Detail 01
Quartet
Four tubes, all matched to each other. Sized for amps with four EL84 sockets, not two.
Product detailSKU #1274034469260
Groove TubesGold Series GT-EL84-S Matched Power Tubes Medium (4-7 GT Rating) Quartet
Sale
Independent shopping perspective
The Korena take
A matched quartet of EL84 power tubes for amps that run four of them. Replacement stock for a working amp, not a tone experiment.
Strong match
Who this is for
- Retubing a four-EL84 combo or head that has gone dull
- Amps needing a factory-matched set rather than mixed singles
- Players who want a known bias rating written on the box
Consider the trade-offs
When to look elsewhere
- Amps running EL34, 6L6 or 6V6 power tubes
- Anyone needing only one or two tubes
- Preamp tube replacement — these are power tubes
What matters in use
The specifications, translated
Catalog numbers tell only part of the story. These are the details most likely to change how this product feels, sounds, or fits into a setup.
Detail 02
Matched set
The tubes draw current within a close range of each other, so output stays even across the pair or quad.
Detail 03
Medium, 4-7 GT rating
Groove Tubes' own scale for where the tube sits between soft and stiff. Medium is the middle of that range.
Detail 04
EL84
Small nine-pin power tube. Fixes the amp family this fits — EL84 sockets only, no swapping with octal types.
Detail 05
Made in Slovakia
Single production source, so tubes across the set come from the same line.
Detail 06
$121 for four
Around $30 a tube, which is the going rate territory for matched EL84 sets rather than budget singles.
Final check
Know before you order
- 01Count your amp's power tube sockets first — a quartet is wasted on a two-tube amp
- 02Many EL84 amps are cathode-biased, but confirm whether yours needs a bias set
- 03No preamp tubes included; a full retube also needs 12AX7-type tubes
Product questions
Before you decide
Straight answers to the questions shoppers most often ask about this product.
01Do I need to rebias after installing these?
Depends on your amp. Cathode-biased EL84 amps generally self-adjust; fixed-bias designs need a bias check. Have a tech confirm if you are unsure.
02What does the 4-7 rating mean?
It is Groove Tubes' internal scale describing how the tube behaves in the middle of their range. Use it to order a comparable set next time.
03Can I use these in an EL34 amp?
No. EL84 is a nine-pin tube and EL34 is octal. The sockets are different and the amp is designed around one or the other.
04Are these matched to each other?
Yes, all four are matched as a set. Buying a quartet keeps output balanced across the power section.
Reference
Full specifications
The complete catalog record, organized around the decisions musicians make when comparing gear.
2 detailsBody & build
- Color
- Gold
- Country of Origin
- Slovakia
