sweept tubes for simple Se recommendation?

dubdub · 29th March 2009, 11:41 PM

Hi Everyone

I have finished putting together my Simple SE with jj el34s and have been enjoying the sound but now Im keen to try out different tubes without breaking the bank-sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?

POWER TRANSFORMER:
EDCOR 375-0-375 @ 175mA with taps at 50V @ 50mA, 6.3V CT @ 6A and 5V CT @ 3A.

OUTPUT TRANSFORMER:

TRANSENDAR 5K with ul tap

(pics comming soon one I figure out how-does anyone know the code to link to pictures @ filckr etc?)

Thanks everyone (and thanks Tubelab for the great project!)

whitelabrat · 30th March 2009, 12:16 AM

Phillips- ECG 6BG6GA. You'll need an adapter, but they're cheap, sound good (to me) and take a beating.

Miles Prower · 30th March 2009, 06:48 AM

Quote:

Originally posted by dubdub
sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?

It isn't easy to use horizontal deflection types in single ended circuits. The most linear portion of the characteristic lies well within red plate territory. They work much better in PP, Class AB designs.

The 6BG6 that whitelabrat mentioned is basically an 807 with an octal base, which, in turn, is a 6L6. Other than that one, I'd forget about that.

Alastair E · 30th March 2009, 11:40 AM

Quote:

Originally posted by dubdub
Hi Everyone

I have finished putting together my Simple SE with jj el34s and have been enjoying the sound but now Im keen to try out different tubes without breaking the bank-sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs?

POWER TRANSFORMER:
EDCOR 375-0-375 @ 175mA with taps at 50V @ 50mA, 6.3V CT @ 6A and 5V CT @ 3A.

OUTPUT TRANSFORMER:

TRANSENDAR 5K with ul tap

(pics comming soon one I figure out how-does anyone know the code to link to pictures @ filckr etc?)

Thanks everyone (and thanks Tubelab for the great project!)

Line-Output bottles dont particularly work well in S.E type designs. For the 'Simple-SE' I would choose a proper audio valve, Loads of types to choose from that wont break the bank!

Sweep/Line-O/P work well in P-P and especially Screen-Drive but nearly all of them suffer from low screen max voltage/dissipation issues when run in S.E modes.....

CarlyBoy · 30th March 2009, 02:15 PM

How 'bout Bob Danielak's screen driven 6KG6 project:

www.geocities.com/bobdanielak/technoteNo33.html

Your output trafo looks about right. I'm sure you could use your power trafo as well, but with tube rectification to get the voltage down a bit.

dubdub · 30th March 2009, 09:41 PM

Thanks for the advice everyone- obviously not a good idea to use these type of tubes! to be honest, I am looking for some dirt cheep nos tubes to experiment with simple SE, any suggestions appricated-thanks for the advice still getting my head around tube gear

w5jag · 31st March 2009, 01:25 AM

The 6BG6's that WB0SND sells might be the easiest, since he sells adapters to convert them to the 7AC pinout, they were intended to run at 6L6/807 like voltages to begin with, and some Simple SE users already have experience with these tubes. They would probably sound the best, since they really aren't what I consider sweep tubes.

So many sweep tubes are high perveance, meaning they were meant to run at lower plate voltages and higher cathode currents. When you run them at higher voltages, you wind up with large cathode voltages and a lot of heat dissipated in the cathode resistors; you would likely need 100 volt cathode bypass caps, and 10 watt resistors to accomodate sweeps. You also need to accomodate the plate caps, and they may have a different overall gain than traditional audio tubes.

6DQ6 and 6BQ6 have the right pin out (but you still need the plate cap connection) to plug in the Simple SE, but all of the above "gotchas" apply. I am listening to 6BQ6GTB's in my Simple SE right now, but I have a dual secondary voltage power transformer in my amp, making it easier to run the sweeps and little beam tetrodes and power pentodes. I am running the 6BQ6GTB's in triode at about 220 volts and 70 ma / tube, or about 14 watts total dissipation. They don't sound bad, but I consider tubes like these in this application to be kind of a novelty. Somewhere on the site is a pic of my Simple SE with 6DQ6's in it.

