Chapter 2 - Product History

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2.1 - History Introduction

The following outlines possible configurations of K250s in the field. When the K250 was first introduced to the field in August of 1984 the K250 contained Version 1 software and no options. Please be aware that some options are required and some are optional. Please refer to the "Software Versions Versus Options Available" list included in this chapter for configuration information.

Note: Specific part numbers are mentioned in this document pertaining to parts included in option kits. However, not all part numbers required for certain options are mentioned. This document has been prepared to give you a brief history of the options and updates for the K250, K250X and the RMX 250 and 225. This chapter is not meant to replace the installation procedure supplied with each option kit.

The Kurzweil 250, K250X and RMX contain the following printed circuit boards:

CPU/Central Processing Unit CGP/Channel Group Processor Channel Audio Slider LCD Control Panel Base and Treble Keyswitch boards (K250 only) Power Supply (internal, RMX models only)

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2.2 - February, 1985

Version 2 software update--a no charge update Ram Sequencer Expansion--purchased option bringing the Sequencer from 4K to 8K Sound Modeling Program (25kHz)--purchased option*

*Sound Modeling Program also referred to as sampling

The Version 2 free software update was offered to all K250 owners and required some modification to the CPU board and the replacement of the 8 software EPROMs located at:

82051001    U54        82051101    U38
82051201    U53        82051301    U37
82051401    U52        82051501    U36
82051601    U51        82051701    U35

The RAM Sequencer Expansion required the installation of four memory chips part no. 62000501 in locations U28, U29, U43 and U44. The original Ram Sequencer Expansion kit included a replacement for U95 on the CGP board, however, this part is not included in the current kit.

The Sound Modeling Program required a unit with Version 2 software and involved the update of three p.c. boards, the CPU, CGP, Channel; and the possible replacement of the Audio board.

The CPU board with Version 2 installed only required that you install part no. 82000408 in U25, part no. 82000409 in U40, part no. 82000410 in U26 and part no. 82000411 in U41.

The CGP board required 3 cuts to the solder side of the board and 3 jumps to the component side of the board. It also required the installation of 20 DRAM chips in locations U25 through U29, U33 through U37, U51 through U55 and U72 through U76. The CGP board while installed in the K250. These locations are easily found by looking at the inner right hand corner of the CGP board.

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The Channel board required the installation of U60, part no. 63001201. Some units did not have a socket at this location; and, therefore, required the addition of that socket. This socket was supplied with the kit. Kurzweil never recommends that this part is soldered into the board. It was also required to check values of certain resistors and capacitors on the Channel board and the addition or replacement of these parts.

The Audio board needed to be replaced for any unit produced prior to February of 1985. Therefore, Kurzweil offers two Sound Modeling Program kits, one with Audio board and one without. (Kurzweil offers these kits at the same cost.) The part number of the Audio board required for Sound Modeling Program is 12011001. Some boards may not actually have this part number printed on it, but will have the correct p.c. board fabrication number, 33011001. The old Audio board that needs to be removed is part no. 12001001 or p. c. board fabrication no. 33001001.

2.3 - May, 1985

Sound Block A--purchased option

The Sound Block A board was offered under three part numbers 14000801, 14000802 or14001301. Although there was no difference in the Sound Block A board itself, this was done as a result of the K250s in the field. Older K250s did not have a series of modifications to the CGP board required for Sound Block A. For these units, Kurzweil offered kit part number 14000801. This included an updated CGP board as well as the Sound Block A board. The old CGP was to be returned to Kurzweil or the customer was invoiced for the board. Part number 14000802 was used for customers who sent in their CGP board to be updated at Kurzweil. Once the update was completed Kurzweil returned the CGP board with a Sound Block A board attached. This update to the CGP board was done free of charge. Part number 14001301 was just the Sound Block A board sent to be installed on CGP boards that did not require any modification.

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The Sound Block A board is mounted on the CGP board. If you look at a CGP board installed in the K250, you will notice a long white connector (47A) mounted on the board in the lower left hand quarter of the board. The Sound Block A board is plugged into this connector and mounting hardware is installed to secure it.

How to know if the CGP board is ready for the addition of the Sound Block A board? Check in the vicinity of the long white connector (47A) located in the lower left hand quarter of the CGP board. If this board has been modified to accept a Sound Block A board, you will notice some rework wiring coming from U126, U134 and U149, to name a few. This wiring will begin at these locations and encircle the white connector and end at locations below.

