tube vibration control

[christensenleif@msn.com]

very rarely....we ´ll have to lean on AC

​

 

[DasguteOhr]

D3a is a pentode not a triode. Though can be triode connected. TM does not make DHT phonos but indirectly heated tubes.

I know it,but microphony does not matter whether the tube is labeled pentode or triode.
was only intended as an example of how to eliminate or mitigate the problem

 

[DasguteOhr]

And I agree with all the posts. Vibration dampening of the glass helps, but it's clear that there's also noise coming from the chassis. It is audibly airborn and speaker created.

View attachment 158673

Sometimes it's enough to decouple tube sockets from the chassis using rubber mounts. The problem with this is that the tube socket moves downwards. If the hole in the topplate isn't large enough, the tube pins are too short.

 

[cal3713]

Sometimes it's enough to decouple tube sockets from the chassis using rubber mounts. The problem with this is that the tube socket moves downwards. If the hole in the topplate isn't large enough, the tube pins are too short.View attachment 158746

Yeah, that's my problem, the chassis hole is smaller than my tube base unfortunately.

 

[Kingrex]

Yeah, that's my problem, the chassis hole is smaller than my tube base unfortunately.

Then move them up?

 

[cal3713]

Then move them up?

I have thought about it. I'd have to fully rewire the sockets (they are also wider than the chassis hole) and have them bare out in the open floating above the chassis so it's not ideal. I have considered it though. I bought some parts to build my own homebrew vibration controlled socket extender "just like" the absob gel ones, so I'll see how that goes first.

 

[Kingrex]

Float the transformers. That is where the vibration is coming from.

 

[cal3713]

Float the transformers. That is where the vibration is coming from.

I can hear then light microphonic ringing if I clap loudly. That's certainly airborne, right?

 

[Kingrex]

Vibration comes from everywhere. But I would say transformers and direct contact with a speaker enclosure create the most. I would assume airborne is much lower.

I had to remote locate the crossover to my PAP trio 15 speakers as the frame vibrations were smearing the music. That surprised me how audible it is.