diode dampener bias comparo

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Recently, a comparison was made between a resistor and a diode dampener as a means of providing bias for an output tube. Here is how it was done with an accompanying description of the amplifier that served as the test bed for the comparison. First the description of the amplifier as the comparison began. It is a two stage amp stereo amp using the 5842 RC coupled to a 46 which is AC heated. A hum balance pot is used and the wiper connected to the cathode resistor and bypass cap. The cathodes of each respective stage are shared. The power supply consisted of two diode dampeners used for rectification and a pi filter. The amp was well known.
To convert to the biasing the output tubes with the diode dampeners the following was done. Two hexfreds replaced the diode dampeners serving as rectifiers. The cathode resistors and their bypass capacitors were removed. The wipers of each hum balance pot were connect to the diode dampeners that were then wired in series to ground. Bias and operating points were pretty close, though there was 20 volts of B+ increase.
The sound improved a bit with the diode dampener bias. Nothing huge though, just a bit more juicy. Not really sure one could tell much without the back to back comparison done in this fashion. However, the turn on was much improved. Total silence up to operation. Absolutely beautiful.

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Topic - diode dampener bias comparo - larry moore 06:22:17 10/31/01 (4)

Re: diode dampener bias comparo - hifitom 23:21:22 10/31/01 (1)

Re: diode dampener bias comparo - larry moore 05:41:36 11/01/01 (0)

Re: diode dampener bias comparo - Perseo 13:35:57 10/31/01 (1)

Re: diode dampener bias comparo - larry moore 05:38:53 11/01/01 (0)

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