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Some wiring / speaker wattage questions
Posted: Thu May 25, 2006 5:19 pm
by Rivers
Couple of questions folks:
1. For 8 ohm speakers that are going to be drawing power from a 4 ohm amplifier, does it need to be wired differently?
2. I see a couple of posts about giving extra wattage to speakers which results in a increase in db levels. On the flip side, if I am not after SPL, is there is a minimum amount of power that is required for the speakers to sound optimal? I read somewhere else that tweeters at 15 watts can generate quite a load db-wise. Having extra headroom is always a good thing I suppose, but what would be a rough minimal gauge for it to sound optimal?
Posted: Thu May 25, 2006 5:29 pm
by Ryan from Ohio
Ohms reffers to what an amp will see, which will vary depending on how you wire.
So if your speakers are 8 Ohms and ytou run each one into the amp thats what the amp will see. Likewise if you amp is rated @ 100 WRMS into 4 Ohms and you give it 8 Ohms the power output will drop to 50 WRMS...
You usually want to give speakers about 70-90% of rated power.
Posted: Thu May 25, 2006 7:01 pm
by Rave'n
If you wire them together in series it will bring the impedance on the amp down to 4 ohms.
Still dont know how to post pics.lol
http://www.rockfordfosgate.com/home/
^^ This site can help you with wiring them together.
Posted: Thu May 25, 2006 7:16 pm
by Rivers
Eh? I am getting a little confused. So I have to wire them in series so that the amp will supply 4 ohms to the speakers?
Posted: Thu May 25, 2006 7:26 pm
by Rave'n
No, you wire the speakers to 4 ohm then bridge your amp.
Ohm's refer to the impedance on your amp.
Higher the impedance the lower the power to the subs will be.
Posted: Thu May 25, 2006 7:33 pm
by High Society
Also, are they single 8ohm, dual 8 ohm? How many subs do you have? What kinda amp?
Posted: Thu May 25, 2006 7:36 pm
by Rivers
These are 7" drivers, single 8ohms. Powered by a 4-channel amp that does 60w at 4 ohms. I am not planning on bridging the channels as 2 of them will be powering my tweeters.
Posted: Thu May 25, 2006 7:47 pm
by High Society
well you will be gettin low wattage from that amp at 8 ohms.....Whats the rms on the woofers?
Posted: Thu May 25, 2006 7:48 pm
by Rave'n
what ohm and rms are your tweeters?
your speaker should be fine.
Posted: Thu May 25, 2006 8:23 pm
by Rivers
tweeters are 4 ohms, max rms should be around 200wrms, long-term usage should be around 100wrms?
long term usage for the 7" drivers is 80wrms.