I forgot to visit this thread and I apologize that I have not responded to your questions voxac30 but I will try to answer as I got to. I have forgotten how the circuit works but I read tonight on how it works and come back when I studied my documents in detail.
Power supply is a straightforward history built on two transformer one to each circuit and AC heating for the power tubes.
I bought my OPT directly from Ari.
The sound of the amp have very good flow in the music and soul lots of micro dynamics, it is not tireing of listening to music, contrary.
I insert a picture on my OPT so you can determine if your OPT suit.
Anders
Hi K.A.B
Can you show us the schematic diagram for your amp? You use two 6c33c in paralel? the primary impedance is 350ohmi?
Thanks
Can you show us the schematic diagram for your amp? You use two 6c33c in paralel? the primary impedance is 350ohmi?
Thanks
Ok I have registered later about sportsman -what a hell
he have to do with 6c33 -haha🙄 I,m moving to
Austria -Graz ,so at 1.4. I will be home in MB .You know my
friend audio man -yezek from MB ? I,m yeti.😉
Hello everybody,
My name is José, I live in France and I reply to this post because I am currently building a SE6C33C amp based on Borbelyaudio's diagram.
My question for Gabriel: could you please let us know your power supply diagram? I am getting mad in finding the right transformer.
In advance thanks.
Regards.
José
My name is José, I live in France and I reply to this post because I am currently building a SE6C33C amp based on Borbelyaudio's diagram.
My question for Gabriel: could you please let us know your power supply diagram? I am getting mad in finding the right transformer.
In advance thanks.
Regards.
José
Hi Jose
For the power supply I use two transformers, one is EI transformers E120 20cm2 300VA this is for 6C33C anode voltage, 6SN7, 6J5 anode voltage, bias voltage and 6SN7 6J5 filament voltage, second is toroid transformers for 6C33C filaments 2x12.6V 8A.
For the EI transformers the diagram is very simple, you must double the current from the Borbely diagram, the schematic in the PDF is for only one channel if you want to make two mono blocks. I make only one enclosure so I use one transformer.
6C33C anode 210v AC 1A
6SN7 6J5 anode.290v AC 80mA
Bias 90v AC 50mA
6SN7 6J5 filament 6.3V 2.5A
I made also a 12.6v 1.5A for remote module and anode timer used for 6c33c anode voltage
After I start the amplifier my 6C33C anode voltage start after 2 minutes.
Good luck and keep us in touch
I hope to finish my enclosure this week
Best regards
For the power supply I use two transformers, one is EI transformers E120 20cm2 300VA this is for 6C33C anode voltage, 6SN7, 6J5 anode voltage, bias voltage and 6SN7 6J5 filament voltage, second is toroid transformers for 6C33C filaments 2x12.6V 8A.
For the EI transformers the diagram is very simple, you must double the current from the Borbely diagram, the schematic in the PDF is for only one channel if you want to make two mono blocks. I make only one enclosure so I use one transformer.
6C33C anode 210v AC 1A
6SN7 6J5 anode.290v AC 80mA
Bias 90v AC 50mA
6SN7 6J5 filament 6.3V 2.5A
I made also a 12.6v 1.5A for remote module and anode timer used for 6c33c anode voltage
After I start the amplifier my 6C33C anode voltage start after 2 minutes.
Good luck and keep us in touch
I hope to finish my enclosure this week
Best regards
Hi Gabriel,
Thank you very much for your answer. Most people to whom I have talk about this project in France, told me that the tube 6c33c is a very difficult tube and at the beginning I doubt about continuing my project, but I decided to go on.
The figures you gave in your reply do not correspond exactly to the Borbely's, but I've seen that you are happy with the result. I think this is the aim, being happy at the end with what we have done.
I will no do a tween mono, just stereo. If I understood well, by using a single transformer, you need to double the current of Borbely's diagram...??
I do not know if you have it, or even if you can drawn just with a pen, but if you were able to sen me your diagram, it would help me a lot. You can ude the following e-mail or post it here: jrmetr@gmail.com if ever.
By the way, I had at the beginning bought OPT:
600OHM SE AUDIO OUTPUT TRANSFORMER FOR 6C33C,6AS7 - eBay (item 230440523575 end time Mar-02-10 22:12:04 PST)
but again, some people told me that they weren't good. I am still expecting them, since they take 2 months to arrive ??!!
But the power transformer I haven't found yet.
Best Regards.
José
Thank you very much for your answer. Most people to whom I have talk about this project in France, told me that the tube 6c33c is a very difficult tube and at the beginning I doubt about continuing my project, but I decided to go on.
The figures you gave in your reply do not correspond exactly to the Borbely's, but I've seen that you are happy with the result. I think this is the aim, being happy at the end with what we have done.
I will no do a tween mono, just stereo. If I understood well, by using a single transformer, you need to double the current of Borbely's diagram...??
I do not know if you have it, or even if you can drawn just with a pen, but if you were able to sen me your diagram, it would help me a lot. You can ude the following e-mail or post it here: jrmetr@gmail.com if ever.
By the way, I had at the beginning bought OPT:
600OHM SE AUDIO OUTPUT TRANSFORMER FOR 6C33C,6AS7 - eBay (item 230440523575 end time Mar-02-10 22:12:04 PST)
but again, some people told me that they weren't good. I am still expecting them, since they take 2 months to arrive ??!!
But the power transformer I haven't found yet.
Best Regards.
José
Hi José,
what was then the reason to buy this?
(I'm sure you know some good and "not to expensive" European OT producers too.)
