Circuit breakdown/getting started amp building

[gybe!]

I have toyed with amp building forever and currently am in a position to do so, but I am trying to chart my best path so am looking for advice/feedback from those that have done it before.

I have exposure to basic circuits (from undergrad physics courses, not EE; have done some basic troubleshooting beyond that), can follow a schematic generally, can solder, have built a few pedal kits, but am lacking the actual connection and understanding of the practical application of what is happening at a circuit to the impact. Said another way, I built some pedals but that was assembly and I couldn’t tell you what any of it did…

Is there any resource that goes through a circuit, of say a Plexi or the like, and actually addresses what is going on from a practical level? What is a slope resistor and what does it do? What is the impact of this coupling cap? Etc?

I am hesitant to just buy and assemble a kit as I’m weary of not actually learning much. I also don’t particularly want to start at the age old recommendation of an AX84 as I don’t find that interesting and recognize I won’t be as motivated to complete it…

 

[fusedbrain]

This might help:

https://www.ampbooks.com/mobile/classic-circuits/

I'm posting this from my phone, so that might explain the "mobile" in the link I copied/ pasted.
Or just Google ampbooks.com

Maybe have a look at the tutorials there as well.


This site is also good:
https://www.valvewizard.co.uk/

 

[ChurchHill]

There were a few that helped me get a grip on what's going on inside that magic black box. Can't say I agree with everything in all of these, but they did help build a foundation of understanding. I'm no expert, though.

Aspen Pittman - The Tube Amp Book
Kevin O'Connor - The Ultimate Tone Series (6 volumes, but 1-3 are the ones I remember most)
Gerald Weber - Desktop Reference of Hip Vintage Guitar Amps, Tube Guitar Amplifier Essentials, All About Vacuum Tube Guitar Amplifiers

For eye-watering analysis, check out Richard Kuehnel. His book on the 5F6A Bassman circuit isn't far removed from a Plexi.

Many, many others...

 

[manfifi]

If you really want to understand the circuits, check out Merlin Blencowe's books (Designing Tube Preamps for Guitar and Bass). It's probably the best modern explanation of guitar preamp stages

Tutuapp​

 

[CPGearHead]

I just completed a MOD 102+ build and learned volumes about tube amps from it! I guess it depends how much you want to answer the "why" questions when building it. Why did they choose that, what's that cap doing.

Are you a guitar player? If so, what sound/tone are you desiring. That's how you get on the road to find out

 

[Toneboner]

Uncle Doug vids on yt and Rob Robinette are great freely available resources.

https://robrobinette.com/How_the_Marshall_JCM800_Works.htm

 

[Toneboner]

Came across this recently too:

https://ampgarage.com/forum/viewtopic.php?t=38147

 

[MadAsAHatter]

Uncle Doug vids on yt and Rob Robinette are great freely available resources.

https://robrobinette.com/How_the_Marshall_JCM800_Works.htm

100% this. Both great resources. I'm not to far ahead of where the OP is. I have a couple builds under my belt and am about to start my next one. Those two resources really helped me get started in understanding things beyond just copying a layout.

I've also found D-Lab very helpful.
https://www.youtube.com/@d-labelectronics

Another great resource is Jason/Headfirst YouTube channel. Lots of great info on Marshall circuits & mods there.
https://www.youtube.com/@HeadfirstAmps

I've heard good things about is The Ultimate Tone book series by Kevin O'Conner, but haven't gotten them myself yet. They're a bit expensive, especially if you want the whole series. Most people say to start with Vol 3. My understanding is it goes over more practical aspects and has explanations, schematics and layouts for a bunch of vintage circuits.
https://londonpower.com/electronics/all-11-books/

Our own @TotallyRadGuitars has some in-depth amp review videos where he'll talk a bit about the circuit. That helped my understand the signal path and how it related to tone & settings for the given amp.
https://www.youtube.com/@totallyradguitars959

 

[gybe!]

My wife got me the rosamp slo kit for my birthday, sadly been too damn busy fixing my race car that I seem to enjoy breaking all too frequently to get started on it yet

 

[MadAsAHatter]

My wife got me the rosamp slo kit for my birthday, sadly been too damn busy fixing my race car that I seem to enjoy breaking all too frequently to get started on it yet

Those kits look to be pretty solid. I would have gotten one, but had already bough a Sweet Lucy Overdrive (SLO) PCB and transformers from Sirius before I came across Rosamp.

This guy built one of the Rosamp SLO kits. I watched it a while back so don't remember what all he talked about for the build. Posting the video in case there's something in there that might help you out.