How long did it take to complete your first GC?

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Well, I wouldn't call it "complete", but it's close, and it only took 3 years, and that doesn't include the time researching and ordering parts. So here it is: a basic LM3875 inverted GC, ala Nuuk. With exception of two Black Gate Caps and a couple of resistors, all the parts, including the case materials, are from the local surplus shops. For the time being, I'm just running it in my shop off a cheap CDP with a passive vol. and cheap speakers, but I'm really impressed so far. Dead quiet and <20mV DC output. In hindsight, I wish I had sourced the components a little more carefully. Maybe I'll rebuild it with quality components.

Here's the first channel in May 04:
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And the second channel was added in Aug 04:
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I spent some time listening in my shop with a portable CD player and realized this had some real potential. It took a couple years popping into the machine shop on lunch breaks to put together a case:
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And here is the result with the passive pre:
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Is it complete...well, not really. I 'd still like to remove the dykem, buff the scratches out of the aluminum, build a new bottom since it's a little like swiss cheese after moving parts around and counter-bore the SHCS on the face plate. I guess that's next years project.

Dave

PS Thanks for the help of the board members along the way.
 
Nordic said:
Looks very nice!

Those exposed fuses bother me though, can't say I've never been shocked by them.

Nordic-
The primary AC fuse is mounted in an enclosed holder just above the IEC power socket, the exposed fuses are on the low voltage DC legs. I plan on removing the low voltage fuses once I'm sure everything is working properly, but I don't think they pose any danger.

Thanks for looking,
Dave
 
Re: I likey!

lgreen said:
A lot of my projects take multiple years to make. But the truth is you are never quite done, are you?

And there are two categories of these: 1) the ones I keep tweaking, and 2) the ones my wife reminds me about that really are NOT finished.


markiemrboo said:
I like the case! Did you build this yourself too?

Thanks. Yep. the case is actually what took so long. I sneaked into the machine shop on lunch breaks when I could afford the time. It's pretty much a copy of the work others have done and posted on the galleries.

Dave
 
case time

Great looking project! I completely understand about the swiss cheese bottom.
I'll bet for something like a GC the case will always take you far longer to complete than the circuit layout. I used an old computer case (IBM PCjr) and it took me a couple hours every night after work for exactly a week to get everything right. ( I kept changing the internal layout around also) I'm still working on it as I just got the parts to build the AD815 based pre and it also will be housed in the case.
 
My 1st GC, in 2005, using a PCB a friend made, took a saturday afternoon to complete. (including modifying the chassis, buying the chassis, the resistor, sockets, plugs, capacitors, and transformer)

cheers
 

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Hi Hewie,

I'm the impatient type....:blush: My philosophy "A lousy singing amp is better then any silent amp":smash:

Glad that you like the box, it was originally a tissue box, I replace the bottom ply with an 5mm thk aluminum plate (with some holes drilled) for better mechanical strength and double as the heatsink...

It was a LM1875, since the chip has very good PSRR, the power supply section was a breeze...

Cheers
 
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