Quadro - quad system for ZX Spectrum based on AY3-8910.

QUAD SYSTEM FOR "ZX-SPECTRUM"

 Musical capabilities of the coprocessor
AY3-8910 (AY3-8912) in computer
"ZX-SPECTRUM" is now far from satisfied
everyone. Attempts are being made to switch to CO-
VOX, but high memory and speed costs
nullify the improvement in sound quality
nia.
 Quad sound looks like a compromise with
additional musical coprocessor
rum. At the same time, the composer receives his
disposal of 6 independent musical
channels instead of three!
 The proposed quad system contains
2 additional ports with #AFFD addresses
(45053) and #EFFD (61437) for connection
additional musical co-process
sora.
 Port #AFFD corresponds to performance
our functions remain the same port #BFFD, and the port
#EFFD - port #FFFD.

 In such a system compatibility remains
with conventional stereo AY melodies
Yami, i.e. previously written melodies will be
sound as before from the front (pe-
middle) speakers. With quad music, the sound is
will also appear in the side columns.
 Surround sound, echo reverberation,
rotating sound, frequency division
channels - these and other effects are easily realized
are formed in a quad system, the sound is obtained
It's juicy, close to a concert hall.

CONVENTIONAL SYMBOLS on the diagram of the quadrapri-
rates:

1 / Input signals are located on the left and
are taken from the microprobe pins of the same name
processor Z80 or from system contacts
tires:
       A12=Z80:2-WR=Z80:22
       A15=Z80:5 -IPRQ=Z80:20
       A1=Z80:31 -M1=Z80:27
       A14=Z80:4

2 / Output signals are located on the right
and arrive at the same conclusions of the previous
him (BDIR ,BC1) and new (BDIR╙ , BC1╙)
music coprocessors AY3-8910/12:
      BDIR=AY3-8910:27 = AY3-8912:18
       BC1=AY3-8910:29 = AY3-8912:20

3 / The remaining conclusions of the two musical
coprocessors are parallelized, of course
except for audio outputs A, B, C. Signals
left and right stereo channels of the previous
coprocessor are fed to the front (pe
front) speakers, and the stereo channels are new
coprocessor are fed to the rear (side-
high) columns.

4 / Sign "-" before the signal designation
means low active level.

5 / Quad box requires 3 mic
circuit diagrams of the K555 or KR1533 series: ID7, LA3,
LN1.

Power supply for microcircuits:
     ID7:16=LA3:14=LN1:14=+5V;
     ID7:8=LA3:7=LN1:7=0V.
                                RSM-SOFT

For all questions related to quadrasis-
subject, please contact: 250033,
                           Ukraine,
                         Chernigov-33,
                         PO Box 1772

            CODER'S COMMENTS

 The advantages of this system are obvious.
With a slight increase in the occupied
memory melody (maximum twice as much
conventional) and economical use of machines -
long time, the sound quality becomes
much higher.
 To remake any melodyunder the second
coprocessor, just change the values
ports in PLAYER.
 At this stage there is no complete
valuable music editor for 6 channels, but
The application includes the "QUADRA" program
CONVERTER", which allows redistribution -
transfer music from regular AY to additional
tel.
 Playing two melodies in parallel,
QUADRA and regular, you can get six-
naal sound.
 Of course, this way of making music
inconvenient, but if this development is semi-
cheat support, we can talk about na-
QUADRA MUSIC EDITOR's writings.
 By the way, EVOLVER of DMS/RUSH, writes this
hour ULTIMATE FM TRACKER. I think that ne-
it will not be possible to remake it for 6 channels
very difficult.

 For questions related to software support
for support for quad system, please contact
to me (VIATOR).

                   VIATOR of AVALON/RUSH