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Akai S1000 / S1100 samplers

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Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU is..

Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU is..

2005-04-07 by taurecords

inside of it - I only do know that the Akai S950 had an Intel
compatible (186 IIRC) processor for the main tasks, would love to know
(and hear) if the Akai S1100 is still based on such a (compatible) CPU
, or is this a completely custom made machine which doesn't run on
anything but custom ASICs ? (From what I've read it includes custom
ASICs, however it seems still somehow unlikely that such a vintage
sampler is completely customized already.. only Ensoniq/Emu did that
efford from the "emulator-4 based "(e4k/e6400,etc) machines on..

The reason why I'm asking is because I want to develop some software
for it - and this would simplify the process tremendeously - I do have
all the necessary tools at home (EPROM burners, logic analyzers,
scopes,etc)

So far I have only snatched this rather low-res picture from the web
of the internals... I suspect (and hope) the rather lengthy chip in
towards the center on the front could be the CPU..

http://home.arcor.de/jfkrecords/akai/aka.jpg


Many thanks for a quick reply in advance,

Cheers

-Jan

Re: Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU

2005-04-07 by formals777

Jan,

Very intersting. Let me know if I can help you with the project. 
The S1100 is based on the NEC V50. This is a 8080 compatible CPU. I do
not know if akai uses it only in 8080 compatibility mode. 


Rgds,

Frank



--- In akaiS1000S1100Samplers@yahoogroups.com, "taurecords"
<TaurusRecords@g...> wrote:
Show quoted textHide quoted text
> 
> inside of it - I only do know that the Akai S950 had an Intel
> compatible (186 IIRC) processor for the main tasks, would love to know
> (and hear) if the Akai S1100 is still based on such a (compatible) CPU
> , or is this a completely custom made machine which doesn't run on
> anything but custom ASICs ? (From what I've read it includes custom
> ASICs, however it seems still somehow unlikely that such a vintage
> sampler is completely customized already.. only Ensoniq/Emu did that
> efford from the "emulator-4 based "(e4k/e6400,etc) machines on..
> 
> The reason why I'm asking is because I want to develop some software
> for it - and this would simplify the process tremendeously - I do have
> all the necessary tools at home (EPROM burners, logic analyzers,
> scopes,etc)
> 
> So far I have only snatched this rather low-res picture from the web
> of the internals... I suspect (and hope) the rather lengthy chip in
> towards the center on the front could be the CPU..
> 
> http://home.arcor.de/jfkrecords/akai/aka.jpg
> 
> 
> Many thanks for a quick reply in advance,
> 
> Cheers
> 
> -Jan

Re: Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU

2005-04-08 by taurecords

Many thanks - that's exactly what I wanted to know - just too bad this
seems to indicate the chip is in a LCC-type case (or PGA).. so
upgrades would be a bit more difficult to manage.

However - I could still try to supply it with some "backup" processors
- maybe abusing the expansion/option card slots, or trying to
piggy-back a module to some locations of the DIL-case-chips, which use
the adress space & the data-bus of the CPU to the most.

I'd love to write some routines for fast,resonance-capable filters,
however - this will require either additional horsepower (in form of
CPUs or DSPs) - or I'll have to stick with "real" analog filter circuits.

Also re-doing the user-interface a bit (for which most likely the V50
is responsible) - and adding some horse-power to this is a goal I want
to achieve.

But first I have to buy a S1100 :-) - I have one offer for 159 bucks -
that seems to be ok.


Cheers
-Jan

--- In akaiS1000S1100Samplers@yahoogroups.com, "formals777"
<wafwaf@p...> wrote:
..The S1100 is based on the NEC V50.

Re: Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU

2005-04-08 by formals777

Jan,

Right, almost all IC's are glued/soldered to the mainboard.
I think that most people are happy with the sound - apart from the
effects and the filter. A more important problem on samplers is that
they are quite difficult to program (the small screen , keys). It
should be nice to have a better interface to program the sampler. The
roland 750 and 760 had an optional CRT/mouse option board. But another
solution could be a small linux embedded webserver in the sampler.
The only thing to know then are the addresses of the subroutines in
the ROMS.
 
