C3G headphone amp
My first one...
My headphone amplifier using the Siemens c3g, a post tube from the 60's...
I found the schematic on a german forum and immediately liked it for its simplicity. Building the beast took some time, and chasing down some hum issues took me a bit more...;-)
The amp has a large psu with 2 chokes and smallish mkp capacitors (33-22-15 uF) and uses a 5R4 for rectification. In its latest wiring scheme the amp is absolutely dead quiet and just makes music...
and very fine indeed!!
My first one...
My headphone amplifier using the Siemens c3g, a post tube from the 60's...
I found the schematic on a german forum and immediately liked it for its simplicity. Building the beast took some time, and chasing down some hum issues took me a bit more...;-)
The amp has a large psu with 2 chokes and smallish mkp capacitors (33-22-15 uF) and uses a 5R4 for rectification. In its latest wiring scheme the amp is absolutely dead quiet and just makes music...
and very fine indeed!!
Attachments
SE
Hello.. the plate shows a bright red orange color ,especially in dark room. The topology is class A with grid current without interstage transf. direct from the precedent cathode follower tube.The heatsinks is for the regulated PSU for the 250th heaters .Six transistors for 10,5A 5V tension. No any hum noise and powerfull excellent sound ,,but very hot.. 🙂
Hello.. the plate shows a bright red orange color ,especially in dark room. The topology is class A with grid current without interstage transf. direct from the precedent cathode follower tube.The heatsinks is for the regulated PSU for the 250th heaters .Six transistors for 10,5A 5V tension. No any hum noise and powerfull excellent sound ,,but very hot.. 🙂
RE084K is old german Triode used in many thousand Radios and old equipment.
Personally I don't fancy using this Tube for new (so called High-End) Audio. There are lots of Radios which need it or people restoring old radios and need it.
Simon
Personally I don't fancy using this Tube for new (so called High-End) Audio. There are lots of Radios which need it or people restoring old radios and need it.
Simon
RE084
The RE084 tube is an pure linear audio tube with excellent curves, this tube was used by Neumann for the old tube microphone CMV3..also the last letter K [RE084K] means no microphonic. and this is the special version..Gianis
The RE084 tube is an pure linear audio tube with excellent curves, this tube was used by Neumann for the old tube microphone CMV3..also the last letter K [RE084K] means no microphonic. and this is the special version..Gianis
My modified Dynaco ST70 with vintage cloth lead output transformers, SS rectifiction, 4894uF in power supply, 10H 500mA 20R DCR choke, 12AU7 input tube, 12BH7 driver tubes and 6550 output tubes.
Output is 2x44W RMS with this transformer, which is too small (215VA), as it will give 2x60W RMS with my other transformer (500VA).
Output is 2x44W RMS with this transformer, which is too small (215VA), as it will give 2x60W RMS with my other transformer (500VA).
Attachments
Completed the upgrade on my ST70!🙂
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Now that is real shinny 🙂
I'm not a big fan of those binding posts thou... and i guess the stock chassis dictates the tight spacing.
How does it sound? What front end did you end up using?
dave
I'm not a big fan of those binding posts thou... and i guess the stock chassis dictates the tight spacing.
How does it sound? What front end did you end up using?
dave
Hi dave,
I'm using an entry level ttable which is GR1.2 and pairing the amp with frank de grove's buffered linestage MM preamp. Initial impression is lots of details and richer tone from this upgrade!
I'm using an entry level ttable which is GR1.2 and pairing the amp with frank de grove's buffered linestage MM preamp. Initial impression is lots of details and richer tone from this upgrade!
By front end i meant what driver stage in the amp (not that the other info isn't appreciated 🙂)
dave
dave
