7189 SHERWOOD by Philips – Heerlen 1963 – Gray Plates – rx4 – Matched Quad – Tested 100% - Made in HOLLAND
Description:
This matched quartet of 7189 Sherwood by Philips , produced in Heerlen (Holland) in 1963 , belongs to the prestigious line made by Philips for Sherwood, one of the most reliable and musical combinations of the time.
This is the gray plates variant with factory coding rX4 , one of the most recognizable signatures of Heerlen productions from the early 60s, known for its stability, build quality and high-level sound reproduction.
The set was selected in our laboratory as a Matched Quad , with coherent electrical behavior and uniform timbre across all specimens. Bench testing confirmed 100% performance, with solid output, excellent linearity, and perfect operational stability.
Sound Characteristics
The 1963 Philips Heerlen 7189s are renowned for their combination of power, musicality and refinement.
The presentation is bright, defined and rich in micro-detail, with a tonal balance that places them among the best European interpretations of the EL84/7189 family.
Bass
Tight, fast, and compact. The low end is precise and controlled, without any bloat, with a powerful yet balanced response.
Medium
The strong point of Heerlen's production. Airy, transparent mids, rich in harmonics , with realistic and natural voices. Excellent performance on acoustic instruments, jazz, and vocal music.
High
Bright, silky, and well-extended. The highs are defined and fluid, without harshness, with a finesse typical of vintage Philips EL84s.
Dynamics
Lively, responsive, with excellent control at high volume.
The response is clean, stable, with great ability to follow transients and an energetic output without unwanted compression.
Soundstage
Wide, three-dimensional soundstage, with clear separation of musical lines. Excellent focus and depth, with a solid, well-layered image.
🎧 Use in Hi-Fi Stereo Amplifiers
Perfect for amplifiers:
- Sherwood, Fisher and Scott of the time,
- European amplifiers requiring 7189 for higher voltages,
- systems where clarity, naturalness and dynamics are desired.
The quartet guarantees:
- uniform timbre,
- remarkable thermal stability,
- higher headroom than common EL84s.
Ideal for jazz, vocal, classical, fusion and high definition listening.
🎸 Use in Music Amplifiers
In music, the 7189 is highly regarded in vintage high-voltage amps such as:
- Gibson GA-series,
- American amplifiers with hot cathode bias,
- boutique projects requiring more robustness than standard EL84s.
They offer:
- progressive and musical distortion,
- great control over harmonics,
- wider and cleaner headroom.
🎯 Note for audiophiles and technicians
This Matched Quad Heerlen 1963 rX4 features:
- careful selection for uniform behavior,
- 100% test,
- operational stability and silence,
- high-end historic Philips building,
- Perfect compatibility with vintage devices that require real 7189s, not modern equivalents.
An ideal set for restoration, upgrade or use in high precision hi-fi amplifiers.
Test Results:
Valve tested on AMPLITREX AT-1000 Tube Tester:
- Test Conditions: Va = 250V, Vg2 = 250V, Vg = -7.3V
- Average 100%: Gm = 11.3 ; Ia = 48 mA
- Test Result: VERY STRONG
Valve 1: Gm = 11.2 ; Ia = 48.4 mA
Valve 2: Gm = 11.0 ; Ia = 48.0 mA
Valve 3: Gm = 11.0 ; Ia = 48.0 mA
Valve 4: Gm = 11.4 ; Ia = 49.4 mA
Additional Tests Performed:
- Microphonics: Low. Tested and approved for use in hi-fi and guitar amplifiers.
- Output Quality: Excellent – Very strong and stable output, no fluctuations.
- Short circuits and GAS: Absent.
Conditions:
- Condition: Vintage tubes - Tested and in perfect working order. Shipped in our custom box for optimal protection.
- Functionality: Fully functional.
- Aesthetic condition: Very good – Clearly legible writing with minor signs of wear, no obvious defects. See photos for details.
Manufacturing Code:
- rx4 Δ3A3 → rxx indicates a 7189 with the sequential progression of x, where the increment of x indicates the production changes - Δ3A3 Δ → Heerlen (Netherlands), 3 (out of four digits) → 1963 - A → January - 3 → 3rd week of the month
- rx4 Δ3A2 → rxx indicates a 7189 with the sequential progression of x, where the increment of x indicates the production changes - Δ3A3 Δ → Heerlen (Netherlands), 3 (out of four digits) → 1963 - A → January - 2 → 2nd week of the month
Find out why our valves are different →