SINGLE ENDED EL34 FIX BIAS

Single Ended Parallel 6V6 / 6N2P Fix Bias

ecc83 tube preamp

tube preamp based on ecc83 , single gain stage with voltage gain approx 40. plate voltage is 230vdc.
power transformer using back to back 12v-0-12v secondary (500ma) .heater voltage 12.4vdc.

Darling Amp in local wooden box

3rd project based on Darlin Amp by Bob Danialek. Single output tubes per channel , driven by Russian Super tubes 6N2P , which has gain/character similar to 12ax7 . plate voltage power tubes ~280v , plate current draw 28mA on both tubes. 

Ivan's double 'darling' amp

This amp built for Ivan Sia from Mexter Bhd .  2x 1626 each  left and right putting about 4 watt in total.

NOS JAN -join army navy tubes - from USA . made in  1960.

 

plate voltage 260v, primary output impendence is 5k, but actual need about 3.5k (based on bob danialek schematic)

driver using 6n8s which equavelant with 6sn7 .

coupling caps using ampohm from UK. 

1626 darling amp with ecc83

this amp is based on bob danielak  'darling amp ' , there's a lot of version of this amp, original caps coupled,  DC darling, schematic can be found here. .

http://www.reocities.com/bobdanielak/darling.html

basiclly i built it based on original caps coupled schematic, but change the driver /preamp from 8532 to ecc83

  tubes accepted date : nov 1942.  got it from jasonscard1 on ebay.

amp is built on 'experiment' chassis with all the switch ,sockets and output trannies already screw to chassis  .

                                                 guts shot after finishing wiring

plate voltage 1626-255v

output transformer primary impendence-8k

stereo single ended EL34 amp with phono stages

 pre drilled chassis , spraypainted matt white as requested by capten dol 'air'.

 heater and power supply wired first.

 close pic from the back

 copper bus for easy grounding ,combine from left to  right channel.

 complete wiring  ,all signal line is shielded to avoid hum,

amp complete built on nov2010 , with extra preamp stages for phono signal level.
4 x 12ax7 ,2 x el34 in triode mode,
el34 plate Voltage- 304v both left and right.

 el34 (right) current draw -73mA
el34 (left) current draw -80mA
bias point sit exactly at 300V 80mA  , which is max for the plate dissiption.