I'd like to see if anyone has any opinions on Polk Audio's MM840dvc subwoofer. They are relativly inexpensive at $80-$120 each, and from what I've been reasearching may be a great 8" subwoofer for a mid-powered system.
The amp I'll run to push these guys is an old-school Gen X Hifonics Thor, rated for 125w per channel at 4 ohms. Wired corectly, this amp should provide conservativly clean power of ~200wRMS, with loading the amplifier down to 2 ohms per channel (DVC 4ohm coils wired in parallel).
The car I'll personally be driving and playing these in is a Nissan 370z, which is a two seater sports-car with minimal trunk space. I'll be installing these subs in place of the spare tire and under-carpet tools. I'm currently running a single Pioneer pre-IB-Flat 10" woofer which sounds decent, but have been told to try 8" woofers for maximum 'impact' punch from my electronica likeness. The pioneer 10" currently sits inside of my factory spare tire.
Has anyone heard, played, or installed Polk Audio mm840 / mm840dvc subs?
Polk'd website:
Polk Audio - Mobile Monitor Series - Mobile / Marine Speakers
The amp I'll run to push these guys is an old-school Gen X Hifonics Thor, rated for 125w per channel at 4 ohms. Wired corectly, this amp should provide conservativly clean power of ~200wRMS, with loading the amplifier down to 2 ohms per channel (DVC 4ohm coils wired in parallel).
The car I'll personally be driving and playing these in is a Nissan 370z, which is a two seater sports-car with minimal trunk space. I'll be installing these subs in place of the spare tire and under-carpet tools. I'm currently running a single Pioneer pre-IB-Flat 10" woofer which sounds decent, but have been told to try 8" woofers for maximum 'impact' punch from my electronica likeness. The pioneer 10" currently sits inside of my factory spare tire.
Has anyone heard, played, or installed Polk Audio mm840 / mm840dvc subs?
An externally hosted image should be here but it was not working when we last tested it.
Polk'd website:
Polk Audio - Mobile Monitor Series - Mobile / Marine Speakers
I've seen those little sundown subs myself. I think they are more for ported enclosures with 80db 1w/1m and like you said; maximum SPL. There are a few problems with me running that sub, and believe me I looked at the sundowns, the JLw7, and dd1508. With the exception of the JL, the other two are more for bass hungry folks and dds only recommended for ported boxes. I'm looking for more sql which I know the JL would give but I cannot fit it in my car nor cover the premium cost for 1~2 of them.
1. 80db 1w/1m for that sundown would mean it would probably want a ported box to raise efficiency which is a buzz-kill for my install complexity and fondness of sealed box sound. Also, my amp although powerfull will not be able to drive more than just one of these subs but it could provide 4~500w if needed.
2. Those cost 2x as much. Granted they are probably 4x more powerful than the polks so maybe this isnt so bad off. I'd be able to buy just one of them.
How good do they sound in a sealed box?
1. 80db 1w/1m for that sundown would mean it would probably want a ported box to raise efficiency which is a buzz-kill for my install complexity and fondness of sealed box sound. Also, my amp although powerfull will not be able to drive more than just one of these subs but it could provide 4~500w if needed.
2. Those cost 2x as much. Granted they are probably 4x more powerful than the polks so maybe this isnt so bad off. I'd be able to buy just one of them.
How good do they sound in a sealed box?
I know this may not be the most helpful, but I ran a single MM1040 for a while in about .65 cu.ft. sealed while I was refoaming the surround on my JL 10W6v1. Once I was done re-foaming the JL, I didn't put it back and kept running the Polk. I have since moved on and so has the vehicle, but I still think about that Polk. The vehicle was a Ford Expedition with the stealthbox installed in the side compartment.
Probably not as well, I see your more like me where SQL matters more. Then for the price range and rms handling the mm's would probably fit your liking then. I haven't heard them so I cannot comment. It's been a long time since I could find a good sealed type sub like the IDQ max's
Just wondering if you pulled the trigger on the Polk's.
I did on one JBL GTO-804 and just finished the .6 cu.ft. vented enclosure. Very impressive little driver for $58. I must agree with all of the positive reviews around the WEB about it. So, if you haven't bought the Polk's yet you may want to give these a shot.
I did on one JBL GTO-804 and just finished the .6 cu.ft. vented enclosure. Very impressive little driver for $58. I must agree with all of the positive reviews around the WEB about it. So, if you haven't bought the Polk's yet you may want to give these a shot.
