Information on MUSE Decoders

User Guides

I currently have manuals for the following models, and am working on adapting them into concise user guides. Direct translations would be both laborious and of limited use, since much of the information in the manuals either is redundant, such as detailed connexion diagrammes, or specific to the discontinued satellite broadcasts and therefore of little practical value. My aim is to condense the most generally useful information into a convenient form.

Scans or paper copies of manuals I do not have listed, or other relevant materials, will be welcomed.

Models and Functions

The information below has been gathered from various print and on-line sources, including sale listings, and it is neither entirely complete nor entirely accurate. (The list of Sony products was checked against a Sony website, and should be reliable.) In particular, it is possible that some television models listed as having internal decoders or downconverters were actually sold as package deals with external receivers. Corrections and additions, especially with references, are appreciated, as are photographs.

MUSE Decoders

Four and a half "generations" of MUSE decoder were distinguished by the Japanese electronics industry. First-generation units are laboratory and demonstration models only, using discrete logic, larger and more massive than the HDTV sets themselves, with power consumption in the kilowatts. Any surviving examples are probably in museums. The original Sony consumer model, MST-1000, is typical of the second generation, made possible by the introduction of special LSIs. These were rapidly followed by less-expensive "2.5th generation" models with smaller chipsets, such as the Sony MST-2000. Third generation decoders are more highly integrated again, while the fourth generation are "single-chip" types mostly installed into television sets.

In general, due to more sophisticated filters and other improvements in circuitry, later-generation models give better picture quality. Additionally, later decoders will make the best use of improvements in encoding which were introduced over the life of the MUSE format.

Unless otherwise noted, decoders have MUSE line input, YPbPr component video output, bitstream output, and AFC output terminals. Almost all have dual video outputs, both YPbPr unless noted as switchable or one each YPbPr and GBR. Some decoders incorporating BS tuners have NTSC outputs only active when an NTSC signal is received, which are not noted. In general, decoders do not upconvert NTSC video.


Includes audio downmix (3-1, 2-2, or LCR stereo to L'R'), either selectable or on separate jacks
Includes BS tuner
Additional video output in GBR format
Video output(s) switchable between YPbPr and GBR
Separate sync (HD, VD) outputs
5-channel audio outputs (Left, Right, Center, Left Surround, Right Surround)
4-channel audio outputs (Left, Right, Center, Surround, or 1-4)
Optical (TOSlink) digital audio outputs in addition to analog
Coaxial digital audio outputs in addition to analog
Includes NTSC downconversion outputs
Includes NTSC downconversion outputs with S-Video connector
Rear-panel electrical power outlet
With wireless remote control unit
Requires remote control for basic functions such as selecting line unputs

MUSE Downconverters

In general, the 525-line video signal produced by what are termed "M-N converters" has a frame rate of 30.00 per second, as opposed to 29.97 per second for the NTSC colour standard. As a result, the chroma subcarrier does not maintain the correct timing relationship with the scan lines, which can cause difficulties, especially in the processing of composite video. Therefore, if possible, it is best to use a component, RGB, or Y-C separate (S-Video) connexion. Many models have loop-through connexions for NTSC video & stereo audio.

Key (Supplementary)

"Full" mode, outputs the 16×9 frame for wide-screen TVs
"Wide" mode, letterboxes the 16×9 frame into 4×3 for standard TVs
"Zoom" mode, outputs the center 4×3 portion of the 16×9 frame for standard TVs
S-Video outputs in addition to composite

HDTVs with Internal MUSE Decoders

Some models may have HD video outputs. Most probably have multichannel audio outputs.

TVs with Internal MUSE Downconverters

Video main page
Updated 2011-296