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Hoffman Amps Forum image Author Topic: Issue with amp build  (Read 2869 times)

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Offline gerry113377

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Issue with amp build
« on: April 18, 2021, 04:24:45 pm »
{continued from here}

Hi,

I built my first tube amp. A KLD DC30 clone. It works on channel 2 but channel 1 makes a humming sound. I double checked everything, I also, removed everything and rewired it all. Still get the same humming. I disconnected channel 1 from the effects loop and the humming went away and then only had channel 2. Here is a youtube video of the humming, all schematics and a pic. If you need any more pics of a certain area let me know. Thanks.

 Gerry



« Last Edit: April 18, 2021, 10:19:40 pm by PRR »

Offline shooter

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Re: Issue with amp build
« Reply #1 on: April 18, 2021, 04:41:33 pm »
Quote
I disconnected channel 1 from the effects loop and the humming went away
did you jack IN some audio at CH1FX to see if it works downstream?
Went Class C for efficiency

Offline Latole

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Re: Issue with amp build
« Reply #2 on: April 18, 2021, 05:22:54 pm »
Seeing these long unshielded wires, I'm amazed that the amp is silent on channel 2.

Offline gerry113377

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Re: Issue with amp build
« Reply #3 on: April 18, 2021, 06:12:10 pm »
I am 100% sure the unshielded wires are not the cause of this problem.

Offline sluckey

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Re: Issue with amp build
« Reply #4 on: April 18, 2021, 06:50:19 pm »
Have you reviewed your thread from last year about this same problem?
A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline gerry113377

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Re: Issue with amp build
« Reply #5 on: April 18, 2021, 07:16:56 pm »
Sorry yeah, had a bunch of other projects so it's  been over a year, I decided to rewire the whole thing. Same problem, if you want  delete this and post I'll post there again, I wasn't sure to post there after a year. Guide me yoda. The old build had shieldef wire, I just ordered rg174.

Offline PRR

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Re: Issue with amp build
« Reply #6 on: April 18, 2021, 10:20:15 pm »
Let's just drop a link to last year's progress:
https://el34world.com/Forum/index.php?topic=25582.0

Offline gerry113377

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Re: Issue with amp build
« Reply #7 on: April 19, 2021, 05:58:17 am »
Anyway, I should have never picked such a difficult amp kit in the first place from an unknown company. My bad for even asking and wasting every one's time. Moderator just please delete both these posts.

 


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