:redface: Ok here goes.. I recently purchased a mono block amp and it was powering my 2 12" pioneer subs.. I got it tested and was reading 143.7db. pretty good i thought as they were 3yr old subs. Then i just updated to dual voice coil 12" alpine subs and i got a reading of 133.1db. I was curious as to why this would be.. My mono block is a 700w and i thought this would power them good. But someone told me that cause it running 2 subs that the power was now 350w per sub. when they have compassity for more.. Is this true or they pulling my leg.. Can anyone explain in normal terms to me what is happening. As i feel as though i have made a huge mistake in changing subs.. Please some one help...

I don't know how to explain it exactly, but they will definatly perform better with another amp.

This is Bizzare but I have a Theory..
Theory 1.
Your Enclosure is not suited to your New Subs.

Theory Two
You have gone to Dual Voice Coil subs, Depending on What Ohmage they are, will depend if your Amp will be seeing a Higher or Lower Ohmage therefore Reducing Output.. As I said it is a Theory not fact.

Also try flipping the positives and negatives over on just one of the subs. At just one end though.

Were both readings from the same dB reader?

Alpine love power. Pioneer are more "mass produced" material every second car has. Alpine price themselves out of this category.

New enclosure and make it one amp per sub and you should equal, or maybe top by a few dB that reading.

What voice coil subs? What is your amp loaded down to?

What power does your amp put out at that load? Have you set your gains properly?

Are your subs wired up in phase?

I have two Clarion Dual Voice Coil Subs and an Alpine 990W Mono Block Amp, I rang up the local audio installer and seller of Alpine and asked how to hook them up.

He also stated that the amp will not run at its full potential as my subs are 4ohm and the amp is 2ohm, get this though, My brother has 2 dual voice coil Alpine Subs and the same amp running them both and they are 2ohm a voice coil and they sound great. I think it all comes down to technology as well as the right ohmage. Since my Clarions are 3 years old they have probably reached the end of life. So i am going to buy 2 new Alpines and hook them up.

What i am trying to say is that the amp wont put out the max because the load is higher on the amp. If you hooked up 2 single voice coil subs to it then they would pump. But for dual voice coil if you have the space and money you probably want 2 amps or a bigger single one that can handle ya subs.

Oh and another thing apparently running one voice coil can damage ya subs..... I ran one on each sub for 3 years and they are still going. But that is what i was told by the guy at the HRC in town (Hobart)

Theory 1: Old subs where measured on Audiocontrol because even 2x 305c and 306c Pioneers have only pulled just over 140db on termilab with a huge box and 1000 odd WRMS each. Hmmm only 10db difference so the old subs where twice as loud lol .

Theory 2: You have bought DVC 4ohm woofers and your amp is not 1 ohm stable therefore they are only getting half - three quarters the power.

Theory 3: We need a bit more info to solve your delemer :D To help us out can you please tell us:
*Are they using the same enclosure and if so what size per chamber is it and is it ported / sealed etc. If different what were the old one in and what are the new ones in?
*What model Alpine subs are they? Type S / R / X and are they DVC 4ohm or 2ohm?
*What model amp are you using?
*Who installed it?

Thanks :D

Theory 1: Old subs where measured on Audiocontrol because even 2x 305c and 306c Pioneers have only pulled just over 140db on termilab with a huge box and 1000 odd WRMS each. Hmmm only 10db difference so the old subs where twice as loud lol .

Theory 2: You have bought DVC 4ohm woofers and your amp is not 1 ohm stable therefore they are only getting half - three quarters the power.

Theory 3: We need a bit more info to solve your delemer :D To help us out can you please tell us:
*Are they using the same enclosure and if so what size per chamber is it and is it ported / sealed etc. If different what were the old one in and what are the new ones in?
*What model Alpine subs are they? Type S / R / X and are they DVC 4ohm or 2ohm?
*What model amp are you using?
*Who installed it?

Thanks :D


Ok here is what i know.. They are 2 x12" alpine dvc type S 2ohms. the amp is a alpine vpower MRP-M350 mono block with 700w max power. Box is not ported its sealed. te amp is running at 2ohms.. I was thinking that maybe my prob is they need to be run in more yet

Ok here is what i know.. They are 2 x12" alpine dvc type S 2ohms. the amp is a alpine vpower MRP-M350 mono block with 700w max power. Box is not ported its sealed. te amp is running at 2ohms.. I was thinking that maybe my prob is they need to be run in more yet

ok well forget max power. I have that same setup except i have the MRD-M301 which has the same power as the MRP-M350. @2ohm's that amp makes 350wRMS, which is only 175wRMS to each sub. Those subs can handle 350wRMS+ each.

Still strange that your pioneers were louder off the same amp though? Exactly how have you wired the subs up?

ok well forget max power. I have that same setup except i have the MRD-M301 which has the same power as the MRP-M350. @2ohm's that amp makes 350wRMS, which is only 175wRMS to each sub. Those subs can handle 350wRMS+ each.

Still strange that your pioneers were louder off the same amp though? Exactly how have you wired the subs up?

Damn this **** sux.. I have no idea to be honest.. I let my partner put them in.. As i was cleaning engine bay.. Naughty girl i know.. How should they be wired?? please help.. If you can. Add me if easier to talk..

Mel

Damn this **** sux.. I have no idea to be honest.. I let my partner put them in.. As i was cleaning engine bay.. Naughty girl i know.. How should they be wired?? please help.. If you can. Add me if easier to talk..
Mel


they should be wired like this:

and thats copied straight out of the manual for the dual 2 0hm Alpine subs i bought recently

With DVC subs it is easiler to have 1 wire coming from each sub. In your situation you want to wire each sub in series to make a 4ohm load. Do this by taking one length of wire and join the +ive terminal of one side to the -ive terminal of the other. Then vica versa. You now should have wire going from one side to the other and both subs presenting a 4ohm load. I think on the new type R they are next to each other so just do the same thing, one coil is the +ive and -ive on the right and the other coil is the +ive and -ive on the left.

Now from one of the terminals attach the wire as you would if it was a Single voice coil, i.e. one to the +ive and one to the -ive making sure you so the same to both subs. It does not matter which terminal you use as long as they are the same pair.. i.e next to each other. Then join both the wires that have the line of them together and both the wires that dont have a line together and this will produce a 2ohm load. Then wire it to the amp. :D

Combination of under powering the subs and if there very new alpine subs, they like time to break in.

Get a MRD-1005 if you want to get the most potential out of those subs.

my type s alpines were gutless for a while till i ran them in i had one 300watt alpine mono block amp running 2 type s 350watt subs and it was pretty awsome.

i forgot to add that i was very disappointed with my alpines when i first hooked them up, and then over the space of about an hour they got progressively louder and louder :)

:bowrofl: Thank you all for your advice. i will be pulling system apart and re wiring it to be safe.. And i will give them time to wear in.. And get it tested. but yes I think i will have to purchase another amp though.. All the same. thanks again for all the help.. This is why im gad i joined our lil club.. Will let you know how it goes..

Mel

Run it time is crap, waited 50hrs to crank my G5... it was so worth the wait... my shed 50m away rattles, i like that :badgrin:

Glad to help anyone on here, that is why it is good to ask questions even if you think they are silly question. :D