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Old 02-12-2018, 05:07 PM
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SwizzyMan SwizzyMan is offline
Restoring an admiral c322
 
Join Date: Apr 2015
Location: Side Lake Mn
Posts: 886
Well to start they are both totally different tubes. The as7 is a simple low mu twin triode while the 6L6 is a high mu and high power pentode capable of 30 watts of plate dissipation (on a single plate) while the as7 only dissipates a grand total of 26 watts (keep in mind 13 per plate). The as7 is a lower power tube and is not nearly as efficient when used as an audio amp tube. For example, running a 6AS7 in a class A1 amp only gives an amplification factor of 2 while a 6L6 in the same setup has an amp factor of 8. We must take into account that a single pentode 6l6 puts out more than double the amplification factor than using two triodes thus making the 6l6 a more efficient and powerful tube with out the manufacturing costs of two separate triodes in one tube. RCA intended for this tube to be used in lower power circuits and had high power audio triodes such as the 6sn7gtb's which at less plate and screen voltage have an amp factor of 20 in a class A1 amp which is perfect for audio use. The as7 was never really meant to be used for audio circuits, its main use was as a series regulator in scopes and other test equipment such as signal generators ans supplies. Nowadays the audio fools see a nice big twin triode and automatically assume it would be great for their amps, none really do their research and look to see if this tube is really ideal as an amp tube.
Just my 2 cents....or more
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Admiral C322C2 Regent (Restoring)
RCA CTC-7 Pensbury (Restored)
RCA CTC-5 Westcott (Restored)
CRA CTC--4 Director 21 (Restoring)
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