Sega-Naomi

Hi,



I am a french Arcade player, I have a Sega New Astro city. Since a few months, I use a Nvs4000 power supply for my cabinet and all worked well. Yesterday, I settled on it a Naomi system board and it works. But now, when I put another jamma game, not naomi like Street fighter 2 or Raiden Fighters, the sound is bad with many interferences.



I do not understand...unless I did a mistake in the setting (see attached pictures)! I am afraid to have broken a component into the nvs4000.



If you have any idea to help me, I really thank you.



Benoit.



http://picasaweb.google.fr/Wangfufr/MesImages

Although there is nothing wrong with your pictures, it is difficult to tell if there is a wiring problem. I see the jamma I/O to the side of one of the pictures. Where and what is the audio being connected to?

Hi Benoit, I have the same power supply in my New Astro City, and had almost the exact same thing happen to me two weeks ago. It was the first time I put a naomi in this cab with my new JVS wiring for NVS4000 power supply. I switched the amp's output plug to stereo, and got great sound with the naomi. I then switched back to mono output, and put in a PCB, and got no sound at all. I plugged in the stereo output and can barely hear some distorted sound...is this the problem you have? Did you make sure you switched your mono/stereo plug to the speakers back to mono?



I think something must have broken inside my sound amp board, where it is no longer sending the mono output. So I decided to open the power supply and rewire the mono input (from the PCB) over to the stereo input of the power supply. Now I get sound, but it is amplified from the power supply, so I have to keep the pot on the PCB very low so it doesn't distort. Works ok now.

Benoit, looking at your pictures, it looks like you forgot to switch the speaker output back to the mono connector. This may fix your problem. If you get no sound, then you have the same issue I have. Fingers crossed this will fix it for you.

joshua3dg wrote:Although there is nothing wrong with your pictures, it is difficult to tell if there is a wiring problem. I see the jamma I/O to the side of one of the pictures. Where and what is the audio being connected to?

The audio connections are in the bottom of the power supply on the pictures. There is a white socket called "Sound out" and a yellow one called "Sound in". On the photo, the naomi system is not set but, to make it, the stereo wire has to be connected to the "Sound in".

With this power supply, for any jamma game, the "Sound out" is linked to the audio wire of the jamma wires.



My problem is not directly about the Naomi because it presently works. But now when I put another game (not naomi) the sound does not work well whereas it worked well before the first setting of the Naomi!

So I do not understand, and you?



Thank you, Wangfu_fr.

Dave_K. wrote:Hi Benoit, I have the same power supply in my New Astro City, and had almost the exact same thing happen to me two weeks ago. It was the first time I put a naomi in this cab with my new JVS wiring for NVS4000 power supply. I switched the amp's output plug to stereo, and got great sound with the naomi. I then switched back to mono output, and put in a PCB, and got no sound at all. I plugged in the stereo output and can barely hear some distorted sound...is this the problem you have? Did you make sure you switched your mono/stereo plug to the speakers back to mono?



I think something must have broken inside my sound amp board, where it is no longer sending the mono output. So I decided to open the power supply and rewire the mono input (from the PCB) over to the stereo input of the power supply. Now I get sound, but it is amplified from the power supply, so I have to keep the pot on the PCB very low so it doesn't distort. Works ok now.

Hi, thank you for your answer!



I think we have the same problem. Also, I have the stereo great sound on the naomi and a very low sound with many interferences on the classic game (mono). And when I put back my older power supply, it works great for the mono sound.



More precisely, with a jamma game like Street Fighter 2, I only link the audio jamma wire to the "Sound out" of the NVS-4000. Anything more, is it good or not? Is it "to switch the mono/stereo plug"?



I think also something have broken in the NVS-4000 but it must be a production default ; it is too strange!



About your repairing, do you have some photos or a plan?



Thank you, Benoit.

Here are the connectors for Stereo, Mono, and Speakers. PCB run off mono (no amplification). Naomi runs off Stereo (amplify the stereo input connector on the right of stereo output).

Dave_K. wrote:Here are the connectors for Stereo, Mono, and Speakers. PCB run off mono (no amplification). Naomi runs off Stereo (amplify the stereo input connector on the right of stereo output).

Hi,



thank you for your help but I am not sure to understand the setting...



On the picture, the naomi is not set. To set the sound of the Naomi, I would have to connect the yellow socket (at the right of the "white" stereo socket you noticed) with the input connector where you wrote "Mono" (see picture A). But like it is done on the picture, it is good for a jamma game like Raiden, do you agree?



Else, with the older power supply, I had to link the two parts of the jamma wires (see picture B).



Thank you, Benoit.

I apologize, it was not clear in the picture where that connector went to. Yes picture "B" was the correct speaker connection for Mono PCB. Does this not work?



My updated picture:

Dave_K. wrote:I apologize, it was not clear in the picture where that connector went to. Yes picture "B" was the correct speaker connection for Mono PCB. Does this not work?



My updated picture:

Hi,



your idea is good and I had the same! But it does not work on the nvs-4000. The sound enters with the jamma wires and goes out by the "Sound out". How did you rewire the mono input (from the PCB) over to the stereo input of the power supply? I am interested in it.



I am contacting many arcade dealers around the World about my problem and for the moment I do not obtain many answers! I am quite disappointed. To buy a new Nvs-4000 from Japan! Why not but without any explanation, the same problem could happen.



Thank you, Benoit.