light clipping and represents the amplifier's typical "clean" maximum level, without audible clipping. Use these figures for typical maximum level operation.

1/3 Power

Thermal loss at 1/3 of full power is measured with pink noise. It approximates operating with music or voice with very heavy clipping and a very compressed dynamic range.

Full Power

Thermal loss at full power is measured with a 1 kHz sine wave. However, it does not represent any real-world operating condition.

29 TD-000367-00-A