2.4 - June, 1985--new Kurzweil 250 configurations

Part No. 10001601--Basic unit, no sampling or sound block Part No. 10001701--Full unit, w/Sound Block A Part No. 10001801--Advanced Sampling, w/Sampling and Sound Block A

Note: These units contained the Ram Sequencer Expansion option as standard.

2.5 - August, 1985--Kurzweil 250X introduced

Part No. 10001901--Basic unit, no sampling or sound block Part No. 10002001--Full unit, w/Sound Block A Part No. 10002101--Advanced Sampling, w/Sampling and Sound Block A

Note: These units also contained the Ram Sequencer Expansion option as standard.

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At introduction, the Kurzweil 250X was introduced with Version 2.1 software. This software did not support sampling and sampling could not be used with the K250X until Version 2.2, which will be discussed later. An important difference between the K250 and the K250X is that every K250X produced had its program EPROMs contained in 256K EPROMs. The Kurzweil 250 used 128K EPROMs at that time.

2.6 - October, 1985

Version 2.2 introduced--free update 50kHz Sound Modeling Program--purchased option 50kHz Sound Modeling Upgrade Kit--purchased upgrade

Version 2 software was now obsolete. Version 2.2 supported 50kHz sampling and corrected some known bugs in Version 2. It was a free update, but was only offered to customers who were experiencing problems or who were purchasing a Sound Modeling Program or a 50kHz Upgrade Kit. One thing to note is that if a customer had a unit with 25kHz sampling and wanted Version 2.2, the unit had to be upgraded to 50kHz. The Version 2.2 EPROMs should be the following:

82051021    U54        82051121    U38
82051221    U53        82051321    U37
82051421    U52        82051521    U36
82051621    U51        82051721    U35

The 50kHz Sound Modeling Program was offered in the same way the 25kHz options were offered. Kurzweil continued to offer two kits (with or without Audio board) for purchase. The modifications to the K250 were basically the same as those outlined in the installation procedures for the 25kHz upgrade. However, not all modifications were necessary for units recently produced.

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The 50kHz Sound Modeling Upgrade Kit required that the K250 had Version 2.2 installed. The sampling EPROMs on the CPU board needed to be replaced with part no. 82000412 at U25, part no. 82000413 at U40, part no. 82000414 at U26; and part no. 82000415 at U41. The A/D converter at U50 on the Channel board must be replaced with part no. 63001701 and one cut and one jump is required.

Note: When installing the 50kHz Sound Modeling Program or the 50kHz Upgrade kit, the cut and jump to the Channel board is not necessary on the K250X. Every K250X produced had this modification already performed. Also, modifications to the CGP board required for Sound Block A and sampling are not required.

2.7 - March, 1986

Version 3.1 software--purchased option Enhanced Resident Sound Block--purchased option (new CGP) Sound Block B (Rock Block)

The installation of Version 3.1 in K250s required cuts and jumps to the CPU board. These modifications were required to add the additional 4K memory and to reconfigure the board for the installation of 256K EPROM (CPU until this point used 128K EPROMs).

Version 3.1 also required units with 25kHz sampling to be upgraded to 50kHz sampling. Because Version 3.1 supported a 12K sequencer memory, units with only 4K had to be upgraded to 8K. The installation of Version 3.1 involves installing the Version 3.1 EPROMs at the following locations:

82101401    U54        82101501    U38
82101601    U53        82101701    U37
82101801    U52        82101901    U36
82090401*   U51        82090501*   U35

*50kHz Sound Modeling EPROM locations

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Note: The Kurzweil 250X CPU board does not require any cut or jump. It is only necessary to remove the Version 2.1 or 2.2 EPROMs and install the Version 3 EPROMs.

The installation of the Enhanced Resident Sound Block requires Version 3.1. For units with Sound Block A boards, the Sound Block A board could be reinstalled on the Enhanced Resident Sound Block. Or, if the Sound Block A chips were socketed; they could be removed and installed on the Enhanced Resident Sound Block in the empty sockets designated for the sound block.

When installing the Enhanced Resident Sound Block, be sure to remove the 20 DRAMs, if present, located on the old CGP and reinstall them on the Enhanced Resident Sound Block. Failure to do so will render sampling useless.

Sound Block B may be installed on a Sound Block A board or the Enhanced Resident Sound Block. If Sound Block B is being installed on a Sound Block A board be sure that there are sockets for the chips. These sockets are supplied with the kit if ordered properly. Kurzweil does not recommend that these chips are soldered into the Sound Block A board. Therefore, when ordering a Sound Block B, please specify if it will be installed in a Sound Block A board. If Sound Block B is being installed in a Enhanced Resident Sound Block it is only necessary to plug the chips in the sockets specified.

