cabinet speakers/amp

[dphirschler]

I need advice on the speakers for my MAME cab.

[SteveJ34]

On first cab, I used 4" shielded speakers from Happs wired to the infamous computer speaker amp board hack with speaker grills also acquired from Happs me thinks.

No seperate bass channel but its fine for arcade and simple juke.

[Veinman]

I haven't really investigated speakers much. It's always been my intent to just hook up a spare set of Monsoon speakers with sub. I see no reason why they wouldn't work out just great, since they are PC speakers after all.

[namedos]

I went with PC speakers from Creative Labs for the following reasons:

1) They are shielded so I don't need to worry about messing with the monitor.

2) They came with a subwoofer which makes all those explosions sound great.

3) The 2.1 system I bought came with a separate volume control which makes it very convenient to modify the volume.

4) It also has a seperate headphone jack on the volume control so I can play late at night and not bother the family.

5) I was able to pick it up at Circuit City with a rebate for $30.  Tough price to beat.

[dema]

If you're going to go with speakers it makes sense to make sure they're shielded. You don't want to do all the work and then realize your picture is distorted.

I'm using the Klipsch Promedia 2.1 and that covers the base. You can definitely get by with a cheaper set of computer speakers that will do you fine.

I cut a hole in the speaker panel for the speakers, and I plan on using the detachable grill for the satellite speakers themselves. Since they are rectangular speakers, I was thinking they'd be a nice way to integrate them without using what looks like a ventilation grille (like the Midway grilles). If I don't like that I'll just get some circular grills and cover them up that way.

[armax]

hey dema, can you post the dimensions of the holes that you made in the speaker panel as well as the spacing of the screw holes?

[ahofle]

I used these monsoon speakers...
http://www.laaudiofile.com/pm14.html

Because they are so thin, they are VERY easy to mount on the top speaker shelf by removing the speaker foot.  And the sound is superb.  The external volume is mounted on my keyboard drawer for easy volume control.  And the sub is so loud, I have to turn down the bass. 
Mmmmmmmm, asteroids with a sub. 

[dema]

hey dema, can you post the dimensions of the holes that you made in the speaker panel as well as the spacing of the screw holes?

I used the ones from the book, the Klipsch promedias. I have the cd rom at my office -- I can post the template tomorrow if you'd like.

[armax]

Sounds good.  thanks Dema!  Hopefully, I can open them full scale to get measurements.

[Veinman]

I used these monsoon speakers...
http://www.laaudiofile.com/pm14.html

Because they are so thin, they are VERY easy to mount on the top speaker shelf by removing the speaker foot.  And the sound is superb.  The external volume is mounted on my keyboard drawer for easy volume control.  And the sub is so loud, I have to turn down the bass. 
Mmmmmmmm, asteroids with a sub. 

On my monsoons it doesn't look like the speaker foot comes off very easily. Also, my wire runs right into the base of the foot. Luckily they aren't that big and I was planning on routing out rectangles just a bit smaller than the speaker faces, and just setting them face down in the holes.

What did you have to do to remove the feet?

[dema]

Here is the Klipsch Promedia 2.1 template, courtesy of Saint and the Project Arcade book. I believe it is sized properly, but I'm not sure.

[Marky_1979]

Has anyone ever tried using speakers and an amp that would normally be used for a car?

[dphirschler]

This is what I was considering actually.  It wouldn't take much of an amp though.  But if the speakers need to be shileded, then that limits the selection of speakers.

How do these bucking magnets work?  Are they supposed to be glued to the existing magnets?  And how do you know what size bucking magnet to use?


Darryl

[armax]

thanks Dema!

[Sinner]

I have a set of Sony X-Plod speakers I wanted to use...is this a bad idea...I'm building a Project arcade style cabinet...will they be too close to the TV I'll be using??
Is there some way I could shield these???

[ahofle]

I used these monsoon speakers...
http://www.laaudiofile.com/pm14.html

Because they are so thin, they are VERY easy to mount on the top speaker shelf by removing the speaker foot.

[elvis]

I used two 6" Pioneer car audio speakers (4 ohm impedance).  These where left over from my girlfriend's car audio upgrade, so where technically free.

I hooked them up to a cheap $AU 50 ($US 40) car AMP, which in turn is powered by a standard PC 12V power supply.

For that price I'd be hard pressed finding PC speakers that gave the same quality audio.  Best of all, car speakers come with grills that are designed to mount into wooden panels, so I didn't have to hack anything up to make it look nice.  Two holes, and slide the suckers in.

[ahofle]

What did you have to do to remove the feet?

Hmm, it's been a while and I can't remember lol..

[Timoe]

I'm gonna use the Creative Inspire T3000 with the that handy volume knob thing on the back of my control panel.

Pioneer 4" 2-Way Car Speakers that are UNSHIELDED

And I'm just gonna shield them myself with some materials bought from here
http://www.lessemf.com/faq-shie.html#speakers

[Veinman]

Are most people just setting the sub in the cabinet, or are you cutting out a hole in the front so that the sub faces out. I was figuring I would elevate it a bit so that people weren't kicking it, but if I shouldn't be exposing it then it's a non-issue.

[Timoe]

I'm planning on leaving an area open on the back of my cabinet a la Ultimate Arcade II.  I figure I'll just vent the thing out that way. 

I am planning on building some sort of support for it inside the cab tho, just to keep things secure.

[Sinner]

Are most people just setting the sub in the cabinet, or are you cutting out a hole in the front so that the sub faces out. I was figuring I would elevate it a bit so that people weren't kicking it, but if I shouldn't be exposing it then it's a non-issue.

