Go Back   Home > Forums > Amplifiers > Tubes / Valves

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 30th April 2013, 05:52 PM   #1
diyAudio Member
 
Join Date: Jan 2009
Location: Bogota, Colombia
Default Newbie wants to build SET 6C33C

First of all HI to everybody in the forum. Some background first. I have a degree as industrial designer and made some undergraduate studies in electronics engineering (never graduated), so I can do some math and can tell the difference between a resistor and a capacitor. I love tubes, I have a Cayin A-50T with EL-34 tubes and some other tube stuff. As everybody else here I want to start building some tube gear, so I can learn really how this stuff works.

I have decided I want to build a 6C33C SET amp. that can deliver around 12 watts, that way I can use the amp with 90dB sensitivity speakers. I want it to have a bandwidth of at least 20hz - 28khz. I hate hum, so it must be canceled in some way. Distortion must be below below 2% at normal power. I am not a purist so I think I will use a solid state power source, and I have no problem in using transistors of MOSFETs to regulate currents in the circuit. I don't want solid state components in the sound path.
  • I would like to know if this requirements can be met? or am I kidding myself?
  • Can someone in the forum send me drawings of 6C33C SET amps already built, so I can take a look at the designs.
  • What driver tubes are recommended to be used with the 6C33C?
  • I can't build the transformers. Are there any commercially available transformers I can use for this project?
Any information is welcomed. Regards,
Julian
  Reply With Quote
Old 30th April 2013, 06:41 PM   #2
diyAudio Member
 
Blaireau's Avatar
 
Join Date: May 2011
Location: Dijon
Default 6S33S

if it can help you, you can have a look at my own designs. The PP Version is really excellent:
__________________
http://constructions.f6fkn.com
  Reply With Quote
Old 30th April 2013, 09:23 PM   #3
diyAudio Member
 
Join Date: Mar 2003
Location: Zürich
Hi Julian,
I don't see any problems with your plans, I already read about getting 18W out of a single 6C33C, so 12W sounds reasonable. A lot of people asked questions about this tube here at the forum: if you search you will find a lot of information and schematics regarding this tube. If you find something with google you can always place a link here so we can comment. 'Romy the cat' (you heard about him?) uses a 6E5P triode wired to drive the 6C33C, but there should be plenty alternatives (maybe use a bifilar Hammond IT, model 126B or 126C depending on driver tube?). For an OPT you may search for INDEL on google, they have a 1k3:8R OPT that would work, and it doesn't cost a lot (even though shipping to Colombia will be expensive, but my experience - at least in BR - is that you can't get OPTs locally , so you will have to import anyway). Or maybe Edcor, in the USA is cheaper on shipment? These are budget suggestions, if money is no problem there is myriad of possible transformer out there!
Good luck, saludos!
__________________
my surname is indeed 'de Best': neither misspelling nor snobbism! Ask SY!
  Reply With Quote
Old 30th April 2013, 10:12 PM   #4
diyAudio Member
 
FullRangeMan's Avatar
 
Join Date: Aug 2009
Location: Brazil
Quote:
Originally Posted by jfbaquero View Post
First of all HI to everybody in the forum. Some background first. I have a degree as industrial designer and made some undergraduate studies in electronics engineering (never graduated), so I can do some math and can tell the difference between a resistor and a capacitor. I love tubes, I have a Cayin A-50T with EL-34 tubes and some other tube stuff. As everybody else here I want to start building some tube gear, so I can learn really how this stuff works.

I have decided I want to build a 6C33C SET amp. that can deliver around 12 watts, that way I can use the amp with 90dB sensitivity speakers. I want it to have a bandwidth of at least 20hz - 28khz. I hate hum, so it must be canceled in some way. Distortion must be below below 2% at normal power. I am not a purist so I think I will use a solid state power source, and I have no problem in using transistors of MOSFETs to regulate currents in the circuit. I don't want solid state components in the sound path.
  • I would like to know if this requirements can be met? or am I kidding myself?
  • Can someone in the forum send me drawings of 6C33C SET amps already built, so I can take a look at the designs.
  • What driver tubes are recommended to be used with the 6C33C?
  • I can't build the transformers. Are there any commercially available transformers I can use for this project?
Any information is welcomed. Regards,
Julian
HI,
Dont use PCBs, add long time reliability to your project and use hard wiring hand soldered.
Make a favor to yourself and DONT use cheap sockets like this crap:
Click the image to open in full size.
Instead use this one(the better option for this tube):
Click the image to open in full size.
Or at least this, that use a kind or Russian baquelite and has the pins semi-loose for not stressing the 6C33 pins/glass seals and is low priced:
Click the image to open in full size.
Please Note the anode pin in this image above, intend that the anode output must be a very thick wire to stand the heat dissipation;

Tube rectification will offer a old fashioned sound, SS rectification will do a modern sound.
To the usual musical, warm tube sound use Input=6SL7 Drive=6SN7
Or If you want low priced Russian Triodes use Input= 6N1P or 6N2P, Drive= 6N6P
An Example: Amps

Some Tubes: ''GSTube.com''. Tubes, sockets etc. Search result for <u>6n1p</u>

IF possible use 5mm aluminium table for heat dissipation and wood sides, avoid steel chassis/table, it is magnetic and low heat dissipation.
¡Buena Suerte!
__________________
>Never go to a psychiatrist, adopt a cat or dog from the streets. On the streets pets live only two years average.

