RE8 not playing as well as expected, few questions.

[xmakeafistx 10+ year member]

I'm probably taking this up to user error, because it seriously sounds like my door speakers are doing better with the lower frequencies than the RE8 is. I put this into a ported box, 1.3 cubes total (1.2 after displacement) the port is tuned to 34hz I believe. I was thinking maybe the box is just a tad too big?

I also checked the impedance of the sub, and when I put the multi meter to the amps speaker terminals it gave me some crazy high numbers, like in the 20's and up, at the time my amp was unplugged to a power source.

When I checked the impedance without the amps speaker terminals, it came out to only 6.5. (I checked the impedance of both coils, they are 3.8 each, trying to get it to be near 8 ohms)

So it seems like there is a lot going on here, and i'm not sure what to quite pin it on.

Here is photos of the subwoofer box, and how the wiring is done.

My main questions here are...

1. Is my box too big for this sub?

2. How can I test my amp using a multi meter to see if there is something wrong with it?

3. Are the connectors I used for the speaker wire bad to use?

4. Why is my impedance so low?

5. Is there any other errors you can spot out?

Thank you everyone in advance for your help and I apologize if I have not been clear. I'm free to answer any questions that could help me.

Click to read more...

 

[dumple 5,000+ posts]

is it me or does that port look tiny

 

[xmakeafistx 10+ year member]

its a little more than a half inch wide.

 

[dumple 5,000+ posts]

what are all the dimensions of your box

 

[xmakeafistx 10+ year member]

16w x 12h x 12d

this includes the port.

 

[dumple 5,000+ posts]

what are the dimensions of the port

 

[dumple 5,000+ posts]

16w x 12h x 12d
this includes the port.

if it were completely sealed this box would be less then 1 cube, so with the addition of the port your sub is in a box less then maybe .85cuft

 

[xmakeafistx 10+ year member]

My friend and I must have calculated Everything wrong... I think we forgot about inside measurements etc. hmm. Wouldn't .85 cubes still be okay for this woofer? I'm unsure..

 

[dumple 5,000+ posts]

well I can almost guarantee that port isnt 34 hz

 

[ace_800 5,000+ posts]

Ports way to small. How long is it? You need at least a 2" port, but .85 should be fine for ^3

 

[Imtjnotu 5,000+ posts]

For one the port is too small way too small

Also do u even kno what ur amp puts out at 8 ohms it could be next to nothing

 

[duanebro 10+ year member]

The port is to skinny, and you have a problem with your wiring. You should have the same resistance at the amp as at the sub. I'd first try to get rid of the connectors. Twist the wires together, and of course rap them in tape or a wire nut. Try it again. If it is better then replace the wires with longer ones so you don't need connectors.

I'd think your box will have a very high resistance in the port. As you turn up the power it will act more like a leaky sealed box than ported. You might have to go to more of a square port, or a round port, to make it work. And as others have said, the tuning is going to be off do to the box miscalculation.

 

[xmakeafistx 10+ year member]

My amp is supposed to put out about 600w at about 4 ohms. so i'm playing it safe with this sub.

Also, Thank you very much the post above, I'm thinking about replacing the piece that has the cutout of the sub and make a different one.

What would be your opinion on replacing the cutout piece and making another one with a round port in it? what size port would you suggest?

Also, I believe the connectors are also causing a problem. I don't know how my impedance lowers, because both coils alone are 3.8. I'll try cutting down the electrical variables tomorrow.

I put the multi meter to my amps speaker terminals and its giving me an insane impedance. i'm getting like 300 some ohms. I tried probing it on the inside of the terminal and still got same results, could this be a problem with my amp?

EDIT: My ohm reading at the amp is the one thats getting 300 ohms, I'm getting a smaller reading when I probe the wires themselves. (6.5 ohms) just to make myself clear.

 

[audiobaun 5,000+ posts]

I would recommend for a quick fix if using same box,just put a new face, and do the cut out for the sub...1/2in or 5/8,so you dont rebuild the box.I recommend using approx a 2in round port approx 6 3/4 long.IMO.Id test it sealed also see how it sounds to you before porting.Be an oppritunity to double check the wiring config of the sub too, in making sure you have wired it to the right ohms load as well.Just my suggestions.4ohms is the min Id like to be at.

 

[xmakeafistx 10+ year member]

Thats what I was planning to do ^ Thanks for the port info though, thats probably what i'm going to end up doing. I've double checked the wiring config a million times now, it has to be the connectors I used, or possibly a loose connection at the speaker terminals.