01-11-2016, 06:03 PM
(This post was last modified: 01-11-2016, 06:04 PM by Murphyv310.)
Hi.
Personally I think the circuit is flawed.
The Triode stage should be a Voltage amplifier but the values you are using is hardly conducive to that.
The 12k anode load should be 10 or more times higher than that between 100k and 330k. The Volume control should be 470k to 1m and the cathode between 1.5k-3.3k, the ECC82 should really be an ECC83.
I suspect you have insufficient drive with the values you have and the drive is distorted and low.
The output stage looks OK although there is no need for the 100 ohm on the G2, the 2.2k is quite sufficient. Some NFB from the output transformer secondary to the cathode of the triode via a suitable RC network would be beneficial.
The Mullard 3-3 can use a higher HT as the cathode resistor is high so the V a-k is in respect not 300v. The big advantage in the 3-3 is it's directly coupled so eliminating phase errors.
Personally I think the circuit is flawed.
The Triode stage should be a Voltage amplifier but the values you are using is hardly conducive to that.
The 12k anode load should be 10 or more times higher than that between 100k and 330k. The Volume control should be 470k to 1m and the cathode between 1.5k-3.3k, the ECC82 should really be an ECC83.
I suspect you have insufficient drive with the values you have and the drive is distorted and low.
The output stage looks OK although there is no need for the 100 ohm on the G2, the 2.2k is quite sufficient. Some NFB from the output transformer secondary to the cathode of the triode via a suitable RC network would be beneficial.
The Mullard 3-3 can use a higher HT as the cathode resistor is high so the V a-k is in respect not 300v. The big advantage in the 3-3 is it's directly coupled so eliminating phase errors.
