Subminiature Tube Compressor

[wakeuptone]

Anyone build Subminiature Tube Compressor operate with 12v

[frequencycentral]

I recently breadboarded a 6111 and VTL5C3 based optical submini tube compressor at 12v. The results suggested that to get enough gain to get enough squeeze to be a decent compressor a higher voltage is needed, and maybe a higher gain tube such as 6112. Gonna try it again soon with a few modifications.

[wakeuptone]

I recently breadboarded a 6111 and VTL5C3 based optical submini tube compressor at 12v. The results suggested that to get enough gain to get enough squeeze to be a decent compressor a higher voltage is needed, and maybe a higher gain tube such as 6112. Gonna try it again soon with a few modifications.

Thank you for your information.  I read many of your posts here and know that you're very special in subminiature tube.  Once you complete the project, could you please share the information.

[Johan]

but that would end up being an optical comp/limiter, with tubes...for tube compressor, search google for "PRR Vari-mu"...I doubt you could get it working well with low voltage, but PRR is a member here and might have ideas for that too...

[derevaun]

This thread is relevant to my interests. Please let us know what develops!

[thedefog]

Would it be difficult to get a smaller sized transformer inside a pedal case to run them at a higher plate voltage? I'd imagine you're loosing headroom running at that low a voltage, but I've never played with these so I have no practical knowledge. All I know is that from building a tube amp that you want to run tubes at their recommended plate voltage in order to get the full benefit from them (voltage swing).

[Earthscum]

Would it be difficult to get a smaller sized transformer inside a pedal case to run them at a higher plate voltage?

Who needs iron? There are charge pumps and other silicon solutions that work great for that. The plate voltages may need to be high, but the current requirements (for our purposes) are quite low. Most of the power draw is from the heater current, if I'm not mistaken.

[thedefog]

Would it be difficult to get a smaller sized transformer inside a pedal case to run them at a higher plate voltage?

Who needs iron? There are charge pumps and other silicon solutions that work great for that. The plate voltages may need to be high, but the current requirements (for our purposes) are quite low. Most of the power draw is from the heater current, if I'm not mistaken.

That's an excellent point. But a 9v source won't get you up to 100+v with a charge pump, so you'd still need some sort of higher voltage adapter going into it, no? My knowledge of charge pumps and whatnot is limited to the Maxx1044.

[frequencycentral]

But a 9v source won't get you up to 100+v with a charge pump...

Yes it will. 

But there are other ways too: http://www.diystompboxes.com/smfforum/index.php?topic=74088.0

[petemoore]

  For all the efforts...
  36volt or so adapters and applicable regulators make tube-build at safe to handle voltages...easy access.
  Say the tube calls 50vdc plate V max, 36 gets you more of your 'tube value', easier in some ways, just a little bigger and a little uglier...

[thedefog]

But a 9v source won't get you up to 100+v with a charge pump...

Yes it will. 

But there are other ways too: http://www.diystompboxes.com/smfforum/index.php?topic=74088.0

That is pretty awesome. I wish I had know this earlier. Takes pedal building into a whole new realm.

[wakeuptone]

Rick.... Did you complete the tube compressor project.?

[frequencycentral]

Backburner ATM. I tried with a 6111 but changed to a 6112 at high voltage. Nice clicky attack but too much ripple on release. Need to work on it some more sometime. Maybe using an incandescent bulb instead of a LED.