HELP: Most overlooked part.. SOUND!

[JoeB]

My setup:

Arcade machine with WG7000 series monitor converted to MAME with J-PAC, ArcadeVGA, Windows XP, SBLive and other goodies..

My problem is that I have a pair of 6 1/2" Alpine car speakers, a sony amp, and a 15AMP 12V power supply.

I hooked it up, and the speakers do some funky stuff to the monitor! Further more, the inside of the machine get HOT.. I mean REALLY HOT thanx to the power supply, and even more so.. AMP!

So.. Should I spent more $$$, try to shield the speakers or should I call it a day, get computer speakers and try to mount them inside??

The car speakers sound GREAT! But they're currently on the floor outside the cab!

Let me know what you think...

Thanks in advance.

[BombProofPlane]

someone already answered this try a search

[REBIRTH]

I would go computer speakers.  I have a 5.1 computer system + 2 extra speakers and it sounds incredible.  The arcade is in the basement and on about 33% volume the thing is loud enough to hear the arcade sounds on the top floor of my house.  No worry about magnetic fields screwing with your monitor, and no heat.  

[Mike]

I would definately go with computer speakers. A set of these http://www.compusa.com/products/product_info.asp?product_code=303917&pfp=BROWSE will work great and be plenty loud enough.

[GSXRMovistar]

I'd also recommend the creative speakers. I've got a set of 5.1 (5300) hooked up to my pc and the sound is great for games.

They are also very cheap I got the 5300 set for

[Cisco Kid]

I used a pair of 4" Sony Xplod speakers myself  

you can use the Alpine car speakers ... just epoxy a cancellation (ferrite) magnet onto the back of the speakers.  The two magnets should repel each other when attaching ... hence the reason you need epoxy.

The cancellation (ferrite) magnet should only be 1/2 to 2/3 the weight of the main magnet. (don't exceed 2/3 ... or this will create a new magnetic field ... not good)

You can get the magnets here (if you can't find them locally) : http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=3&ObjectGroup_ID=571&SO=2

after the epoxy has dried ... you'll notice that you'll be able to get them within a few inches of a computer monitor without them effecting it ... and the speakers will be pointing away from the monitor anyway ... so you'll be golden  

... as for the overheating problem ... I'm not exactly sure why.  You haven't given enough info for me to help you troubleshoot the problem.

... list the exactly speaker model, RMS watts, etc.

... also list your AMP model and power ratings

... list the ratings for the 12V power supply (model would be nice) ... is the 12V @ 15A an rms value?

I'm guessing your AMP is to big for your 12V power supply and its getting straved on amps ... hence the heat problem. (since your not running it at 14.4V ... the amps drawn is going to be more)

for example my little Sony 4" speakers are in the 45 Watt RMS range and thats about all my 200W MTX amp can handle ... plus that draws 15-16A on average ... and has a 20A fuse plus I'm powering it with a 25A adjustable power supply ( mines at 13.2V).  It stays fairly cool.

[night]

i used an aiwa shelf stereo.
to be revealed soon . im in the middle of moving to a house, and will get lots of pics as i put it back together.

[AlanS17]

I recommend Logitech speakers. Many models have their own mounting brackets and wired remote controls. I love mine.

You don't need 4.1, 5.1, or any other surround system. A pair of stereo speakers with a seperate sub will work perfectly. Arcade audio doesn't support more than mono sound most of the time, anyways.

[JoeB]

Here's the specs on my system:

The speakers are Alpine 6 1/2" SPS-170A speakers.  The specs on them can be found here:

http://www.crutchfield.com/cgi-bin/S-2ThxCo8RKX6/ProdView.asp?s=0&c=10&g=52000&I=500SPS170A&o=m&a=0&cc=01&avf=N

The AMP is an old Sony 2 Channel AMP.  It pumps about 20W RMS per channel.  It's fuse rating is about 15A.

The power supply I use is a Pyramid one.  It's rated about 12A avg (so it can max higher, but not for long).  So as far as I can see, the amp and power supply are evenly matched.. the problem is the amp gets pretty hot.. not the power supply.

My bigger problem is the actual speakers.. the magnets on it is HUGE!  Heck, the speakers are HUGE.. the tweater stickets out the front..

So before I go hacking the cab, I want to see if it's worth going this route.. or just get a pair of computer speakers..

Mind you, most computer speakers have a seperate sub.. but I don't want this sub.. I want the speakers to have good base on their own!

[Chris]

If you're not also making your cab a jukebox, there's little point to cranking up the audio of an arcade game that loud.  Even the cruddiest amplified PC speakers should be more than a match for the emulated sound systems of old arcade games; a set of decent PC speakers should blow the coin door off the machine.

