wiring help

[magilla]

i have a sunn 2 x 15 cabinet that i blew the speakers in because i'm an idiot.
i got some new speakers that are 8 ohms and the old ones were 4 ohms

do i need to change the wiring in the cabinet?

any help is much appreciated

[JoeArthur]

Are you saying that both of your old speakers were 4 ohms each, or that the total cab ohms was 4 ohms?

[magilla]

well
all i know is that on that back plate where the jack is
it says 4 ohms
thats all i know
does that mean that the speakers that were in there were 2 ohms
which adds to 4
so i'll be running 16 ohms?
does it add up like that?
i'm confused

[Johann]

the speakers inside were probably both 8 ohm speakers wired parallel to each other, so by putting two new 8 ohm drivers in it would remain 4 ohms, or by putting two 16 ohm drivers in it would increase to 8 ohms without rewiring it

[magilla]

damn
ok
so how do i know if they are wired parallel?

and if i re wired it could i get it to push both at 8 ohms?

there is 3 jacks on the cabinet
i don't know what the other 2 are
i also have like 4 or 5 jacks on my head

i really don't know anything

thanks alot for the help

[Isaac]

There is no practical way to wire two 8 ohm drivers for a total 8 ohm load. Forget that path.

Parallel means that the electricity goes to both drivers at the same time. Series means that it goes through one before going to the other. Here are some diagrams to explain:
http://www.avatarspeakers.com/wiring%20diagrams.htm

[magilla]

oh
thanks for the diragram
that helped alot
i guess i'm screwed then
do you think it would hurt to run 2 x 8 ohm speakers in parallel
that handle 300 watts each with a 250 watt head?
i'm kinda thinkin that it will be ok
lets hope so
thanks alot for the help

[Isaac]

You should be fine. Remember, a speaker's power rating is how much it is rated to handle before bad things happen. Putting less power into it is fine. If it weren't, bad things would happen every time we turned the volume down on our amps.

[JoeArthur]

oh
thanks for the diragram
that helped alot
i guess i'm screwed then
do you think it would hurt to run 2 x 8 ohm speakers in parallel
that handle 300 watts each with a 250 watt head?
i'm kinda thinkin that it will be ok
lets hope so
thanks alot for the help

Telling you how to wire speakers of a specified impedance to achieve a total impedance is relatively simple.

Your last question is much more complex.

Are the "watts" ratings the same? While there is an electrical definition of "watts", manufacturers do not agree when it comes to rating their amps and/or speakers.

For example, you can find speakers rated in "RMS", "continuous", "program", and the most nebulous of all "peak" watts... just to name a few. Amplifier makers play the same game.

So at least tell us what amp and speakers we are talking about, or better yet provide a link to them so we don't have to waste our time searching for some info about them.

[Isaac]

Joe, everything you say is true, of course, but unless he's running the amp all out, all the time, I really don't think it's going to matter all that much. If the amp is 250 watts RMS, and the drivers are 300 watts each, peak, they're still likely to handle at least 100 watts each RMS. Add to that the fact that music ebbs and flows, notes having attack and decay, spaces between them, rests and breaks in the songs, and breaks between songs, and I just can't see him overpowering the drivers unless he's fully clipping the amp.

[JoeArthur]

Joe, everything you say is true, of course, but unless he's running the amp all out, all the time, I really don't think it's going to matter all that much. If the amp is 250 watts RMS, and the drivers are 300 watts each, peak, they're still likely to handle at least 100 watts each RMS. Add to that the fact that music ebbs and flows, notes having attack and decay, spaces between them, rests and breaks in the songs, and breaks between songs, and I just can't see him overpowering the drivers unless he's fully clipping the amp.

I understand what you are saying.

It is still only an assumption (since there are no specifics) that there is something reasonable and logical between a "300 watts unspecified" that converts to a "100 watts RMS" rating.

I've seen a measured 10 watts rms rating advertised as anything between 10 to 500 watts. Both speakers and amps.

But I do agree... that a lower wattage amp at full clipping can destroy speakers of higher power handling - even where the rating method is the same.

One thing that still cracks me up - is to see an amp advertised as "400 watts" and it only has an eight inch speaker!!

[basiklybass]

Even better is to see amps rated at 400 or 600 watts....and the power consumption is only 95 watts. I have been thinking about hooking these up to my house....if they use 95 watts and produce 400....I think I can save the world and solve the energy crisis. Just a bit of re-wiring....hook this thingy up over here......I'll let you know how it turns out.

I also wonder about power ratings on speakers. Just because they manufacturer says they'll handle 300 watts....don't make it so. A young neighbor bought some car subwoofers telling me they handle 1200 watts each, hooked them up to some amp that claimed 400 watts.....only used 150....and promptly blew the speakers apart after 15 minutes of playing his bass through them. I don't know what they were....just that one should stick to major, well known manufacturers.....and leave yourself some wiggle room. 2-300 watt speakers with a 250 watt head.....I'd go for it. Course, I don't mind playing with my gear....and am blessed with the funds to allow such play. Maybe it's just cause I'm old.....er

[magilla]

ha ya i'm a youngin i guess

should i go for wiring them in series?
would that help at all?
i'm planing on getting a 300t soon hopefully

and as far as the speakers go i don't have them yet and when
i bought them the guy just said they were 300 watts
i'll know when they get here in the next couple days

[djc]

ya, watch out for the power rating, my 410 cab theoretically handles 1200watts suposedly RMS, my 65watt (on a scope) 200S can hurt them ie bounce them off the cage and at length would destroy the cab.  8 is as high as I'll go, it'll kill drummers and sound great, but no way would I throw 1200 watts into it.