Further Testing; Testing 48Khz; Figure 8 - 48Khz Test - Alesis QS Series Service Manual

3.20 Further Testing

Naturally it is a good idea to actually play the keyboard. Be sure to check that pitch and
velocity scaling sound normal. It's also important to check the Aftertouch to ensure it's function.
Note that in the QS8 it is important to check the Aftertouch of white and black keys separately
as each of these key sets has it's own Aftertouch cable.
While the self test will pick up most circuit errors, MIDI should still be tested in both send
and receive. This can be done 3 ways:
Record and playback from a MIDI Sequencer
Save and load Sys-ex data from a MIDI Librarian or DataDisk.
Use a second keyboard to send trigger notes to the unit under test.
Also test that key presses from the unit under test trigger notes on
the other keyboard or an extra module.
If at all possible, the PC/MAC Serial connector should be tested similarly, as well as all
other I/O type circuitry such as 48KHz, PCMCIA, and optical (with the use of an ADAT
Multitrack).

3.21 Testing 48KHz

Obtain an ADAT-XT or a classic ADAT and a BRC. Connect the sync cable from the
ADAT to the BRC. Connect a BNC cable from the BRC's 48K OUT to the QS's 48K IN.
Connect a fiber optic cable from the QS's OPTICAL OUT to the ADAT's OPTICAL IN. Finally
connect the ADAT's analog outputs 1 and 2 to an amplifier and speakers or headphones as
shown in Figure 8. Make sure the BRC syncs to the ADAT. Press the DIG IN and ALL INPUT
MONITOR on the ADAT-XT or BRC.
Turn on the QS under test's 48K IN ON (under Global button).
Change the Pitch control on the ADAT-XT or BRC from 000 to -300. Play the QS and
listen for a change in pitch. Also, play the DEMO and monitor the QS's audio from the ADAT's
analog outputs 1 and 2. The audio should be clean and undistorted for the above. In this event,
pass the unit. If the unit has a clipping noise after the 48K IN has been turned on, fail the unit.
Alesis QS Series Keyboards Service Manual V1.00

Figure 8 - 48KHz Test

22 11/19/06