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Capcom Q-Sound amp help?

l_oliveira said:
SmokeMonster:

The problem with that is that there are several methods of storing QSOUND encoded data. The method used on CDs or previously recorded media can processed before recording and then any standard stereo sound amplifier can be used.

Qsound can also be encoded also in a way it requires additional circuitry to "activate" so Qsound could bite in some dough from royalties at the hardware (the amplifier chip).

Similar to how Dolby Laboratories were making their money of Compact Cassette players back in the 70s and 80s by adding it's tape enhancement/noise suppression technology on take deck chips. That particularly on early 80s was very common.

Archer/QSOUND inc tried to emulate the Dolby laboratories business model but, well, we know that flopped. lol
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can I help fund research for this? My big blues need to sing the bloody cries of the losing opponent.
 
These Q-Sound amps are a thing of beauty. Capcom spared no expense with the all-Elna cap outfitting, including ten Duorex II ARE series.

On my standard 18V Q-Sound PCB:

The two ICs attached to the heat sink are NEC uPC2500H 45-watt powered audio amps (Datasheet).

The three ICs near the RCA input are NEC c4570HA op-amps (Datasheet).

The rectifier near the power input is a SHINDENGEN D3SBA20 (Datasheet).

This PCB doesn't seem to have any processing power unless I'm missing something.
 
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Thanks for confirming that. I thought that the first SIP chip would be a QSOUND processor. (analog, not digital)

So if it's indeed just an amp (but a high quality one) then it doesn't really need to be the Capcom one on your cab.
 
Does the Q-Sound PCB not power-on unless speakers are connected? I'm waiting on a speaker terminal to arrive before I can connect speakers to test it, but so far it isn't powering on when connecting it to my CPS-2's RCA. I've tried both 18V and 12V and the Q-Sound PCB's power LED won't light up.

20160717_142555.jpg
 
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I think the board requires AC voltage (12VAC, not 120VAC lol), not DC.

That, because from a AC input it's possible to generate +12V and -12V. And that board sure do look like something that would use symmetric power.
 
l_oliveira said:
I think the board requires AC voltage (12VAC, not 120VAC lol), not DC.

That, because from a AC input it's possible to generate +12V and -12V. And that board sure do look like something that would use symmetric power.
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Ahhhh! Thanks! Now I need to find some creative use for this 18V DC PSU... :D
 
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If your board is the 18V version it will be 18VAC instead, FYI.

That power supply looks like 18VDC not VAC. :)

Edit: Are you trying to avoid the original transformer? Why not just use it?
 
I didn't get the original transformer with it, so I had to improvise. I just won a 4A 18V AC transformer for $10, so I should have it running again soon. I'm turning the Q-Sound PCB into a stand-alone audio amp for my PVM/supergun setup.
 
Make sure to share with us your results. ;)

Actually, that kind of setup is common on retail amplifiers (stuff from SONY or other companies) where a heavy AC transformer is used to obtain voltages as high as 60V (+30/-30) for a symmetric bridge style amplifier.
 
One more little question. The AC PSU I ordered has an earth line, but should I even connect that to anything since I don't plan on having a metal chassis?
 
Just powered it on successfully. If anyone else goes down this path, a 4A transformer might be a tad overkill ;)

Thanks again for the help, Leo! I've added a headphone jack, since the speaker output pins are wired +--+ just like all 4-pin standard 3.5mm audio jacks (do not connect headphones here though!). I'm going to make a 3.5mm-to-speaker terminal cable when the parts come in. I'd rather have the correct JST female connector, but I couldn't find it--same thing for the power input. I'm also going use a plain RCA gain control for volume.





 
I'd say it's a horrible idea use a headphones jack on such a powerful amplifier.

Lest you ruin your eardrums with it.
 
My plan is to make a 3.5mm to speaker terminal cable that will plug in to them, not for headphones. I thought it looked rugged enough to handle the wattage--is that still a bad idea? If so, I'll just wire the terminal directly to the board for now. Eventually I want to get the correct JST connector to plug in on top (and remove the 3.5mm jack) but so far I haven't found one.

Also, sorry for thread-jacking this. One question has spiraled into many.
 
The danger is connecting a headphones set to such a powerful amplifier. It has plenty of potential to explode eardrums on headphones... lol
 
SmokeMonster said:
My plan is to make a 3.5mm to speaker terminal cable that will plug in to them, not for headphones. I thought it looked rugged enough to handle the wattage--is that still a bad idea? If so, I'll just wire the terminal directly to the board for now. Eventually I want to get the correct JST connector to plug in on top (and remove the 3.5mm jack) but so far I haven't found one.

Also, sorry for thread-jacking this. One question has spiraled into many.
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Wow, all of your information has only helped! So thanks to you, and L_oliveira!

I received two Q-Sound amps just a couple days ago and also ran into the VAC/VDC conundrum. Ordered the same model transformer as you and should be in business in another few days since it's shipping from in-state :D.
 
I hope you have better luck than I did. I got mine to power on, but never could get any sound out of it. As far as I can tell, everything is perfect, so maybe I just got a bad PCB. I did end up hard-wiring a speaker terminal to mine as leo suggested, but it's all back in a box now for me to mess with in a few years.
 
SmokeMonster said:
I hope you have better luck than I did. I got mine to power on, but never could get any sound out of it. As far as I can tell, everything is perfect, so maybe I just got a bad PCB. I did end up hard-wiring a speaker terminal to mine as leo suggested, but it's all back in a box now for me to mess with in a few years.
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I'm at the same point. It's hooked up, no sound.

Did you check your transformer? I was reading a forum post on how one guy's would work because it was receiving 19.4V instead of 18, and that the Q-Sound amp shuts down when overfed. Tested my transformer and it's outputting 20V on the nose T_T.
 
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Mine was at about 19V too. I did try hooking the PSU to a Variac and testing it at 18V, 17V, and 16V with no luck.
 
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