Almost finished, but a couple questions.

Sp33ls · 2417

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Offline Paul Birkeland

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Reply #15 on: April 20, 2018, 11:53:48 AM
The output transformers are on the bottom side of the chassis with solder terminals and the plate chokes are up top with the blue, red, and black wires coming out. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline fullheadofnothing

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Reply #16 on: April 20, 2018, 11:55:29 AM
The output transformer is the one with sticker that says "OT-5."

Joshua Harris

I Write the Manuals That Make The Whole World Sing
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Offline Sp33ls

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Reply #17 on: April 22, 2018, 05:39:23 PM
So, I installed the DC filament kit. Voltages checked out okay afterwards. 0.0mVAC background from the posts. For some reason, I could only get the noise down to 8mVAC each channel prior to the kit.

I was wondering if experiencing "pops" and "crackles" from the speakers when turning the Kaiju on/off is normal? 

I cranked the transformers down, but still getting the buzz noise from the amp   :-\



Offline Paul Birkeland

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Reply #18 on: April 22, 2018, 06:07:02 PM
Yes, there's a little bit of noise when you turn the amp on and off.

Depending on your meter, it may not resolve low AC voltages all that well. 

Another possibility for a buzzing transformer is DC pollution on the powerline.  Do you have any big motors running in the house?  Some dimmers can also pollute the line badly enough to disturb a power transformer.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Sp33ls

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Reply #19 on: April 22, 2018, 06:45:29 PM
I use a Fluke 117, so it should be pretty solid.

I tested my the outlet next to where the Kaiju is plugged in... the DC voltage fluctates between about 0.014 to 0.021VDC. Would this be high for the transformer?



Offline Paul Birkeland

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Reply #20 on: April 23, 2018, 04:21:10 AM
The easiest way to know would be to just pop it into your car and plug it in at your workplace to listen to PT noise.


Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Sp33ls

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Reply #21 on: April 23, 2018, 06:42:46 AM
Still noisy outside the apartment :/ But, I just thought of something...

The manual points out that you should scrape away paint around the screw holes of certain areas. I scraped away the paint from just about everything on the chassis. But, I did not do that for the end bell.

I figured the end bell was just a protective / decorative piece and didn't need to really be grounded at all.

Do you think this could be a problem?

Thanks again.



Offline Paul Joppa

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Reply #22 on: April 23, 2018, 07:14:13 AM
It's a safety problem, at least. And a potential hum problem, though unlikely to be a cause of the mechanical hum you are observing.

Paul Joppa


Offline Sp33ls

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Reply #23 on: April 23, 2018, 07:33:20 AM
Okay. That being said, I did not paint the underside of the bell. When I get back from traveling for work next week, I can try scraping away the paint around the screws on the end bell and see if that makes a difference. Hopefully that'll do it.

How often do noisy transformers pop up for folks?
« Last Edit: April 23, 2018, 07:36:51 AM by Sp33ls »