So I need some help. I'll make it as easy as possible.
Sitting on a 2 channel 500watt amp here's the specs.
125 watts RMS x 2 at 4 ohms (250 watts RMS x 2 at 2 ohms)
500 watts RMS x 1 bridged output at 4 ohms (4-ohm stable in bridged mode)

And I want to hook it to a pair of 10 inch single voice coil subs. The subs are 4 ohm.
And that's where I'm having the brain fart!
I want 250 watts per sub, but not sure If I can wire them each to a single channel of the amp and get 250 watts.... Since the single channels are 2ohm and these are 4 ohm subs.
Could I wire each sub to the bridged channels and the subs will devide the power? Or will that end up running at 2 ohm. (Amps not stable at 2 ohm bridged)

All I'm looking for is to get the 250watts to each sub.
Does it matter that the channels are 2 ohm and the subs are 4 ohm? Or will the amp cut down the power due to the impedance?

 

Mornin' Steve;

Sorry bud - can't be done.

The most you'll get is 125 per sub.

Bridged? No - if you run them in parallel ( 2 ohms) you'll exceed load specs. If in series (8 ohms) you'll see the same 125 per sub.

And no - does not matter if subs are 4 ohm and the amp is 2 ohm, comparability-wise.

Run each from a separate channel and call it a day, unless you want to spend more money.

 

Thank you so much! That's what I was thinking.... But I figured I was missing something and that it could be done. But I see what your saying. DARN!
Thank you!

Anyone know a good amp that has about the same deminsions of that amp that could get me around 250 rms at 4 ohm on a set of single voice coils?

 

Hi Steve;

How's aboot this'n?

http://www.crutchfield.com/S-WbbJdfq...on-X500-1.html

Real reasonable price, eh?

From Red's build thread: https://www.f150online.com/forums/sp...-upgrades.html

Since it's 500 into 2 ohms stable, you can just parallel yer subs and get 250 per.

BTW - you do know that doubling yer power will not get you double the SPL, aight? Hence, if it were me, I'd try running what you have and see how it sounds, first.

Good luck, bud.

MGD

 

Whats the model number of your amp? If your amp can handle a 2ohm bridged u may be fine.
Also
No, if the amp isnt 2ohm stable bridged it may blow either the amp or the sub and even if you put one sub per channel under powering it will cause the subs to clip which will cause stress on the subs which may lead to blown subs. Not worth it IMO.

 

Haha a Kenwood amp. You'd be lucky to see about 400 clean rms from that. Granted though the price is good considering it's crutchfield.

http://www.crutchfield.com/p_500MRPM...8229025&awdv=c
That's a better quality amp than the kenwood. It'll do right about rated power and it's cheaper too.

But what you said about the spl is definitely true, iirc it's something like double the power net's you about a 3db increase or so.

OP, don't forget the enclosure can make or break it too. You can get top of the line stuff, have a poorly built enclosure or one that's not spec'd to the subs and it'll sound worse than cheapest stuff.

 

Say what? - You talkin' to me? (seeing as you quoted me)

Where did I say anything like that? I simply meant running each sub, as-is, connected to his current amp - one per channel. That isn't going to blow anything - any may in fact sound just fine. You can 'clip' in any configuration, pushed hard enough. The point is to know yer limits and stay below them - in this case, don't overdrive and it will sound fine. And if it does, it certainly IS worth it as he's just saved having to spend more, to gain very little in terms of discernible output, without a very large bump in rated power.

Please clarify yer intent here - thanks.

MGD

 

Thankee, thar son!

I was hopin' y'all would chime in an' hep me

Better tell Red aboot this - save 'im some money!

Steve-O - listen to ol' Peetz - he know'd his stuff!


MGD

 

Hey guys thanks for all the replies!

Maybe it would help if I explain what I'm working on.

