This topic probably been beat around alot, SE 6C33C build. So My start is a cache of 6C33C tubes, 2 Lundahl xfrmrs and 2 ripped apart tektronix type 160A power supplies.
I am a tech and tube amp hobbyist... I have built 4 or more guitar amplifiers from scratch...following fender circuits. And have rebuilt 2 Heathkit W5ms.. all new components. HK Citation II kept running in my front room for years.
Any way if someone here has been down this road and could throw me some pointers that would be great.
I am a tech and tube amp hobbyist... I have built 4 or more guitar amplifiers from scratch...following fender circuits. And have rebuilt 2 Heathkit W5ms.. all new components. HK Citation II kept running in my front room for years.
Any way if someone here has been down this road and could throw me some pointers that would be great.
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I have built one 6C33C amp before.
If I had to do it again, I would use a choke loaded 6J52P and run it off the B+ rail for the 6C33. I wasted a lot of time and money making a separate high voltage rail and running 6SN7 type drivers, but that was a waste of time.
If I had to do it again, I would use a choke loaded 6J52P and run it off the B+ rail for the 6C33. I wasted a lot of time and money making a separate high voltage rail and running 6SN7 type drivers, but that was a waste of time.
assuming a single chassis construction,
filaments will need about 82 watts for two 6c33 tubes, and 120 watts for plate power, so then 200 watt secondary....at the very least at 350 va power traffo...for stereo.....
i built one before...My Russian SET
i built the SE opt, 800:8 ohms or a 10:1 turns ratio, just two sections, split primary and single secondary....
filaments will need about 82 watts for two 6c33 tubes, and 120 watts for plate power, so then 200 watt secondary....at the very least at 350 va power traffo...for stereo.....
i built one before...My Russian SET
i built the SE opt, 800:8 ohms or a 10:1 turns ratio, just two sections, split primary and single secondary....
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Hi Steve,
the first thing you need is whether you want heating on one or both cathodes of 6C33C. As you can see on the curves, heating on one cathode has slightly nicer curves. Besides, in summer it is better for your room 🙂)
Second, each driver for the 300B SET is appropriate for the 6C33 SET. Forget 6SN7 and the like ...
Personally, I have a D3a in triode mode.
Best DIYing
the first thing you need is whether you want heating on one or both cathodes of 6C33C. As you can see on the curves, heating on one cathode has slightly nicer curves. Besides, in summer it is better for your room 🙂)
Second, each driver for the 300B SET is appropriate for the 6C33 SET. Forget 6SN7 and the like ...
Personally, I have a D3a in triode mode.
Best DIYing
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Some of the ideas in the 6c33 survival guide seem worthwhile to follow. Like the warm up time and burning in the tubes with a little current before going full blast. Thoughts? GoodSoundClub - Romy the Cat's Audio Site - The short "6C33C Survival Guide".
I have built 6c33c se based on the "SIMPLEX" circuit. The driver is 6gu7 (but also works with 6CG7 and 6n6p with a slight adjustments).
Heaters powered from 6.3V. There ar no hum at all - practically the quietest amplifier I have built.
Fixed bias very stable, there has never been a need to adjust it after the initial adjustment with new tubes. CLCRC type PSU. dual mono construction.
Anode voltage for 6c33c around 205V and bias 200mA.
I add some pictures (enclosure and meters from eaby holes cutted with CNC)
Heaters powered from 6.3V. There ar no hum at all - practically the quietest amplifier I have built.
Fixed bias very stable, there has never been a need to adjust it after the initial adjustment with new tubes. CLCRC type PSU. dual mono construction.
Anode voltage for 6c33c around 205V and bias 200mA.
I add some pictures (enclosure and meters from eaby holes cutted with CNC)
Attachments
I'm curious as to what schematic you will follow, or come up with.
Have you considered a different OPT?
A max of 185ma DC isn't a whole lot of head room for the 6C33C-B. Look at the datasheet, and some of the typical operating parameters for it. I guess you could describe it as a current hungry tube.
Hammond and Edcor both have 600ohm OPT that can handle 250ma, and Toroidy has one that can handle 600ma.
Have you considered a different OPT?
A max of 185ma DC isn't a whole lot of head room for the 6C33C-B. Look at the datasheet, and some of the typical operating parameters for it. I guess you could describe it as a current hungry tube.
Hammond and Edcor both have 600ohm OPT that can handle 250ma, and Toroidy has one that can handle 600ma.
Thanks for the replies. And I am amazed at the builds. So tell me is this amplifier worth building. I have never heard an SE amplifier. I have several great PP amps and chose the 6c33c because I am anticipating SE with tight bass.
My first chore is to work out the power
+300 V output DC, unregulated, 250 mA max
+225 V output DC, regulated, 175 mA max
+150 V output DC, regulated, 15 mA max
+70 V output DC, unregulated max load?
−170 V output DC, regulated, 125 mA max
6.3 V output AC, unregulated, 20 A max
The tektronic PS has the above specs when functional the 2 I have are stripped of the wiring but the are intact minus tubes. Would it be worth rebuilding from the schematic?
+300 V output DC, unregulated, 250 mA max
+225 V output DC, regulated, 175 mA max
+150 V output DC, regulated, 15 mA max
+70 V output DC, unregulated max load?
−170 V output DC, regulated, 125 mA max
6.3 V output AC, unregulated, 20 A max
The tektronic PS has the above specs when functional the 2 I have are stripped of the wiring but the are intact minus tubes. Would it be worth rebuilding from the schematic?