I'm currently using a pair of those (since Jan 2011) in a common chamber ported box feeding about 800watts to the pair. produces a fair amount of low end with really nice SQ easy to blend with the Focal front stage.
My Noisy Ride
My Noisy Ride
Sounds good to me. I hope they are sharp like an 8" with the bass like a 10".
Someone told me to try a hybrid box, with ~.5cu sealed for one sub, and then ~1cu ported for the second sub. They said this would fill out the frequency range from top to bottom while not compromising the effectiveness or causing any deficiency. I have the chance to do this since I am designing the box this week. Thoughts?
Someone told me to try a hybrid box, with ~.5cu sealed for one sub, and then ~1cu ported for the second sub. They said this would fill out the frequency range from top to bottom while not compromising the effectiveness or causing any deficiency. I have the chance to do this since I am designing the box this week. Thoughts?
I probably wouldn't do that, but then I have never thought about doing it either so I can't comment on how that will work out.
For me, it seems like it would complicate the filter settings, both low pass and the subsonic. I like simple so I would choose either vented OR sealed. So if you have the means I would build one of each and decide which is best or choose the one that fits.
Of course I could have this all wrong, so I'll keep tuned to see somebody comment with experience doing exactly that setup.
For me, it seems like it would complicate the filter settings, both low pass and the subsonic. I like simple so I would choose either vented OR sealed. So if you have the means I would build one of each and decide which is best or choose the one that fits.
Of course I could have this all wrong, so I'll keep tuned to see somebody comment with experience doing exactly that setup.
Mine does lows pretty good. moves a lot of air for two 8's, you could feel it from the front seats. not as much car wrecking bass as my previous DD 1508's but more controlled and doesn't stand out from the fronts so they blend in much more easily.
I wouldn't do the different box thing too unless you know exactly what you're doing or don't mind wasting time and wood incase it doesn't work as planned.
I wouldn't do the different box thing too unless you know exactly what you're doing or don't mind wasting time and wood incase it doesn't work as planned.
I finally got these little subs hooked up to 400w each of an old Soundstream Reference 1000sx: http://www.diyaudio.com/forums/car-audio/193012-soundstream-reference-1000sx.html
These little subs sound amazing in the home-built boxs I crafted. Due to my trunk space, I had to make 2 equally sized boxes. I went with sealed boxes to keep the size small and was able to make the boxes 0.5 cubic feet each.
The sound from these subs is mellow and clean, They punch very hard and have have way more than enough low end for most needs. For the price I paid these subs sound like much better speakers. I'm surprised this line of Polk subs are so inexpensive so if anyone is looking for 8" subwoofers the Polks are just about the best SQ sub you can buy for the money. Of course the JL Audio 8w7 is better at almost 3x the price though.
These little subs sound amazing in the home-built boxs I crafted. Due to my trunk space, I had to make 2 equally sized boxes. I went with sealed boxes to keep the size small and was able to make the boxes 0.5 cubic feet each.
The sound from these subs is mellow and clean, They punch very hard and have have way more than enough low end for most needs. For the price I paid these subs sound like much better speakers. I'm surprised this line of Polk subs are so inexpensive so if anyone is looking for 8" subwoofers the Polks are just about the best SQ sub you can buy for the money. Of course the JL Audio 8w7 is better at almost 3x the price though.
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I was lucky enough to score a dilapidated one from someone I knew and only had to pay for repair so I got a brand new 8W7 for only $150.
Anyways, these are BIG little subs, very beefy. They hit nice and clean, very responsive. With an ample amount of power, they will hit the lows with authority too!
What will you be making the enclosure out of? If memory serves me correctly those are designed for light weight applications, i.e. marine. Will you be doing a fleese/roesin or a 1/2" box with a thin layer of roesin to seal it up? Looking forward to the results either way!
I put the boxes together about 2 weeks ago. Due to my setup, I found it easiest to make two sealed rectangular boxes out of 3/4" MDF. The boxes have an internal CU of .5, which is a tad larger than recommended but is working extremely well. The boxes are sitting inside of where the spare tire goes, and just above them is 1/2" MDF laid on top which made a great new subfloor. The woofers are allowed to extend almost 3/4" upward before touching their grill, which is flat-mounted to the top of the 1/2" MDF and strong enough to stand directly on top of the woofers. I'll take some pics if you are interested
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