Power needed for DVC subs in parallel

I have 2 Alpine SWR-1022D subs that will be wired up with voice coilsin series, then in parallel with each other givin a total of 2ohm. What I want to know is how much power to feed them. I figure that being in parallel and 500wrms each, they will need a 1000wrms amp (Eg. Alpine MRD-M1005). However the 2 Alpine dealers I have spoken to have both said to use the 600wrms MRD-M605 amp. I always assumed that it was better to go bigger than smaller as distortion from underpowering was the main killer of speakers. So which way do I go? Also I as these are my first DVC subs, are they rated per coil or as some sort of total? Eg. 500wrms per coil, or combined? Help and opinions would be greatly appreciated.

According to the Alpine website the suggested RMS or continuous power handling of these woofers is 300 watts total. So 150 per voice coil.

Power Handling Capacity (RMS) : 300W...from the Alpine site.

So taking the suggestion of the local dealers is advisable. An amplifier producing a total of 600 watts RMS at 2 ohms is an ideal match for you. There is no need to go higher than this. You simply encounter more strain on your car's electrical system and exceed the thermal power handling capability of the subs.

Last years model is 300WRMS, this years is 500WRMS. Look here for SWR-1022D: https://www.alpine.com.au

nick_ss wrote:

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Last years model is 300WRMS, this years is 500WRMS.

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My mistake, I was looking at the s-type

Well, if you feel the need to power them to the full RMS rating (which I am a fan of) get an amp that is capable of producing 1000wrms @ 2 ohms.

nick_ss wrote:

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I always assumed that it was better to go bigger than smaller as distortion from underpowering was the main killer of speakers.

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Wrong assumption and a lingering misconception.  Overpowering kills speakers.  And idiots who turn up the gains past there limits kill speakers.  But this much is true:  you should buy enough power to make you happy, and the speakers should have enough capacity to handle the highest amount of power you throw at them.  Which means that the speakers should be rated greater than the power source.

In your opinion stevdart, which amp should I go for, the 600wrms or the 1000wrms? I know that powering speakers at their max will kill them, but I was also told that using an amp that is too small would have too work at it max, therefore creating harmful distortion. Thus it was better to choose an amp capable of powering the speakers to their max so that during normal use, the amps would not be working hard. That means if I was to use the 1000wrms amp it would most likly never be pushed over 3/4 of its potential power. On the other hand if I was to use the 600wrms amp, even at full power it would only deliver 300wrms to each speaker, and would therefore be constantly running at its max. This is what I think, if I'm wrong correct me and tell me what I should be doing.

Thankyou Alpine Guy. Out of curiosity, do the M1000 and  M1001 have high level inputs, or just low level?

Cheers,

Nick

So that means you're using the factory deck?  This is what you need to know about this kind of setup:  OEM decks were made to power OEM speakers without the aid of outboard amplification.  The only signal output they will provide is the high level speaker output which you were referring to.  High level signals are higher voltage but noisier than the low level outputs (RCA) provided on aftermarket decks.  This setup involves more precise work and a high quality converter.  So why not use the built-in high to low converter that the amp provides?  Because it's free.  It's built as a freebie and works like a freebie.  So don't use it.  Use a quality converter made by some of the better manufacturers of these types of devices.  (Search for LOC or converter for links and recommendations.)

You also stated above:  but I was also told that using an amp that is too small would have too work at it max, therefore creating harmful distortion.

That's not right.  An amplifier working at its capacity will provide clean output.  That's what capacity means...its uppermost limit.  It is when you set it to go beyond its limits that it clips the signal.  This is taken care of in the process of setting gain to match the clean output of the deck.

And you should also know this:  an OEM deck will normally go into clipping at about halfway on the volume dial.  You have to find that point and set the amp's gain to reach its highest output at that point.  You can't assume the "3/4 rule" with OEM decks.  Using the test tone procedure, you will hear clipping from the deck the same way you hear it from the amplifier (but at a quieter level because the amplifier will not be processing the signal).  This will leave you with a rather narrow range to adjust the volume, just so that you're aware.

And oh, Alpine Guy is the one you want to hear from about choices of Alpine amps!

Yes, I will be using the OEM deck (with a H->L signal converter now seeing as you state the built-in one in the amp is not the best) but the OEM deck will only be used temporarily, until I decide what HU I want and what I'm going to use for the rest of the system. (Subs are an Xmas pressie that I'm getting) What about a sub x-over? Should I use an external one or is there one built into the Alpine monos? (Alpine Guy?)

Nick