Cheers,
Hi,
Well, as I said, you always have people complaining about things. I bought them because I was (I am) sure that they are going to work well.
Regards.
José
Well, as I said, you always have people complaining about things. I bought them because I was (I am) sure that they are going to work well.
Regards.
José
Yezek? Everybody knows him! 😎
Yeti? Snowman personally?! No?! 🙂
BTW, didn't we met each other - once upon the time (on Himalaya)? 🙂
Cheers,
Hi Jose
In did if you want to make only one case for the amp you can make one power transformer and double the current from the Borbely diagram.
Believe me I am also newbie in tubs amplifiers, it is my first tube amplifier I made but I decide to make it with 6c33c because use less voltage than other tubes, is not expansive like 300B or 845 and you have a lot of power 22W. The power transformers is custom made, we have small company who made custom transformers. The output transformers are also made by an engineer from Romania a friend of mine. If you don’t like what you receive maybe we can arrange to send me the Chinese transformers and make another using the Iron if is good.
At the beginning I was tempted to buy from China the OPT but I prefer to make them in Romania with better quality and also more expansive.
Don’t be afraid about this tube, most of the people said that this tube is not good after they see the specification. From my experience this tube is fantastic and believe me I listen a lot of pricey amplifier solid state and tubes. The amp is not cheap I spend about 1000 euro. I use only very good quality components.
Good luck and keep us in touch
Some pictures with my case not finished yet
In did if you want to make only one case for the amp you can make one power transformer and double the current from the Borbely diagram.
Believe me I am also newbie in tubs amplifiers, it is my first tube amplifier I made but I decide to make it with 6c33c because use less voltage than other tubes, is not expansive like 300B or 845 and you have a lot of power 22W. The power transformers is custom made, we have small company who made custom transformers. The output transformers are also made by an engineer from Romania a friend of mine. If you don’t like what you receive maybe we can arrange to send me the Chinese transformers and make another using the Iron if is good.
At the beginning I was tempted to buy from China the OPT but I prefer to make them in Romania with better quality and also more expansive.
Don’t be afraid about this tube, most of the people said that this tube is not good after they see the specification. From my experience this tube is fantastic and believe me I listen a lot of pricey amplifier solid state and tubes. The amp is not cheap I spend about 1000 euro. I use only very good quality components.
Good luck and keep us in touch
Some pictures with my case not finished yet
Attachments
Hai Gabriel,
Thank you for your answer.
Your case looks very solid and really nice, I like it very much.
In fact, I am intending to do just stereo in one case, as you.
The OPT take a long time to arrive, maybe still one month. The guy said it takes 80 days because it's shipped by boat. Probably I will do as you said, to rewire the iron. Do you know how much it cost?
I have seen some people complaining about the tube 6c33c, but I have seen also many other saying that it is fantastic. I prefer to believe the second.
Best regards.
José
Thank you for your answer.
Your case looks very solid and really nice, I like it very much.
In fact, I am intending to do just stereo in one case, as you.
The OPT take a long time to arrive, maybe still one month. The guy said it takes 80 days because it's shipped by boat. Probably I will do as you said, to rewire the iron. Do you know how much it cost?
I have seen some people complaining about the tube 6c33c, but I have seen also many other saying that it is fantastic. I prefer to believe the second.
Best regards.
José
Hi Jose
You must change some values in the Borbely supply diagram.
D14-D15-D16-D17 must be Schotiky 60V 3A not 1.1A.
D9 on bias must be 20V not 30V Zener and R3 also on bias from 25k to 47K, after this modification you can adjust the bias voltage between -62 and -85V. The 6c33c is unstable in the first 50 hours of work and you must adjust the bias all the time. Usually this tube at -72V bias must stay at 210mA at 210V anode voltage.
I will inform you how much will cost the rewinding the transformers, but my opinion is to try them first after you will receive them.
See the post 136 to see the output transformers diagram that I use
Good luck
You must change some values in the Borbely supply diagram.
D14-D15-D16-D17 must be Schotiky 60V 3A not 1.1A.
D9 on bias must be 20V not 30V Zener and R3 also on bias from 25k to 47K, after this modification you can adjust the bias voltage between -62 and -85V. The 6c33c is unstable in the first 50 hours of work and you must adjust the bias all the time. Usually this tube at -72V bias must stay at 210mA at 210V anode voltage.
I will inform you how much will cost the rewinding the transformers, but my opinion is to try them first after you will receive them.
See the post 136 to see the output transformers diagram that I use
Good luck
Hi Gabriel,
Thanks for the information. I wait for the cost of rewiring.
In the mean time, do you think I can buy a custom made power transformer to the company you talk in the previous messages? What I would like is a good power transformer for this project, that includes all the output voltages; I wouldn't like to use 2 transformers for the supply.
Regards.
José
Thanks for the information. I wait for the cost of rewiring.
In the mean time, do you think I can buy a custom made power transformer to the company you talk in the previous messages? What I would like is a good power transformer for this project, that includes all the output voltages; I wouldn't like to use 2 transformers for the supply.
Regards.
José
Hi Jose
The power supply transformer is about 100 euro without shipping to France. Has about 6kg and you can install underneath. It is a toroid transformer.
Best regards
The power supply transformer is about 100 euro without shipping to France. Has about 6kg and you can install underneath. It is a toroid transformer.
Best regards
Hi Gabriel,
You are not using a toroid transformer in your project and I have rarely seen this kind of transformer for tube amps. What are the caracteristics, secondary voltages and ampers?
José
You are not using a toroid transformer in your project and I have rarely seen this kind of transformer for tube amps. What are the caracteristics, secondary voltages and ampers?
José
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