Philips N4510

The Philips N4510 (including variants like N4510/00 or rebranded as Maestro 4510 in some markets) is a mid-1970s high-end consumer stereo reel-to-reel tape recorder, produced approximately 1972–1975 (manufactured primarily in Austria by Philips Österreich). It was a premium model in Philips' N45xx solid-state hi-fi series, often described as a "Magno Control" flagship with exceptional build quality, three-motor drive, three-head configuration, and hi-fi performance compliant with DIN 45500 standards (using low-noise tape). The N4510 was designed for serious home hi-fi enthusiasts and semi-professional use, offering superior tape handling, wide frequency response, and integrated features like off-tape monitoring and built-in stereo amplification.

This was a 4-track (quarter-track) stereo recorder with true stereo recording and playback in both directions, built-in stereo power amp and speakers (in full versions), and a focus on audio fidelity over gimmicks like auto-reverse (unlike the N4450).

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 (some references note compatibility with larger reels in certain setups, but standard is 7").

• Frequency Response (approximate, within DIN tolerances; varies by tape/condition):At 7½ ips (19 cm/s): 40 Hz – 20,000 Hz
  At 3¾ ips (9.5 cm/s): 40 Hz – 15,000 Hz
  At 1⅞ ips (4.75 cm/s): ~60 Hz – 10,000 Hz Excellent hi-fi extension at higher speeds.
  

• Wow & Flutter — Approximately 0.05–0.07% at 7½ ips; ~0.15% at 3¾ ips (very low thanks to three-motor and precise capstan control).

• Signal-to-Noise Ratio — >50 dB (often cited as 50–56 dB or better with low-noise tape; strong for the transistor era).

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

• Drive System — Three motors (2 × DC reel motors + 1 × capstan motor for transport); belt drive to capstan/flywheel; idler tires/clutches; constant speed recovery within ~300 ms; fast wind/rewind; precise braking and tension stabilizers.

• Electronics — Fully transistorized; printed circuit board amplifier.

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

• Inputs —Microphone: low-level (~0.2 mV / >2 kΩ; stereo pair possible).
  Line/radio/tuner/phono: ~100 mV / 100 kΩ.
  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).
  Illuminated tip-touch/push-button transport controls.
  Separate tone controls (bass/treble).
  Input mixing.
  4-digit tape counter.
  Off-tape monitoring.
  Pause function.
  Optional remote control (DIN 5-pin).
  Portable/tabletop design with lid/handle; vertical/horizontal orientation.
  

• Power — AC mains (110–120 V / 220–240 V switchable, multi-voltage); consumption 60–75 W.

• Build & Dimensions — Tabletop case (often wood/teak or silver finish); approx. 515 × 380 × 200 mm (20.3 × 15 × 7.9 inches); weight ≈10 kg (some listings up to 25 kg for integrated versions).

• Manufacturing — Primarily Austria (Philips Österreich).

Performance & Legacy Context

The N4510 was Philips' high-end consumer open-reel in the early-mid 1970s—praised for its three-motor drive (smooth, stable transport with low wow/flutter), 3-head monitoring (accurate real-time listening), wide frequency response (up to 20 kHz at 7½ ips), and integrated stereo amp/speakers for convenience. It delivered excellent clarity, dynamics, and stereo imaging for home hi-fi recording and playback, often compared to contemporary premium decks.

Common issues today: Belt/idler goo (multiple belts need full replacement), dried electrolytic capacitors, transistor aging, dirty heads (3-head alignment critical), worn idler tires/clutches, and occasional motor or logic faults. Restorations are common and highly effective—many serviced units perform exceptionally well. Service/user manuals widely available (HiFi Engine, Elektrotanya, Internet Archive—full schematics, alignment, bias info).

Compared to siblings:

• N4504/N4502 — Similar deck-only models (two speeds in some, close chassis).

• N4506 — Later/related flagship with potentially wider response or refinements.

• N4520/N4522 — Successors with quartz PLL, 10.5" reels, and higher specs.

• N4418/N4422 — Earlier three-motor contemporaries with similar heads/speeds but less advanced.