Plugging a soundcard line-out directly into a JPAC

[Diewrecked]

Hi all

I have seen the threads about this saying that you need a sound card with an amp on it in order to plug the speakers of a JAMMA cab directly into the line-out of the sound card (and, in my case, the SPKR + and - terminals of a JPAC) without needing to go through a pre-amp.

My question is: what sound cards will deliver enough output to power the speakers directly without having to power them somehow? This would be by far the easiest and most elegant solution I think ... unless of course you know of any others...?

Many thanks in advance guys
Jon

(edited to change the subject line)

[Diewrecked]

PS my mobo is an Asus K8V-VM mobo with a Realtek ALC660 chipset onboard, would that deliver enough power or would I need a separate sound card?

Thanks again all

[SirPeale]

I doubt it.  Just get a set of cheapie powered speakers.  You have the option of either wiring the output right into the J-PAC or putting those speakers into the cab.

[Diewrecked]

Thanks Peale.

Is there no sound card that will deliver enough power to drive the cab speakers directly then? I would like to keep them if I can.

Thanks again
Jon

[CheffoJeffo]

I haven't seen an amplified sound card in a long time, but then I haven't looked in an equally long time.

When I put a PC-based rig into a JAMMA cabinet, I put an amplifier in-line between the sound card and my JPac.

Every now and again, the local electronics shop clears out little DIY electronics kits and I picked up a number of amplifier kits. They run off of 12V, which I grab from the PC power supply.

Here is a pic of the kit installed in a rig that I am about to (well, intend to is more accurate) recycle into a new project.

[ArtMAME]

I did a JAMMA-based MAME cab for a friend.  I ended up just putting an extra set of powered PC speakers in there along side the original speakers.  So his MAME setup uses the powered PC speakers, and if he wants to test or use JAMMA boards, he can just disconnect the harness from the JPAC and connect his JAMMA board which will use the original cab speakers.

[TPB]

When I put a PC-based rig into a JAMMA cabinet, I put an amplifier in-line between the sound card and my JPac.

CheffoJeffo,

And your JPac is then connected to the Cabinet speakers (as opposed to PC speakers) ?

[Diewrecked]

I picked up a number of amplifier kits. They run off of 12V, which I grab from the PC power supply.

Here is a pic of the kit installed in a rig that I am about to (well, intend to is more accurate) recycle into a new project.

CheffoJeffo this looks like it's exactly what I need. Would you be willing to sell one to me? If so, whereabouts are you based please? (I'm in London)

Many thanks mate

[Zebidee]

You do need an amplifier.  Cheap PC speakers should do the trick.

I do suggest that you change the original cab speakers though.  In my experience (and I have seen a lot of cabs), the original speakers are pretty crappy and
NOT MAGNETICALLY SHIELDED!!.

This means that they may damage the monitor over time, especially if positioned close to the monitor.  I think that the original manufacturers didn't really care about this, as they are only concerned about $$ in their pockets and the next year or so of operation.  On the other hand, most PC speakers ARE magnetically shielded, as they often are placed on either side of a PC monitor.

This means REPLACE THOSE DODGY ORIGINAL SPEAKERS.

Look here to find out how to wire a volume pot in while you are at it:

Volume Control Mounting and Wiring

[CheffoJeffo]

And your JPac is then connected to the Cabinet speakers (as opposed to PC speakers) ?

Yep.

EDIT: I should say that one big reason why I do this is so that I can yank out the PC rig and drop in a JAMMA board at will. Mostly this is so that I can retask a cabinet, either to keep (I did this recently on my vertical MAME cab ... yanked the PC, which you saw in the picture and will be reused, and dropped in a 48-in-1) or to sell (it's easier to sell a JAMMA cab than a MAME cab). If you have no desire to do either of those things, then the solution is perhaps less compelling.

[CheffoJeffo]

CheffoJeffo this looks like it's exactly what I need. Would you be willing to sell one to me? If so, whereabouts are you based please? (I'm in London)

Unfortunately, I have only one kit left from the batch that I bought and it is already tasked to a project. Sorry.

[Diewrecked]

Unfortunately, I have only one kit left from the batch that I bought and it is already tasked to a project. Sorry.

Not to worry. Looking at Zebidee's post above (thanks Zebidee ) I'll be better off with noddy PC speakers anyway.

Thanks all

[KDOG]

Here is a link to some
Amp ktis

[TPB]

This new Arcade Lightgun interface, also includes a built in Stereo Amplifier.

Perhaps overkill (if you're just after the amplifier), but worth considering ...


http://www.nanotechent.com/opti-gun.php

http://forum.arcadecontrols.com/index.php?topic=82460.0

http://forum.arcadecontrols.com/index.php?topic=81154.0

[G1zm0]

since your in uk try this link for maplin http://www.maplin.co.uk/Search.aspx?criteria=audio%20amplifiers&source=15&SD=Y

it will give list of all there audio amps, pre built and salf assembly,

think i will pick a few up my self

[Diewrecked]

TPB - many thanks but yeah that really is overkill for what I'm after!

G1zm0 - that looks ideal except I really CAN NOT solder for toffee!! Is there one available that you know of that I can just plug in in-line, ie, with stereo minijack sockets to plug into my soundcard and speakers and a little molex (or whatever) to plug into the PSU? Sorry but I really am cr@p at electronics. Otherwise it looks like I'm going down the "bin them and replace with noddy PC speakers" route.

Thanks again everyone.

[SirPeale]

Find a dead circuit board and start practicing. 

[Blanka]

These blocks must be suitable for complete NOOB's on soldering:

Noob mudule
This is the documentation
You can feed the modules with the 12V from the PC power supply. 1amp is enough for the 12W module, 500mAmp for the 3.5 watt version. Do not connect a AC transformer directly.
They are also available in 12 and 18 watt
You put m between the PC and the jamma-plug.

[Diewrecked]

Hi guys

So quick update - maybe I'm just lucky but my Goliath Mk 3 cab has speakers that work with the line-out of my soundcard connected directly into my JPAC.  Don't need any kind of amp, they just work!! Well chuffed 

My trouble now is that I'm only getting sound out of the left speaker. I have them wired to the JPAC with a stereo minijack plugged into the line-out of my soundcard, with the other end cut and stripped, such that the live from left and right (ie the red and white shielded cables) are twisted together and connected to the SPK+ terminal on the JPAC, and the ground (black shielded cable) is connected to the SPK- terminal. Is this correct? I did try with the black cable connected to the GND terminal but then I got no output whatsoever.

Anyone shed any light please?

Many thanks in advance yet again you guys

[TPB]

I'm only getting sound out of the left speaker.

From the J-PAC FAQ's :

The JAMMA standard is for only one speaker, mono sound.

http://www.ultimarc.com/jpac1.html

[Diewrecked]

Thanks TPB. Yes the cab is based on the Electrocoin standard which is stereo and has two speakers, but has a converter loom going to JAMMA (which the JPAC is connected to) - I just need to take the two speaker feeds from the original Electrocoin harness before it goes to the JAMMA loom and connect them directly.

Cheers fella