6V6 line preamp

[WntrMute2]

There has been a lot of talk here about microphonety of the 6V6 tube. Has anyone tried tube dampers either silicone o-rings or the Herbie type dampers?

 

[WntrMute2]

What about if you spaced the aluminum plate 1/4 inch or so off the wood base?

 

[WntrMute2]

The problem with mechanical noise from the transformer solved.
the only problem that remain is big temp inside the box, on aluminium surface i can measure 44-48 Celsius degrees , temp air about 30 Celsius degrees.

Could you space the top plate 5mm or so above the wood frame? You'd get good airflow all around the perimeter.

 

[Nikos]

Thanks my friend WntrMute2, i will try it ..

 

[kodabmx]

I'd get rid of that masking tape holding the power resistors together. The glue on masking tape dries out in weeks and the resistors will fall apart.
Just use longer screws.

 

[Nikos]

Thanks Kodabmx....
It is an old pic only for testing. Now there is only one resistor with proper value to get 360V before the Salas Reg..

 

[WntrMute2]

@Nikososkey. Could you provide a little more info on how you built your heater regulators and HV regulators? I love how you used the brackets to make use of the allowable space.

 

[Nikos]

@Nikososkey. Could you provide a little more info on how you built your heater regulators and HV regulators? I love how you used the brackets to make use of the allowable space.

My heaters regulators based on Salas L-Adapter
L-Adapter
GB for Salas L-Adapter Board

And the HV regulator it is the Salas reg
Simplistic Mosfet HV Shunt Regs
GB for Salas SSHV2 regulator

 

[democles]

I made this,and its alive.

6V6 preamp maar dan anders - forum.zelfbouwaudio.nl

YouTube

 

[jhstewart9]

Looks OK, no smoke! But why did you throw away 2/3 of the gain?

 

[democles]

With the pot on 1/4 i got max power.To mutch!

 

[jhstewart9]

Salas L Adapter

If any of the 10 LEDs fails open the output volts will go high. An electronic crowbar sensing a preset current would be good insurance.

 

[democles]

Only 3 LED,s ,fore 6,3v?

 

[jhstewart9]

Some Typical LEDs HP 1980

Some tests I ran a while ago. As the wavelength becomes shorter, red to green, the forward volts increase. Yellow & orange in between, Blue higher volts.

 

[Eslheadphone]

Just heard the 6v6 preamp at the BAF 2019. I am building one.

 

[democles]

 

[democles]

Some tests I ran a while ago. As the wavelength becomes shorter, red to green, the forward volts increase. Yellow & orange in between, Blue higher volts.

Yes? sow what?

 

[democles]

The 6,3v glow is fine. Nice yob Salas



I will try some feedback later.

 

[Salas]

Nice video*. So your build has L-Adapters for heaters on home made boards, also planning SSHV2 for B+. A BJT bias addition in the circuit. Why, you wanted to can scan for sweet spots?

*Weird I ordered a used cassette of the Synchronicity album by The Police just a few days ago featuring the original song from 1983.

 

[Salas]

Just heard the 6v6 preamp at the BAF 2019. I am building one.

Who presented it in Burning Amp?