I think bass is non-directional, so leaving it inside shouldn't be an issue...I think I read that somewhere here...

[Veinman]

You are correct, bass is non-directional, but I was wondering if it still needed a way to get that sound "out." However, I am also leaving gaps in the back for passive cooling, so maybe I don't need a dedicated "sub window."

[tivogre]

I'm mounting my sub (very similar to the one you show) inside the cabinet on the speaker panel with the other speakers.  I used the Creative Inspire 2900s:



Construction details are on my website:

http://www.ogredog.com/mame_construction_home.htm

[testicle187]

I'm mounting my sub (very similar to the one you show) inside the cabinet on the speaker panel with the other speakers. I used the Creative Inspire 2900s:



Construction details are on my website:

http://www.ogredog.com/mame_construction_home.htm

Wouldn't that rattle your marquee with the sub being placed up top like that?

[dphirschler]

I think the reason you need to vent the bass speaker is not to get the sound out, but to keep the cabinet from rattling.

Anybody know how close one can put unshielded speakers to the monitor before it becomes a problem?  Does it matter what angle the speakers are to the monitor?


Darryl

[Sinner]

You are correct, bass is non-directional, but I was wondering if it still needed a way to get that sound "out." However, I am also leaving gaps in the back for passive cooling, so maybe I don't need a dedicated "sub window."

I don't think you need to get sound out...like in cars, the subs are usually in the trunk in a box, or in behind or under a seat...the speaker isn't exposed...seems like you feel it more than you hear it...

I'd like to know the answer to this...I would like to know if I should remount my sub in my cab...

[dphirschler]

Here's a good buy.  Check out these speakers.  4" shielded Pioneers for 49 cents each!  I will let you know how they perform... when my cabinet is done.

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=269-568&scqty=2


Darryl

[RayB]

Subs are best on the floor. They are non-directional, and not to mention, it's better if they're reverberating the floor...

[Timoe]

Watch out what you connect those partsexpress speakers to dphirschler, they're impedence is rated at 8 ohms and they handle 5 watts each. 

I'm hooking my speakers up to a 4 ohm source pumping something like 10-15 watts per channel.  That is a good deal though  if it conforms to your specifications.

[dphirschler]

Watch out what you connect those partsexpress speakers to dphirschler, they're impedence is rated at 8 ohms and they handle 5 watts each.

[Timoe]

I don't know that much but I DO know that impedence (ohms) is important.  Most speakers nowadays (i think) use 4 ohms, like car speakers or comp0uter speakers.  Guitar amp speakers sometimes are 8 or 16 ohms.  But if the speaker can only handle 5 watts it wont get too loud.  And if your comp speaker amp pumps out more than 10 watts it may mess up your speakers at the higher volumes.

[dphirschler]

OK, I just read some info on partsexpress.

[tivogre]

OK, I just read some info on partsexpress.  Here is what they say aboug ohms.

It should be observed that providing a lower impedance than the amplifier's documentation specifies can lead to damaging levels of current passing through the amplifier. For example, if an amplifier is rated for 8Ω and the speakers are connected to provide 4Ω, twice the current will be passing through the amplifier than it would with 8Ω and be a potential hazard. Accordingly, if an amplifier is rated for 4Ω and is presented an 8Ω load, half of the current will pass through the amp and the overall sound pressure level will be decreased, compared to the rated 4Ω load. This will be safe for the amplifier, but it will not be an optimal usage of the amplifier's power.

Looks like I will be safe connecting 8 ohm speakers to a 4 ohm amp, although not optimal.  I understand that if I connect two 4 ohm speakers in parallel (per channel) it will reduce the load to 4 ohms.  I wonder if connecting a 4 ohm resister in parallel will accomplish the same thing.


Darryl

I thiunk you meant 2 8 ohm speakers in parallel will give you a 4 ohm load.

2 4 ohm speakers in parallel will give you a 2 ohm load... and almost certainly fry your amp.

2 4 ohm speakers in SERIES, however, will give you an 8 ohm load.

As for the resistor question... It can be done BUT there are some reasons it SHOULDN'T:

     1.  Speakers aren't really purely resistive.  They actually have an IMPEDENCE, not  a resistance.  using a resistor may much with the frequency response of the driver.

     2.  The resistor will use up half of the power of your amp to that channel and dissipate that power as HEAT, rather than sound.

If you want to use the cheapy speakers, wire 2 per channel in series to give an 8 ohm load.  That way, each speaker per side will only "see" half of the amp's power output per channel.

[dphirschler]

OK, I did make a mistake in my above post.  I corrected it.  As for the 4 ohm/8 ohm question, I think I am just gonna get an amp that can handle my 8 ohm speakers.  I have two or three in mind now.  That T-amp is looking good right now.


Darryl

[dphirschler]

Here's a nice amp for cheap.  Shipping was kind of steep though.

http://mach5products.com/merchant2/merchant.mvc?Screen=PROD&Product_Code=Amp1&Category_Code=CP

PC audio amplifier  -  Price: $34.95

This audio amplifier has 3 20 watt amplifiers,(left,right,subwoofer). It has a mini 1/8" input so it can be plugged into the output of your computer or any other line level source. It comes with 3 connecters that are 1/4" phono so you can plug them into your speaker.It uses a power supply power plug to power the unit,(just like a hard drive). Note: you do not have to use the subwoofer output for the unit to work properly.

Darryl