Re: AY emulation testing
Posted: Thu Oct 11, 2018 9:29 am
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I have the ZIP for version 1.01b (09/26/2017) https://send.firefox.com/download/ac766 ... DYGRfycSrQ
I doubt it. Although I’m not following the Fuse development process very closely, I don’t think the sound engine has undergone any major (or even minor) rewrites in the past few releases. For the record, I did run the test in v1.5.5, though. I also used Audio Hijack to capture the audio, thus taking any potential artifacts created by the DAC/ADC/cable out of the equation. (Not that they would have had any appreciable or measurable effect in this instance, anyway.)
There you have Spectramine version 1.03b https://yadi.sk/d/Mz2J8P3vMuz3vwdruellan wrote: ↑Thu Oct 11, 2018 12:02 pmI have the ZIP for version 1.01b (09/26/2017) https://send.firefox.com/download/ac766 ... DYGRfycSrQ
I don't know - it's very much what I would expect from Fuse's stronger filters being enabled.
The most direct way is to use the movie recording feature and extract the sound with fmfconv.Ast A. Moore wrote: ↑Thu Oct 11, 2018 12:17 pmI doubt it. Although I’m not following the Fuse development process very closely, I don’t think the sound engine has undergone any major (or even minor) rewrites in the past few releases. For the record, I did run the test in v1.5.5, though. I also used Audio Hijack to capture the audio, thus taking any potential artifacts created by the DAC/ADC/cable out of the equation. (Not that they would have had any appreciable or measurable effect in this instance, anyway.)
Oh, this is interesting!Fred wrote: ↑Thu Oct 11, 2018 2:39 pm Fuse did change the noise handling in 2012 for version 1.1.0 based on the investigation from this WoS thread: https://www.worldofspectrum.org/forums/ ... ion/39644/
The amplitude should remain more or less the same. This is from my Toast Rack:Pegaz wrote: ↑Thu Oct 11, 2018 5:13 pm For most emulators I have tried with noise.tap file, the noise goes from silent to louder in several visible steps.
Only SpecEmu and Spin have a smooth noise transition but it looks like the sound level is the same from the beginning to the end.
Which of these two cases is closer to the real hardware?
Yeah, that would be a bad thing to do.
This would be caused by filtering on those frequencies - you can see the difference in Fuse when you turn filtering on and off.Ast A. Moore wrote: ↑Thu Oct 11, 2018 6:10 pmThe amplitude should remain more or less the same. This is from my Toast Rack:Pegaz wrote: ↑Thu Oct 11, 2018 5:13 pm For most emulators I have tried with noise.tap file, the noise goes from silent to louder in several visible steps.
Only SpecEmu and Spin have a smooth noise transition but it looks like the sound level is the same from the beginning to the end.
Which of these two cases is closer to the real hardware?
Fuse manual wrote: This option allows the emulation of the sound output system to be modified. Different choices of speaker limit the bass and treble response that can be produced from the machine. Choose between a “TV” type speaker and a small beeper type speaker that significantly limits bass and treble response or Unfiltered for the full frequency range like from the MIC output.
I completely agree.djnzx48 wrote: ↑Fri Oct 12, 2018 3:04 am Yeah, I agree that targeting the actual machine is preferable. The reality is though that not everyone owns real Spectrums, and many people are forced to use emulators as their only option. Personally I'd like to write programs for platforms that people will run them on, and I'd say Spin, SpecEmu and Spectaculator together probably make up the majority of emulators in use, without considering clones.
Even if you ignore emulators you still have to deal with compatibility issues, such as the contended memory banks being different on the +2A/+3. I know emulators aren't official Spectrum models, but they're in wide use so it's reasonable to want to support them.
And it's not just a binary decision. You can develop for the Spectrum primarily but still have emulation/additional hardware in mind, for example with ULAplus.
Sure. Perhaps, I didn’t express myself clearly. I didn’t mean to say you should go out of your way to write software that will only work properly on real hardware. Quite the opposite, in my book, it would be a mistake to go out of your way to write software that will only work properly on a particular emulator, even if it happens to be the most popular emulator.djnzx48 wrote: ↑Fri Oct 12, 2018 3:04 am Yeah, I agree that targeting the actual machine is preferable. The reality is though that not everyone owns real Spectrums, and many people are forced to use emulators as their only option. Personally I'd like to write programs for platforms that people will run them on, and I'd say Spin, SpecEmu and Spectaculator together probably make up the majority of emulators in use, without considering clones.
Even if you ignore emulators you still have to deal with compatibility issues, such as the contended memory banks being different on the +2A/+3. I know emulators aren't official Spectrum models, but they're in wide use so it's reasonable to want to support them.
And it's not just a binary decision. You can develop for the Spectrum primarily but still have emulation/additional hardware in mind, for example with ULAplus.
Yes, but what do those emulators actually emulate? The Spectrum or the emulator author’s idea of what the Spectrum should have been like? I’m all for the preservation of the Spectrum. (I doubt many people will share our passion to the same degree it after our generation finally kicks the bucket, though.) But let’s preserve the actual Spectrum, to the best of our abilities. While the actual machines still run and while the people who understand, or can figure out, how they work are still around.Pegaz wrote: ↑Fri Oct 12, 2018 11:10 am Emulators are very important and the best of them already behave practically as real Spectrum.
Their benefits will be even greater in the future, as there will be less and less working Spectrum around.
For me, every Spectrum is equally important , whether its based on emulator, fpga or some other non-original hardware.
Otherwise, even Amstrad models might not be considered as original hardware too.
With the emulators, Spectrum will drastically extend its life span and user base, without them it will only become just a piece of hardware in the museum.
Most, if not all, PC emulators support 50hz, and I'd say most screens support that refresh-rate as well. I have a cheap ASUS a couple of years old and it handles 50hz just fine.Ast A. Moore wrote: ↑Fri Oct 12, 2018 2:25 pm 8. No emulator is, of course, capable of displaying the Spectrum output at its native 50 fps. This isn’t the fault of any particular emulator, naturally, but rather the systems they runs on: most modern computers are locked to a 60 Hz refresh rate.
Thank you! That was a very enlightening post.
That's not exactly true, my friend...Ast A. Moore wrote: 8. No emulator is, of course, capable of displaying the Spectrum output at its native 50 fps. This isn’t the fault of any particular emulator, naturally, but rather the systems they runs on: most modern computers are locked to a 60 Hz refresh rate.
Yes, I also came to a similar conclusion.zx81 wrote: ↑Sat Oct 13, 2018 11:15 am
In theory, you can configure a HDMI mode with exact frequencies, but isn't easy to generate the needed numbers and can depend a bit of every TV-set, so I don't want to try this way. After all, the interlaced modes are "emulated" by modern TV-sets, and every model handles this with his own method.
I'm curious about the AY quality in ZXBaremulator, if somebody can try...