pcmw

Lvangundy,

There is the problem. You are power starving those woofers. You may want to spend $150 and get a good amp for those woofers. They will probably come to life and cure the issues. Other than the space issue of course.

Todd has some closeout models around his shop once in a while.

MW

TimDimman

Can you tell what speakers those are? How do you know this?

I'd hope with a surround that large, that they could handle more than 35w though

Tim

pcmw

Tim?????????????????

What are you asking?

MW

TimDimman

You made the assumption (actually probably an educated guess) that he was power starving those subs...since we have no specs on those subs, I didn't understand how you could make that assumption.

They could have a horrible motor structure, very low moving mass, and a very loose suspension, which would make 35 watts to them make them sound like a really nice mid bass...

But, with a surround that large, they don't look as if they were made to be 35watt midbasses...

Wasn't really asking a question. Just pointing out that even though 35 watts is small in the sub domain, they could be fine with it.

In all reality, however, I can't understand how any real sub output is to be expected with only 35 watts of power to each sub (unless they are 2 ohm subs).

Tim

pcmw

Tim,

I have never seen 15" woofers run off 35watts correctly. If you have, please send me a how-to. If I could get clean bass reproduction from 35w and a 15" woofer then i would have no need for the 100s of extra watts I shoved into my car.

You said it yourself,
So please do not imply that I assume because that is just an ASSumption.

MW

TimDimman

I did say assumption, but that it was more of an educated guess. Just because you've never seen a highly efficient 15" doesn't mean there isn't a sub out there that thrives with only 35 watts of power (or that there's one that can't even handle that much power).

He never stated anything about the woofers, so to say that 35 watts is power starving them, just because you've never seen one that works with 35 watts, is making an assumption (in this instance, more like an educated guess).

I'm not trying knock you here. I'm just saying you can't say that for sure. Just trying to cover the bases. Don't worry about it so much.

Tim

TimDimman

Oh, and by the way, you probably really do have no need for the 100's of extra watts you shoved into your car.



Tim

TheL

he said on his like first reply they are rated at 300w. I'm just a newbie at stereo and sound and could be way off of what you guys are talking about

DoubleWhoosh

Power ratings are somewhat meaningless, there are too many variables involved to even get into here, but basically you need as much power as you can afford. You really should spend a good bulk of your money on your amplification over anything else in the system.

For all intents and purposes, a normal person is NOT going to launch the cone due to overpowering. Of course it takes a little bit of common sense at the volume **** too! Most damage is caused by underpowering a speaker, as this is when an amp will clip, send a square wave to the speaker, then kaput.

Todd Matsubara
TM Engineering LLC
www.tmengineering.net

TimDimman

Completely agree here.

Swap meet speaks are almost always rediculously rated (1000 watts) when a good 25 watts is enough to blow them...

Clipping the amp could send an enormous amount of power to the sub (could!!!) asking for a lot of trouble.

Tim

BabaBooey

Ridiculous. Just because a speaker is being underpowered doesn't mean the amp is going to be clipped. By your logic, clipping a 50 watt amp hooked up to a DD 9515 will damage the sub. Not a chance in the world. Clipping causes damage when speakers and amp are matched appropriately and the amp is clipped. Improper VC cooling and overexcursion can cause damage to the speakers.

fierce gs

umm...i thought reversing the polarity did not dictate whether the cone actually physically goes inwards or outwards and that this was some myth...
anyone?

DoubleWhoosh

Ridiculous? I believe your statements are the ones that would be considered ridiculous.

If a speaker is underpowered, it will be clipping the amp like 90% of the time if the person doesn't know any better on how to control the volume ****! That is what can and will damage a speaker.

First of all, an amp will clip after it reaches maximum power, it could do this at a very low level, depending upon what software is being reproduced, as sound is usually a constantly changing, dynamic signal. Amps clip sooner than you think, but only for milliseconds at a time. This is many times what makes certain amps sound "different" than others. The louder you make it, the more percentage of the time it is distorting/clipping.

