15
TD-000436 -01 -A
Heat Loss Charts
Heat losses are the thermal emissions from an amplifi er 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 fi gures. 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
DPA4.2Q
180
46
DPA4.3Q 225
57
DPA4.5Q
286
72
Load per Channel
8
Ω
4
Ω
2
Ω
25V-70V-100V
BTU/hr
kcal/hr
BTU/hr
kcal/hr
BTU/hr
kcal/hr
BTU/hr
kcal/hr
1/8th Power
DPA4.2Q
432
109
476
120
597
150
nr
nr
DPA4.3Q 684
172
794
200
1040
262
nr
nr
DPA4.5Q
811
204
1144
288
1124
283
nr
nr
1/3rd Power
DPA4.2Q
849
214
873
220
1215
306
nr
nr
DPA4.3Q 983
248
1261
318
1869
471
nr
nr
DPA4.5Q
881
222
1708
430
1737
438
nr
nr
Full Power
DPA4.2Q
1352
341
1478
372
2120
534
nr
nr
DPA4.3Q 2498
629
2925
737
4198
1058
nr
nr
DPA4.5Q
3116
785
5318
1340
4208
1060
nr
nr
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
amplifi er's typical "clean" maximum level, without audible clipping. Use these fi gures 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.