If you do go the car audio route, remember that your whole machine will now be vibrating, so you'll have to batten everything down....

--Chris

[dac]

hmm, I use both computer speakers (at the top) and the TV audio... I rarely see people post that they use the built in TV speakers, so thought I'd offer that tip...
It's somewhat helpful to use them, as the TV remote can also control the sound levels... so the computer speakers give a "base" level of sound (not that loud) but when you need to pump it up, the TV speakers can fill the room...

[Cisco Kid]

JoeB ... if you use the cancellation magnets ... the interference caused by the magnets will go away.

Computer , TV, and Home audio speakers use the same technique ... the only difference is that they come with a MuMetal  shielding can too.

As for why your amp is getting hot .. I'm no car audio expert ... but your amp doesn't even come close the handling the recommended power range of those speakers which is 2 - 40W RMS.  I wouldn't be suprised to see your amp totally fry if you keep at it.  Most sites recommend at minimum a 200W amp for those speakers.

[JoeB]

Cisco Kid:

The AMP is a Sony XM-3021.  It's rating is:


"30 watts per channel minimum continuous average power into 4 ohms, both channels driven from 20-20,000hz with no more than 0.04% total harmonic distortion per car stereo ad hoc committee standards"

Speaker Impedance: 2-8 ohm
- Max power output: 60W per channel minimum RMS at 4ohm
- Rated output: 30W per cannel (20hz - 20khZ, 0.04% THD) at 4 ohm
- Freq response: 8hz - 100kHz
- Harmonic distortion: 0.005%
- Current drain: 8A (at rated output)


From the above, I assume the amp can push 30W RMS per channel.. which is more than powerful enough for these 40W RMS speakers..  correct??

I called Alpine.. the speaker magnet weight is 10oz.  As such, I'll be ordering the 6oz magnet for distortion reduction.

My question(s) to you are:

- Assuming the distortion is removed, and the amp is mounted outside the cab (on the top, where it's not visible, and at the same time it's open the room for cooling), how do you think the system will sound?  Notice that I do not have a sub.. I assume 2 6 1/2" Alpine's are better than any computer speaker / sub combo.

My other alternative is to go with the Altec Lansing 621 computer speaker system.

This system is made up of 2 satellites (3" full range driver + 1" tweater) running 100W RMS including the sub put it has a wired remote..

ARGGGG... This is driving me nuts!

[Cisco Kid]

they should sounded great ... heck were talking Alpine speakers ... the freq range on those speakers kick --I'm attempting to get by the auto-censor and should be beaten after I re-read the rules-- ... you should be in MAME heaven with excellent sound.

there going to look good to mounted above the monitor ... should be a sweet setup. (post some pics)

the 6oz. ferrite magnet will definitely do the trick ... say goodbye to monitor interference  

Like I said I'm no car audio expert ... I would think 30W RMS would get the job done without the amp getting terribly hot.  I know from reading reviews and recommendations about those speakers ... most sites used a 250W amplifier that had 50W RMS per channel.

I'm guessing that the 30W rms value is the 14.4V rating ... which means the actual wattage at 12V would be a good deal less. (can't find anything on that amp ... must be a really old model or something)

[said7]

I second what Alan said I did a side by side comparision with the jbl's, Altec Lansing, and Creative.

The logitechs sounded the best. I got a 5.1 system for only 70 bucks. Its well worth it.

[JoeB]

You're right.. it is an old AMP.. but for ~30$US.. you can't go wrong..

The AMP was made by Sony back in 1993.. (I find older amps to be of higher construction quality than new ones, so since it works, I'm sure it'll work for a long time).

Here's more info I got from the manual (which I found online):

- It has build in thermal protection.  If it gets too hot, it shuts down.
- It requires a 15A fuse
- I think these values are for 12VDC since that's all it says all over the manual.

I know I shouldn't punch the amp too hard (I've been an audiophile in my car for 5 years now) so I raise the volume on my SBLive, and lower the sensitivity on the amp. (This results in higher voltage going through the line to the amp and results in less noise added to the line, since the amp shouldn't work as hard with lower sensitivity).

OH well..

I'll test out the amp today sitting on the table.. could be just a problem with no circulating air in the cab.

[grafixmonkey]

I know if my shelftop stereo amp sat in my cab with no air flow, it'd melt down pretty quick.  Get some 92mm, low rpm Panaflo fans, and put them somewhere in the walls of the cab where they won't be noticed.  They're extremely quiet - I can barely hear mine if I put it up next to my face.  Put some blowing in and some exhausting out if your cab doesn't have any ventilation holes, to avoid the fans pushing air against a pressure difference (makes them louder.)   Two or four of those should make plenty of ventilation.