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I have run into some noise issues when i activate the VRM by rotating the pot that activates the mosfet. I can play out of any of the four inputs of both channels while VRM is not activated, and the amp sounds incredible! Can anyone tell me if this noise would go away if i relocated the 1 M resistors from the inputs to the tube pin / ground? What would happen if i left the 1 M resistors on the inputs, and added two additional 1M resistors at the tube pin/ground? I have already added the capacitors at the tube pins but i know it stated to change the the 1 M resistor location if necessary. I would appreciate any feedback on how to solve this noise issue as is the VRM is not useable until i can fix this final issue.

Cheers

There should be no problems if you followed the layout and move the 68K as well.
But, with the VRM in place, does the voltage vary as you turn the dial? i.e. basic funcstionality? The rest is lead dress.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

It does have its functionality, both the voltage and the volume decrease as the pot is turned. The only part of the layout I did not follow is moving the 1 M resistors from the inputs to the tube pins. I do not get any noise whatsoever when the VRM is not engaged. Do you think since I did not move the 1 M resistors from the inputs to the tube pins that that could be the source of my noise? If not could it be the length of the 68k resistor leads or the length of the .1 uf capacitor leads between the 68 k resistors and the tube pin? otherwise everything is very tidy. If it were a lead dress issue, and there is no noise when VRM not activated, could you point me to an area to inspect? Thank you for your help. I can post some pictures as well if you need me to.

cheers

Please post pics. the 68K should be as close to the pin as possible. The 1M really shouldbe moves as shown in the drawing, but I dont think the source of noise.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Stephen, here are the pictures of the 68 k resistors at the tube pins. please let me know if you think that could be the source of the noise. there is only noise when the VRM is engaged otherwise it is dead silent. thank you

What about the lead dress around the VRM control, can you snap a picture of that.
This looks OK, except for the 1M resistor.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

Stephen,
sorry it took me so long to get the additional pictures I have been swamped, and traveling everyday including weekends, anyways here is the pic of the VRM

All I can suggest is to braid the wires from the board to the control. They dont have to be shielded. I never do. Just use some 22Ga, twisted together or braided from control pot to board. How far away is the board from the control?

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps

the VRM is towards the back of the amp. but still close the transformer. I guess that is why I used the shielded wire. I will try to move the whole VRM rig to the front of the amp as close as possible to the Pot so that I can use a very short run of wire from the VRM to the pot. I will let you know how it goes, I know it is not supposed to be this difficult.

cheers!

No it's not, but you can try standard wires , twisted first, before you move it.

_________________
Stephen
Web: www.trinityamps.com. Facebook: facebook.com/trinityamps. Twitter: @trinityamps