Understanding OHMs has hurt my head! HELP

[knokinnakamichi 10+ year member]

OK, I'll try and keep it short. I currently have 2 dayton 10" HFs (SVC-4ohms) hooked up to a PA-2004 using the mono pass only, first sub ch1 pos, ch2 neg, sec sub ch3 pos, ch4 neg...am I running my amp at 2ohms or 4 ohms? BC I don't think my amp is stable at running 2ohms-it was quite hot today! Someone on here told me I was good, but after some reading I'm not so sure.....if I get a mono block like the Rockford Fosgate T10001bd Class D Amp or the Phoenix Gold RSd 600.1 Amp how does that work for two subs? I'm looking to get a class B/D mono amp to get about 350-400 rms x 2 for my 2 SVC 4ohms, bc my amp is getting way too hot for comfort AND I'm ubber confused about all this...and help is appreciated!

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[MisterDeadeye 10+ year member]

Your 4 ohm subs are wired at 4 ohms................. It's the only way to wire them.

Nakamichi says that the amp is okay to run as a two channel. What do you mean by quite hot?

How did you set your gains?

 

[goingdef 10+ year member]

if it's a ab class amp they get warmer then bd/d class amps when you run them full tilt for any length of time and with the way you have wired up the 2 subs to 4 channels the amp is seeing a total ohm load of 8 divided across 4 channels gives you 2 ohms per channel.

 

[itsblown 10+ year member]

always remember this 1/(1/Impedence of woofer+ 1/impedence of other woofer)

 

[knokinnakamichi 10+ year member]

Well I spent under an hour setting my gains to some various tracks, and with my HU (KDC-X695) at peak volume and pumping surprisingly a death metal track ("American Capitalist" by Five Finger Death Punch) I got the most distortion over my rap/hiphop...my input sensitivity is currently set right between the 8v and 190mv with low pass at about 60-65....I mean it was burning up when I drove back home, so about an hour!

 

[knokinnakamichi 10+ year member]

if it's a ab class amp they get warmer then bd/d class amps when you run them full tilt for any length of time and with the way you have wired up the 2 subs to 4 channels the amp is seeing a total ohm load of 8 divided across 4 channels gives you 2 ohms per channel.

YES! This is what I thought, so my amp is running at 2 ohms per channel....not good for it, correct? How could I rewire, or should I try and find a B/D? I love the SQ of the nak though!

 

[brooklynjoy2008 10+ year member]

Yeah you should also check your grounds, unless your amp is bad that is not your problem. Does it go into protect? And if you u have a dmm check your voltage at full tilt. It may be a pia but you should check that all of your connections are tight and secure.

 

[stl_314 10+ year member]

Its ok at 2 ohm per channel. You dont want to run it bridged at 2 ohms.

In other words you are bridging the frontand back channels at 4 ohms each. Which is perfect.

And you probably have your gain too high if its that hot

 

[MisterDeadeye 10+ year member]

if it's a ab class amp they get warmer then bd/d class amps when you run them full tilt for any length of time and with the way you have wired up the 2 subs to 4 channels the amp is seeing a total ohm load of 8 divided across 4 channels gives you 2 ohms per channel.

He has the 4 channel bridged into a two channel. Each bridged channel is seeing a 4 ohm load.

always remember this 1/(1/Impedence of woofer+ 1/impedence of other woofer)

He's wiring his SVC subs separately. This doesn't apply.

Well I spent under an hour setting my gains to some various tracks, and with my HU (KDC-X695) at peak volume and pumping surprisingly a death metal track ("American Capitalist" by Five Finger Death Punch) I got the most distortion over my rap/hiphop...my input sensitivity is currently set right between the 8v and 190mv with low pass at about 60-65....I mean it was burning up when I drove back home, so about an hour!

There's your problem. Set your gain correctly and stop ruining your shit.

YES! This is what I thought, so my amp is running at 2 ohms per channel....not good for it, correct? How could I rewire, or should I try and find a B/D? I love the SQ of the nak though!

No. The subs are 4 ohms. Don't let retards tell you the wrong thing.

 

[knokinnakamichi 10+ year member]

Yeah you should also check your grounds, unless your amp is bad that is not your problem. Does it go into protect? And if you u have a dmm check your voltage at full tilt. It may be a pia but you should check that all of your connections are tight and secure.

It only went into protect when I was playing the "American capitalist" jam at full volume with the gain where it is currently set, but this was after about 25-30 mins of full volume. All my connection are secure, I checked multiple times during install. I drilled my own hole for my ground, the only thing that MAY be an issue is the power cable connected to the fuse under the hood has some extra wiring hanging out, but is secured great and wiring is covered (I could get a pic of what I am referring too, but I'm sure it's golden). Why would connections be an issue-I think it's just a A/B issue? what is "pia"?

 

[VisceralSound 10+ year member]

Deadeye is giving you the right advice. Set your gains right and you'll be good.

 

[knokinnakamichi 10+ year member]

There's your problem. Set your gain correctly and stop ruining your sh

Ummm please explain? I read multiple different articles and it explained to do it this way.....so please enlighten me..

And my subs are connected just like this http://a248.e.akamai.net/pix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/2SVC_4-ohm_4ch.jpg

 

[MisterDeadeye 10+ year member]

Ummm please explain? I read multiple different articles and it explained to do it this way.....so please enlighten me..

The articles told you to move around your gain aimlessly? You need to set it correctly. Either take your vehicle to an audio shop and pay them to use an oscilloscope, or buy a digital multimeter and set them that way. Your amp might be overworking itself, hence the extra heat. But remember, the metal casing around your amp isn't just to protect it from a beating. It is supposed to absorb the heat, moving it away from the circuit board.

And my subs are connected just like this http://a248.e.akamai.net/pix.crutchfield.com/ca/learningcenter/car/subwoofer_wiring/2SVC_4-ohm_4ch.jpg

Exactly. 4 ohms = 4 ohms. What's the problem?

 

[VisceralSound 10+ year member]

The articles told you to move around your gain aimlessly? You need to set it correctly. Either take your vehicle to an audio shop and pay them to use an oscilloscope, or buy a digital multimeter and set them that way. Your amp might be overworking itself, hence the extra heat. But remember, the metal casing around your amp isn't just to protect it from a beating. It is supposed to absorb the heat, moving it away from the circuit board.


Exactly. 4 ohms = 4 ohms. What's the problem?

Lol, everytime someone posts an Audio Shop set their gains, they say that they turned it up until they could hear distortion then turned it down a little and said "your good"

 

[MisterDeadeye 10+ year member]

Lol, everytime someone posts an Audio Shop set their gains, they say that they turned it up until they could hear distortion then turned it down a little and said "your good"

Yeah, if the audio shop you go to doesn't have an oscilloscope, or doesn't even know what you're talking about, turn around and run.