Bang and Olufsen

Beogram 4000 tangential tracking turntable.

 

Produced between 1972-1974 with a tangential tracking, fully automated arm. The turntable is belt driven with a strobe light as a speed checking/adjustment aid.

Despite the sleek, elegant appearance, it is in fact a very high specification deck. The massive centre bearing,  the mechanical parts of the arm control system, and the arm itself, were all mounted on a die cast sub-chassis, suspended from the main chassis (also die cast throughout) from steel wires hung on tapering single leaf springs. These three spring assemblies, adjustable for levelling, supported the sensitive parts of the record player, and effectively isolated them from any external vibrations. This method of suspension, called either “pendulum” or “danceproof”, was patented and featured as part of all subsequent Beograms.

The secondary arm "reads" the strobe lines on the platter, determining whether a 7" or 12" disc is to be played. The speed of the platter then adjusts automatically to suit. Speed change had to be undertaken manually for 12" singles! If there was no record on the platter, the arm returned to it's rest place without attempting to lower.

The main ultra-light weight arm tracks at a mere 1 gram when fitted with the top-of-the-range B&O MMC 20CL magnetic cartridge. The arm is driven accross by a servo motor which is activated continually in bursts when the arm is no longer perfectly perpendicular to the record surface i.e it moves nearer the centre by a tiny fraction. This is done with the aid of a light beam passing through a slot, activating a sensor which sends a voltage to the arm servo to operate it until the arm is perendicular again. At the end of the side, the servo will power the arm to the resting place.

In 1972 the Beogram 4000 won the iF Design Award and in 1973 it received the Danish ID Award; Later that year it was included in New York's Museum of Modern Art (MoMA) Design Collection. It also received the English Blue Ribbon award that year for outstanding design who labelled the deck as "the most awarded product within the Radio trade".

It’s worth noting that, whilst this deck was designed as part of a Bang and Olufsen system, with an adaptor lead, it can be used with any amplifier with a conventional moving magnet cartridge input.

Thinking of buying a Beogram 4000?

Just a few pointers you may find useful...

 

  • Most examples in reasonable condition are repairable by a competent engineer. The Beogram 4000 service manual is available on the excellent Vinyl Engine website. One of the frequent problems with a deck that hasn't been used for a while, is that the arm doesn't lower. One possible cause may be that the hydraulic mechanism seizing up up and requiring “cleaning up”. Don't keep attempting to lower the arm until this has been done or else the solenoid may burn out.
  • As with most vintage equipment, sorting out the exterior and cosmetics can be a lot more fraught than repairing the electronics. Watch out particularly for small cracks on the perspex lid near the two hinge areas. This happens when the lid is allowed to flip back quickly by the sprung hinges without support. Always keep a steadying hand on when opening and closing the lid.
  • Fingerprint marking on the aluminium pressure pads is not usually removable and can permanently spoil the look of the deck. Make sure you see a good photo of the aluminium plate used for the arm manual lift/lower functions as well as the speed change control before making a decision to buy.
  • Finding the correct replacement rubber belts can be a headache. If the wrong one is used, whilst it may work, there may be excessive rumble noise caused by motor vibration being transferred to the platter.
  • Be very careful when removing or refitting the cartridge onto the arm tube. The cartridge is held by a small plastic lug protruding from the arm tube which is easily be broken off.
  • Don't rely on the dial at the rear of the arm when setting the tracking weight. It's often inaccurate so use a stylus balance if possible.
  • The two aluminium top-plate panels can be removed by sliding the wooden plinth trim forward by about half an inch. Slide the plinth sides forward from the back by applying a little pressure at the ends. There are two black tiny metal clips which should be held back with a very small screwdriver blade. This releases the wooden sides and allows them to slide forward, freeing the aluminium panels. Lift them away carefully, making sure the stylus guard is in place first!
  • For a very good example of the Beogram 4000, expect to pay in the region of £1000. An excellent example may be as much as £1500, and a genuinely mint one (uber rare), even more. The Beogram 4000 is undoubtedly a beautiful example of audio reproduction equipment design. It came at a time when home audio equipment began climbing up the sound quality mountain remarkably quickly with genuine progress, unlike much of the over-priced, over-hyped products of today.
  • The Beogram 4002 and 4004 are simplified versions of the 4000, also great sounding decks. Are they as good as the Beogram 4000? I wouldn't like to take a blindfold test, but the 4000 as a technical tour-de-force appeals more to my techy, nerdy nature.
  • If you are lucky enough to own a Beogram, use it often. These decks like to be used regularly which avoids having any of the myriad of moving parts seizing up. As a deck which has been properly serviced beds in, it will sound even more gorgeous!
  • Don't replace electronic components e.g capacitors that are not faulty. It's a waste of time and energy and may detract from the value of the deck as it has been “messed about”.
  • If you own a Beogram which requires repair and live in the UK, I can recommend an excellent service engineer who must be the country's foremost expert on classic Bang and Olufsen. He is based in Surrey, England but will only accept repairs when delivered in person.
  • Sound quality is very, very good indeed. The LF (low frequencies) are deep and tight. Stereo separation and image depth is superb. Tracking is very “relaxed” and stable too, with only strong sibilance causing a bit of a problem on my example. Make no mistake, this is a great sounding deck despite the vintage.

SPECIFICATIONS

TYPE: 5215 (1972 - DEC 1974)
SPEEDS: 33 - 45 RPM. ELECTRONIC SECTION
PICKUP-ARM SYSTEM TANGENTIAL
AUTOMATIC SPEED SELECTION
CUEING CONTROL ELECTRONIC AIR PRESSURE DAMPED
DRIVE SYSTEM: BELT
MOTOR SYNCHRONOUS ELECTRONICALLY CONTROLLED
STROBOSCOPIC SCALE LIGHT INDICATOR 33 AND 45 RPM: 50 AND 60 HZ
WOW AND FLUTTER: < +/- 0.05 %
RUMBLE A: > 46 DB, B: > 65 DB
SPEED CONTROL RANGE: > 6 %
PICK-UP: MMC 20 CL. RECOMMENDED STYLUS PRESSURE : 1 GRAM
POWER SUPPLY: 110 - 130 - 220 - 240 V / 50 - 60 HZ / 40 W
DIMENSIONS H X W X D 10 X 49 X 38CM
WEIGHT 12 KG