6C45 preamp
Ryssen at 15-20 mA you should expect perfomace similar to your pentode 6c45 design you have now. There are a wide choice of CCS in the Solid State world, Gary Pimm and Bas Horneman both have done a lot with these as well as Doc Bottlehead. I have posted my variation earlier. Gary Pimms self bias CCS is nice. http://www.pacifier.com/~gpimm/self_bias.htm
Ryssen said:
I´ve heard that to,the dull thing,and I thought about a CCS at the tail to Yeah, you may bee right about that to..If I decide to go that way with a CCS loaded 6C45 will 15-20mA be enough?thats what I have to play with.
And I would be happy if someone could explain what the 15,5v at the gates on SEWA does.
Ryssen at 15-20 mA you should expect perfomace similar to your pentode 6c45 design you have now. There are a wide choice of CCS in the Solid State world, Gary Pimm and Bas Horneman both have done a lot with these as well as Doc Bottlehead. I have posted my variation earlier. Gary Pimms self bias CCS is nice. http://www.pacifier.com/~gpimm/self_bias.htm
Could you please point me to the article,and others if there are any.May I suggest you read the Tubecad article on the technique and come back better informed.
http://www.tubecad.com/march2001/2001_03.pdf.
I think Wavebourn is partial to a bit of trolling judging from his contributions to a number of threads.
Shoog
I think Wavebourn is partial to a bit of trolling judging from his contributions to a number of threads.
Shoog
hello
Ryssen ( lineup lives near to you, I think )
www.tubecad.com
If you scroll down you have articles like:
http://www.tubecad.com/articles_2003/Grounded_Cathode_Amplifier/index.html
Grounded-Cathode Amplifier
The grounded-cathode amplifier is approaching its centennial (2007) and it remains the building block of most tube audio equipment. It is simplicity itself, with little more than a few resistors and a triode; yet many are ignorant of its inner workings.
19 Jan 2003 PDF
I dont know what article meant:
May I suggest you read the Tubecad article on the technique and come back better informed.
I wouldnt just throw out an advice to read
and forget to give exact link to project, for example:
DoZ Headphone Amp - A New Use For The Class-A Power Amp
Rod Elliott (ESP)
Updated 03 Oct 2005
.. actually I wouldnt think basic version has enough gain for SEWA preamp
But the HEADPHONE version of DOZ PreAmp should have
enough OUTPUT CURRENT to drive most any power amplifier input
linep audio advisor
Lineup Audio Labor Party
Ryssen ( lineup lives near to you, I think )
www.tubecad.com
If you scroll down you have articles like:
http://www.tubecad.com/articles_2003/Grounded_Cathode_Amplifier/index.html
Grounded-Cathode Amplifier
The grounded-cathode amplifier is approaching its centennial (2007) and it remains the building block of most tube audio equipment. It is simplicity itself, with little more than a few resistors and a triode; yet many are ignorant of its inner workings.
19 Jan 2003 PDF
I dont know what article meant:
May I suggest you read the Tubecad article on the technique and come back better informed.
I wouldnt just throw out an advice to read
and forget to give exact link to project, for example:
DoZ Headphone Amp - A New Use For The Class-A Power Amp
Rod Elliott (ESP)
Updated 03 Oct 2005
.. actually I wouldnt think basic version has enough gain for SEWA preamp
But the HEADPHONE version of DOZ PreAmp should have
enough OUTPUT CURRENT to drive most any power amplifier input
linep audio advisor
Lineup Audio Labor Party
lineup said:DoZ Headphone Amp - A New Use For The Class-A Power Amp
Rod Elliott (ESP)
Updated 03 Oct 2005
.. actually I wouldnt think basic version has enough gain for SEWA preamp
But the HEADPHONE version of DOZ PreAmp should have
enough OUTPUT CURRENT to drive most any power amplifier input
linep audio advisor
Lineup Audio Labor Party
actually looking at the schematic,
the VOLTAGE GAIN of DOZ HEadPHONE AMP is
(R9+R4) / R4
2920/220= 13.27272727
Maybe we would need something like ~20.0
No problem for me to change resistor and get good gain for SEWA
actually this is OFF TOPIC,
and should be in SEWA original TOPIC in Pass Laboratories
... but as I started this TUBES topic Myself ( halojoy )
I take me some unique rights here
An externally hosted image should be here but it was not working when we last tested it.
The Output transistors are Motorola MJL4281, N-Channel !!!
http://www.datasheetarchive.com/datasheet.php?article=2397671The MJL4281A and MJL4302A are PowerBase power transistors
for high power audio.
• 350 V Collector−Emitter Sustaining Voltage
• Gain Complementary:
Gain Linearity from 100 mA to 5 A
High Gain − 80 to 240
hFE = 50 (min) @ IC = 8 A
• Low Harmonic Distortion
• High Safe Operation Area − 1.0 A/100 V @ 1 Second
• High fT
>> http://lineup.awardspace.com/ <<<
Cool!This schematic will be work perfec with a E88CC(I have some of this-Philips Special Quality with gold pinshoktuna said:This is my preamp i am use and i hope it will drive my sewa.
).Try with her and say something for the BIG sound.
Does the signal get a reduction of 8 times then?Trafo is Lundahl conect backwards 8:1.
I have been bussy with this SEWA hybrid thing
It´s a 6c45 CCS stage:
It seems to be working fine through my junkspeakers,the only problem now is that i found out (Thanks Fuling)the supply for the tubes are a bit weak.I can use 15ma/tube but if I go higher I only get hum,will order a bigger trafo wich I use backwards on the SEWA supply,and try it out on my better speakers.
cheers.
An externally hosted image should be here but it was not working when we last tested it.
It´s a 6c45 CCS stage:
An externally hosted image should be here but it was not working when we last tested it.
It seems to be working fine through my junkspeakers,the only problem now is that i found out (Thanks Fuling)the supply for the tubes are a bit weak.I can use 15ma/tube but if I go higher I only get hum,will order a bigger trafo wich I use backwards on the SEWA supply,and try it out on my better speakers.
An externally hosted image should be here but it was not working when we last tested it.
cheers.
Ryssen said:Maybee I should add that B+ dropps from 220v to about 150v under load,30mA..
What is a voltage on a power supply when you get 120V on plates of your triodes? What is the current through tubes?
Ryssen said:Well there is about 140v at the plates and 15mA throug the tube,cannot go higher,then comes the hum and the Leds fade out.
And what is the voltage on the power supply at this time?
It seems to be something like 145V, right?
Ryssen said:Yes, 145-148v I think,and the Leds draw about 20-25mA to.
Ok, now - what voltage swing do you need for your power stage?
Connect sine source to input of your amp and slowly decrease a current until you get your needed swing on output without clipping.
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