The s1100 is a nice sampler to extend because there are so many empty
slots available. You can reach all data adress and control lines from
the bus.

For improvements to the effects and filters a much easier solution is
to buy cheap effects on ebay. BTW: akai has an external filterbank
available. 

Regards,

Frank
amplers@yahoogroups.com, "taurecords" <TaurusRecords@g...> wrote:
> 
> Many thanks - that's exactly what I wanted to know - just too bad this
> seems to indicate the chip is in a LCC-type case (or PGA).. so
> upgrades would be a bit more difficult to manage.
> 
> However - I could still try to supply it with some "backup" processors
> - maybe abusing the expansion/option card slots, or trying to
> piggy-back a module to some locations of the DIL-case-chips, which use
> the adress space & the data-bus of the CPU to the most.
> 
> I'd love to write some routines for fast,resonance-capable filters,
> however - this will require either additional horsepower (in form of
> CPUs or DSPs) - or I'll have to stick with "real" analog filter
circuits.
Show quoted textHide quoted text
> 
> Also re-doing the user-interface a bit (for which most likely the V50
> is responsible) - and adding some horse-power to this is a goal I want
> to achieve.
> 
> But first I have to buy a S1100 :-) - I have one offer for 159 bucks -
> that seems to be ok.
> 
> 
> Cheers
> -Jan
> 
> --- In akaiS1000S1100Samplers@yahoogroups.com, "formals777"
> <wafwaf@p...> wrote:
> ..The S1100 is based on the NEC V50.

Re: Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU

2005-04-25 by taurecords

--- In akaiS1000S1100Samplers@yahoogroups.com, "formals777"  wrote:
1)
>..most people are happy with the sound - apart from the
> effects and the filter. 
..
2)
> The s1100 is a nice sampler to extend because there are so many empty
> slots available. You can reach all data adress and control lines from
> the bus.

3)..a much easier solution is
> to buy cheap effects on ebay. BTW: akai has an external filterbank..

Wow - many thanks - you seem to have an excellent knowledge about this
box, and I figure you've considered something alike too - at least at
one time ?

"My" S1100 finally arrived, and I spent a few days just bend over it &
peeping at the various ICs :) - so far I have downloaded almost all
datasheet for the chips, lacking only the Sony CXD-1211P (which is
there for processing of the digital audio stream anyway - I assume the
AES output that is onboard is it's main task), and the 3 huge custom ICs..

I'll place the datasheets on a webspace to make'em easier to access
for one in need.


1) :) now what's wrong with the effects :-D ? .. ok, but thanks for
the hints & pointing out the experience / general user tendencies -
would've taken several nagging questions of me before I'd know all
what could be improved.


It seems that the effects, from the Motorola 56001 DSP-board, are
stored externally .. I have no datasheet of the 56001 at hand, but I
don't recall an internal ROM as being an option - and there seems to
be nothing on the card (from looking at it - installed - through the
gaps).

I suspect the parameter ROMs, of maybe even the main OS ROMs are the
ones who hold the algorithms - so new effects could be quite easy to
create -- for as long as the DSP power is enough.

If it wouldn't be an effects processor for the sum, I guess I could
even abuse it for filter effects (since Clavia used a stack of them
for their Nord Lead/Lead 2 synthesizers) - but even with the sum - one
could try to enhance it for some filter/wah/auto/dynamic-filter
effects with resonance & distortion.

"unfortunatelly" I just have a Analog Devices AD2181 Devkit - so I
would have to make up the algorithms w/o testing (or use
software-simulation), and later just flash it into a ROM & see how it
would work out.


2) Yes, especially in my one :) - I am lacking the digital I/O card,
and I have only the - in my case - redundant SMPTE card, plus the SCSI
card in the expansion slots.

I already found a cheap source for the appropriate connectors
(2x32pins IIRC), which are luckily industry-standard.


