UralTone 18W guitar tube amp - DIY kit

In 1964, Marshall copied the Watkins Dominator circuit and launched the Marshall 1974X amplifier. An 18 W EL84 pair, two channels, and a fantastic tremolo. The 1x12" combo produced enough volume for rehearsals and small gigs. Models 1958 (2x10" combo) and 1973 (2x12" combo) were also available.

The 18W has already been one of the most popular tube amplifier DIY projects among hobbyists for a couple of decades. And for good reason. The circuit is simple and easy to get working well. The sound represents a great British amplifier tradition. There is plenty of dynamics, the breakup is beautiful and controllable. The power is not excessive, but just about right for rock band rehearsals or small gigs.

Circuit

The UralTone 18W power section is a traditional EL84 power amp that compresses especially beautifully, offering sparkling highs and gradually crumbling into harmonically rich overdrive when driven hard.

The Normal channel features volume and tone controls.

The Tremolo channel includes a nowadays fairly rare tremolo circuit as well as volume and tone controls.

The original British versions used an EZ81 rectifier tube, but because availability is sometimes challenging nowadays, we have replaced it with an octal-based 5C4 / 5Y3 rectifier, which is still widely available at a reasonable price.

The whole unit is built into an aluminum chassis matching the dimensions of a JTM45 / 18W, meaning readily available JTM45 head and combo cabinets can also be used with the 18W.

Tubes

The power stage uses two EL84 tubes producing over 15 W in a push-pull configuration. The power section also directly supports Russian NOS 6P14P series tubes. Mad scientists may also experiment with NOS 6P15P and 6P43P tubes, as well as American 5763 tubes with socket rewiring.

The preamp and tremolo sections use a total of three 12AX7 / ECC83 / 7025 tubes.

You can also try lower gain 12AT7 or 5751 tubes. With a minor socket wiring modification, affordable NOS 6N2P tubes can also be used in the preamp, and these still seem plentiful worldwide.

The rectifier is a NOS 5C4 tube, roughly equivalent to a hybrid of a 5Y3 and GZ34. It can be replaced with a 5Y3, 5AR4/GZ34, or a solid-state rectifier.

Components

The components in the UralTone 18W kit are top quality throughout. We see no sense in saving on component prices, even if it raises the kit price by tens or hundreds of euros. Quality can be seen and heard.

Features

• 18 W EL84 push-pull power section
• Two channels: Normal and Tremolo
• Tubes: 2x EL84, 3x 12AX7 / ECC83 / 7025, 5C4
• Can be adapted to work with 6P14P, 6P15P, 6P43P, and 5763 tubes
• JTM45-sized chassis and cabinet compatibility
• Includes all required parts to build the amplifier

Kit instructions

Instructions for building the kit can be found here:

UralTone 18W kit illustrated instructions

You can also download the layout image, parts list, and other required documents from the instruction page. In some cases, the schematic is delivered separately.

Browse through the instructions beforehand to see what the building process is like and what kind of guidance is available. The parts list shows the components included in the kit at the time of sale.

We do not include printed instructions with the package.

Links to related products

JTM45 / 18W combo and head cabinets

Speakers

What does the package include?

The package includes all the necessary parts to assemble a working amplifier. The wooden cabinet is sold separately or can be made yourself.

How long does assembly take?

An experienced builder can assemble the kit in a day, while a beginner may need 2–3 days.

Who is this kit suitable for?

Anyone who appreciates great guitar tones and enjoys working with their hands. Also for those who want boutique quality but whose budget does not stretch to high-end boutique gear. Boutique amplifiers include costs for design, marketing (branding), assembly (if made in Western countries), etc. Many of these costs are eliminated in DIY kits.

What value do you get for your money?

A carefully assembled amplifier from our kits matches the quality of the most expensive boutique devices. The parts are top-notch and the devices are carefully designed. The price also includes unlimited technical support via email or our support site. With us, the customer is never left alone!

What kind of tools do you need to build this kit?

Basic tools are enough, but especially beginners should invest in reasonable quality.

Especially the soldering station and solder must be good enough to ensure proper solder joints. Always buy your soldering station from a knowledgeable electronics retailer that can help you choose the right one for this kind of work.

We have assembled a tool kit for beginners that makes building easy and will take you far in the hobby. You can choose the tools you want from the package:

BEGINNER’S SOLDERING TOOL KIT

In addition to this, you basically only need screwdrivers. If you are unsure whether your current soldering station (perhaps inherited from your grandfather) is sufficient, feel free to contact us and we will help determine whether it is suitable to get started!

How can I get support if I have questions I cannot find answers to?

A properly built device according to the instructions will work. So always read the instructions carefully. In problem situations, read through this article and follow its instructions:

DIY tube amplifier troubleshooting

If something still concerns you, you can contact us via email. Unlimited technical support via email is always included in the price. Please note that we cannot provide support by phone or in-store, because our technical support staff do not work in the store or behind our phone numbers.

WARNING: Building guitar gear is highly addictive!

NOTE: Component deliveries in the kit may differ from the components shown in model images due to component availability.