Can I power 2 sundown SA 12"a with this amp?

[kr15 5,000+ posts]

Build a big box first. I'm with using what you have first. Years ago when I smoked a Crescendo I temporarily put a treo 75.2 on an sa12 and it was still plenty loud. The treo did like 500 bridged

 

[mrpep]

Ok, I will try it - so I will tune 750 rms X 2 subs = 1500 rms X 2 ohm = 3000

square root of 3000 = 55 volts - so I will tune the alpine to the calculated spec using a DMM - how would I know if my amp is clipping ??

Sent from my iPhone using Tapatalk

 

[tymoto21 10+ year member]

It would be 1000w

You have to use the amps output not what the subs can take

1000w x 2ohm = 2000

square root of 2000 is 44

Find a -6 Db tone at around 45hz

Set bass boost all the way down

Disconnect subs from the amp

Turn the head unit to max then back it down 3 or 4 clicks

Use gain on amp to get 44vac on the output terminals

Connect subs for 2 ohm ( measure to make sure they are wired to 2 ohms)

Rock out

Or you can just connect them and turn the gain up until you can hear distortion then back it down a little bit

 

[mrpep]

This means I will under power those subs though won't it ?

Sent from my iPhone using Tapatalk

 

[kr15 5,000+ posts]

Yes the subs will be underpowered. .that's why I said to build a large box to compensate for power.

 

[Jeffdachef 5,000+ posts]

[quote name='mrpep']What reliable website has this amp ? I did call alpine to question the capabilities of the MRX-M100 and they actually told it would handle the sundowns at 750 rms each = 1500. Not sure what my next move should be ....


Sent from my iPhone using Tapatalk[/QUOTE]

@SounDrive is a dealer for FSD. I'd take that over the alpine anyday if you want things to get crazy. Or look for an alpine mrp 2000 or mrx240 if you are dead set in running 2 ohms.

 

[mrpep]

[quote name='Jeffdachef']@SounDrive is a dealer for FSD. I'd take that over the alpine anyday if you want things to get crazy. Or look for an alpine mrp 2000 or mrx240 if you are dead set in running 2 ohms.[/QUOTE]

Can the SA's run at 1 ohm ? If not , I will have to use 2 ohms which will give me 950 watts on that FSD and for that I might as well stay with the alpine since the alpine gives me 1000 at 2 ohms.


Sent from my iPhone using Tapatalk

 

[mrpep]

Come to think of it , I will set my gain on my home amp to 44 volts and see what it will sound like. If these baby's bang hard then I could probably safely assume that a good box and that alpine might give me what I need or close to it. Jeff, I am seriously considering that amp by the way , I would like to get what I can out of these subs.

Sent from my iPhone using Tapatalk

 

[Massive spl]

Come to think of it , I will set my gain on my home amp to 44 volts and see what it will sound like. If these baby's bang hard then I could probably safely assume that a good box and that alpine might give me what I need or close to it. Jeff, I am seriously considering that amp by the way , I would like to get what I can out of these subs.

Sent from my iPhone using Tapatalk

What home amp do you have? How many watts is it?

 

[mrpep]

I have a peavy 2000 - it will load 2000 watts bridged

Sent from my iPhone using Tapatalk

 

[Massive spl]

I have a peavy 2000 - it will load 2000 watts bridged

Sent from my iPhone using Tapatalk

They should hammer but remember your in a huge room in a house prly... Not in a car.... Run wires from house out to your car and see if they slam inside your car

 

[Jeffdachef 5,000+ posts]

Can the SA's run at 1 ohm ? If not , I will have to use 2 ohms which will give me 950 watts on that FSD and for that I might as well stay with the alpine since the alpine gives me 1000 at 2 ohms.

Sent from my iPhone using Tapatalk

IF you have two dual 2 ohm subs, you can only wire 2 ohms or half ohm.... Two dual 4 ohm subs will give you 1 ohm or 4 ohm wiring. This is basic man... The FSD will do way more power at half ohm. More than 1600+ watts total after box rise. Your alpine does jack sh*t in comparison, will probably do less than 500 after box rise.

 

[mrpep]

These SA's are 1 ohm each according to my DMM. But when I bring powers and grounds together I believe it drops to 1 ohms , does this theory sound accurate ?

Sent from my iPhone using Tapatalk

 

---------- Post added at 03:22 PM ---------- Previous post was at 03:22 PM ----------

 

These SA's are 1 ohm each according to my DMM. But when I bring powers and grounds together I believe it drops to 1 ohms , does this theory sound accurate ?

Sent from my iPhone using Tapatalk

Sent from my iPhone using Tapatalk

 

[Jeffdachef 5,000+ posts]

These SA's are 1 ohm each according to my DMM. But when I bring powers and grounds together I believe it drops to 1 ohms , does this theory sound accurate ?

Sent from my iPhone using Tapatalk

 

---------- Post added at 03:22 PM ---------- Previous post was at 03:22 PM ----------

 

Sent from my iPhone using Tapatalk

no you are measuring them wrong. They dont make them in dual 1 ohm. You dont wire anything up and you put the multi meter on each coil(speaker terminal side). If you wire it up together you are measuring it wrong.

 

[mrpep]

They should hammer but remember your in a huge room in a house prly... Not in a car.... Run wires from house out to your car and see if they slam inside your car

For that I might as well just use the car amp, lol - I get your your point though.

Sent from my iPhone using Tapatalk