Tube cross-reference
5591 alternatives, equivalents, and replacements
Review exact electrical variations and directional substitutions recorded for the 5591 voltage pentode - high frequency (single). Compare core specifications and verify every restriction before using a replacement.
Exact variations of 5591
These designations belong to the same electrical variation group. Their names may differ because of international standards, manufacturing tolerances, or materials, but they are recorded as electrically equivalent—not merely substitutes.
403B Voltage Pentode
- Base
- E7-1
- Socket
- B7G
- Base pins
- 7
- Sections
- 1
- Heater voltage
- 6.3 V
- Heater current
- 0.15 A
Replacement tubes for 5591
The following tubes are recorded as possible replacements for 5591. This direction does not establish that 5591 can replace them.
Voltage Pentode
The database records 403B as a possible replacement for5591.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode |
| Construction | Pentode | Pentode |
| Base | E7-1 | E7-1 |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.15 A |
Voltage Pentode - High Frequency (single)
The database records DP61 as a possible replacement for5591.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode - High Frequency (single) |
| Construction | Pentode | Pentode |
| Base | E7-1 | Not recorded |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.175 A |
Voltage Pentode
The database records E95F as a possible replacement for5591.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode |
| Construction | Pentode | Pentode |
| Base | E7-1 | Not recorded |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.175 A |
Voltage Pentode - Sharp Cutoff (single)
The database records EF95 as a possible replacement for5591.
No special restrictions are recorded for this substitution.
| Specification | Original tube | Replacement |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | E7-1 | 7BD |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.175 A |
Where 5591 can be used as the replacement
In these recorded relationships, 5591 is the replacement tube. The listed original tubes are not automatically suitable as replacements for 5591.
Voltage Pentode
The database records 5591 as a possible replacement for403B.
No special restrictions are recorded for this substitution.
| Specification | 5591 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode |
| Construction | Pentode | Pentode |
| Base | E7-1 | E7-1 |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.15 A |
Voltage Pentode - Sharp Cutoff (single)
The database records 5591 as a possible replacement for6AK5.
- Parallel heater circuits only
| Specification | 5591 replacement | Original tube |
|---|---|---|
| Tube type | Voltage Pentode - High Frequency (single) | Voltage Pentode - Sharp Cutoff (single) |
| Construction | Pentode | Pentode |
| Base | E7-1 | 7BD |
| Socket | B7G | B7G |
| Base pins | 7 | 7 |
| Sections | 1 | 1 |
| Heater voltage | 6.3 V | 6.3 V |
| Heater current | 0.15 A | 0.175 A |
Verify before substituting
Matching a base or heater voltage is not enough to prove that two tubes are interchangeable. Check pin connections, heater current, maximum ratings, bias requirements, warm-up behavior, and the equipment manufacturer’s service documentation before making a substitution.
View the complete 5591 specifications →