Building a tube guitar amp step by step

[DaveMojo]

Hi All,

I am new to this Forum and I am new to Tube Amp.

I play guitar but mainly Organ and Fender Rhodes or Similar Clones such Crumar Seven and Crumar Mojo.

Lately it became important recording music and so far beside Leslie speaker on the rehearsl place only Keyboard amp were used for both Crumar Seven and Crumar Mojo as explained they are respectively an Organ and a Vintage piano that is a Rhodes clone.

Both instruments can sound fantastic on a guitar Tube amp and here is why I am here.

I have no experience at all with tube amps, never used one handmade. I had a Marshall Stack once but that was back in 98.

I want to built my first 18 Watts Guitar Tube Amp a plexi style seems what Jon lord was using a Marshall to attach my Organ and emulate what Jon was doing with his Hammond get that distorted sound. I know not easy to accomplish.

I am also enthusiastic to learn and I must start somewhere. Everywhere I read that is not something easy and can be dangerous due to high voltage and cannot really find a site that has a simple tube amp build to start with with simple instructions step by step.

So I would like to build a Combo (maybe not a plexi) something simple that is made by tubes and possibly provide that warm sound of tubes amp and get a distorted sound when playing load, maybe a 5 Watts or 10 Watts.

Is there anybody here that can really point me out to a project that I can follow easily and can point me out to where to buy parts amp kits with full instructions?

I cannot find anything and probably is the way it is not for people like me if you confirm so then I give up

:-)

Thanks

[jewishjay]

1st question: Do you have any experience with electronics and soldering?

If not... look for diy low voltage electronics projects to practice understanding and following schematics at safer voltage, and to practice soldering. You'll need to be really good at those two points before moving on. Gotta walk before you run.

[bmccowan]

A couple things. I agree with Jay to a degree. I agree with learning soldering skills. But I think you can learn those skills on a Hoffman Turret board. I suggest getting a Champ board with the turrets installed and the associated board components and some buss wire. And of course any tools you need. The soldering and assembly instructions are all right here on Doug's pages, and they are very good. Most beginner problems happen when people don't read any of the instructions, and or buy cheap boards elsewhere. Their frustrations can be found right here on the Forum, as well as Sluckey talking them in for a landing like the scenes from Airplane. None of this part is done with any electrical current applied to the circuit so the only dangers are burning your arm on the soldering iron, or leaving it on and burning the house down. In fact, none of the building is done with a powered circuit. That all comes when you start to test your build. For that you want to read the instructions a few times and carefully follow them. You especially need to understand how capacitors work so that you do not get zapped when you think all is safe.
I have read that people like the Trinity instructions for their kits - you can find them here: https://www.trinityamps.com/support/   I wish I had studied some documents like these and Doug's instructions before I started. I survived, but just barely.

[dwinstonwood]

Hoffman has amassed a great deal of information and how-to's on this page:
https://el34world.com/schematics.htm#Helpful%20info%20items

It's all written in easy to understand language for beginners. And, there are lots of illustrations and diagrams.
I would read through the links on that page. There's no complicated math or deep electronics theory, he simply explains how things work, and the right ways to do amp building.

FWIW, I built my first tube guitar amp last Spring in a thread on this forum (a Vox AC4). I got tons of help. Since then, I've built two more amps on this forum. When I chose to follow the expert advice here, and read Hoffman's info and how to's - often two or three times until I got it - I ended up with amazing working amps.

I say pick a basic, well-proven design, build it stock (you can always mod it later, after it works), and work slowly, paying attention to what people tell you to do. You'll have success!

[Mike_J]

+1 on a Champ build.

[vampwizzard]

Dave,

Welcome to the forum! If you're in the US, check out some of the kits Doug offers: https://hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&thispage=PartsListIndex.htm&ORDER_ID=!ORDERID!

Particularly, the 5F1 kit which is a fender champ. https://el34world.com/schematics.htm#Hoffman_5F1_Tweed_Champ

Typically the difficult part from there is sourcing the rest of the amp.. the cabinet, speaker, all the little pieces to make it a finished amp. While the Hoffman layout is superior in layout and components, the mojotone 5F1 kit would have everything together there to build one. There are other kit makers, we have seen some other folks here who have had a hard time with poor quality parts.