George has made some posts on these tubes in the Simple SE, and others probably know more about it than I, but that is my $0.02 worth.

Win W5JAG

29th March 2009, 11:41 PM	#1
dubdub diyAudio Member Join Date: Jan 2008	sweept tubes for simple Se recommendation? Hi Everyone I have finished putting together my Simple SE with jj el34s and have been enjoying the sound but now Im keen to try out different tubes without breaking the bank-sweep tubes look very inexpensive but can anyone recommend types that can be used with in the following specs? POWER TRANSFORMER: EDCOR 375-0-375 @ 175mA with taps at 50V @ 50mA, 6.3V CT @ 6A and 5V CT @ 3A. OUTPUT TRANSFORMER: TRANSENDAR 5K with ul tap (pics comming soon one I figure out how-does anyone know the code to link to pictures @ filckr etc?) Thanks everyone (and thanks Tubelab for the great project!)

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Simple, SIMPLE Digital volume control	-_nando-_	Digital Source	5	21st December 2006 01:20 PM
Research on tubes and circuits simple circuits	Cazcotty	Tubes / Valves	6	16th June 2006 12:50 PM
I need a simple schematic with 6J1P tubes	kosmin227	Tubes / Valves	3	19th December 2005 11:30 PM
simple matching philosophy on tubes..	GeirW	Tubes / Valves	1	17th February 2004 07:20 AM
a simple preamp with 5687 tubes	karma	Tubes / Valves	3	23rd April 2003 08:44 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	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

30th March 2009, 12:16 AM	#2
whitelabrat diyAudio Member Join Date: Dec 2006 Location: Maryland	Phillips- ECG 6BG6GA. You'll need an adapter, but they're cheap, sound good (to me) and take a beating.

30th March 2009, 02:15 PM	#5
CarlyBoy diyAudio Member Join Date: Aug 2006	How 'bout Bob Danielak's screen driven 6KG6 project: www.geocities.com/bobdanielak/technoteNo33.html Your output trafo looks about right. I'm sure you could use your power trafo as well, but with tube rectification to get the voltage down a bit.

30th March 2009, 09:41 PM	#6
dubdub diyAudio Member Join Date: Jan 2008	Thanks for the advice everyone- obviously not a good idea to use these type of tubes! to be honest, I am looking for some dirt cheep nos tubes to experiment with simple SE, any suggestions appricated-thanks for the advice still getting my head around tube gear

31st March 2009, 01:25 AM	#7
w5jag diyAudio Member Join Date: Feb 2007 Location: Arkansas	The 6BG6's that WB0SND sells might be the easiest, since he sells adapters to convert them to the 7AC pinout, they were intended to run at 6L6/807 like voltages to begin with, and some Simple SE users already have experience with these tubes. They would probably sound the best, since they really aren't what I consider sweep tubes. So many sweep tubes are high perveance, meaning they were meant to run at lower plate voltages and higher cathode currents. When you run them at higher voltages, you wind up with large cathode voltages and a lot of heat dissipated in the cathode resistors; you would likely need 100 volt cathode bypass caps, and 10 watt resistors to accomodate sweeps. You also need to accomodate the plate caps, and they may have a different overall gain than traditional audio tubes. 6DQ6 and 6BQ6 have the right pin out (but you still need the plate cap connection) to plug in the Simple SE, but all of the above "gotchas" apply. I am listening to 6BQ6GTB's in my Simple SE right now, but I have a dual secondary voltage power transformer in my amp, making it easier to run the sweeps and little beam tetrodes and power pentodes. I am running the 6BQ6GTB's in triode at about 220 volts and 70 ma / tube, or about 14 watts total dissipation. They don't sound bad, but I consider tubes like these in this application to be kind of a novelty. Somewhere on the site is a pic of my Simple SE with 6DQ6's in it. George has made some posts on these tubes in the Simple SE, and others probably know more about it than I, but that is my $0.02 worth. Win W5JAG