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Bottlehead Kits => Legacy Kit Products => Crack-a-two-a => Topic started by: XforceVesa2 on November 24, 2019, 07:59:33 PM

Title: Plate Vibration if Amp is On
Post by: XforceVesa2 on November 24, 2019, 07:59:33 PM
Hello Community,

I've just completed my Crackatwoa Build and everything seems to work fine.

The only strange thing i've discovered is that the plate of the Amp seems like to Vibrate when I turn the Amp On(It vibrate only slight and I notice it only if I touch the Plate of the Amp).

The Resistance and Voltage Check showed no Problems.

I hope you can help me with that Question.


Thanks in advance

Vesa
Title: Re: Plate Vibration if Amp is On
Post by: Paul Birkeland on November 25, 2019, 04:34:58 AM
I would try tightening down on the transformer screws. 

It would also be helpful to review your incoming AC voltage and what you wired the transformer for.  If you apply too much primary voltage, that could also cause some issues.
Title: Re: Plate Vibration if Amp is On
Post by: XforceVesa2 on November 25, 2019, 10:16:08 AM
At the Time of Building my Incoming Voltage was 235VAC, so I've wired my Transformer as stated in the Manual as "Greater than 225 VAC , less than 235 VAC".

The vibrations seems really come from the Transformer, if I go near the transformer I can hear a 50 Hz hum.

Edit: I've tighten the screw from the Transformer and the vibrations seems to be gone but I can still hear a slight 50 Hz Hum from the transformer(But I think thats a normal phenomen)
Title: Re: Plate Vibration if Amp is On
Post by: Doc B. on November 25, 2019, 10:56:12 AM
If you are hearing a slight hum when your ear is within about 30-40cm of the transformer that is normal.
Title: Re: Plate Vibration if Amp is On
Post by: XforceVesa2 on November 25, 2019, 10:53:07 PM
The Vibration seems to be back....


Im not sure if this is a problem of that i should be concerned since it doesn't seems to impact the Sound performance of this Amp?
Title: Re: Plate Vibration if Amp is On
Post by: Paul Birkeland on November 26, 2019, 05:15:21 AM
If it's intermittent, it could also be an issue on the powerline.  Is there any other appliance that has been on both times?  Certain devices can leave some DC on your mains and cause some issues like this.
Title: Re: Plate Vibration if Amp is On
Post by: XforceVesa2 on November 26, 2019, 10:51:32 PM
It seems like that it's there the whole time, if I push the Plate with my hand down on the edges(the plate is slightly bend), then the vibration disappear.


Edit: Apart from the slight Vibration I can't detect another Problem. Im just not sure if this could indicate a serious Problem with my Amp.
Title: Re: Plate Vibration if Amp is On
Post by: Deke609 on November 27, 2019, 03:48:28 AM
if I push the Plate with my hand down on the edges(the plate is slightly bend), then the vibration disappear.

If the chassis plate is bent, maybe adding some silicone dots (the kind used for cabinet doors) to the corners might help?  You could place them right on the underside corner points and trim the excess. It's a cheap experiment - so might be worth a shot.

cheers, Derek
Title: Re: Plate Vibration if Amp is On
Post by: Paul Birkeland on November 27, 2019, 04:39:24 AM
It's unlikely to be a serious problem.  When a serious problem causes transformer noise, that also comes with DC voltages that won't look right. 

You could tighten the hardware down just a little bit more to see if that helps.

-PB