[d95err]

A Tweed Deluxe (5e3) or ”18 Watter” are also good places to start, if it’s a kit with good instructions.

It’s not really any harder to build those compared to a Champ. Just a few more components. Bit more money thrown away if it goes wrong though.

[bmccowan]

check out some of the kits Doug offers

I do not think Doug offers the transformers and the chassis any longer. But I would still not hesitate to purchase a turret board, pots, caps, resistors, jacks, etc. using the parts list he has up. And then source the chassis, trannies, etc from Mojo, Tube Depot, Weber, or other. I say this because of the problems some have recently had with poor quality turrets, and Doug is on top of that situation.

[Mike_J]

A Tweed Deluxe (5e3) or ”18 Watter” are also good places to start, if it’s a kit with good instructions.

It’s not really any harder to build those compared to a Champ. Just a few more components. Bit more money thrown away if it goes wrong though.

A tweed deluxe is also a great amp. How large are your venues? If you play some small places and want some overdrive then I would still start with a Champ although I really like my Tweed Deluxe build it is a lot of fun to play and sounds very good. I think I measured my Tweed Deluxe as about a 12 watt amp and it is surprising loud for a small amp which is why I mention the venue size issue.


I build and cover my own cabinets. For the tweed amps that were made from southern yellow pine I went to the extent of going to the fine woods shop and thumped all their yellow pine boards to see which rang the best. All the corners were finger jointed. Absolutely nutty thing to do but I do enjoy building my own cabinets. Now most of the cabinets I make are made from Baltic Birch plywood. I have a local supplier that will cut the plywood to dimension in return for me buying the plywood from him. Use biscuit joiner and long screws to join the sides with the top and bottom now and it seems to work well and doesn't require a lot of the tools I once had. A lot easier to buy the cabinet already made though. Depends on your skill level and how much of the amp you want to build yourself.


If you wanted to build a Champ with a single 12" eight ohm speaker rather than the 8" four ohm speaker the Champ came with then you would need a larger cabinet with a cutout for the champ chassis. Easy if you make it yourself. Best to get an output transformer with secondary taps for both four and eight ohm speakers in my opinion. A company called Magnetic Components made what in my opinion were very good transformers but they were a victim of Covid after almost 80 years but you can still get their transformers from suppliers while they last. Cabinet, transformers, chassis and speaker make up a significant portion of the cost of a build. Once you source those parts the rest is easy and can mostly be purchased from Doug.


Only reason I mentioned the 12" speaker is there is a much better selection of 12" than 8" speakers in my opinion. The original Champ that many records were recorded on had an eight inch speaker as I recall so a larger speaker is not a requirement.

[Sonny ReVerb]

This is a great forum, but I think AX84 is much better for beginners. The first amp I built was a P1-eXtreme. Read through the P1-eXtreme Theory Document until things start to make sense. It is a great resource for beginners with simplified explanations of the building blocks of a tube amp. You can find answers to many of your questions by reading through the FAQ on their site before asking your first question on a forum. When you're ready for your 18W build, come back here to work out the bugs. Welcome to the hobby!

[tubenit]

Here is a video on building a Fender Champ


How to Build a Tweed Champ 5F1 Step-by-Step (Upcoming LIVE Build Along) - YouTube



And we  have a forum member who has made a number of videos on do-it-yourself builds including a current one he is involved in.

Why don't you check one of those out?  Watching the video may be an excellent investment in time learning about the process and what is involved to be successful.

https://el34world.com/Forum/index.php?topic=26681.0

With respect, Tubenit

[kagliostro]

I knew I had some links, but until now I couldn't find them

I hope they can be of your interest

https://youtu.be/nclJ1_L4bgg

https://youtu.be/tHILcE6iEv4

https://youtu.be/0jl3lZV23LA

https://youtu.be/Ap3UTXRHytQ

https://youtu.be/5QQvGdwKxZ8

https://youtu.be/guOCc2zre8M

https://youtu.be/0EXOsC2Zqq0

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https://youtu.be/wpmjaymTWIs

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Shielded cable

https://youtu.be/E7Vj9bAV4R8?list=PLAppKXUgbBIt1vAo2N2vHvfw4HhV2hCp1


Franco