Pass "DeLite" Amp from BAF

Lesson in topography, you can't have it all!

I love my De-Lite so much I decided to fashion a proper chassis for it so that it may reside in the living room with the wifey, teenage girls, and the dogs. Many hours were spent as my carpentry is rusty at best. When I turned it on beautiful music sprang forth but there it was...Humm! A buzz I just can't ignore. And this buzz was not present in my first super sloppy build. I now get why so many go on about the importance of topography. Trying to cram these giant capacitors, a giant transformer, and mosfets that will amplify signal noise into this small of a space is just a disaster. There's no room for clean wiring the AC and DC are way too close together and it was such a struggle to tighten each screw. PITA!

So back to the drawing board with more space.

As a side note I also learned its best to read the description when buying parts. AC & DC panel voltmeters are not the same.

P.S. I don't have the heart to dismantle it just yet it's currently playing some very soothing Aimee Mann
 

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I love an amp with all the connectors on the front face. I don't understand why commercial amps have connectors on the back! :D

A quick shot of some of the back of my rack will tell you why :D

It's a Zen-Mod'ism which translates to words of high praise.

Great job!

:cheers:

Thanks! Ya I get it now :) I might turn the chassis black and leave the heatsink as it is. Then it'd be really fugly :D
 

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So the sockets arrive today and I'll be able to see how it works.

I am expecting hum since it's SE and unregulated, but I've added what I think will be a Hum adjustment. What do you think? I feel like it's a blend of Aikido and Janus. 1k might be off for the pot but I won't know until it's alive.

I also added a safety diode for the tube.
 

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For what it's worth the panel with the voltmeters and the connectors was intended to be the back panel. I put the meters in to be able to adjust the drain to ground voltage without having to connect a DMM. Where I live the temperature swings quite dramatically affecting the drain to ground voltage. I have found that Papa's suggestion of 25V is sonically on point. I tried many other voltages and none were better, some noticably worse.

Jeffrey
 
Hi Dennis,

Indeed Aimee Mann is for quiet amplifiers. The Magnolia Sountrack is one of my "test" records. On the first build of this amp I had the wifey sit and listen to it. Eyes closed nearfield listening and she said-without prompting: "Wow it's like she's in the room singing just for me."

Jeffrey
 
Ok. After realizing I was using different MOSFETs, I rigged up a bias control. I also ordered 500W light bulbs.

But I'm listening to feedback free single ended MOSFETs and I'm in disbelief that these are this linear without help!

Not sure how hot I want the heat sink to get but it's already in the 65c area...

What's going on here!

There's a 6 in 4 out speaker switch etc there :)
 

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