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I actually removed the PSU and cleaned the connectors during the speaker fix. When I use the RCA connectors I get full stereo, but when I switch to JAMMA connector sound it's mono left. Where does the Blast City split mono audio to left and right? Does it happen on the JAMMA loom or in the PSU?
And to be clear you are switching the connector on the 001 loom? There's a physical connector switch to go from stereo (RCA) to mono (JAMMA). But yes it should be dual mono, not playing out of one side.
 
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I’m a bit late on this, but is there any guide to hacking the jamma harness on a blast to switch between stereo and mono?

Basically creating a 001 loom?
 
I’m a bit late on this, but is there any guide to hacking the jamma harness on a blast to switch between stereo and mono?

Basically creating a 001 loom?
https://wiki.arcadeotaku.com/w/Sega_Blast_City_Wiring_Guide#Cabinet_I.2FO_board

Line level input is on CN5.

If you connect both jamma audio and line level at the same time you will blow a resistor on the amp, so make sure you only have one connected at a time.

Sega Model 3 (Blast, NVS4000, etc) no JAMMA sound / buzzing fix
 
Thanks. I think the route to go is to get two 6 pin connectors, one with two jamma mono wires and the other with the four stereo pins.

This way it would be impossible to have both connected at once, since they take the place of each other, and I’m guessing is how the 001 loom functions.

Thanks for the help. I’ll have to find the pin sizes for the CN5 harness.
 
This way it would be impossible to have both connected at once, since they take the place of each other, and I’m guessing is how the 001 loom functions.
That's how it is on the original loom.

I’ll have to find the pin sizes for the CN5 harness.
Connector series is JST RA. It's standard 2.54mm pitch. You can use Dupont connectors if you wanted.

http://www.jst-mfg.com/product/detail_e.php?series=206
This is extremely helpful. Thanks!
 
Looking to restore my Blast City speakers, but at the same time improve quality and add a little bass to the mix. I'm not going to be using the original setup though, I have a JPAC connected to MAME PC and it works great, so I'll be leaving that in there for a long time. Wiring will go directly from the motherboard output to an external amplifier.

The plan right now is to get 4 of the above mentioned Aura NS2x3 speakers (wired in series to 8ohms), a Leipai 2.1 amp , and a 6.5" woofer built into a very small box to sit just outside of the cabinet behind it.

Can anyone think of a better way to accomplish what I want, which is just basically clean and slightly improved sound while keeping everything as original appearing as possible?

Thanks!
 
Has anyone tried mounting Harman Kardon SoundSticks in their Blast City?

The satellites are 2" X 10" which seems like it would fit in the Blasts speaker compartments.

Product Website
 
Another satisfied customer with the Auras. You definitely need to cram them in, and I worry about the bent plastic's long term integrity, but given the options I think this was the best route. I could not enjoy the audio at all with my speakers' original condition, but once installed everything sounds really good.

Just a note, they are a very tight fit after you've installed the Auras. Make sure you trim down any sealant (hot clue, caulk) if you run into fitment issues.

Original condition:
IMG_20200808_015035 copy.jpg
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One rebuilt module:
IMG_20200907_181620.jpg
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So how come these dudes with laser cutters making plexiglass sandwich cases for PCBs haven't made replacement blast speaker boxes for use with aftermarket drivers yet?
I have it basically done, with options for different drivers, etc.. but, dont have a blast to fine tune it further, so put it aside for the time being. Also, dont real;ly have anyone near me that wants to deal with swapping out the speakers a few times to test so.... Also, space it at a premium in these boxes. my design extends the oem box, and I make 2 compartments, one that handles low end/bass, rear firing/ported, and the other with front firing mid/high drivers. Also, the drivers need to be magnetically shielded. Anywho, maybe Ill revisit it again at some point.
 
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I have it basically done, with options for different drivers, etc.. but, dont have a blast to fine tune it further, so put it aside for the time being. Also, dont real;ly have anyone near me that wants to deal with swapping out the speakers a few times to test so.... Also, space it at a premium in these boxes. my design extends the oem box, and I make 2 compartments, one that handles low end/bass, rear firing/ported, and the other with front firing mid/high drivers. Also, the drivers need to be magnetically shielded. Anywho, maybe Ill revisit it again at some point.
So... not nearby, but let me know if you need someone to test things. I have a Blast that I need to swap the speakers out, and I was going to go with the Auras path, but can hold off if we want to give it a go. Let me know.
 
I have it basically done, with options for different drivers, etc.. but, dont have a blast to fine tune it further, so put it aside for the time being. Also, dont real;ly have anyone near me that wants to deal with swapping out the speakers a few times to test so.... Also, space it at a premium in these boxes. my design extends the oem box, and I make 2 compartments, one that handles low end/bass, rear firing/ported, and the other with front firing mid/high drivers. Also, the drivers need to be magnetically shielded. Anywho, maybe Ill revisit it again at some point.
So... not nearby, but let me know if you need someone to test things. I have a Blast that I need to swap the speakers out, and I was going to go with the Auras path, but can hold off if we want to give it a go. Let me know.
Maybe we can do something, just got in a fresh batch of acrylic :) stuff is like gold now, got lucky I was able to place an order for the amount I needed.
 
I have a blast city i'm willing to change speakers around with. It's annoying that you have to remove the monitor in order to easily change the speakers.
 
I’m going to have to pull the monitor in my blast anyway, so happy to be a test bed if you need one.

Will give me a good reason to have Bagheera over!
 
Maybe we can do something, just got in a fresh batch of acrylic stuff is like gold now, got lucky I was able to place an order for the amount I needed.
Sounds good, just let me know @Derick2k. And it looks like @KaPH33n and I are both in SF, so we could double up or do one package to Cali.
 
Add a sub. I need more bass! These speakers have no body. I regret not cutting those tweeters out when I was in there installing the Aura's.
 
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