Need help with a tube amp project

[RayRay1132]

Ok, sorry if this seems like a dumb request (I'm more or less a beginner when it comes to amplification circuits), and I need help designing a simple tube amp. I have a basic understanding of how vacuum tubes work. If someone could help me with the simplest possible design for driving an 8ohm speaker. Any recommendations on relatively cheap, but good tubes. I also need help with a making a good power supply for it all. I'm also planning on building it open layout temporarily (just experimenting), so if anyone can find a good schematic that's not too complicated, that would be great. Thanks in advance -Ray.

 

[Nigel Goodwin]

No valve schematics are 'complicated' as they are crude and simple devices.

The main question is what you already have, what you're prepared to spend to buy parts, and what kind of spec you're looking for.

Expensive parts are mains transformer, output transformer, and the valves themselves - and 'possibly' a supply choke as well. None of those are cheap.

Assuming you just want a 'cheap' low power single ended amplifier?, then it's remarkably simple.

Here's a classic Mullard 3W design, which is also fairly high quality (in valve terms) - as always the main issues are transformers and decent valves. If you want something even simpler?, there are numerous simpler designs that are simpler but lower quality.

Mullard Single-Ended (SE) EL84 Tube Amplifier Schematic EL-84

The Mullard Single-Ended (SE) EL84 Tube Amplifier Schematic. The circuit uses and EF86 input stage.

diyaudioprojects.com

Have you considered just buying a cheap kit from China? - this will get you all the parts for less than you can source them.

 

[JimB]

Here's a classic Mullard 3W design,

Attachment?
JimB

 

[Nigel Goodwin]

Attachment?
JimB

It was a link, but I seem to have misplaced it

It's back now.

 

[Nigel Goodwin]

As an added example, with easily available parts, here's a recent one from RS Components Designspark pages:

How To Build a Valve Amplifier | Valve Amplifier Design & Diagram | DesignSpark

Building a brand new valve amplifier using the RH84 design and off-the-shelf components.

www.rs-online.com

Rather bizarrely that page only links to the next two?

Building a Valve Amplifier | Speaker Power Supply Circuit | DesignSpark

Building a brand new valve amplifier using the RH84 design and off-the-shelf components.

www.rs-online.com

Building a Valve Amplifier Part 5: Final Assembly

Building a brand new valve amplifier using the RH84 design and off-the-shelf components.

www.rs-online.com