Note: When updating units to Version 3.1 without sampling, be sure to remove the old Version 2 or 2.2 EPROMs at locations U35 and U51.

2.8 - August, 1986

Version 3.2 software--purchased option QLS--purchased option Sound Block C (Classical Block)--purchased option

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To install Version 3.2 in units that currently have Version 3.1, no modifications will be required to the CPU board. Simply remove the Version 3.1 EPROMs and install Version 3.2. To install Version 3.2 in units with software levels earlier than Version 3.1, the CPU board will require modification as mentioned in the description of Version 3.1. The Version 3.2 EPROMs should be installed in the following locations:

82102001    U54,    82102101    U38
82102201    U53     82102301    U37
82102401    U52     82102501    U36
82090701*   U51     82090801*   U35

*50kHz Sound Modeling EPROM locations

Version 3.2 is required to install QLS. QLS contains a p.c. board, Macintosh disk and cable. The installation of the QLS p.c. board requires removing the parallel port chip in location U108 on the CPU board. The QLS p.c. board is plugged into the empty socket at U108 and supported with mounting hardware. It is a fairly simple installation, however, the pins on the solder side of the QLS p.c. board may break off if bent.

Sound Block C may be installed on a Sound Block A board or the Enhanced Resident Sound Block. Note: if the unit currently has a Sound Block A board with Sound Block B installed it is not possible to add Sound Block C. If Sound Block C is being installed on a Sound Block A board be sure that there are sockets for the chips. These sockets are supplied with the kit if ordered properly. Kurzweil does not recommend that these chips are soldered into the Sound Block A board. Therefore, when ordering a Sound Block C, please specify if it will be installed in a Sound Block A board. If Sound Block C is being installed in a Enhanced Resident Sound Block, it is only necessary to plug the chips in the sockets specified.

Note: QLS may not be installed in units that do not have sampling.

Note: When updating units to Version 3.2 without sampling, be sure to remove the old Version 2 or 2.2 EPROMs at locations U35 and U51.

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2.9 - December, 1986

Version 4 software--purchased option Superam I or Superam II--purchased option* *requires Enhanced Resident Sound Block Sound Block D (Brass Block)--purchased option

To install Version 4 in units that currently have Version 3.1 or 3.2, no modifications will be required to the CPU board. Simply remove the Version 3.1 or 3.2 EPROMs and install Version 4. To install Version 4 in units with software levels earlier than Version 3.1 or 3.2, the CPU board will require modification as mentioned in the description of Version 3.1. The Version 4 EPROMs should be installed in the following locations:

82102601    U54        82102701    U38
82102801    U53        82102901    U37
82103001    U52        82103101    U36
82091001*   U51        82091101*   U35

*50kHz Sound Modeling EPROM locations

Version 4 is required to install Superam. Superam is installed on the CGP board. It requires the Enhanced Resident Sound Block (new CGP). Superam is installed by adding mounting hardware to the CGP and inserting connecting cables from the Superam board into the CGP board.

Sound Block D may be installed on a Sound Block A board or the Enhanced Resident Sound Block. Note: if the unit currently has a Sound Block A board with Sound Blocks B or C installed it is not possible to add Sound Block D. If Sound Block D is being installed on a Sound Block A board be sure that there are sockets for the chips. These sockets are no longer supplied with the Sound Block D kit, please order separately from Kurzweil. Kurzweil does not recommend that these chips are soldered into the Sound Block A board. Therefore, when ordering a Sound Block D, please specify if it will be installed in a Sound Block A board. If Sound Block D is being installed in an Enhanced Resident Sound Block, it is only necessary to plug the chips in the sockets specified.

Note: When updating units to Version 4 without sampling, be

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sure to remove the old Version 2 or 2.2 EPROMs at locations U35 and U51.

2.10 - March, 1987--RMX introduced

Part No. 10004701--RMX 225, old-style CGP and Sound Blocks A and B Part No. 10004801--RMX 225, new-style CGP, no Sound Blocks Part No. 10004801--RMX 250, new style CGP and Sound Blocks A through D Note: These also contained the RAM Sequencer Expansion, 50kHZ Sound Modeling Program and QLS as standard.

