MAMEWorld Forums - EmuChat - Re: Spy Hunter bad sound emulation

> I would love to fix it, I have the arcade boards and a computer but nothing else.
>
> Kind of ridiculous on such a big time game and big time emulator, that some one never
> fixed this decades ago, and in their sleep... Just sayin'
>
> Thanks...

I saw your update to the MAMETesters report, and the only "disrespect" here is the fact that you admit that you yourself know absolutely nothing about how to actually fix it, yet you're making these broad assertions about how it can be "fixed in [a developer's] sleep".

You're furthermore talking completely out your ass, which is spread wide for all to see. You loudly assert that "filtering makes no sense", then go on to say that "the sounds are flat out missing most of their composure". Yeah. That's what happens when you play the direct output of a DAC and completely omit any of the analog filtering. For fuck's sake, man, the characteristic "soft brass" tone that characterized a ton of 80's pop is literally just a bunch of filters on top of a pure sawtooth-wave signal. It's the filters that give the tone its compositional nature, that's the whole fucking point for god's sake.

Believe it or not, emulating analog circuitry is a complete pain in the ass. There are a number of classic arcade games that are currently emulated by simply plumbing the output of the sound chips directly to the user's speakers as if the intervening filter circuitry doesn't exist. It's more straightforward to add support for such circuity than it used to be, but it's not the cakewalk that you loudly and obnoxiously assert it to be.

The reality is that Spy Hunter - or more specifically, the Cheap Squeak Deluxe sound board - uses a quartet of LM359 op-amp chips to perform filtering on the raw DAC output, which is used to generate all (or nearly all) of the sound effects in the game. Sorry to say, but that particular op-amp variant is not emulated by MAME's netlist system. If it were, it would actually be a relative easy hookup, but in this case it isn't. Each individual operational amplifier (and for that matter, transistor and diode) has its own set of characteristics that need to be both A) determined and B) modeled within MAME's netlist system. A whole variety of op-amps have been characterized and emulated, but the LM359 isn't one of them, and it's that which gives Spy Hunter (and other games) the characteristic tone of its sound effects.

I actually started looking into it this evening to see just how much effort it would be to try switching in a near-equivalent part (the LM3900), but if you're going to be such a miserable bastard about it, then honestly, why should I continue to waste my own unpaid time?

You loudly demand that we developers have respect for the games, and we do, it just happens that the games we've been working on don't happen to align with your own desires. Perhaps you should have a modicum of fucking respect for the people from whom you're loudly and angrily demanding the use of their free time.