Tekton Double Impacts

Thanks for the kudos Tom- I'm glad you're enjoying the 300B! Just a note for anyone curious for more detail regarding the amplifier. It uses a single 6SN7, that uses one triode of the tube for the input signal gain, and the second as the driver for the 300B. Each stage has a defeatable cathode bypass capacitor, which boosts the current coming from the stage. Up, or "On" enables the cathode capacitor, and Down removes it (allowing a current-dependent "feedback" and lowering the gain of that stage). With both of them up, the gain architecture of both stages is quite high- and as such is susceptible to noise (especially with the gain control of the amp at full tilt- or close). These can be adjusted depending on the preamplifier's gain used, and allow you to "tailor" the gain architecture of the amp. It can also be used as an integrated with both bypass switches set to UP- and driven directly from a source (DAC, CD player, etc.). 

Regarding the "cheater plug" suggestion, it was suggested as a test to determine whether a ground loop may have been present or not. All audio gear has some sort of signal ground reference to circuit ground- some are isolated and some are not. I isolate the chassis from ground via an RC circuit, however another component may try to find "ground" through the signal. Sometimes moving a component to a different AC circuit, or lifting a ground somewhere in the signal path can eliminate AC-induced ground noise. 

Best wishes, Aric

Aric,
Just how "hefty" is the amp.....what is the weight and dimensions?

Lula,

The chassis is 18.5" wide X 13.5" deep x 3.5" tall, with the power transformer sitting about 4.5" above that (with the tops of the 300B’s extending above those about an inch). Weight is just under 55 lbs unboxed- closer to 60 lbs packed. The amplifier uses two 5U4 rectifier tubes and independent transformers for each circuit in the unit. Best, Aric

Aric,
Your description of the cathode capacitors explains the seeming high gain Tom has. Good to know that the gain level is adjustable.  This sure seems to be a very well engineered amplifier and exceptionally good sounding based on Tom's sheer joy😊.

Tom, Just let me know when you're ready for me to come over again. Im really looking forward to it. 
Charles 

Tom (Mac48025), my congratulations as well for this excellent improvement to an already very fine system. And kudos to Aric for making it possible.

Regarding the hum/buzz issue, I don’t know how you have the components physically arranged, but if your MZ2 is in close proximity to the amp or to any of your other components, including its own external power supply, you might try repositioning it to increase the distance between it and everything else in the system.

I particularly suggest that because in looking at photos of the MZ2’s innards it appears that its output signal grounds are directly connected to its chassis. Which I’m thinking might result in a small hum/buzz voltage being applied to the input ground of Aric’s amplifier corresponding to whatever small AC-related voltage may be magnetically induced onto the MZ2’s chassis by a nearby component.

As you are probably aware, use of a cheater plug as a long term solution results in a small but non-zero safety risk. (Note Aric’s statement above that the cheater plug was suggested "as a test").

In any event, congratulations once again!

Best regards,
-- Al