I composed a small number of Amiga tracker modules at around the turn of the 1990s, one of which even enjoyed some popularity. These were made first and foremost for my personal amusement — for exploring music creation and sequencing on a computer — but they also ended up being used in some demoscene productions.
My tools of choice for sequencing them were, ...
If (and only if) your audio player is battery powered, and your Spectrum is the 48K or 128K toastrack model, try the following procedure, intended to boost the volume of your wave signal, as seen by the Spectrum EAR circuitry:
Get one of these audio cables. They are very common. And yes, they are stereo.
Why do we need it to be stereo? The trick is that ...
In theory that would have been possible from the very start. After all, music doesn't need much bandwidth (*1), especially when using synthesized form like with a sound chip such as the SID.
In reality the software structure of (most) machines in the 70s and 80s would not support this. They were single program, single tasking machines and the OS was not ...
The four main ways were:
you knew someone with the sampling card or sampler (many of samplers had the capability to sample sound in CD quality and save it to floppy disk).
you bought some kind of "sample bank"
you simply grabbed sounds from other MODs
you generated fully artificial sound by math algorithms and computed sample data (e.g. simple ...
On the generic early-nineties x86 systems I'm familiar with at least, redbook CD audio playback on IDE CD-ROM drives is asynchronous and autonomous. The drive would connect to the sound card through a four-pin stereo audio connector to provide CD audio as another audio source to the mixer.
You could use a CD music player program to control track selection ...
It was a DOS-Windows 3.x and DOS-Windows 9x/ME thing. It was a driver named speaker.drv, written by Microsoft. It turned off interrupts for significant periods of time, which caused I/O problems with other devices but which was inherent in the nature of the hardware. It came in a self-extracting archive named speak.exe, and could be found on the companion ...
MOD is the file extension for SoundTracker modules. SoundTracker and its successors (NoiseTracker and ProTracker predominantly, although there are other derivatives) are sequencers, and load and save files in this format. It was originally designed for games and demo programmers - assembly code to play back the modules was commonly available and worked ...
As the sound channels had independent linear 64-step volume control (6 bits + mute setting), by calibration and splitting sample bits for one 14bit waveform across two channels, two-channel 14bit (stereo) sound could in principle be improvised using all 4 channels.
This would be done by playing
A coarse part of the waveform generated from the higher 8 bits ...
Short answer: It's a holdover from the Warez scene, and more specifically around the time of the Commodore Amiga when pirates had ready access to music software.
Back in the day (and less often nowadays), pirates "signed" cracked software with their name or emblem or something to that effect. As more and more pirates entered the scene and piracy became more ...
According to the very same link you provided:
To perform this feat, Oktalyzer loaded eight channels in memory, mixed
them in real time down to four channels, and sent the result to the
Amiga sound chip. This was a processor-intensive task which degraded
sound quality, but was more than made up for with doubled channels.
Oktalyzer could also be run ...
I've confirmed that mcleod_ideafix's method is reliable for regular tape images. Here is a shell script to do (effectively) the same thing:
# wav2differential.sh - convert mono game tape audio to 2× stereo
# usage: wav2differential.sh infile.wav
# (creates infile-differential.wav)
# scruss - 2016-06-07
# method by ‘mcleod_ideafix’; ...
You need to use OpenMSX, and get the system ROMs for the machine in question. Then run OpenMSX, set the machine to the FS-A1WSX. There's a little menu button at the top left of the OpenMSX window. In there, set your tape to the WAV file. Then:
10 M$ = "E4E8O3G16G32R32G2G4R4O4C8D8E8F8G2G8F8E8F4E8D8E4D8C4"
20 PLAY M$+M$
The listing above is the content of ...
None of the GameBoy series machine has a Z80, but instead a Sharp LR35902, which runs a "GBZ80" instruction set, which is if I'm not mistaking similar but incompatible with the genuine Z80, as it lacks the two registers sets (much like the 8080) and other instructions. Just like the 2A03 in the NES, the CPU is in the same chip as the sound generation ...
Did they really plug a synthesizer's audio output into a line input of a sound card and digitize the analog sound? But were audio cards of the early 90s at all capable of capturing analog audio at reasonable quality?
Samplers existed even for low-end machines. I remember using a sampler on my Amiga 500. It was 8-bit, but so are the .MOD samples, and sample ...
