VHT 2150 Bias Question

B

braintheory

Well-known member
Please forgive me in advance if this question seems newbish. I’m not a tech savvy guy. So I got recently a 2150 and want to now try out some of my various vintage 6550’s I’ve got in it. I know how to bias amps (have done it many times now), but am just trying to be more cautious now when I do it to not risk shocking myself. As you can see in the pics below the bias pot is actually able to be accessed from both above or below where the board is (where that hole is near the transformer), so it seems convenient. Just wanted to ask if there is anything in the top I need to be careful about not to touch (besides the capacitors). Trying to be as safe as I can. Will of course try not to touch anything but the plastic screw driver handle. I would try the tube swaps on the side of the Poweramp without the capacitors
 

Attachments

  • 8AA1C7BC-565A-406A-98D3-56432576D954.jpeg
    8AA1C7BC-565A-406A-98D3-56432576D954.jpeg
    3 MB · Views: 56
  • 2F09ED20-E0AF-4635-ABAA-A27BAAB063B2.jpeg
    2F09ED20-E0AF-4635-ABAA-A27BAAB063B2.jpeg
    3.9 MB · Views: 65
glpg80 said:
The tops of those caps of course.

Otherwise the tubes get hot 😂
Click to expand...
That’s what I thought and why I will do the side without those caps lol. And I’ve been burned plenty of times now from hot tubes or my soldering iron. That doesn’t worry me
 
She will bite if you are not careful :yes:

First, I'm not an EE nor and amp tech. Maybe there is something about the 2150 that I am not aware of. Are you guys saying that touching the outside of cap can in one of these amps will shock you? I'd be shocked if that were the case. Nothing on the top side of the chassis should shock you if it is working properly. Correct?

braintheory - I made a biasing tutorial some time back because I was once very new and novice to this. I felt a lot of the biasing info out there was skipping a lot of safety steps so I decided to get as detailed as I could. I know you said you've biased before and this may be worthless to you but I thought I'd share anyway:

https://splawnfans.proboards.com/thread/7786/amp-biasing-tutorial

Also, this looks helpful:
http://www.fryette-users.com/forums/archive/index.php/t-2532.htmlhttps://www.rig-talk.com/forum/threads/need-help-biasing-a-vht-2150-can-anyone-help-please.61726/
 
No, touching a cap will not hit you unless it's near one of the leads and it discharges into you. Pleanty of videos on YT about this so educate yourselves bf you try anything inside a tube amp.
 
Y’all better watch yourself. Touching the cap itself isn’t the issue, it’s the top of the cap.

Some are exposed and not all are ground referenced. Some added an insulator like plastic or mica to the top to prevent accidental discharge, but if you’re poking around just know what you’re messing with.

And I am an EE.
 
A lot of those are tools I’ve had since back when I was a prototype technician that I’ve had for years. Others just personal preference to what I like.

Hey man tools are tools! I use what works!
 
You must log in or register to reply here.
Back
Top