3) Is that a slight sign for telling me that I am "trying to stuff a
mushroom" here :-) ? .. thought that this would still be possible -
and it doesn't seem too hard.. unless the audio-streams don't get
treated exclusively by the custom chips (all signs seem to indicate it
unfortunatelly) - and that the individual, digital audio-streams are
not present/accessible on the option-bus - what would be necessary in
order to mangle each voice individually (with a
filter/effects/compression).

The reason why I'm curious where you've got your knowledge from is
mainly because - I wanted to know whether there are some service
manuals existing - or maybe even programmers/hardware-developers
manuals/documentation available from Akai .. and if either is worth
the money  - I simply assume that all the companies that are
manufacturing memory board, SCSI & digital options haven't really
reverse-engineered all of this..



If someone'd happen to have bought something like a service manual /
developers-guide in the past, and would be knowing a cheap source for
buying these - I'd love to hear something about it.

I do have an Akai-support facility around here in Germany too, but
it's a whole Alesis/Akai/Numark - jointventure - so I am a bit afraid
that there's not much I could get from them for a sampler dating back
to 1991..


I'll poke around on the 3 memory cards I have, of which oddly each
look different  - the machine has 10 MB if I'm not mistaken, and
change my EL foil which's gone south, delivering a nice whining noise
from the inverter-coil :)

You can see my box here - it's the same machine as in the picture
posted before - just now it's mine =)

http://home.arcor.de/jfkrecords/akai/aka.jpg



---------->> What I've just found out about that box:
IC1 = NEC 70216GF - 10 = Nec V50 CPU, 10MHz, integrated DMA,refresh,etc 
IC3 = Standard NEC D72068 GF floppy controller ( 765 alike/standard
PC-type)
IC7 = -- Sanyo LC7891 LCD driver, pretty much a standard too,which uses 
IC14 as character RAM ("video RAM" - if you want so), 2kB SRAM,via 11
addr. lines

IC8 = Sony's "Digital Audio Transmitter" IC.. I believe this is for
dig./SPDIF/AES-EBU output.. could have something to do with the Akai
CDROM format too though ? but very unsure about the latter.

IC9 seems to be a Intel 8255 multip. controller-clone made by Fujitsu
(MB89255A) - responsible for de-/multiplexing I/O to/from the
keyboard/panel controls

IC10 and
IC11 are holding the OS, each a standard 1MBit(128kb) EPROM chip


IC12 and
IC13 = PARAMETER ROMs, whatever that means, each 64kb =512kbits in size

IC18 and
IC19 and
IC20 and
IC21 = 4 DRAM chips -- I assume a buffer, either for the CPU or
digital audio streams...

Connector P125 holds 5volts/gnd/gnd/12volts - so it's most likely the
connector for a HDD (one needs to make a special cable for the
standard HDD connector - or abuse a prong from a standard floppy
connector of a PC -PSU's cable.. - check the lines /voltages though -
could be crossed)


.......// Software:

Well.. I took a look at a S1000's ROMs (after merging them with a tiny
utility) - it seems very Intel compatible in my eyes  -- even the
assembler Akai was using for that OS seems to indicate this, as they
didn't even take the time to remove the redundant macro-strings the
assembler/compiler has put into that binary image (one can clearly
read "AX BX CX".."MOV" "PUSH" "POP",etc) - which looks very 8086'ish,
even though NEC tried to make it look a bit different in their
datasheet :-) but even that was already showing it off..



So -> I'm happy, though the 4 DMA channels which are apparently in use
on IC1 (by looking at the traces on the pins) will probably give me a
headache - and the timers,etc.


Regards
-Jan

Re: Hi - new to this group - and to an Akai S1100 :) - anyone knowing which CPU

2005-04-27 by taurecords

Another thing I must add:
There's another IC that I haven't identified so far yet - it's IC2 (
7730) - I don't know whether the manufacturer's logo supposed to mean
"TEL" .. or something else.

Despite of that  -- I found out some more about the functions of the
custom ASICs - but more on that later :-)

Cheers
-Jan

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