Next, for the most part, as long as there is a somewhat reasonable load on the outputs (anything from 2-10 ohms, say), the amp's clipping/max level is controlled by the INPUT and also is a function of the input sensitivity level. The speakers are almost irrelevant at this point.

Improper VC cooling?!??! What do you do? Put a fan on your speaker?!?! Get a clue man, it's super high voltage or square waves that cause them to get unreasonably hot. Once again, most people won't have super high voltage going to their speakers.

Overexcursion? I don't think you have seen or been in the presence of true overexcursion. It is pretty scary, and only an idiot would do this. This goes RIGHT back to what I said earlier, for regular people/systems out there, they will NOT be able to do this. I highly doubt they will have an amp that can do this, they will most likely clip their signal first.

A speaker that is receiving a properly crossed over, nondistorted signal will be able to play hundreds of watts safely for a long period of time.

(We are talking about subwoofers here in general).

Example, I built a car with 3 10's in it, each was powered by an amp that put out about 900 watts. The tweeters were powered by 600, and the mids were powered by another 600. This system could play ALL DAY LONG at high volume like this. These were not some overrated cheesy amps either, they were some pretty big zapco units.

This car drove around the country, abused by who knows who, completely unsupervised, and 50,000 miles and two years later, not one speaker was blown. This is a pretty amazing feat for any stereo system, and is proof of exactly what I am talking about.

Please don't come in here and post information that is not true, as you will confuse the already confused people. They are obviously asking for help for a reason, and you are leading them in the wrong direction. This type of misinformation is what makes message boards such as these quite dangerous.

Todd Matsubara
TM Engineering LLC
www.tmengineering.net

Lvangundy

This thread is getting pretty analytical.

I'll just post my latest observations..

I connected the speakers 'bridged' and wired them in parallel (i think- or series?) The only problem I've seen is that you can't turn the bass boost up on the deck ot the amp very high when they are bridged becuase the amp cuts off until I turn the bass boost back down a notch. According the the amp specs, it should be putting about 80W bridged.

Another thing with these speakers is that they had a problem (as designer explained) with the VC's heating up and making the speakers pop. I witnessed this when they started hooking up 600W into each speaker, the cone would extend and create a superloud pop noise. It made my friend jump back like he was gunna get hit by something LOL..

Here's a little drawing of how they are connected. The sound is much stronger now, and not so distorted. Colors for fun..

BabaBooey

"If a speaker is underpowered, it will be clipping the amp like 90% of the time if the person doesn't know any better on how to control the volume ****! That is what can and will damage a speaker."

Well then that would be a problem with ignorance, no amplifier design.

"Improper VC cooling?!??! What do you do? Put a fan on your speaker?!?! Get a clue man, it's super high voltage or square waves that cause them to get unreasonably hot. Once again, most people won't have super high voltage going to their speakers."

I believe you're the one that needs to get a clue. What do you think a vent is for? While an amp is being clipped, current is repeatedly flowing through the voice coil. This causes the VC to heat up. All the while, the cone/spider remain extended. Since the cone isn't returning to the original position, it isn't going to be able to push warm air from around the VC out of the vent.

"Overexcursion? I don't think you have seen or been in the presence of true overexcursion."

I've plugged a freeair 10w0 into a wall socket...

"Example, I built a car with 3 10's in it, each was powered by an amp that put out about 900 watts. The tweeters were powered by 600, and the mids were powered by another 600. This system could play ALL DAY LONG at high volume like this. These were not some overrated cheesy amps either, they were some pretty big zapco units."

I never said that properly overpowering speakers could be a problem...

"They are obviously asking for help for a reason, and you are leading them in the wrong direction. This type of misinformation is what makes message boards such as these quite dangerous."

You are certainly contributing to misinformation on the board...

Sorry I'm halfassing these answers, the Saints game is on. I'll continue to do what I can though until the game is over, then I'll be able to give appropriate responses...