Amplifier Makes No Difference in Quality

Hello guys. I had my dad hook up my new NVX VAD 10004 amplifier to my stereo and my 30 amp low ripple dc switching power supply and i kid you not the difference in quality is zero. It has literally no difference in the quality of the sound from deck power (22 watts x 4) from a kenwood kdc-x303 head unit with mm692 polk audio speakers. Yes it has no difference in quality from having just receiver power to 150 watt power handling speakers as you can imagine that's pretty flat. So... What gives? My dad concluded that it's the deck that's not producing a signal of some sort to the amp cause when he hooks the amp up without bypassing it on the channels for the speakers it lights up and gets warm as if it's working so I don't think it would be the amp although it could be. The one thing I did notice about the amp is it did make the music a little bit louder perhaps by about 3-4 notches out of 35 that the deck can go up to. Another thing that's odd is we hooked up everything on the rear channels and when we went to hit the fader for rear it went silent the more we went to the rear ... Then we hit front and it was the same as on zero (15-0-15). And now that he hooked it all back up the left speaker just isn't working anymore I can hear the white noise with it (which shouldn't be the case since the preamps are 5volts) but it produces no sound. What's the verdict guys? Cause I'm not really experienced with these things I think I'm going to get a new head unit the Pioneer DEH-80PRS and I'm just praying that this fixes this issue. Thanks for taking the time to read this guys - joe

Your post is a little confusing to me... is this in a vehicle? 30 amp low ripple dc switching power supply is an AC to DC converter isn't it? A 4 channel amp does not necessarily give you better sound quality nor does it really increase your volume level. It cuts distortion when you turn the volume up and in some ways yes it does increase sound quality at higher volumes. 30 amps won't fully drive that amp either. You have 3 x 30amp fuses on it. Your balance and fade is a problem and wouldn't help your cause but it could be bad signal wires (rcas), bad amp or a bad source unit (head unit). I would start by checking my polarity of the speaks (yes it matters if even 1 is out of phase), I would pick up a cheap rca to headphone jack (assuming you don't have one laying around) and plug it into the inputs of the amp (connect the headphone jack to your phone) and check all speakers get audio. Then I would get rca couplers and connect it to the ends of your rcas. If all that checks out then your looking at a head unit issue.Thats my 2 cents.... take it for what its worth!

Nothing can replace experience

Probably the smartest person I've talked to out of the 2 forums I've posted about. Thanks for the tips. How would the 30 amps not fully power that amplifier though? It's less than 20 amps continuous and about 22 amps peak and I'm only running 2 channels of the amplifier thus half the power that it could be putting towards. Sure if I got anything more to it I'd have to upgrade. Surely you have something up your sleeve for mentioning that I don't have enough power I'd love to know (not being sarcastic). It's not in a vehicle it's in my bedroom we are using that power supply to use the rest of the equipment in my house. I was thinking about upgrading the head unit anyway so Im thinking about starting there if the problem persists I'll definitely trouble shoot more using your ideas bro. Thanks again man!

daze wrote: Your post is a little confusing to me... is this in a vehicle? 30 amp low ripple dc switching power supply is an AC to DC converter isn't it? A 4 channel amp does not necessarily give you better sound quality nor does it really increase your volume level. It cuts distortion when you turn the volume up and in some ways yes it does increase sound quality at higher volumes. 30 amps won't fully drive that amp either. You have 3 x 30amp fuses on it. Your balance and fade is a problem and wouldn't help your cause but it could be bad signal wires (rcas), bad amp or a bad source unit (head unit). I would start by checking my polarity of the speaks (yes it matters if even 1 is out of phase), I would pick up a cheap rca to headphone jack (assuming you don't have one laying around) and plug it into the inputs of the amp (connect the headphone jack to your phone) and check all speakers get audio. Then I would get rca couplers and connect it to the ends of your rcas. If all that checks out then your looking at a head unit issue.

Hey man I hope you're still around. I tried hooking up the new head unit and it solved the problem with the fader not working right. However it didn't fix the fact that the quality is dog doody. We are thinking it might be the power supply isn't fully powering the units like you said. We are going to take a miltimeter to it and test to see how much power is being pulled from it also we are going to hook up the amp and the speakers ONLY and not the other amp and subs to a higher powered power source say 45 amp this way we can rule out the fact that the amp might be bad.

i went back and forth about commenting about this, I don't want to come off as a jerk or telling you or any one is completely wrong this is only my opinion. I'm not a fan at all of using car audio in the home or the occasional home speaker hooked up to car stereo gear. Car audio is designed to work in a small space like trunks, door panels, a car environment. Home audio is designed in bigger rooms. Why do you think home stereo speaker are in bigger boxes or different ohm loads or even the position of the speakers are in the specific distance between the tweeter and the mid range and the woofer. Higher end home speakers even have the speakers in alignment so the sound travels to your ear at the right times (sound wave maturity), read the car stereo cook book or designing,building,testing your own speaker system book if you really want true knowledge. The displays of car stereo subs i have in my store are trying to fill a in tire store and won't even sound close to what they will in a cars trunk. You could have a million dollar car audio amp running everything in your home and it wont sound as 500 dollar home stereo amp running home stereo speakers. Of course this is just my opinion and you can do what ever you want, but ditch the car audio stuff in home and just buy home gear33 years as a installer now just a retired old guy. Favorite thing to install/topic are remote starts/car alarms. Stop using test lights!!!

Sorry didn't realize you replied. I do agree with the above where you are going to chase your tail trying to run equipment designed for a car in a house. Now I am not saying it can not be done but just may not be worth the trouble. My next guess would be if your having quality issues with sound... it may have more to do with your speaker enclosures than anything else. Back when I was in an installation bay we had a test bench with a source, 2 speakers and a sub and it sounded pretty decent. I would not say it was home theater quality but it was sound.Thats my 2 cents.... take it for what its worth!

Nothing can replace experience

To the OP, why not just throw a car battery in the room to test with? That will rule out your power supply being underpowered for the setup. Since you have a new head unit and you are still having issues, it would be obvious that this is not where the problem is, so could it be the amp is bad? I think the first thing to do at this point would be to check all your wiring again. Make sure the rca cables you're using is good and not shorted or broken electrically. Testing with an rca to headphone jack like Daze suggested would clear that issue up, just use a cellphone or old walkman for sound and see if the amp works better. Also check the speakers. Are they blown? Are they even in a box or some sort of enclosure? And definitely make sure your wiring to the speakers are correct! Positive from amp has to go to positive on speaker, likewise with the negative side! Wiring just one out of phase would make it sound like crap. Having car audio in a home-scenario isn't all that bad, I'm currently using an old Pioneer AVH-X5700 with a 30A power supply which powers 4 Infinity Kappa 62.11I speakers in the ceiling of my patio, but I also built some large sealed boxes for each speaker before the ceiling was closed up! They sound fantastic outside and are way too loud for just a patio system, but my neighbors don't mind it so neither do I! Its not audiophile quality, but its not garbage either. Chris