Hi Guys,
I recently completed a dual mono Aikido line preamp build using all 6CG7 tubes and dual Janus shunt regulator PSUs and used an A3 mini as an attenuator. The A3 is using 1% metal film resistors kit, 20K with 1.5 dB resolution. The pre is driving a 150 wpc SKA dual mono SS amp. The A3 appears to be working correctly in that the center switch controls the coarse attenuation for both channels and the switches on either side control the finer attenuation for each channel. The fine adjustments are fine, my problem is that even at the lowest coarse attenuator setting things are too loud for comfortable listening. I’m doubting that the 2 dB resolution resistors shown in the table in the user guide will provide enough attenuation. What I need is coarse adjustment that is significantly greater than I have now. I do like the ability to do some channel balancing with attenuator design and would like to try and keep it. Can you help point me in the right direction to calculate some more suitable values for the coarse adjustment.
By the way I think that the dual mono version sounds significantly better than the 9 pin all in one that I also built.
Thanks,
PJN
I recently completed a dual mono Aikido line preamp build using all 6CG7 tubes and dual Janus shunt regulator PSUs and used an A3 mini as an attenuator. The A3 is using 1% metal film resistors kit, 20K with 1.5 dB resolution. The pre is driving a 150 wpc SKA dual mono SS amp. The A3 appears to be working correctly in that the center switch controls the coarse attenuation for both channels and the switches on either side control the finer attenuation for each channel. The fine adjustments are fine, my problem is that even at the lowest coarse attenuator setting things are too loud for comfortable listening. I’m doubting that the 2 dB resolution resistors shown in the table in the user guide will provide enough attenuation. What I need is coarse adjustment that is significantly greater than I have now. I do like the ability to do some channel balancing with attenuator design and would like to try and keep it. Can you help point me in the right direction to calculate some more suitable values for the coarse adjustment.
By the way I think that the dual mono version sounds significantly better than the 9 pin all in one that I also built.
Thanks,
PJN