blackstar studio 20

Blackstar HT Studio 20

Valves for Blackstar HT Studio 20 amplifier.

The Blackstar HT Studio 20 and Studio 20H (the head version) amplifier use:

  • 2 x ECC83 (also called 12AX7) preamp valves.
  • 2 x EL34 matched power valves/power tubes.

Over time your valves slowly lose both their tone and their power. Replace them on a regular basis to maintain the full tone of your amp. We always recommend JJ valves for Blackstar Studio 20 amplifier. This is because they guarantee awesome tone and power. They also give you long life – all at a very competitive price.

It’s a hybrid amp and the phase inverter is solid state rather than valve.

Note: This amp is both cathode-biased AND fixed bias (which is why there is a bias adjustment screw inside). Now that is a bit confusing but this is what Blackstar say:

“The Blackstar HT-20 uses a combination of cathode bias, and fixed bias in its output stage. It also has a bias balance feature, to minimise background hum caused by slight valve manufacturing tolerance imbalance”.

Order your valves for Blackstar HT Studio 20 below and hear the difference.

So bring back the power and sparkle to your guitar amplifier. Treat yourself, and your amp, to a brand new set of valves today. 

  • All of our valve kits are carefully chosen, fully tested and digitally matched before we ship them to you.
  • These valves are a significant upgrade to the valves currently in your amp.
  • Fast delivery options. Fully tracked to your doorstep so you can order with confidence.
  • We ship around the world every single day.

Replace the Valves for Blackstar HT Studio 20 amplifier.

If you have any questions about replacing the valves for Blackstar HT Studio 20 amplifier please do not hesitate to drop us an email and we will get straight back to you.

We have over 30 years of experience so we are always happy to help.

If you have never changed your valves before please take a look at our very helpful FAQ section before you contact us.

About the Blackstar HT Studio 20 and HT Studio 20H:

The HT Studio 20 combo is the big brother of our critically acclaimed HT-5 and offers huge versatility for home, rehearsal or studio use.
The carefully voiced preamp coupled with a cathode-biased EL34 power amp, provides the user with the ability to create wonderfully lush valve tones. The 12″ Celestion speaker certainly helps here as well.


  • 20 Watt valve (available as combo or head).
  • Valves/Tubes: 2 x ECC83 and  2 x EL34.
  • 12″ Celestion speaker on the combo version.
  • Digital reverb.
  • Speaker emulated output.
  • Finally, that cool vintage styling.

So order yours today and get your amplifier sounding better than ever.

Simply choose the complete replacement valve kit or the seperate valves for your amplifier below: