Technics RS-1520

AVForums

Help Support AVForums:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

El Sid

AVForums Super Veteran
*
AV Forums Supporter
Joined
May 26, 2016
Messages
1,992
Reaction score
452
Location
Jhb
@marcochezzi feast your eyes on this beauty:

1690296295488.png

A REBUILD LIKE NO OTHER: FULL BESPOKE RESTORATION AND MODIFICATION



The Technics RS-1520 Reel-To-Reel Tape Deck is a semi-professional machine that has great similarities to the 1500 but with a separate dual mono preamplifier section that features more adjustability. The Technics RS-1520 Reel-To-Reel Tape Deck is a half-track track record, quarter-track playback deck with a switch on the headlock to change the playback head to quarter track. It has the Isolated Loop tape path developed by Technics which improves wow and flutter (.018%) as well as modulation noise. A large 34mm capstan with 2 pinch rollers makes for a very smooth and stable tape path with an electronic tension control system. The tape tension on the Technics RS-1520 is low compared to many other machines, so for those using older tapes with rippled edges, this may not be ideal. A Quartz-Locked Direct-Drive Capstan Motor completed the well-designed assembly. Logic-controlled electronic braking, which applies reverse torque to the motor before deploying a mechanical brake, results in a very smooth transition between function selections and virtually no tape stretch.



The Technics single capstan system offered advantages over double capstan as variations in the speed of two capstans and the pressure of the two pinch rollers to maintain the desired temp tape tension makes speed and tension adjustment complex and difficult often increasing the tape tension which is not desirable. The relatively long distance between the two capstans over which the tape must stretch contributes to higher modulation noise and scrape flutter. In contrast, the Technics single capstan system maintains the same speed and pinch roller pressure on both sides of the capstan. The wide contact area between the pinch rollers and the single extra-large capstan allows for lower tape tension, about 80 g and is very steady because the tape path between the capstan and the reversing roller is relatively short. So modulation noise, wow & flutter and level fluctuations are dramatically reduced. Add to this the quartz locked slow speed direct capstan drive system, aided by tension-controlled direct drive reel motors and air-dampened tension rollers the Technics isolated loop system achieves excellent overall performance.

***********************************************************************

The Technics 1520 has long been regarded as one of the prized tape decks. Impeccable consideration to the points only the most meticulous of audiophiles would understand.

Below is a description of this one-of-a-kind rebuild process:

REEL MOTORS

The tape recorder motors are totally disassembled. Plastic tridents, which are subject to breaking easily, are replaced with metal tridents made from non-magnetic aluminium bronze. Bronze bearings inside the motors were cleaned, and filled with lubricant.

Brake drums were removed from the shaft, and the old paint was stripped. Repainted with glossy hard scratch-resistant high temp paint. The quality of this paint is crucial for proper brakes. Table painted to base machine colour. Shaft assembly with brake drums and tridents balanced. Motors assembled.

CAPSTAN MOTOR

The tape recorder capstan motor was disassembled, and cleaned. The aluminium cup was removed and replaced with another one made from nonmagnetic aluminium bronze. Precisely machined and polished. Bearings replaced with original NOS NSK(made in Japan) bearings. Incredibly silent. Capstan assembled, and installed.

VU METERS

Original aluminium background sheets VU Meters removed. Scanned with the precision scanner. A new graphic file suitable for laser engraving was created. Replaced with non-magnetic copper sheets, laser engraved, and painted to base machine colour. Graphics 24K gold plated. The black paint from the arrows was removed, arrows were painted with fluorescent paint (0xBD09F5 colour).

HEAD BLOCK

The tape recorder head block was disassembled. Plate stripped, cleaned, and painted to base machine colour. New metal letterings and some metal accents were applied. Heads had incredibly low usage, relapsed & polished under water. Resoldered, realigned. The head block was reassembled. 4t-2t switch disassembled, cleaned and reassembled.

TAPE COUNTER

Large 128x22px screen with bright YELLOW pixels. Powered by SSD1305 and Teensy4.0 (600MHz) controllers. Auto-scaling with speed switch on the left panel. With memory on power off. Prewired for future installation of WiFi remote control and programming block. Screen installed on totally reengineered counter and cue plate, 3D printed on Formlabs3+ printer from high temp resin, powder coated to base machine colour. A new reset switch and precisely machined button were installed. CUE functionality is untouched.

CONTROL BUTTONS

Control buttons block disassembled, Plastic buttons replaced with CNC machined aluminium, powder coated to the base colour. RECORD, PAUSE and PLAY buttons have light bulbs which are visible in the corresponding mode through symbols.

TAPE PATH

All bearings were replaced with the original NOS NSK. All parts were polished, replaced with non-magnetic aluminium bronze where possible, and realigned. Some decorative parts were added.

AUDIO CONNECTORS

All back connectors were replaced with gold plated. AC cord connector added. All visible metal parts are handmade from non-magnetic aluminium bronze polished.

METAL PAINTING

Aluminium bronze C62400 composition contains up to 11.5% of aluminium, which creates a protective oxide film almost immediately after polishing. Will remain shiny for a long time. The colour is slightly darker than gold by design. Needless to say, all letterings are made from the same metal, 0.75mm raised. The splicing block is fully functional with spring-loaded levers. Cuts for blades are made for 22.5 and 45 deg for right and left-handed people. Insert for lower panel levers also CNC machined from C62400, polished. Also, needless to say, but, the deck is fully recapped and readjusted. All old Philips bolts were replaced with new HEX just to make future maintenance easy. Lubricated, aligned.

SIDE PANELS

Side panels are made from African Rosewood AKA Palisander (while machining smells like roses it's funny). Treated with special blend oil, polished. Each flange on the side panels has the engraving "Technics RS-1520".

THE TAPE DECK ASSEMBLED WITH NEW BESPOKE-MADE FEET, NAB ADAPTERS AND REEL SPOOLS.

Technics RS-1520 A Rebuild Like No Other By Alter Ego Appearance

Alter Ego Appearance combines art with technical skill. Custom would be an understatement as each machine is its new creation. Alter Ego Appearance brings tape deck restoration to the next level. Providing complete rebuilds and custom modifications. Creating brand new front panels, jewellery grade metal lettering, powder coating, 3D printing, coding for custom modifications and much more.

Alter Ego Appearance - New York - USA
 

Latest posts

Top