2.11 - April, 1987

Version 4.1 software--purchased option

To install Version 4.1 in units that currently have Version 3.1, 3.2 or V4; no modifications will be required to the CPU board. Simply remove the Version 3.1, 3.2 or V4 EPROMs and install Version 4. To install Version 4.1 in units with software levels earlier than Version 3.1, 3.2 or 4, the CPU board will require modification as mentioned in the description of Version 3.1. The Version 4.1 EPROMs should be installed in the following locations:

82103201    U54        82103301    U38
82103401    U53        82103501    U37
82103601    U52        82103701    U36
82091201*   U51        82091301*   U35

*50kHz Sound Modeling EPROM locations

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2.12 - October, 1987

Version 5 software--purchased option Separate Outputs (S/O)--purchased option* *RMX version of S/O available as of June 1988.

To install Version 5 in units that currently have Version 4.2, 4.1, 4.0, 3.2 or 3.1; no modifications will be required to the CPU board. Simply remove the current version EPROMs and install Version 5. To install Version 5 in units with software levels earlier than versions mentioned above, the CPU board will require modification as mentioned in the description of Version 3.1. The Version 5 EPROMs should be installed in the following locations:

82104401    U54        82104501    U38
82104601    U53        82104701    U37
82104801    U52        82104901    U36
82091801*   U51        82091901*   U35

*50kHz Sound Modeling EPROM locations

Version 5 is required to install S/O. S/O for the K250 contains 2 p.c. boards, Macintosh disk, a new rear panel and cable assembly. The S/O kit for the RMX contains a p.c. board, Macintosh disk, 12-output box and cable assembly.

2.13 - September, 1988

Version 6--purchased option RAM cartridge--purchased option RAM cartridge adapter--purchased option

To install Version 6 in units that currently have Version 5.0 4.2, 4.1, 4.0, 3.2 or 3.1; no modifications will be required to the CPU board. Simply remove the current version EPROMs and install Version 6. To install Version 6 in units with software levels earlier than versions mentioned above, the CPU board will require modification as mentioned in the description of Version 3.1. The Version 6 EPROMs should be installed in the following locations:

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82105001        U54        82105101        U38
82105201        U53        82105301        U37
82105401        U52        82105501        U36
82092001*       U51        82093001*       U35

*50kHz Sound Modeling ERPROM locations

The RAM cartridge is external to the unit and is only available for the K250. The RAM cartridge adapter is installed in the K250 on the CGP board.

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2.14 - SOFTWARE VERSIONS VERSUS OPTIONS AVAILABLE

2.14.1 - Version 2

Sound Block A Ram Sequencer Expansion (8K) 25kHz Sound Modeling Program MacAttach

-optional -optional -optional -optional

2.14.2 - Version 2.2

Sound Block A Ram Sequencer Expansion (8K) 50kHz Sound Modeling Program MacAttach

-optional -optional -optional* -optional

*50kHz sampling required for Version 2.2.

2.14.3 - Version 3.1

Sound Block A Sound Block B (Rock Block) Sound Block C (Classical Block) Sound Block D (Brass Block) Enhanced Resident Sound Block 50kHz Sound Modeling Program Ram Sequencer Expansion (8K) MacAttach

-optional* -optional* -optional* -optional* -optional* -optional -required** -optional

*Units with Sound Block A boards may have either Sound Block B or C added. Should a customer desire to add Sound Block B and C, the customer would have to have the Enhanced Resident Sound Block installed as there is only room for one additional sound block to the Sound Block A board.

**The Ram Sequencer Expansion bringing the unit from a 4K sequencer memory to 8K sequencer memory is required with the installation of Version 3.1; because version 3.1 brings the sequencer memory to 12K.

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Note: The Enhanced Resident Sound Block can only be installed in units with Version 3.1 software or better. Therefore units that currently have Version 2 or 2.2 must be updated when ordering the Enhanced Resident Sound Block.

Note: When installing the Enhanced Resident Sound Block in units with sampling, be sure to remove the 20 DRAMs from the old CGP and reinstall them in the Enhanced Sound Block. If the unit has a Sound Block A board with the 10 Sound Block A chips socketed, the chips may be removed and installed in the Enhanced Resident Sound Block (see Enhanced Resident Sound Block Configuration list).

2.14.4 - Version 3.2

Sound Block A -optional* Sound Block B (Rock Block) -optional* Sound Block C (Classical Block) -optional* Enhanced Resident Sound Block -optional* 50kHz Sound Modeling Program Ram Sequencer Expansion (8K) -required** QLS (Quick Load System) -optional*** MacAttach

*Units with Sound Block A boards may have either Sound Block B, C or D added. Should a customer desire to add Sound Block B, C or D the customer would have to have the Enhanced Resident Sound Block installed as there is only room for one additional sound block to the Sound Block A board.

