ADC ALT-1

 The recent success of ADC's foray into the component tonearm business with the LMF-1 seems to have prompted the release of a less costly version, whereby the tapered carbon-fibre tube of the LMF has been replaced by aluminium and the end product labelled the ALT-1. this detachable headshell arm is also used in a similar form in the 1600 and 1700 turntables. The counterweight assembly is shorter than that on the LMF-1, and is of a rotating scale rether than the more complex calibrated dial type. The arm is supplied with a simplified sliding base compatible with SME fixing centres which made for easy setting up and alignment (the SME type base is an extra with the LMF-1).

 Proving not to be as well adjusted as we would have liked the horizontal bearing was rather slack and showed a moderate if not particularly low friction of 40 mg. However biasing was fine, and downforce calibration very good. The resonance graph revealed an untidy characteristic, although as the modes were well-controlled the result was in fact above average. However, if this is compared with the new graph for the LMF-1, the latter's superior performance in this department is only too apparent, albeit at twice the price. Lead capacitance was 180 pF, which is fairly high and may be worth bearing in mind with some cartridges.

 The value is quite good, and the fact that there are few low mass arms around at this price level works to the ALT-1's advantage, since the more compliant cartridges should work well in this model.

On a good turntable the sound quality produced by this arm was judged as above average, despite some imprecision of stereo imaging.

Specifications

Tonearm length:  237 mm (9,33') Pivot to stylus tip

Cartridge Offset Angle:  24,6°

Stylus Tip overhang:  19 mm (0,760")

Zero Tracking Angle Error:  at 69 mm (1,7") and 129 mm (5,06")

Maximum Tracking Angle Error:  1,25° at 60, 94 and 146 mm (2,38", 3,69" and 5,75")

Cartridge Weight Range:  4 to 11 grams

Stylus Force Range:  Calibrated 0 to 4 in ¼ g steps

Bearings Type:  Stainless steel ball bearings

Effective Arm Mass:  7,0 grams with counterweight (set for ADC XML cartridge)

Anti-Skate Range:  0 to 4 grams

Arm Wiring:  18 pF per channel

Lead Wires (stereo):  220 pF per channel (normal)

Lead Wires (CD-4):  100 pF per channel (available accessory)

Tonearm Lifter

Cue:  lever control

Damping:  Viscous oil damped

Height Adjustment:  Lifter is factory adjusted