Have a few questions

[06Titan 10+ year member]

I am looking to buy a new amp, and some subs, but have a few concerns...

I have been looking at a MMATs D3500.1 - and was wondering what it means when its rated at resistive and sine-wave power? Is it good/bad that it only has two adjustments that the user can make? Any informtion on this amp would be great, because I haven't found too much info searching this forum...

Is it better to strap 2 amps to make 3K RMS, or have one big amp produce it? I had 2 Audiopipe 1500ds strap, and it seemed to push my subs pretty good, but have been a little disappointed when I put a big 3K amp alone. Is it just me?

Also, I have about 3.8 cu ft gross, what would you recommend? Porting 2 12s, or sticking with my 5 8" SS Orphans?

Sorry if these are general questions, but haven't been able to find answers searching the forums. Any help is appreciated!

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[BnGRacing 10+ year member]

I have been looking at a MMATs D3500.1 - and was wondering what it means when its rated at resistive and sine-wave power? Is it good/bad that it only has two adjustments that the user can make?

The power rating means that a resistor, not a speaker, was used to determine max power ratings. Sine-wave power is your max power when the amp is at the proverbial "pedal to the metal". Music power was back when IHF-200 ratings were prevalent and you'd see a rating of "+1.2dB of dynamic headroom". It's all basically marketing speak and I wouldn't worry about it much.

Is it better to strap 2 amps to make 3k than use 1 amp?

Why the hell do you want 3kW for a couple subs? When buying amps, you start to run into diminishing returns rather quickly and my God does 3kW take a lot of current. You're probably running at 1ohm, or below, and lowering the efficiency of the amp (as well as its lifespan) and ******* up 350+ amps of current doing so. Unless you have some big alternators and a couple extra batteries...don't you think it would make more sense to buy more efficient subs so you can get just as loud with 1/3 the power?

I don't have any experience with MMATS, so I can't tell you if it's a good amp or not. What I can say is that 3kW is a stupid amount of power and you'll spend a lot of money on your car's electrical just so you don't suffocate the power supply. And after all that time & money, you probably wouldn't notice a difference if you went down to a 1kW amp. When you double the power, you double 'paper' SPL and not real SPL. Same thing, maybe even worse, happens when you halve the impedance.

Something to think about before your next purchase.

 

[06Titan 10+ year member]

The power rating means that a resistor, not a speaker, was used to determine max power ratings. Sine-wave power is your max power when the amp is at the proverbial "pedal to the metal". Music power was back when IHF-200 ratings were prevalent and you'd see a rating of "+1.2dB of dynamic headroom". It's all basically marketing speak and I wouldn't worry about it much.
Is it better to strap 2 amps to make 3k than use 1 amp?

Why the hell do you want 3kW for a couple subs? When buying amps, you start to run into diminishing returns rather quickly and my God does 3kW take a lot of current. You're probably running at 1ohm, or below, and lowering the efficiency of the amp (as well as its lifespan) and ******* up 350+ amps of current doing so. Unless you have some big alternators and a couple extra batteries...don't you think it would make more sense to buy more efficient subs so you can get just as loud with 1/3 the power?

I don't have any experience with MMATS, so I can't tell you if it's a good amp or not. What I can say is that 3kW is a stupid amount of power and you'll spend a lot of money on your car's electrical just so you don't suffocate the power supply. And after all that time & money, you probably wouldn't notice a difference if you went down to a 1kW amp. When you double the power, you double 'paper' SPL and not real SPL. Same thing, maybe even worse, happens when you halve the impedance.

Something to think about before your next purchase.

Thanks for your input. This is why I decided to start a thread asking questions before I spend a bunch more money.

This leads me to more questions though: How does lowering power net me similar SPL results rather me sticking with 3KRMS? Is there an article that could perhaps explain this to me?

My reasoning for a bigger amp was if i used a bigger amp to power the subs, it would need to work less, rather where I would push a smaller amp to get the same results with the bigger amp working less

Here is my current set up:

Kenwood DDX814

Big 3

KK Colossus 0 Guage

Oddyssey PC1700 Main Battery

XS Power D925 secondary battery

Max box size will be about 3.8 cu ft GROSS!

As for subs, I am undecided because I am unsure of what amp to get. I currently have 5 SS 8" Orphans...

