BDS File

What are BDS files and how to open them

Are you having problems opening a BDS file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your BDS files.

What is a BDS file?

BDS files have multiple uses, and Ben Daglish SID Chiptune is one of them. Read more about the other uses further down the page.

Ben Daglish SID Chiptune

Ben Daglish SID Chiptune files store songs specifically composed for the Commodore 64's SID sound chip using a custom format developed by musician Ben Daglish. These files package together the tune data and the playback code (often called a SID driver), in a binary form designed to be played back on the original hardware or accurate emulation. They preserve Daglish's musical style, sequencing, and soundchip‐specific effects.

These files are authored by Ben Daglish (sometimes spelled Benn Daglish) by exporting or assembling tune data into his personal SID‐player format. Once created, the files are typically distributed among Commodore 64 music collections and played using SID‐capable players that support Daglish's driver routines. They are not simply raw audio; they contain note instructions, registers writes, and code routines for initializing and running on 6502 CPU machines with a SID chip.

Internally the format is identified by a signature in the header: at offset 32 there is the ASCII signature "p.NuDAGLISH!", along with specific byte sequences near the start (including values around offset 0 and at offset 24) that mark it as a Benn Daglish SID Chiptune file.

How to open BDS files

Important: Different programs may use files with the BDS file extension for different purposes, so unless you are sure which format your BDS file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested two different BDS openers which you will find listed below.

Last updated: August 23, 2026

All known file formats using extension .BDS

While Ben Daglish SID Chiptune is a popular type of BDS-file, we know of 2 different uses of the .BDS file extension. Different software may use files with the same extension for different types of data.

SPICE Binary DSK

SPICE Binary DSK files store highly detailed three-dimensional shape models for solar system bodies, spacecraft components, or other extended objects. They are created by the SPICE toolkit's Digital Shape Kernel (DSK) subsystem. These files are used when simple ellipsoid or other basic models are insufficient and geometry computations - such as ray-surface intercepts - require precise surface detail.

The creation of these files is typically done by the SPICE utility MKDSK, which takes as input shape data in a text form (such as triangles or height grids) along with metadata about the body, reference frame, and coverage. The shape is represented internally using tessellated plates (triangular facets). After creation, SPICE-based applications read them to compute things like visibility, occultations, surface normals, or relative geometry between spacecraft and the target. Metadata and descriptive comments are included in a dedicated comment area.

These files follow SPICE's DAS architecture ("Direct Access, Segregated") and are a specific kind of kernel with the type DSK ("Digital Shape Kernel"). They allow fast, random access to character, integer, and double precision data arrays, and are organized internally as linked segments under the DLA ("DAS Linked Array") format. The only supported data type in current SPICE versions is "type 2", modeling surfaces as a collection of triangular plates.

There is a fixed signature in the file header: at offset zero the file begins with the ASCII characters "DAS/DSK " (hex bytes 44 41 53 2F 44 53 4B 20), which identifies it as a SPICE DAS/DSK binary file.

Various apps that use files with this extension

These apps are known to open certain types of BDS files. Remember, different programs may use BDS files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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