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Polk Audio MM840 8" Sub - Where?

PostPosted: Tue Dec 04, 2012 7:39 pm
by Prezza
Hey,

As it seems the MM840 is a very popular rear parcel shelf sub upgrade, i have decided to go for one.

My car was bought with an aftermarket amp, and 12" boxed sub in the boot, and while the bass is awesome when needed, it takes up far too much room. Also, the clown screwed the amp into the carpet so it didnt move around. Catch is, i cant remove the carpet, or access the spare tyre/tools.

My plan is to mount the amp on the rear of the back seat in the boot, and have the wires simply run up and power the MM840. Ill also dynamat the shelf to reduce rattles.

Now, the big question, is where is the best/cheapest place to buy these subs?

The cheapest place i can find, that readily ships to Aus, is this seller on ebay. Comes to around $160 delivered.
http://www.ebay.com.au/itm/321027284570 ... 1423.l2649

Does any one else know of any where cheaper?

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 6:02 am
by bigBADbenny
Mickyboy bought one of these or similar recently...
I believe these can use the factory amp? :-)
Installing a port or vent in the rear parcel shelf provides a little more punch (DIY on LGT)...

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 9:17 am
by Fourlex
bigBADbenny wrote:Mickyboy bought one of these or similar recently...
I believe these can use the factory amp? :-)
Installing a port or vent in the rear parcel shelf provides a little more punch (DIY on LGT)...


what would be an ideal solution for this? i'm in a similar pickle.. because i'm worried the subs in the back won't be as nice sounding due to... being in the boot with not much ventilation, and putting down the middle man hole seat might do some justice.. ah the dilemma.

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 9:34 am
by Mickyboy
I got mine from Performance Car Audio in Bayswater. $170 from memory.

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 9:45 am
by bigBADbenny

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 11:15 am
by shav
Mickyboy wrote:I got mine from Performance Car Audio in Bayswater. $170 from memory.

did you go pick that up yourself from them Mick or was that delivered?

Also what is the difference between the SVC and DVC subs in the Polk range?

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 11:32 am
by Mickyboy
Yep picked it up. Friendly guys there. You need the SVC (single voice coil) model.

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 1:50 pm
by SegR
bigBADbenny wrote:Rear deck vent mod: http://tinyurl.com/cbv94l5
Polk DB: http://tinyurl.com/cl63ads
Polk MM: http://tinyurl.com/ce9dutz


That's a great vent mod. When I get a sub in my boot, it looks like removing the mac sub on the rear shelf will be the way to go.

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 3:08 pm
by bigBADbenny
I had thought they were running the stocker or an 8" upgrade in the stock location, plus adding a flush vent? :D

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 3:36 pm
by shav
Mickyboy wrote:Yep picked it up. Friendly guys there. You need the SVC (single voice coil) model.

so could I run a Dual voice coil if I have a better amp?

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 4:00 pm
by garbo41610
shav wrote:
Mickyboy wrote:Yep picked it up. Friendly guys there. You need the SVC (single voice coil) model.

so could I run a Dual voice coil if I have a better amp?


A DVC provides more flexible wiring configurations.

Depending on your amp, if it's a monochannel amp stable at 2ohm (which it probably is without knowing the specs) you can use;
a SVC 4ohm driver to present a 4ohm load to the amp
Image

or

a DVC 2ohm driver to present a 4ohm load to the amp
Image

or

a DVC 4ohm driver to present a 2ohm load to the amp
Image

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 4:02 pm
by bigBADbenny
Genius!
So is SVC or DVC better for for the factory amp?

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 4:03 pm
by shav
thanks garbo.

Can u explain to me what kind of SQ I would get from a DVC over and SVC?

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 4:19 pm
by garbo41610
shav wrote:thanks garbo.

Can u explain to me what kind of SQ I would get from a DVC over and SVC?


Absotively posolutely no difference all things being equal. i.e. comparing a SVC 4ohm driver to a DVC 2ohm driver presenting a 4ohm load

Re: Polk Audio MM840 8" Sub - Where?

PostPosted: Wed Dec 05, 2012 4:36 pm
by bigBADbenny
Awesome! Thanks for clarifying that! :D