Keep in mind, the enclosure/subs are going underneath the back seat of my 2006 4 door Nissan Titan

 

[TheUnderFighter 10+ year member]

From what I've heard from a LOT of people MMats are GREAT amps, and not enough praise can be sung by them. They are very very efficient and typically underrated as well. It'd be a great upgrade from the 2 strapped APs.

As for lowering power to attain similar results, I think he means the difference from 3kw and 2kw in terms of SPL, may not be that great, being only a handful of decibels that you're not really gonna hear the difference on.

However, five 8s is a pretty cool set-up to say you have, is it ported? And finding two 12's in that power range, in that small of an enclosure is gonna be tough, but I bet you could fit a pair of 10's in there.

 

[06Titan 10+ year member]

From what I've heard from a LOT of people MMats are GREAT amps, and not enough praise can be sung by them. They are very very efficient and typically underrated as well. It'd be a great upgrade from the 2 strapped APs. As for lowering power to attain similar results, I think he means the difference from 3kw and 2kw in terms of SPL, may not be that great, being only a handful of decibels that you're not really gonna hear the difference on.

However, five 8s is a pretty cool set-up to say you have, is it ported? And finding two 12's in that power range, in that small of an enclosure is gonna be tough, but I bet you could fit a pair of 10's in there.

Im not just looking at the MMATs amp, I was also thinking of the T2500. My bro bas one I can toss in the truck and play around with.

My previous set up I had 2 different sets of 10s ported that hit 137.9 @ 36 HZ sealed and 139.7 with my windows down. The current set up with the 8s is ported and gets tons lower (which is what I ultimately want) and seems louder all the way around. I haven't metered this set up yet. Numbers aren't my #1windows priority, but I would like to be able to say I can hit a 142 without tuning real high. Compared to my last set up, I think im almost there.

Maybe I will need to add another XS Battery. What's "good" electrical for 3KRMS?

 

[TheUnderFighter 10+ year member]

The same thing can be said about those Rockfords. Much too expensive to buy new, but you know you're getting quality, and they come with a birthsheet that I would be surprised to hear is rated for over 3kw.

And I'd keep your 8's then for sure bro. I think it's a very cool set-up, and it gets low just like you want. Two 12's would be very limited on space in there.

What's your current electrical? I wouldn't be able to say for sure, but a HO Alt, and prolly 2 bats in the trunk at least, with duals runs of 1/0

 

[audioholic 5,000+ posts]

...don't you think it would make more sense to buy more efficient subs so you can get just as loud with 1/3 the power?

While I dont know if its completely necessary in the OP's case, Hoffman's Iron Law tells us that more efficient subs are not the end-all advantage you are suggesting they are. In some situations, its preferable to run less efficient drivers.

HIL: high efficiency, small enclosure, low frequency extension... pick two.

 

[06Titan 10+ year member]

How do I know how efficient certain drivers are?

These are the current ones I am using - SSA Shop - SoundSplinter Orphan 8" sub woofer

Box is a bit small as of now, but will be using a box that's around 3 cu ft net...

 

[BnGRacing 10+ year member]

While I dont know if its completely necessary in the OP's case, Hoffman's Iron Law tells us that more efficient subs are not the end-all advantage you are suggesting they are. In some situations, its preferable to run less efficient drivers.
HIL: high efficiency, small enclosure, low frequency extension... pick two.

The difference is his subs have an efficiency rating of 78dB...that's pretty inefficient and is a reason why one would throw more power at them. A larger woofer will be more efficient, actually...pretty much anything would be more efficient than that. With that, it's not unreasonable to expect maintaining the same perceivable output while using 1/3 the power. Most higher end subwoofers are made to be used in small enclosures and have low frequency extension. It's rare to come across a subwoofer for 12v applications that has an efficiency rating >100dB 1w 1m. But finding something in the middle? That should be easy.

There's a lot of ways to skin this cat, I'd consider throwing more power at woofers to be way down on the list of things to try. People forget how loud some systems can get with 500w. If people choose equipment based on what would work the best in their vehicle instead of being concerned with using the right brand, this industry would be in a different place. That'll never happen b/c too many people think a subwoofer rated at 1500w will be 3x as loud as one rated at 500w.

