REFURBISHED SENNHEISER MDS 1 / GRUNDIG GDSM 200 - STEREO DYNAMIC 1960 XLR

​The Sennheiser MDS 1

Grundig GDSM 200

A Precision Instrument for Stereo Music Recording

Introduction
Every engineering project begins with a reason to exist.
By the mid-1960s, recording engineers could already choose from a wide range of stereo microphone systems spanning consumer and professional applications. Within this landscape, the MDS 1 occupies the most ambitious end of its family.
Its continuously adjustable stereo assembly, capsule selection and overall manufacturing quality indicate a project in which technical performance consistently took precedence over manufacturing economy. Greater flexibility in microphone placement, improved geometric precision, mechanical stability and professional acoustic performance were brought together into a single recording instrument intended for demanding studio recording.
More than sixty years later, those engineering decisions remain the defining characteristic of the MDS 1, continuing to justify its place among the most thoughtfully engineered stereo recording systems of its period.

OPTICAL CONDITION: 
Very well-preserved original condition with only light signs of professional use.

TECHNICAL CONDITION:
Both microphones inspected, serviced and tested. Capsule assemblies cleaned, foam supports replaced, stereo assembly adjusted, balanced XLR conversion completed.

INCLUDED:
Original stereo assembly

Matching microphone pair

Custom-fitted hard case

More Sennheiser Than Grundig
Although many surviving examples carry the Grundig designation GDSM 200, the microphone itself is fundamentally a Sennheiser development. Produced during the long-standing collaboration between the two companies, the MDS 1 reflects Sennheiser's engineering philosophy while appearing under the Grundig name.

The Assignment
The MDS 1 entered a market where stereo recording was already mature. Engineers had no shortage of ways to record in stereo. The opportunity lay in building a recording instrument that offered greater precision, flexibility and mechanical confidence than existing solutions.
Within its own family, the MDS 1 occupies the most ambitious end of the range. Every major design decision points towards the same objective: expanding the engineer's freedom in microphone placement while preserving geometric accuracy, structural stability and the versatility of two fully independent professional microphones.
Every component of the MDS 1 contributes to that objective.

Stereo Assembly
The MDS 1 combines two fully independent dynamic microphones with a continuously adjustable stereo assembly. Both microphones detach for individual use before locating positively back into the stereo bridge within seconds.
Each microphone rotates and pivots independently, allowing an exceptionally wide
range of stereo geometries. Measured from diaphragm to diaphragm, the assembly provides spacing from virtually 0 cm to approximately 22 cm, giving the engineer exceptional freedom within a single recording system.
The assembly operates with exceptionally tight tolerances, allowing smooth adjustment while ensuring the chosen geometry remains exactly where the engineer leaves it.

Manufacturing
Every visible part fulfils either a mechanical or an acoustic purpose. Rather than appearing as separate mechanisms assembled into a common housing, the stereo bridge, microphone bodies and adjustment system give the impression of having been developed as one coherent instrument.
402/3 Capsule
The MDS 1 employs the Sennheiser 402/3 moving-coil capsule, one of the company's defining professional dynamic capsule designs of the 1960s.
Technical: 402/3 moving-coil dynamic capsule; cardioid; front acoustic resonator; intended for professional studio recording.
Removing the grille reveals a compact acoustic assembly with three foam support elements and an integrated acoustic guide.

Sound
The engineering of the MDS 1 ultimately serves one purpose: musical recording. Its tonal balance reflects the same philosophy found throughout its construction. The microphone changes perspective rather than personality across distance, encouraging experimentation with placement as part of the recording process.
Within the Grundig Stereo Family
The MDS 1 represents the most complete expression of this family of professional stereo microphones, combining greater mechanical freedom, higher manufacturing quality and the 402/3 capsule into one recording instrument.

Production Facts
Manufacturer: Sennheiser electronic KG
Distributed as: Grundig GDSM 200
Germany • 1960s • Two detachable cardioid dynamic microphones • 402/3 capsules •
Precision stereo bridge • Balanced XLR conversion.

Complete MDS 1 systems appear only occasionally. Most enquiries concern restoration rather than sale, owners continue to keep and use them. Some microphones become collectables. Some become investments. The MDS 1 became a working instrument that owners choose to keep.