Aric Audio Systems Unlimited Preamp

Initial testing of The Motherlode preamplifier is complete! This unit was designed to fill the niche left by "The Dude" (which was a high end 6SN7 based preamp using all film capacitors and tube regulation in the power supply). This is a "no hold barred" design that was spawned between A'goner laaudionut and myself over the course of the last couple of months. He originally wanted to purchase a "Dude" only to find the owner/designer had regretfully passed away and the use market was becoming scarce for this gem. Flash forward to today, and I believe I have a unit that will compete on all levels AND includes a full tube phono stage as well. This is on my own personal "Got to have it" list as of today!

The magic of the Dude is in several design areas that make it unique. The 3 tube regulated power supply is a gem and to this day nobody has figured out how Paul the designer did it. Paul was an absolutely brilliant designer and while some aspects of his Dude preamp can be “copied” this is one that has not to date.

The way he used the 6sn7 tube is also unique and unconventional. He did not follow the established designs and conventional wisdom in books etc... He utilized the tube in unique ways that many would quickly dismiss as “wrong”. This is also unique to the Dude to date. 

Things like a robust Pi filter, circuit breaker instead of fuse, SS rectification, hand build Shallco silver contact stepped attenuator, and Duelund output caps can be matched.

We miss Paul and TRL gear. I like the fact that we are respecting his work by mentioning the Dude in this thread.

@grannyring much respect to "The Dude" and thank you for the insight on it’s uniqueness! In terms of similarities the ML has the breaker power switch, an exclusively film capacitor power supply and robust storage + PI filter stages. I’ve also employed SS rectification using dual series UF diodes per leg with snubbers across them in a full wave bridge, and perhaps a difference (not knowing the Dude architecture myself), is a large 5H choke after the first filter cap stage for smoothing. This uses a more conventional Mu-Follower stage with a 6SL7 as the amplification. TKD volume potentiometers, and Duelunds on the outputs (Jupiter PIO’s are used in the phono stage section). It’s fairly straightforward but does use a pair of OC3 regulators snubbed with small film capacitors to drop the excessive voltage at the tail end of the B+ before it hits the plate resistors. While there are many differences I’m sure, and this is not out to "clone" the design, I would more respectfully say this pays homage to The Dude in it’s basic structure. Best regards, Aric

Goodness I love what you are doing here. It will sound absolutely wonderful I am sure.  Very nice.  Love to see pictures if possible. 

Based on the pics of the Motherlode I've seen its a beauty. I don't know enough about the workings of all those impressive looking capacitors and such inside of the units to really appreciate what Aric has created here, but if it sounds better than the linestage he built for me ( and I'm sure it does ) this will be one sweet preamp. Can't wait to hear laaudionut's impressions of it.