JD-800 and JD-990 DAC Calibration

This is my JD-800. The DAC board is at left.

JD-800 and JD-990 DAC Calibration

Calibration for the JDs Digital to Analog Converters (DAC).

Just to remember, the DAC is that circuit where the digital signal is converted to analog. This is a very important part of the JD, because the quality of the result it does.

From Analog.com:

In principle, you give a digital input to a DAC and it provides an accurate output voltage. In reality, the accuracy of the output voltage is subject to gain and offset errors from the DAC and other components in the signal chain. The system designer must compensate for these errors in order to get an accurate output voltage. This can be implemented with external components and post-manufacture trimming. Digital calibration modifies the input sent to the DAC such that the gain and offset errors are taken into account thus removing the need for external components and trimming.

Thanks to Don Solaris, a JD-Master for posting this at his site. Click the links to be redirected.

• JD-800 DAC Calibration

• JD-990 DAC Calibration

If you already does not have the JD Service Manual get it here: JD Manuals.


Note: Please, if the links does not work, notify me at comments to update it. 

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Memory Card Battery Replacement / cartridge

It is important to remember you cards / cartridge have an internal battery.

This is the former process for replacement.


All rights: @Roland Co.


Download the original PDF file from Roland US:  Roland_Memory_Card_Battery_Replacement.pdf

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Memory Card Battery Replacement Instructions

The Roland M-512, M-256 and M-128 memory cards each have an internal battery.

If you need to replace the internal battery, please use the following images as a guide.


Be sure to use the specified battery (CR-2016) - This is a very popular type usually easy to find.




1)  Locate the battery tray and use your thumbnail or the blade of a small flat-head screwdriver to gently loosen the battery tray.

 2) Gently pull the battery tray completely out of the memory card.

 3) Make a note of which side of the battery is facing up so you can position the new battery correctly.

4) Take care not to touch the new battery with your bare fingers as this can shorten battery life.
 

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Manuals: JD800 and JD990 (Updated)

The Roland JD-800 and the JD-990 have strong sound features and the user manuals are a "must have" to anyone who wants to use in depth all resources and to learn about sound synthesis.

Roland has made manuals for most of their products available as free PDF downloads.
This material is @ Roland Corp.

Note: All "Google Docs" links must be working. I can't assure the external Roland links are still active.

English Language Manuals	Size	Sources
JD-800 Owner´s Manual	8.982 Kb	Roland US		Google Docs.
JD-800 User´s Guide		Roland US		Google Docs
JD-800 Midi Implementation	424 Kb
JD-800 Turbo Start Guide	62 Kb
JD-800 Service Manual	39.2 Mb			Google Docs
JD-990 Reference	28,5 Mb			Google Docs
JD-990 Owner´s Manual	7.675 Kb	Roland US		Google Docs
JD-990 User Guide	6.333 Kb	Roland US		Google Docs
JD-990 Turbo Start Guide	62Kb
JD-990 Service Notes Manual	62Kb			Google Docs
JD-990 Patch/Waveform/Rythm List	1.348 Kb	Roland US		Google Docs

The Original Japanese manuals:

Japanese Language Manuals	Size	Sources
JD800 User´s Guide	2.622Kb	Google Docs	Here the 3 manuals from Roland.jp site
JD800 Reference Part 1-4	3.953Kb	Google Docs
JD800 Reference Part 5	2.486Kb	Google Docs
JD990 User´s Guide	1.043Kb	Google Docs	Here the 2 manuals from Roland.jp site
JD990 Reference	6.315Kb	Google Docs

From www.bluesynths.com:
"We HAVE TO add this user manual to the literature list. It's simply a
great piece of synthesizer literature. Contains not only detailled
explanations, drawings and graphics about each part of the JD-800, but
also lots of background information (music theory, how to create
realistic string sounds, about using effects, etc). 200 pages."