Philips N4512

The Philips N4512 (including variants like N4512/00 or rebranded as Maestro 4512 in some markets) is a mid-to-late 1970s flagship consumer stereo reel-to-reel tape recorder, produced approximately 1975–1979 (manufactured primarily in Austria by Philips Österreich). It was one of the top models in Philips' N45xx solid-state hi-fi series (often grouped with "Magno Control" family like N4506/N4520), emphasizing premium hi-fi performance, three-motor drive, three-head configuration, and wide frequency response. The N4512 was designed for serious home enthusiasts, offering excellent recording fidelity, low noise, and off-tape monitoring—often seen as a refined evolution of earlier N44xx/N45xx decks before the shift to cassettes dominated.

This was a 4-track (quarter-track) stereo machine with true stereo recording and playback in both directions, built-in stereo amplification (in integrated versions), and strong emphasis on audio quality (DIN 45500 hi-fi compliant with low-noise tape).

Key Technical Specifications

• Recording/Playback System — 4-track (quarter-track), 2-channel stereo/mono compatible; records and plays stereo on tracks 1-4 forward and 3-2 reverse (manual tape flip required for second pair); mono compatible; sound-on-sound/multiplay overdub facilities; no auto-reverse.

• Tape Speeds — Three speeds:1⅞ ips (4.75 cm/s)
  3¾ ips (9.5 cm/s)
  7½ ips (19 cm/s)
  

• Reel Size — Up to 7 inches (18 cm) maximum diameter.

• Frequency Response (approximate, within ~3 dB tolerances; varies by tape/condition):At 7½ ips: 35 Hz – 25,000 Hz (some serviced units reach 26 kHz –3 dB or 28 kHz –6 dB)
  At 3¾ ips: 35 Hz – 19,000 Hz
  At 1⅞ ips: 35 Hz – 11,000 Hz Among the widest in Philips' consumer lineup—hi-fi capable at higher speeds.
  

• Wow & Flutter — 0.15% (DIN) at 7½ ips (some sources: 0.05% in optimal/serviced condition); <0.2% at 3¾ ips; <0.3% at 1⅞ ips (excellent from three-motor design).

• Signal-to-Noise Ratio — 58 dB (DIN) or >60 dB (some sources claim better than 60 dB with low-noise tape; strong transistor performance).

• Heads — 3 heads: separate record, playback, and erase (permalloy construction; enables real-time off-tape monitoring/A-B comparison).

• Drive System — Three motors (1 × capstan + 2 × reel motors); belt drive to capstan/flywheel; idler tires/clutches; mechanical or electronic tension control; fast wind/rewind; precise braking.

• Electronics — Fully transistorized; printed circuit board amplifier.

• Amplification & Speakers — Built-in stereo amplifiers (in full versions); dual internal loudspeakers (often elliptical or integrated); output power adequate for monitoring (typically ~few watts per channel; some integrated configs allow direct speaker drive).

• Inputs —Microphone: 0.2 mV / >2 kΩ (stereo pair possible).
  Line/radio/phono/tuner: 100 mV / 100 kΩ (or similar).
  DIN-style connectors standard.
  

• Outputs —Line out: ~1 V / 50 kΩ.
  Headphones (monitor).
  External speakers or amp.
  DIN-style.
  

• Features —Twin illuminated VU meters (needle type; active for record/playback).
  Push-button transport controls (mechanical in most; illuminated tip-touch style).
  Separate tone controls (bass/treble).
  Input mixing.
  4-digit tape counter.
  Off-tape monitoring (source/tape switch).
  Pause function.
  Portable/tabletop design with lid/handle; vertical/horizontal orientation.
  

• Power — AC mains (multi-voltage switchable, e.g., 110–240 V); consumption ~60–120 W.

• Build & Dimensions — Tabletop case (often wood/teak or silver finish); approx. 415–535 × 380–430 × 200 mm (variants around 16.3 × 16.9 × 7.9 inches); weight ≈10–15 kg.

• Manufacturing — Primarily Austria (Philips Österreich).

Performance & Legacy Context

The N4512 was Philips' late-1970s high-end consumer open-reel—celebrated for its wide bandwidth (up to 25–28 kHz in serviced units), low wow/flutter from three motors, high S/N ratio (>58–60 dB), and 3-head monitoring for precise recording. It delivered superb stereo imaging, dynamics, and clarity at 7½ ips, making it a strong contender against Japanese rivals of the era. Serviced examples often exceed factory specs, with users praising its "long-life heads" and reliability when belts/caps are refreshed.

Common issues today: Belt/idler goo (multiple belts—main drive, counter, etc.—need full kits), dried electrolytic capacitors, transistor aging, dirty heads (3-head alignment critical), worn idler tires/clutches, and occasional motor or transport faults. Restorations are common and transformative—many YouTube tests show excellent post-service performance. Service/user manuals widely available (HiFi Engine, Elektrotanya—full schematics, alignment, bias info).

Compared to siblings:

• N4506 — Very similar flagship (often overlapping specs; N4512 sometimes seen as a variant with minor refinements).

• N4504/N4502 — Related deck-only models (two speeds in some).

• N4520/N4522 — Later quartz-PLL successors with 10.5" reels and even higher specs.