Messed Up Modulated Sounds on Balloon Fight and Clu-Clu Land

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RJP1138
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Joined: Sun Dec 09, 2018 8:49 am

Messed Up Modulated Sounds on Balloon Fight and Clu-Clu Land

Post by RJP1138 »

All of the following is observed on real hardware, not emulators.

If you compare the NES version of Balloon Fight to the VS arcade version and pay attention to the bird flapping sounds, the VS sounds are better, and I think it's because on the VS version their frequency is successfully modulated up and down to give that satisfying chirp effect.

Another quirk with modulation is in Clu-Clu Land. The ebullient percussive sweeps that are supposed to play at the end of a round of Clu-Clu Land sound sound like scratchy plunks on an 8 Bit marimba, unless by luck the player is sending out a sonar wave simultaneously with the ending of the round. However this happens on both home and arcade versions so this one might have nothing to do with it being on a different system.

According to raphnet, aside from the existence/non-existence of lock-out chip, dip switches, and coin switch, the main functional differences between VS Unisystem and NES relate to graphics: 2KB more for the PPU with different color palette. Of course also the memory map given that one uses cartridges and the other ROM chips. But there is no mention of sound hardware differences.

I am not a game hardware expert, so apologies ahead of time if the following questions may come across as absurd and ignorant.

If the VS and the NES have the same sound hardware, couldn't that mean that the sound code in Balloon Fight NES and VS Balloon Fight are identical?
If so, why doesn't the home version chirp?

Could the cause of no chirping be the same as what prevents the sweeps in Clu-Clu Land?

Can NES Balloon Fight be patched to chirp?

Can Clu-Clu Land be patched to always sweep?
lidnariq
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Joined: Sun Apr 13, 2008 11:12 am

Re: Messed Up Modulated Sounds on Balloon Fight and Clu-Clu

Post by lidnariq »

As it turns out, they don't have the same sound hardware.

The Vs. System has a 2A03(letterless). The home console has a 2A03G (most likely. Could be a 2A03E or 2A03H).

The only difference that we've discovered so far, because it's so huge, is that the newer version supports tonal noise mode; the original doesn't at all. This difference is easily heard as the last note in the death jingle on Balloon Fight.
RJP1138
Posts: 2
Joined: Sun Dec 09, 2018 8:49 am

Re: Messed Up Modulated Sounds on Balloon Fight and Clu-Clu

Post by RJP1138 »

So that is why the last note of the closing song buzzes on the NES version. Okay. Cool to know.

Thank you lidnariq for your response.

I don't think that difference explains the lack of modulation, but if my endgame is to play a chirpy NES version of Balloon Fight, there is always MAME. The birds chirp there.

Still does not address the quirky behavior in Clu-Clu Land though. I suppose "correcting" that is hopeless without source code, right?
Great Hierophant
Posts: 780
Joined: Tue Nov 23, 2004 9:35 pm

Re: Messed Up Modulated Sounds on Balloon Fight and Clu-Clu

Post by Great Hierophant »

I remember reading something online that stated that Vs. Balloon Fight and home console Balloon Fight were not developed by exactly the same team. Satoru Iwata did the programming for the home version, and if I remember rightly, the programmers for the Vs. Balloon Fight version had to come to him for help with their physics engine. Iwata was a 6502 Guru in those days (he owned a Commodore PET) when most Japanese programmers only really knew Z80.

Early Famicoms can also come with the revisionless 2A03 CPU : http://jpx72web.blogspot.com/2016/11/fa ... d-new.html
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