Last edited by FullRangeMan; 30th April 2013 at 10:22 PM.
  Reply With Quote
Old 30th April 2013, 10:46 PM   #5
diyAudio Member
 
Join Date: Mar 2008
Socket:

TUBE SOCKET for 6C33C PLK7-collect /EU locate NEW

I still have them
  Reply With Quote
Old 30th April 2013, 11:04 PM   #6
diyAudio Member
 
Rundmaus's Avatar
 
Join Date: Aug 2005
6S33S is quite a beast for a first project. Heaters require lots of current with the risk of getting hum due to a non-perfect heater wiring...

Quote:
Tube rectification will offer a old fashioned sound, SS rectification will do a modern sound.
With a properly planned power supply, it shouldn't be possible to tell from the sound if its tube or solid state rectification. If you hear a difference, the power supply is poorly planned. Rectification is a part of the power supply. It provides a DC rail with the properties needed by the amplifier, it does *not* do any sound. If it adds anything to the 'sound', build a better power supply.

Rundmaus
  Reply With Quote
Old 30th April 2013, 11:23 PM   #7
AJT is offline AJT  Philippines
diyAudio Moderator
 
AJT's Avatar
 
Join Date: May 2003
Location: Palatiw, Pasig City
i use 12volt heater arrangement, filaments are ac, yet amp is quiet, no hum....My Russian SET
  Reply With Quote
Old 30th April 2013, 11:35 PM   #8
diyAudio Member
 
FullRangeMan's Avatar
 
Join Date: Aug 2009
Location: Brazil
Quote:
Originally Posted by Rundmaus View Post
6S33S is quite a beast for a first project. Heaters require lots of current with the risk of getting hum due to a non-perfect heater wiring...



With a properly planned power supply, it shouldn't be possible to tell from the sound if its tube or solid state rectification. If you hear a difference, the power supply is poorly planned. Rectification is a part of the power supply. It provides a DC rail with the properties needed by the amplifier, it does *not* do any sound. If it adds anything to the 'sound', build a better power supply.

Rundmaus
Thanks for your input. I mention it why it was stated by this builder:
Tube or Solid State Rectification?
Tube vs. SS in amplifiers: Tube rectifiers can be thought of as cushions while SS diodes can be thought of as a concrete pad. The cushioning effect has the ability to make an amp sound more organic and smooth. Sometimes this is desirable.
I would prefer SS rectification for one less valve to retube.
__________________
>Never go to a psychiatrist, adopt a cat or dog from the streets. On the streets pets live only two years average.
  Reply With Quote
Old 30th April 2013, 11:53 PM   #9
diyAudio Member
 
Join Date: Jan 2009
Location: Bogota, Colombia
Thanks for all the enthusiast answers. Here in Colombia is easy and relatively cheap to import things for USA or CANADA. So buying the power and output transformers in the US is my best option, but if there are better transformers available in Europe (lets say something like Lundhal) I would give it a try. I want to use the best components I can afford, ceramic sockets are on the list. I would like to use tubes that are still in production no rare exotic stuff for this project.

I have in stock 6N1P and NOS 6DJ8 tubes, I like the 6N1P because it's low noise.
What about the 6C45PI as drivers, it would be great to use just to tubes per channel to keep the things simple as Dmitry Nizhegorodov's design.

I know this is a dangerous task for a newbie, but I have the expert help of an engineer with lots of experience. What fun do we have if we don't take risks?

I have been looking at all the designs you've post, and all of them seem amazing.
Please, need more advice on transformer selection. I have looked at EDCOR in USA but don't really know what to look for, I send them a message. But it would be great if some one can point me to the right OPT and PT.

I would like to include the option to use zero feedback or some feedback (-3dB, -6dB) with a toggle switch.
  Reply With Quote
Old 1st May 2013, 01:55 AM   #10
diyAudio Member
 
FullRangeMan's Avatar
 
Join Date: Aug 2009
Location: Brazil
Sowter can made a great sound OPT for 600 or 1K Ohms primary, but it is more expensive than EDCOR.
Brian Sowter is very friendly on custom orders.
SOWTER AUDIO TRANSFORMERS

EDCOR is inexpensive, but not C core, seems E I laminated, 25W only, Primary are 300, 600 ohms or more:
EDCOR - CXSE25-8-600

Also there is Ogonovski, price is good, 600 ohms, 50W, C core:
Ogonowski.eu - profesjonalne transformatry do wzmacniaczy lampowych
__________________
>Never go to a psychiatrist, adopt a cat or dog from the streets. On the streets pets live only two years average.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Set of newbie questions... bega_83 Car Audio 52 12th June 2011 08:03 PM
6C33C-EB / 6C33C-EV extended life ? ger56 Tubes / Valves 2 14th October 2007 05:54 PM
Good SET for newbie Jimmy_The_Clown Tubes / Valves 3 5th November 2004 06:44 AM
SET kit for newbie Grahamt Tubes / Valves 9 7th June 2004 02:22 PM
Newbie wants to build first set of speakers tacomaboy Multi-Way 15 14th January 2004 02:36 AM


New To Site? Need Help?

All times are GMT. The time now is 07:49 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2