I'm building a system for a buddy, he's on a little bit of a budget. And so far we've done an amazing job for very cheap.
Right now I'm loading 2 rockford 10 inch p1's into a costom built sealed enclosure. Spec on the subs calls for .59 feet of air, and that's not after displacement. So the actual cubic feet was about .54 of air space. But they sounded a bit tight and punchy. I built the box to .62 cubic feet (after sub displacement) and did a test run and they actually sounded great! I wasn't expecting much from these p1 entry subs. But they surprised me. I tested them with more power than they should have. But I was only trying to hear how they sounded with the air space modifications.
The amp he is planning on using is a antique xplod 800 2 channel that has seen better days. Out of the 170 watts per channel it should deliver..... I bench tested it at 104 watts per channel. And I'm not sure I trust this ancient thing anyway.
I'm looking for a decent (true) 250 rms per channel to run these 4 ohm SVC subs. It's a little on the high side for these subs, but with power loss and wiring, it should put me where I want to be.
I gave these things a test run at 400 watts a piece. So I figure I'll probably have a 5-8db loss with only 250 watts. Give or take?...
The enclosure is perfect. Now I just need a decent amp. And to make things worse, space is a factor. This amp is gonna have to fit under the seat. And I've already got a 300 watt 4 channel under the passenger seat running the mids and components. All this is going in a super cab pickup. If I have to lift the seat.... I will. But I need something decent that will drive alright.
The dimensions of the rockford 500.2 were perfect. It was a tad wider than I wanted, but it worked fine. I'm just trying to figure out a reliable amp for these things that isn't gonna break the bank. $140-$160ish I guess.

Any of that help? Got any ideas? I appreciate all the help and advise.

 

So it sounds like you need a 500 watt @ 2 ohm mono block sub amp. This is a smokin deal right now.

http://www.crutchfield.com/p_500MRPM....html?tp=35834

If you need something with a smaller foot print you could give this 1 a try.

http://www.crutchfield.com/p_236TD1K....html?tp=35834

 

I like the alpine. I saw this amp the other day on the same site... But it seems a little under powered, doesn't it?

I like the idea of the MTX just for the sake of plenty of power for down the road. Everybody upgrades at some point.
Isn't the 1000.1 a little much for the subs I'm driving? They are 300 (peak).
I don't want to over drive them. Rockford entry subs don't like being over powered.

However the alpine doesn't seem like it's got enough power per channel when it's all said and done.

Am I right? Or way off?

 

If you plan to give them 250 watts rms and each sub is single voice coil 4 ohm, the alpine amp will be fine, peak ratings literally mean nothing, don't pay attention to those.

If you want more power the mtx amp will work. But don't expect to see the full rated power out of it, and you'll need to keep the gain cut way back so you don't damage the subs.

 

If each sub can handle 250 watts then you need a 500 watt 2 ohm stable amp. At the split volts remains the same while current with divide. You can easily give them more power as long as it is clean with minimal distortion. A 100 watts over is not to big of a deal if it clean. Digital mono blocks will have the small foot print you are looking for with the power you need. You can find a a crap load on Ebay. You can even find factory refurbished with 3 year factory warranty's that will same a bunch of money. When a amp is factory refurbished it must meet original specs and a 3 year warranty is better than most places new.

 

That's what I was thinking my friend...... However I've been out of the game for awhile. Have played with the new products in awhile. And I know how it is in the audio world,,,, some stuff is great and other stuff is crap.

Any advise on what's decent right now? I hear lots of amazing things about sundown audio. However that's more than my buddy wants to spend. I like the idea of the MTX 1000 from an earlier post. The alpine is good too and I read good reviews, but if there are other areas that I can look, that would be awesome.

All I'm looking for is 250 (true) watts to each sub, 4 ohm. I completely agree that a mono amp is best for this application... And they are smaller which is great.
I was planning trying to buy from ebay.... It's so much cheaper than the sound shops in my area.

I really appreciate all your help and advice guys.
When it comes to instal and design and wiring and building enclosures and tuning.... I have no problems. But when you've been out of the loop for a while (17 year) it's hard to tell what's quality and what's junk. A lot has changed.
Thanks a million guys.

 

Personally I would go with the planet audio. Big bang for the buck and I know its more ower than you need but you can always turn it down. I run them in my truck and am happy with them. Plenty of power and I know they work great. It is stable down to 1 ohm. The larger amp and the 1 ohm stable make it a nice candidate for future upgrades. It's been my experience thatmost people will want more in the future, It's just a matter of time.


http://www.ebay.com/itm/SOUNDSTREAM-STL1-600D-600-WATT-RMS-CLASS-D-MONO-AMPLIFIER-MONOBLOCK-AMP-1200-MAX-/161131151047?pt=LH_DefaultDomain_0&hash=item25842a3ec7http://www.ebay.com/itm/Planet-Audio-AP1500D-1500W-Peak-1000W-RMS-Class-D-Mono-Amplifier-Car-Audio-Amp-/390658738894?pt=Car_Amplifiers&hash=item5af5134ace&vxp=mtr