***QLS may only be installed in units with sampling.

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Note: The Enhanced Resident Sound Block can only be installed in units with Version 3.1 or better. Therefore units that currently have Version 2 or 2.2 must be updated when ordering the Enhanced Resident Sound Block.

2.14.5 - Version 4 & 4.1

Sound Block A Sound Block B (Rock Block) Sound Block C (Classical Block) Sound Block D (Brass Block) Enhanced Resident Sound Block 50kHz Sound Modeling Program Ram Sequencer Expansion (8K) QLS (Quick Load System) MacAttach Superam I or Superam II

-optional* -optional* -optional* -optional* -optional* -required** -optional*** -optional

***QLS may only be installed in units with sampling.

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2.14.6 - Version 5

Sound Block A -optional* Sound Block B (Rock Block) -optional* Sound Block C (Classical Block) -optional* Sound Block D (Brass Block) -optional* Enhanced Resident Sound Block -optional* 50kHz Sound Modeling Program Ram Sequencer Expansion (8K) -required** QLS (Quick Load System) -optional*** MacAttach Superam I or Superam II -optional Separate Outputs -optional

***QLS may only be installed in units with sampling.

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Note: When installing the Enhanced Resident Sound Block in units with sampling, be sure to remove the 20 DRAMs from the old CCP and reinstall them in the Enhanced Sound Block. If the unit has a Sound Block A board with the 10 Sound Block A chips socketed, the chips may be removed and installed in the Enhanced Resident Sound Block (see Enhanced Resident Sound Block Configuration list).

2.14.7 - Version 6

Sound Block A -optional* Sound Block B (Rock Block) -optional* Sound Block C (Classical Block) -optional* Sound Block D (Brass Block) -optional* Enhanced Resident Sound Block -optional* 50kHz Sound Modeling Program Ram Sequencer Expansion (8K) -required** QLS (Quick Load System) -optional*** MacAttach -obsolete***** Superam I or Superam II -optional Separate Outputs -optional RAM Cartridge and Adapter -required****

***QLS may only be installed in units with sampling.

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****Version 6 is required to use the RAM Cartridge in the K250.

*****MacAttach is no longer available when the K250 is upgraded to Version 6.

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2.15 - SOUND BLOCK POSITIONING FOR ENHANCED RESIDENT SOUND BLOCK

Sound Block A positioning table with KMSI Part Numbers and Locations

Sound Block B positioning table with KMSI Part Numbers and Locations

Sound Block C positioning table with KMSI Part Numbers and Locations

Sound Block A - Part Number:

KMSI P/N	Description	Qty	Ref. Des.
82018001	Sound Block A	1	U85
82018101	Sound Block A	1	U84
82018201	Sound Block A	1	U83
82018301	Sound Block A	1	U82
82018401	Sound Block A	1	U80
82018501	Sound Block A	1	U79
82018601	Sound Block A	1	U78
82018701	Sound Block A	1	U77
82018801	Sound Block A	1	U86
82018901	Sound Block A	1	U81

Sound Block B - Part Number:

KMSI P/N	Description	Qty	Ref. Des.
82019001	Sound Block B	1	U65
82019101	Sound Block B	1	U64
82019201	Sound Block B	1	U63
82019301	Sound Block B	1	U62
82019401	Sound Block B	1	U60
82019501	Sound Block B	1	U59
82019601	Sound Block B	1	U58
82019701	Sound Block B	1	U57
82019801	Sound Block B	1	U66
82019901	Sound Block B	1	U61

Sound Block C - Part Number:

KMSI P/N	Description	Qty	Ref. Des.
82022001	Sound Block C	1	U47
82022101	Sound Block C	1	U46
82022201	Sound Block C	1	U45
82022301	Sound Block C	1	U44
82022401	Sound Block C	1	U43
82022501	Sound Block C	1	U42
82022601	Sound Block C	1	U41
82022701	Sound Block C	1	U40
82022801	Sound Block C	1	U39
82022901	Sound Block C	1	U38

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Sound Block D

82023001 82023101 82023201 82023301 82023401 82023501 82023601 82023701 82023801 82023901

U20 U19 U18 U17 U16 U15 U14 U13 U12 U11

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2.16 - OPTIONS VERSUS K250 CONFIGURATION

OPTIONS VERSUS K250 CONFIGURATION TABLE

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