SID6851 specification quotes:
Cut-off frequency variation may occur from chip to chip due to
process variations, and power supply voltage. Capacitor values and
voltage regulation can compensate for these variations
We're talking about a 30-some years old chips, the manufacturing process wasn't very consistent back then, and also MOS was known to ...
The topic mentions PCs but as you mention C64s specifically in the text, I can note that on the C64 it was not uncommon for utility software to have built in music (especially in the tools centered around the needs of the demo scene).
Of course, that is not the same as a general purpose music player.
Music was generally not really made using MIDI or audio ...
The NES cartridge connector does not have expansion sound. However, there's an expansion port on the bottom of the NES which does, although this connector was never used by any commercial games.
JAL's answer describes a mod involving soldering a resistor between pins 3 and 9 of the expansion connector. This actually does work. Pin 3 is the expansion ...
In the case of the Famicom, the extra chip(s) on the cartridge would contain some additional sound generators. The cartridge slot contained a pin that would accept audio from the game cartridge and mix it with the other audio coming from the console and send it all to the TV.
Notice that the ...
The Amiga was the first system where I pulled this off:
It was not streaming music, but listening to so called "MOD"s, small data chunks of samples and instructions how to play them. There is still an alive(?) scene for this. These Mods could be played in the background on Amigas Multitasking OS, while you were doing something else.
If you just ...
The Wikipedia comment is misleading. The Game Boy CPU has several components in one chip, including the Z80-alike CPU core and a sound generator among others. These components may all be in the same chip but they are functionally independent; you don't need the Z80 CPU to be able to produce audio.
The Nintendo DS inherited the Game Boy sound generator ...
[Do over answer]
Based on your clue that an Atari monitor has matching coloured inputs I looked up the Atari 8-bit video connector, compared to the C64:
It is likely you have an Atari lead rather than a Commodore one. So your four signals are intended to be (1) luminance; (2) audio; (3) composite video; (4) chroma where available.
Plugging that cable into ...
Yes, games like Rescue Raiders and Silent Service used interrupts to queue music and sound effects while other things were happening on the screen. Perhaps the best example of the technique is Skyfox, which had music playing during the frenetic dogfight action.
The option to have simultaneous graphics and great sound without cycle-counting was one of the ...
Black-and-white hi-res from the 1040 STE on a VGA monitor should work with a direct connection and no tricky electronics at all (just the adapter cable)
GND 13----X---- GND ---------4 GND
I haven't tested this, so I can't vouch for its authenticity, but one guide claims that soldering a 24k to 56k resistor between pins 3 and 9 of the NES expansion connector will "unlock" additional sound channels.
Note that this only works on the original release with mono audio out.
The problem you have is that most home computers of that era output TV standard signals which VGA is not. As you've mentioned there needs to be some conversion from one standard to the other.
A popular solution that I happen to use is the Gonbes GBS-8200/GBS-8220 boards. They aren't perfect and some people hate them but they are reasonably cheap and I think ...
The good news is the next few steps are easy.
Most (all?) of the MSX emulators include a "virtual tape" that can open a WAV file. openMSX does for sure. It's right in the instructions for the emulator.
I don't know enough about MSX to know if it stored programs as text or in tokenized format, but in either case, once it is loaded you can use the "virtual ...
Check this Spectrum tape interface:
A 'pulse' here is either a mark or a space, so 2 pulses makes a
complete square wave cycle.
Pilot tone: before each block is a sequence of 8063 (header) or 3223
(data) pulses, each of length 2168 T-states.
Sync pulses: the pilot tone is followed by two sync pulses of 667 and
735 T-states resp....
I developed few game on the GBA back in the days and I remember that I looked into using the Z80 but found nothing in the official documentation.
Even if possible, it is an unsupported feature and therefore I doubt that any Nintendo approved game uses it.
You have three problems to overcome:
Separate sync from composite video or CSYNC into H and V to get an RGBHV output.
Upscale/scan double from 15 kHz to the 31 kHz that most VGA monitors accept.
Separate out the audio.
The $89 Ambery 15Khz RGB CGA to VGA RGBHV Converter Scaler is a device that appears to do the first two, but I have no experience with it. ...
Those variable amplitudes looks like electronics problem like failing caps somewhere along the way (recording/playback) or unshielded too long cables or partial remagnetization or even HW bug (some recorders like ELTA have a bug in writing head circuitry that corrupted tapes a bit each time it was played ...)
the correct output should be a rectangular ...