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Gnomez
03-19-2005, 11:51 PM
i have 2 polk mm124's with jvc CS-HX6945, and a jvc KS-AX7700 amp. Thanks.
MacLeod
03-20-2005, 01:43 AM
Those subs need 400-500 watts RMS to make em work right. How much does that amp push?
neomagus00
03-20-2005, 05:28 AM
note: RMS values, not peak.
Gnomez
03-20-2005, 01:45 PM
it pushes 900 watts but it can be bridged
MacLeod
03-20-2005, 07:03 PM
Is that 900 peak?

Is it a mono amp running 900 RMS at 2 ohms mono?

I didnt think JVC made a 900 mono amp.
neomagus00
03-20-2005, 07:21 PM
yes, i looked it up, and that is peak.

gnomez: i assume you're running those 4-ways off of the headunit. that amp isn't nearly powerful enough to drive those subs. it makes 150 W x 2 Ch. @ 4 Ohms. Even if you assume it has vast headroom and is 2-ohm stable in its standard configuration, that's only 600 W x 1 Ch. @ 4 Ohms. Those subs want 500 apiece, and they'd be getting about 150 each at most, any way you wire it. a new amp is definately in order, if possible. if you're already set up, it'll work, but not close to full potential.

2 useful notes: this (http://www.andrew.cmu.edu/user/dhuston/audioindex.html) is how to set the gains for your amp, and those subs need to be broken in very slowly.
MacLeod
03-20-2005, 07:24 PM
Well I guess my lazy ass couldve looked up the amp but....Im lazy! :p

If that amp is putting out 150x2 then its WAY underpowering those subs.

The good news is youre in no danger of hurting your subs cause even in clipping it will never send out enough watts to hurt those subs.

The bad news is that it will never send out enough watts to make those subs sound as good as they can either.
Gnomez
03-21-2005, 08:25 PM
what about the polk c300.2?
MacLeod
03-21-2005, 09:38 PM
Not enough grunt for 2 2124's. The C500.1 would be a much better choice. It puts out a little over 600 watts and that would be 300 to each 2124 and that would be just fine.
Gnomez
03-22-2005, 08:46 PM
ii dont have the 2124's i have the mm124's so will the c500.1 still do er?
MacLeod
03-22-2005, 09:56 PM
Oops, my bad.

The MM124's handle 500 watts so the 300.2 would definitley be too small.

The 500.1 would be ok for them. It would be 300 per sub which could be a little low but we heard a lot of complaints of the MM124's blowing when powered with 500 watts so actually the 500.1 may not be a bad choice.
neomagus00
03-22-2005, 10:15 PM
well, as we know, amps are often underrated, so a '500 W' amp could easily push 600 W, which WILL blow a sub, if it's accurately rated at 500 W. Just a thought.

Although, I don't know how you can blow a sub... wouldn't the awful distortion warn you something's up before the coil actually burns?
MacLeod
03-22-2005, 10:58 PM
The 500.1 IS very underrated. It put out over 600 watts in a Carsound test. That would be 300 to each MM124 which are 500 watt subs and so it would be a little on the low side.

How can you blow subs? Ask Cody.....6 times! :p
exalted512
03-23-2005, 12:14 AM
play nice;)
i think i have number 7 and 8 sold for $215 shipped.
hopefully...
considering each sub was $270 + $20 for each grill im getting royally screwed. but since polk cut the price to $200 with the box and the grill i didnt do too bad...
-Cody
Gnomez
03-23-2005, 01:01 AM
so the c500.1 will do the job? and can i bridge it so i can get more power out of it?
MacLeod
03-23-2005, 07:10 PM
Its a mono amp which means it only has one channel which means you cant bridge it. Youd get a half channel.

If you hook up a single 4 ohm voice coil, youll get a 4 ohms load. If you hook up 2 4 ohms voice coilc youll get a 2 ohm load and the most power.
Gnomez
04-03-2005, 07:18 PM
i think im going to go for the rockford fosgate T10001bd amp. will that be enough power?
MacLeod
04-03-2005, 09:25 PM
That will be plenty of power. The new Power amps by RF are F'ing badass amps.
Gnomez
04-08-2005, 08:21 PM
would the kenwood kac8101d amp work for 2 mm124's?
MacLeod
04-08-2005, 11:20 PM
If its an 800 watt amp thatll run 400x2 at 2 ohms then yes it would.
Joelsbass
04-10-2005, 04:45 AM
I can't help but wonder... and maybe Thom, Kim, or Josh can help out on this, but are the subs blowing more from thermal overload or are they bottoming out?
MacLeod
04-10-2005, 01:05 PM
I would guess over extension. Havent most of the complaints been of the leads coming off and such? These arent SPL subs and dont have a great deal of excursion, so if this would be my guess.
audiobliss
04-12-2005, 12:06 AM
Originally posted by Joelsbass
I can't help but wonder... and maybe Thom, Kim, or Josh can help out on this, but are the subs blowing more from thermal overload or are they bottoming out?

I would also like to know this for a fact.