|
Tube DIY Asylum: $100 School Amp Project Problems by LeBob Do It Yourself (DIY) paradise for tube and SET project builders. |
For Sale Ads |
165.121.239.86
We have approval from our school director to show kids how to build tube amps. Unfortunately, the liability involved in the project can go beyond the school to include the individual faculty involved. We are now trying to find an alternative to high/lethal voltages.I have been looking into low voltage tubes that can be operated from a wall-wart: subminiature, 6gm8, and old battery operated radio tubes. Studying the plate curves of some different tubes, I was thinking I might be able to make a tube amplifier with voltages as low as 50 volts with about the same amount of current or less than tubes that run at 250 volts. I am thinking this could be a bit safer for students and eliminate some of the fear of liability for the faculty. I spoke with the students about this and headphone amps and tube driven solid state amps did not interest them. Unfortunately, they have listened to a few of my DIY and vintage tube systems and have it set in their minds (I sort of helped) that they want to build tube amps.
I am thinking a one or two watt amp could make a very satisfying computer sound system. Maybe a 6gm8 or 6922 driving something like a 12b4a or 1ag4. I was also thinking of a low voltage dual triode driver tube run parallel or in push-pull. I am thinking that if I could get at least one watt or more from this project it would still be good for students.
I have been able to find little information on the web about low-voltage output tubes or their use in amplifiers. Maybe their are some tubes that are still fairly linear down around 50V or less that could be used for audio output. Any advice in this area would be very helpful. I have about a week to figure something out or else I will probably have to cancel the class.
Thanks in advance,
Orren
This post is made possible by the generous support of people like you and our sponsors:
Topic - $100 School Amp Project Problems - LeBob 13:16:32 02/21/04 ( 18)
- I tried I can't get more than 0.33W at 70V's??? - Gordon Rankin 09:23:24 02/27/04 ( 3)
- Re: I tried I can't get more than 0.33W at 70V's??? - Eli Duttman 01:48:33 02/28/04 ( 2)
- Eli I am not getting anything close to 5W's - Gordon Rankin 15:15:13 02/28/04 ( 1)
- Re: Eli I am not getting anything close to 5W's - Eli Duttman 17:30:01 02/28/04 ( 0)
Go 120V heater amp wtih isolation transformer for safety ! - cheap-Jack 07:51:26 02/23/04 ( 0)
Try Russian pass valves (6C19(Pi), 6C41(C)) - mb-de 05:10:50 02/23/04 ( 0)
Re: $100 School Amp Project Problems - steven oda 11:37:41 02/22/04 ( 0)
Re: $100 School Amp Project Problems - PrairiePete 20:02:03 02/21/04 ( 2)
- dare I say gain clones - kloss 06:51:13 02/22/04 ( 0)
Re: $100 School Amp Project Problems - PrairiePete 20:04:31 02/21/04 ( 0)
Re: $100 School Amp Project Problems - Eli Duttman 15:09:41 02/21/04 ( 4)
- Re: $100 School Amp Project Problems - LeBob 20:58:36 02/21/04 ( 3)
- Re: $100 School Amp Project Problems - Eli Duttman 22:15:34 02/21/04 ( 2)
- Re: $100 School Amp Project Problems - LeBob 07:14:59 02/22/04 ( 1)
- Re: $100 School Amp Project Problems - Eli Duttman 13:18:40 02/22/04 ( 0)
Re: $100 School Amp Project Problems - Sector-7G 14:29:22 02/21/04 ( 0)
Re: $100 School Amp Project Problems - throbbinnut 13:50:05 02/21/04 ( 0)
Re: $100 School Amp Project Problems - Pär 13:49:16 02/21/04 ( 0)