Search found 689 matches

by Ast A. Moore
Fri Oct 12, 2018 7:51 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

Emulator authors (or at least Woody and I, when we were developing SpecEMU and ZXSpin) worked to the best available information at the time . Thank you! That was a very enlightening post. I do want to emphasize (again) that in no way do I try to take a jab at emulator authors. Moreover, and I’ve st...
by Ast A. Moore
Fri Oct 12, 2018 1:25 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

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 a...
by Ast A. Moore
Thu Oct 11, 2018 11:23 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

The clunky part would be having to stick in a menu option for it and getting the user to pick the right one. Yeah, that would be a bad thing to do. Unfortunately, in this day and age of a gazillion of emulators, developers are faced with a choice—to code for the Spectrum or to code for a particular...
by Ast A. Moore
Thu Oct 11, 2018 5:10 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

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 hardwa...
by Ast A. Moore
Thu Oct 11, 2018 5:04 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

Fred wrote:
Thu Oct 11, 2018 1:39 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/
Oh, this is interesting!
by Ast A. Moore
Thu Oct 11, 2018 11:17 am
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

It looks like I'm still on version 1.5.0, so that could have something to do with it? 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...
by Ast A. Moore
Thu Oct 11, 2018 8:29 am
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

djnzx48 wrote:
Thu Oct 11, 2018 8:23 am
Also, I reran the Fuse test making sure the filter was disabled, but still got the same result.
So much for that, then: ;)
Fred wrote:
Thu Oct 11, 2018 5:27 am
There are no platform specific behaviours in this part of Fuse so you don’t need to worry about that :)
by Ast A. Moore
Wed Oct 10, 2018 9:25 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

Could the differences in the Fuse spectrograms be some kind of folding due to aliasing? It's possible it was just a filter though. Possibly. But I’d rerun the test, just to be sure. Also, it might be platform-dependent. I run Fuse on macOS. So Fuse is showing correct behaviour here, and the emulato...
by Ast A. Moore
Wed Oct 10, 2018 9:20 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

Fred wrote:
Wed Oct 10, 2018 8:35 pm
Turn on the filter to get the dc offset addressed in Fuse.
I normally have the “TV speaker” filter on and I only turned it off for the test.
by Ast A. Moore
Wed Oct 10, 2018 6:22 pm
Forum: Emulators
Topic: AY emulation testing
Replies: 35
Views: 720

Re: AY emulation testing

Here’s the spectrogram from my Toast Rack. It’s pretty close to what I get in Fuse. There’s a horizontal line at about 15.5 kHz, though. Not sure what this is. Might be interference from another component, or some weird harmonic. Also note, that there’s no rolloff at higher frequencies. http://i68.t...