LOAD CARRYIXG CAPACITY OF AM PI J TIERS 



587 



In selecting from these results some i)oint to be taken as the maxi- 

 mum carrying cai)acity of this amplifier, the question arises as to how 

 much the second harmonic which is present at practically all loads 

 will be noticeable. This, of course, depends on the training of the 

 ear of the obserxer and on the cjuality of the music being transmitted. 

 Comparing the note obtained from a cone type loud speaker when the 

 wave corresponding to an output of .043 watts was applied with 



.34 WATTS 



44 VVATTS 



.54 WATTS 



.65 WATTS 



.615 WATTS 



Input X'oltage 



Fig. 14— Amplifier No. 3; 1,000 c.p.s.; load 600 ohm resistance 



that obtained when the 1,000 cycle input was applied so as to pro- 

 duce a note of equal volume, it was found that it required a fairly 

 sensitive ear to note the change in quality. On the other hand when 

 a wave corresponding to the output wave obtained at a level of .068 

 watt was used for comparison the difference in quality between the 

 pure tone and the distorted output was very easily noticed. From 

 these data it may be assumed that when this amplifier is used in a 

 system for the transmission and reproduction of speech or music it 



