Ok. I am thinking of buying the Alpine SPR-17S 6.5" splits that I mentioned in another thread. They run at 110W RMS. Now, that I have made my decision as far as splits go and I have almost made up my mind on what 12" sub I want, I need to decide what amps to power them with. I have some lower power Pioneer 6x9s for the back that I am salvaging from my current car. It isn't ideal, but it is keeping costs down. I'll upgrade them later on.

Now I am unsure what sort of amps I need. Do I need a 2ch or a 4ch for the splits and 6x9s? I thought 1ch per set of speakers, but I am far far from any kind of expert so some enlightenment would be great.

If it is 2ch, Jaycar has a 2ch Amp Link (http://www.jaycar.com.au/productView.asp?ID=AA0424&CATID=24&keywords=&SPECIAL=&form=CAT&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=595) that is 150W per channel at 4ohms which these splits and the sub I want are. I was wondering if it is possible to run the splits off one channel, the 6x9s off the other, and then buy a second amp, and bridge it to get the power I want for the sub.

Is this possible? All the speakers I have/want are 4ohms if that makes a difference.

4channel amp for all the speakers so you can control everything and a 2ch amp for your sub.

Ideally, use a 4 ch amp to run your front active however your xovers that you get with them do not allow you to do that and run the rears off the deck ( as long as you can HP them ). *custom xover* I would be cautious giving the Alpines 110WRMS, even there Type X don't have power ratings that high...

Ideally, use a 4 ch amp to run your front active however your xovers that you get with them do not allow you to do that and run the rears off the deck ( as long as you can HP them ). *custom xover* I would be cautious giving the Alpines 110WRMS, even there Type X don't have power ratings that high...

So what cheaper amp would you recommend for the splits and 6x9s? What about this one (http://www.jaycar.com.au/productView.asp?ID=AA0426&CATID=24&keywords=&SPECIAL=&form=CAT&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=595) or is it to powerful for my needs?

Yeah that amp will be good. You wont need all that power but it will be handy in the future. My mate has one running the older Boston FS-60's and a sub. Plently of power and ample xovers for a 3ch configuration. Just don't turn the gains up to high...

i just happen to be selling my jaycar amp,http://www.aussiemagna.com/forums/showthread.php?t=48355 was used for about 5 months before removal

So do I need anything special to bridge the 2ch amp for the sub? Also, my 6x9s are salvaged from my old car to save money, they are something like 45WRMS, could they still be connected to the amp if I turned the gain way down? Can I connect it to the HU and leave 2 channels un-utilised without damaging anything?

So do I need anything special to bridge the 2ch amp for the sub? Also, my 6x9s are salvaged from my old car to save money, they are something like 45WRMS, could they still be connected to the amp if I turned the gain way down? Can I connect it to the HU and leave 2 channels un-utilised without damaging anything?

Yes you certanly can. You will turn the rear gains down anyway to keep your front stage imaged good.

You will actually have all 4 channels of your headunit amp disconnected, doesn't hurt anything as long you dont leave them bare! Heatshrink or at least electrical tape the ends.

The reason why I suggested a 2ch amp for the sub is because with only one sub that is SVC 4ohm you are best to run with a 2ch amp. To bridge it the amp will show you where to put the wires. If you where to get a DVC 4ohm sub then a monoblock that makes its power @ 2ohm would be your best bet.

If you where to get a DVC 4ohm sub then a monoblock that makes its power @ 2ohm would be your best bet.

This is where I get confused. I saw a Clarion Monoblock which generated 300WRMS at 4ohms but 400WRMS at 2ohms. The sub I am looking at is 4ohms. So wouldn't I be underpowering it because it is a 4ohm sub?

I understand what impedance is, but I am still trying to grasp it in relation to audio products.

This is where I get confused. I saw a Clarion Monoblock which generated 300WRMS at 4ohms but 400WRMS at 2ohms. The sub I am looking at is 4ohms. So wouldn't I be underpowering it because it is a 4ohm sub?

I understand what impedance is, but I am still trying to grasp it in relation to audio products.

Well you could still get the above mono block but for the money, you get a better sounding, more powerful 2ch amp for less money. What sub are you planning on getting?

Well you could still get the above mono block but for the money, you get a better sounding, more powerful 2ch amp for less money. What sub are you planning on getting?

Pioneer 307D4

I was going to get a monoblock, but yeah, I think a good 2ch amp would be better.

rule of thumb
you are better off running 1000wrms through a set of speakers rated at 10wrms than 10rms running through a 1000wrms speaker
basically the more power you can give you speakers the more headroom you have in tuning and expansion and the less chance you have of the AMP distorting (clipping) killing your speakers
this is true for both full range and subs

bang for buck there are no better amps than jaycar response

rule of thumb
you are better off running 1000wrms through a set of speakers rated at 10wrms than 10rms running through a 1000wrms speaker
basically the more power you can give you speakers the more headroom you have in tuning and expansion and the less chance you have of the AMP distorting (clipping) killing your speakers
this is true for both full range and subs

bang for buck there are no better amps than jaycar response

Those jaycar response amps are just awesome.
I kane them things so very much, have them kept in a tiny space, and never do they overheat, cut out, nothing.
If your budget conscious go response for sure!

rule of thumb
you are better off running 1000wrms through a set of speakers rated at 10wrms than 10rms running through a 1000wrms speaker
basically the more power you can give you speakers the more headroom you have in tuning and expansion and the less chance you have of the AMP distorting (clipping) killing your speakers
this is true for both full range and subs


Thanks, that was helpful since I wasn't sure if overpowering or underpowering causes clipping.

overpowering your amp causes clipping

overpowering your amp causes clipping

Do you mean stressing? When I talked about overpowering or underpowering in a previous post, I meant the speakers.

Do you mean stressing? When I talked about overpowering or underpowering in a previous post, I meant the speakers.

You must remember that speakers are only the bit that reproduces sound. A 100WRMS woofer wont care if it is fed 1W or 200W. It is all about making sure the amp is set up to make the power at safe levels. You can have distortion and not hurt your speakers.

Basically what will have with clipping is you will drive your speaker to the point that the coil will heat up and melt. How this will happen is if the amp is being driven to make a lot more power than it can cleanly, i.e. driving a 200WRMS to 400WRMS, a clean sine wave will then slowly become a square wave. This will mean that there is a time when the coil will be stationary and the heat will not be properly dispersed. This is why you can do short SPL bursts without blowing up anything. With a clean sine wave, as the woofer moves up all the cool air gets drawn in and as it comes to rest, it will push the hot air out. Obviously if the woofer has some hang time ( square wave ) with a lot of heat, melting might happen and the woofer damaged. :cry:

You must remember that speakers are only the bit that reproduces sound. A 100WRMS woofer wont care if it is fed 1W or 200W. It is all about making sure the amp is set up to make the power at safe levels. You can have distortion and not hurt your speakers.

Do you mean setting the gain on the amp?