Power Tube Resistors

[wattsup]

I'm totally new to all this and have what's probably a really basic question but here goes. On like the Bluesmaster layout, on the 6L6 tubes what are the 500 ohm and the 5k1 resistors called? I keep seeing terms like "grid stop resistors on the power tubes". And things like that. Which of those is the grid stop resistor and what is the other one called?

[sepulchre]

On the layout posted here the 5K1s are the grid stoppers on the power tubes and the 500Rs are the screen resistors.

Edit: Here's the schematic.

[wattsup]

On the layout posted here the 5K1s are the grid stoppers on the power tubes and the 500Rs are the screen resistors.

OK I think I understand what the grid stoppers are for. What are the screen resistors for?

[sepulchre]

The Screens need to be at a slight lower voltage than the Plates. You really need to understand how a Pentode tube works to get why. I'm not the best guy to explain it.

Here's a bit of an explanation. It's describing a far simpler amp but does contain the basics of tube amplification, and it covers triodes too (preamp tubes).

[wattsup]

Oh thanks! That ought to keep me busy for a bit.

[sepulchre]

For a more definitive source: http://www.valvewizard.co.uk/

The links on the left side of the page will give you a lot but his "Preamp" book is one of the best resources you can get for doing this.

[Structo]

That book is a very good reference book about preamps, but it is at a level assuming you know basic electronics.

Perhaps a better book for you would be Dave Hunter's book "Guitar Amplifier Handbook"

It talks about each stage in a vacuum tube guitar amp in a generally easy to understand fashion if you are a beginner.

Although I had electronics education in years past this was the first book I bought to reacquaint myself to tube amps.

Well worth the money.

http://www.amazon.com/Guitar-Amplifier- ... 428&sr=1-5

[wattsup]

That book is a very good reference book about preamps, but it is at a level assuming you know basic electronics.

Perhaps a better book for you would be Dave Hunter's book "Guitar Amplifier Handbook"

It talks about each stage in a vacuum tube guitar amp in a generally easy to understand fashion if you are a beginner.

Although I had electronics education in years past this was the first book I bought to reacquaint myself to tube amps.

Well worth the money.

http://www.amazon.com/Guitar-Amplifier- ... 428&sr=1-5

Gonna have to wait from amazon I spose. Temporarily out if stock but looks like a great read. Thanks Structo!