Contour Enthusiasts Group Archives Forums Modifications Audio Is this correct?

If I power an 8 ohm sub single voice coil (SVC) with an amp rated at 300 W into 4 ohms this sub will provide about the same volume output as a 4 ohm sub powered with an amp rated at 150 W into 4 ohms?

The question is really "if I use a single 8 ohm sub do I need to have an amp that is twice as powerful to get the same output"?

What are the advantages/disadvantages of using an 8 ohm sub vs a 4 ohm?

I will add to this post instead of your previous one. Without getting too technical, yes, it would be similar to running 150 watts to to a 4 ohm sub. In my expierence i have found a the following to be true. In order to get good sound, massive amounts of power aren't always necessary. a quality amp that pushes good quality signals is key, however, if your amp is low power, you will find that if you play it loud for 30 minutes to an hour your amp will be hot and will shut itself off. One thing I know is that lowering the impedence on the speakers can fry an amp because there is less resistance and more current being drawn and the amp will heat up a lot faster (bridging down to 2 ohms when the amp isn't rated for it) I don't know what happens when you do the opposite. Enough rambling, based on the styles of music you are listening to it doesn't seem to me like you are trying to play John Coltrane at 130 db so you may just want to play it safe and spend a bit more money for a 4 ohm sub. If you are trying for a decent amount of thump and the price is really that good, then you should buy 2 of them. They are only 10" subs and I don't know of many people that only use 1 10". A lot of people who use 10's actually go with 3 of them which brings the impedence down to 2.66 ohms

I will add to this post instead of your previous one. Without getting too technical, yes, it would be similar to running 150 watts to to a 4 ohm sub. In my expierence i have found a the following to be true. In order to get good sound, massive amounts of power aren't always necessary. a quality amp that pushes good quality signals is key, however, if your amp is low power, you will find that if you play it loud for 30 minutes to an hour your amp will be hot and will shut itself off. One thing I know is that lowering the impedence on the speakers can fry an amp because there is less resistance and more current being drawn and the amp will heat up a lot faster (bridging down to 2 ohms when the amp isn't rated for it) I don't know what happens when you do the opposite. Enough rambling, based on the styles of music you are listening to it doesn't seem to me like you are trying to play John Coltrane at 130 db so you may just want to play it safe and spend a bit more money for a 4 ohm sub. If you are trying for a decent amount of thump and the price is really that good, then you should buy 2 of them. They are only 10" subs and I don't know of many people that only use 1 10". A lot of people who use 10's actually go with 3 of them which brings the impedence down to 2.66 ohms

I'm sorry, it's early and I just got home a few hours ago from a night of insane drinking, but I didn't notice him mention anything about the sub being 10" He could be planning on a 12", 15", or maybe even an 18". Also, 1 10" is fine if he is going for a SQ setup. that's what myself, and I believe a few others on here are using, and it does the trick.

Cap, you are confusing.

Dickmc, you have an 8-ohm driver. What is the power output of that amp into an 8-ohm load? That is your answer. Depending on the quality of the amp, my guess is 150-200w into 8ohms.

The choice of how much resistance (actually impedance is what counts) depends on how the system is designed. THere is plenty info already written, like this .