Replacement Valve Kit for Marshall JCM900 SL-X 50W (3 x ECC83 1 x Balanced ECC83 2 x Matched EL34)

Replacement JJ valve kit for Marshall JCM900 SL-X 50w EL34 amplifier


Price Includes Free UK Delivery

498 in stock

SKU: AMPKIT422 Category:

All single valves, matched pairs and matched quads are fully tested in our warehouse before dispatch. These valves will guarantee awesome tone and amazing power. You WILL hear the difference. So get your amp sounding better than ever. Order your replacement valves today.


Need a replacement valve kit for Marshall JCM900 SL-X 50W EL34 amplifiers?

This is the EL34 replacement valve kit for Marshall JCM900 SL-X 50W head. It will get your amplifier sounding better than ever. These superior quality valves will give you a significant upgrade in both tone and power. The best value for money amplifier valves on the market today. This superb valve kit comprises:

  • 3 x Premium Grade JJ ECC83 preamp valves (also called 12AX7).
  • 1 x Premium Grade JJ Balanced ECC83 for the phase splitter position (V4).
  • 2 x Premium Grade JJ matched EL34 power valves/power tubes. 

We always recommend JJ valves for the  Marshall JCM900 SL-X 50W head. This is because they offer a superb tone at a very attractive price. We think these are the best valves/tubes for this amplifier. You can order these amplifier valves singly or as matched pairs but it is always recommended that you change all your valves at the same time if you possibly can.

So treat yourself to a brand new set of gorgeous sounding JJ valves today. Restore the power and clarity to your guitar amplifier.

  1. Awesome tone. This is what matters most. The number one priority for any Marshall has to be the tone. Particularly so for this amazing amp. Warm, rich, fat and juicy are the words that best describe the sound from these valves.
  2. Sustained valve/tube power to make the most of every stage in the amplifier chain. It is the balance between volume and tone that distinguishes a great valve from a mediocre valve.
  3. Long valve/tube life.  Guitar amps by their very nature have to be built to take a lot of knocks. This is also important when it comes to the amplifier valves themselves.

Do you have any questions about this valve kit? 

If you have any questions about replacing your valves please drop us an email. We have more than 30 years experience so we are sure we can help.

We tend to get asked the same questions most weeks so we have a very useful FAQ section that will answer most questions. You will also find some very useful tips here on upgrading your tubes.

The best replacement valve kit for the Marshall JCM900 SL-X 50W head on the market. 

  • Every valve kit is carefully selected, fully tested and digitally matched before we ship to you.
  • We have a range of fast delivery options with full tracking and insurance. So order with total confidence.
  • Global delivery – we ship all over the world every single day.
About the amp:

This JCM900 SL-X was produced between 1993 and 1999. It came in two power versions, 50 watts and 100 watts. It also came with two different power valve sets so you could either choose the EL34 or the 5881 depending on your taste. This is the Slash version of the JCM-900 lead amplifier and you will note that has an extra valve in the pre-amp section. There are two foot-switchable channels with independent volume controls.

  • Extra ECC83 (also called a 12AX7) valve in the pre-amp.
  • Pre-amp volume control and Gain sensitivity.
  • Series Effects loop.
  • Direct recording Line Out.
  • Fail-safe circuit to keep the amp running in the event of a valve failure.
  • Dimensions: 750 x 310 x 220 mm.
  • Weight: 18.4 Kg.

Tubes for sale for Marshall JCM900 SL-X head. Our JJ tubes guarantee awesome tone and restore the power and clarity to your amp. All valves 100% guaranteed. Carefully matched and selected.

Additional information

Weight0.33 kg
Dimensions15 × 15 × 15 cm
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Replacement JJ valve kit for Marshall JCM900 SL-X 50w EL34 amplifier

Replacement Valve Kit for Marshall JCM900 SL-X 50W (3 x ECC83 1 x Balanced ECC83 2 x Matched EL34)