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Wardsweb Gainclone amp update

Wardsweb

Wardsweb

Behind The Curtain
Staff member
Admin
Well the WWGC-1 has been on the shelf for over a year, so I decided to work on it today. For those who don't remember a very long time ago, I'm using sample LM3875TF chips from National Semiconductor, 6061 billet aluminum plate, 1" plexiglass, Parts Express transformer, heat sinks off Ebay and misc other parts I had laying around. It's all built now, just need to heat up the soldering iron and wire it. I take it to the Klipsch Meet in Austin this coming weekend.
 

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That IS cool! Love the plexiglass! How'd you do the "brushed" look? Just sandpaper? It is very even looking, nice! You'd never get clear plexi to stay looking good, so what you have done is excellent. Any plans for lighting inside? Nice cool glow of blue LED's?
 
Nice work, as always! :thmbsp:

Those heat sinks look totally overkill for the job! Please let us know if it even gets warm! Totally cool! :yes:
 
Wired with silver over copper teflon.

wiredfront_800.jpg
 
Damn even your plain Jane jobbers look nicer then anything I could ever kick out ! :)

Hows she sound ?
 
Negotiableterms said:
Done??? Whatya mean "done"???? Does it work? What does it sound like??? It looks awesome, but that's all we get? "Done"? :nono:
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I agree, what's the bottom line on this thing. Send it to EW for a clipping and distortion checkout. 50+ WPC is nothing to sneeze at, could be a really nice addition to anyones collection.

Lefty
 
Ok, I just spent the last hour and a half doing some critical listening. I threw everything from Amadeus Mozart Requiem to Evanescence Everyboy's Fool at it and it didn't even get warm. Jamie Cullum with spooky good imaging to Lindsey Buckingham's acoustic jammin Big Love, this thing is pure sweet. For a little piss ant amp, I'm impressed. I stated with some book shelf speakers and quickly moved to some floor standing JBLs so I could crank the living daylights out of it. Again call me impressed. Now with a better pre and source, can it get better? I'm taking it to the Klipsch meet in Austin next Saturday and see what they think of it pushing some LaSallas or K-Horns. :thmbsp:
 
That's more like it!!! Great job Luther! Now... when do you go into mass production, so we can all buy one?
 
Negotiableterms said:
That's more like it!!! Great job Luther! Now... when do you go into mass production, so we can all buy one?
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Well here is the run down.

a. Pcb's came from BrianGT on diyaudio.com, also found on his sites chipamp.com and briangt.com. Then there is Peter Daniel's site audiosector.com too.
b. LM3875 chip I had sampled from National Semiconductor.
c. transformer, caps and resistors from Parts Express
d. heat sinks, plexiglass and RCA jacks from Ebay
e. 6061 billet aluminum plate from a local metal supplier
f. IEC and binding posts from my scrap parts box
g. chrome ball feet (not visible in the picture) Home Depot
 
Are the small filter caps (1500 uf) on the boards enough? Any sign of hum? Do you think you would gain anything with 3300 uf or 4700 uf?

What is the volt/amp rating of the transformer?

Did you try it with 4 ohm loads? How did it react?

Great project!
 
Paul C said:
Are the small filter caps (1500 uf) on the boards enough? Any sign of hum? Do you think you would gain anything with 3300 uf or 4700 uf?
What is the volt/amp rating of the transformer?
Did you try it with 4 ohm loads? How did it react?
Great project!
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The amp is dead quiet, so I see no need to rethink the design.
The transformer is 250VA and dual 18V out. This regulates to about 26VDC.
Haven't tried 4 ohms yet, but should be fine with the 250VA.
 
This should answer many of the questions I've been getting:
parts list
a. Pcb's came from BrianGT on diyaudio.com, also found on his sites http://www.chipamp.com and http://www.briangt.com. Then there is Peter Daniel's site http://www.audiosector.com too.

b. LM3875 chip I had sampled from National Semiconductor .

c. transformer, caps and resistors from Parts Express.com

d. heat sinks, plexiglass and RCA jacks from Ebay

e. 6061 billet aluminum plate from a local metal supplier

f. IEC and binding posts from my scrap parts box

g. chrome ball feet (not visible in the picture) Home Depot

h. SWAG at investment $150
 
Nicely done. I love the use of the aluminum plate, looks like that would be reasonably easy to make on a manual mill :thmbsp:
 
Here it is driving some Klipsch Khorns. It really sounded great, but then it might have been the $100 power cord and $1000 power conditioner. :yes: :no: :scratch2:

Dsc_0173.jpg
 
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