Supergun PSU and audio questions

[randombs]

just curious about something - seeing as a lot of supergun guides utilise an at/atx psu, how many watts are needed for something like, say, street fighter 2 champ ed? what about a cps2 game like super sf2 (what with the fan and stuff). i'm not planning on using atomiswave, naomi, etc, just maybe a few streetfighters

reason i ask is i'm interested in building one soon, and would like to use an xbox psu in it as a) it's small, b) it's silent and c) it appears to provide the voltages needed (+5v,+12v) although i'm not sure about -5v (had the pinouts before, but can't find any on the net anymore). the xbox psu can handle 145W

i've also got a 110W silent mini atx psu too that i could use

also, what's the deal with using a proper arcade psu? is it only really necessary for really old games?


about the audio, i know the games have amplified sound, but if i turned the volume right down, would it be safe to use on the tv? how would i know how loud it should be?

thanks for any help given

[Treble]

I'll try and help a bit:

1) -5v is normally used to light the lamps in the cab, so you won't need it.
2) I'm not sure about those lower wattages, as I have no figures for what the boards actually use. A regular 300w is fine, and you can get ones that are silent - this I do know =]
3) Don't bother with your TV's speakers. Run the sound either through your stereo or a pair of TV speakers. A lot of boards don't have adjustable volume (if they have, it's normally a pot[entiometer] on the board). It's not the volume that causes a problem, it's the voltage. IIRC, a TV's speakers (accessed through the red and white RCA jacks) only take +5v, and the JAMMA rig outputs +12v. I'd have to check, but I think this is the reason.

[randombs]

thanks for that info. yeah looking at the jamma pinout there's no reference to -5v anyway

well, i found the pinout for the xbox psu, and it has the required stuff (+5v, +12v)

i guess a potentiometer could be used as a volume control if i needed it, but yeah i'll probably steer clear from sending the audio to the tv anyway.

[guiddruid]

'standard' arcade psus are about 110Watts.

I would recommend using a real arcade psu as they have an adjustable +5V output. Some arcade boards can be _very_ picky about exactly what voltage they will work with.

The audio out from most arcade boards is designed to drive a (pair of) speaker(s) directly. The audio input of a TV feeds into an amplifier that drives the TV's speakers. PCBs may also want to drive both connections of a speaker (not have one end connected to ground), a TV needs a single-ended signal. Circuits can be made to adapt the PCB output to feed into a TV, but you would need to know what you are doing...

FWIW; if you have the room then just buy an old Jamma cab, there's nothing like it, and they are not that expensive.

hth,
gd

[randombs]

if i had the room i'd have a jamma cab by now

besides, the reason i was considering building one is because it'll cost next-to-nothing (i have the psu already, etc)

[raiden]

Some older PCBs use -5V for sound, as well. But Streetfighter games aren?t that old, CPS2 doesn?t need -5V.
Watt aren?t much of a problem, either, if you?re playing newer games. 110W should easily suffice.
Putting regular Jamma audio through PC speakers can damage some PCBs. However, if you?re playing CPS2, it has stereo output designed to be connected to an amplifier, so no problem there. You need to turn QSound on in the options to hear it, though.

[randombs]

thanks raiden i was thinking about the rca sockets too, figured they'd be plugged into regular speakers. i wasn't planning on using pc speakers though - got an old hifi one (8 ohm impedance i think)

i guess what i'll do is source a random crap jamma board (obviously nothing too old!) with dodgy sound or something just to build the supergun around to see how i fare before diving in and getting a decent (and thus, fully working) game like sf