 

[audioholic 5,000+ posts]

The difference is his subs have an efficiency rating of 78dB...that's pretty inefficient and is a reason why one would throw more power at them. A larger woofer will be more efficient, actually...pretty much anything would be more efficient than that. With that, it's not unreasonable to expect maintaining the same perceivable output while using 1/3 the power. Most higher end subwoofers are made to be used in small enclosures and have low frequency extension. It's rare to come across a subwoofer for 12v applications that has an efficiency rating >100dB 1w 1m. But finding something in the middle? That should be easy.
There's a lot of ways to skin this cat, I'd consider throwing more power at woofers to be way down on the list of things to try. People forget how loud some systems can get with 500w. If people choose equipment based on what would work the best in their vehicle instead of being concerned with using the right brand, this industry would be in a different place. That'll never happen b/c too many people think a subwoofer rated at 1500w will be 3x as loud as one rated at 500w.

Be careful about placing too much reliance on subwoofer efficiency specs. They are rated at 1khz, which the sub will realistically never come close to reproducing. While subs generally dont make dramatic efficiency changes from their usable range (20hz-120hz or so) and that 1khz, it is note worthy to say that a 1,000hz efficiency measurement is not always reliable.

Cutting power by 2/3 while maintaining the same output levels means you will undoubtedly either need a sub that requires a larger enclosure, or one whose low frequency extension is inferior. Its absolutely true that a 1500 watt sub is not automatically 3x as loud as a 500 watt sub, but with that large of a swing in power, something has to give, and HIL will dictate what that compromise is going to be.

3x as loud isn't exactly an accurate description of what you meant. Doubling of power, all other factors being equal and ignoring things like power compression and impedance rise, will net a gain of 3db. Tripling it would net approx 4-1/2 decibels. Again, roughly speaking and ignoring real world factors that will decrease that gain. So like I said, talking about '3x as loud' is only going to give less knowledgeable people here a misconception about power versus output potential. Some people mistakenly consider a 3db increase as 'twice as loud', simply because that's the theoretical gain from doubling your power (or cone area), but most studies indicate that a perception of 'twice as loud' requires anywhere from a 6 to 10 decibel increase. Things are further complicated because its impossible to say exactly what 'twice as loud' really is, because its like asking someone what 'twice as blue' is. Not saying this to be argumentative, just clarifying for accuracy.

Lastly, I completely agree with you that when someone asks how to increase the output of their system substantially, throwing more wattage at it is generally one of my last suggestions. Again, power compression and imp rise will mean they will be fighting an up hill battle, while other choices like a different enclosure design (size/type/alignment) or changing woofers usually has a greater potential for more output increases.

 

[06Titan 10+ year member]

Got a lot of good information going on in here! Thanks!

I think for now I am going to focus on my enclosure and a better amp. I will stick with the 5 Orphans (mainly due to funds), and pick up a better amp and build a bigger/better enclosure. I should be gaining about 1 cu ft net which should help the system with output. Is there a guide or anything to help choosing an amplifier? All those specs listed mean something...

 

[TheUnderFighter 10+ year member]

Well I think either amps you were looking at are both good buys. Did you have a good deal on them or did you just throw those out there? And what ohm do you need your power made at?

 

[06Titan 10+ year member]

Well I think either amps you were looking at are both good buys. Did you have a good deal on them or did you just throw those out there? And what ohm do you need your power made at?

Those were just some amps I was looking at. My subs wire down to 1.0 ohms before box rise...

 

[hispls 5,000+ posts]

Those subs are great, you'd be hard pressed to beat that setup as far as power handling and flexibility of box design for limited space.

I think you'd be happy with either the MMats or the Fosgate, both are quality pieces and should deliver similar power (I hear the Rockford 2500 does a good bit over 3KW).

One amp is better than 2 strapped generally except if you start getting bigger than about 3KW there's very few that are reliable.

I would worry that you don't have the electrical to back up a 3K amp though. Either another battery or a HO alternator is probably in your future depending on your listening habits.

 

[06Titan 10+ year member]

Those subs are great, you'd be hard pressed to beat that setup as far as power handling and flexibility of box design for limited space.
I think you'd be happy with either the MMats or the Fosgate, both are quality pieces and should deliver similar power (I hear the Rockford 2500 does a good bit over 3KW).

One amp is better than 2 strapped generally except if you start getting bigger than about 3KW there's very few that are reliable.

I would worry that you don't have the electrical to back up a 3K amp though. Either another battery or a HO alternator is probably in your future depending on your listening habits.

Thanks for the encouraging words, glad to hear I am in the step in the right direction. I plan on adding another battery, just not sure when. I need to find a spot to place it first, lol.