New guy question: what do all these things do??

[oguinn]

While I’m waiting for my SEX and Quickie to ship, I’ve been trying to learn everything I can about the amp I’ll be assembling. I’ve printed off and skimmed through the instructions, but one thing I’m still not clear on is what role each piece plays.

Is there an explainer that outlines what each major part is l, what it actually does, and why it’s in the circuit where it is? e.g., “this is the output tube, it performs x, y, and z functions and is here because 1, 2, and 3 reasons”

Even if there’s something that is generic to tube amplifiers and not necessarily specific to Bottlehead gear, I’m really curious about this stuff and not totally clear where to start.

[Paul Birkeland]

You can check out Valve Amplifiers by Morgan Jones.

[oguinn]

Thanks, PB. It's on order.

Another question I have is whether I can swap in any tubes that are 6FJ7, or if I need to look for any particular characteristics of that type of tube. I'm less worried about tube rolling at this point and more eager to make sure I have spares for the future. I picked up a couple of Raytheon 6FJ7s and Tung-Sol 3S4s (for the Quickie) for cheap, so I'm not heartbroken if I accidentally got something wrong.

[Paul Birkeland]

Any tube that says "6FJ7" on the glass will do the job nicely.  It's also really handy that there a very few variations on the internal construction, so matching pairs is much easier than matching random pairs of 3S4s or 12AU7s. 

[oguinn]

Good deal. Thanks for the information!