Akai S1000 / S1100 samplers

On Tue, 2008-01-22 at 00:13 +0000, Matthew O'Donnell wrote:

> I've also got an S950 that freezes up if it's not used - so 30 seconds
> after I power it up, it'll freeze and not accept any input.  If I give
> it something to think about, it'll stay alive for a bit longer, but
> not long enough to do anything useful. 
> It seems as if the RAM's corrupt; does anyone have a suggestion?  Is
> the RAM replaceable?

If the RAM was damaged it would be more likely to just fail to work at
all, or work perfectly but with garbled sound (probably only at one
point in the sample).

The RAM is replaceable, but maybe not without special tools.  If it's
surface-mount it's especially fiddly.  If it's socketed it's easy but
tedious - you need to heat up each pin and use a solder sucker to suck
the molten solder from the joint and make sure it's completely free of
the copper through-hole tube, for *every single pin*.  If it's stuck at
all, you'll pull the through-hole plating out with the pin, which isn't
good.  On double-sided boards you can get away with bridging wires to
where the pin is supposed to connect to, but on more sophisticated
equipment there are tracks sandwiched within the fibreglass that you
can't get at.

The first thing I'd look at is the power supply.  I haven't had
specifically an S950 apart, but I'd suspect it uses a linear power
supply, like nearly everything of that age (big transformer, big
smoothing caps, big regulator heatsinks).  Often you'll be lucky enough
to find that the voltages are marked on the board near the terminals, or
near test points.  Check that they're all within expected limits -
you'll probably find at least +5V, +12V and -12V (or maybe 15V).  The
big smoothing capacitors dry out and lose capacitance, which means they
no longer smooth the mains ripple so well, which as you can imagine can
cause all kinds of mayhem.  They usually get worse as they warm up,
after about five minutes.

Gordon