Okay so i went to a store and they said that the distortion that i was hearing is because i was running too much power to the sub- then they demoed one in the store that was matched to a amp and it made the same distortion when i turned it up  .  i am sick of this why cant a 1000 watt woofer take 1000 watts? As long as the signal is clean , the woofer should be able to take what it is rated at without distorting.

If i have a 1000 watt amp and woofer, should i be able to turn the gain up all the way and as long as the amp isn't clipping, could the woofer take it without distorting or am i missing something?

Okay so i went to a store and they said that the distortion that i was hearing is because i was running too much power to the sub- then they demoed one in the store that was matched to a amp and it made the same distortion when i turned it up  .  i am sick of this why cant a 1000 watt woofer take 1000 watts? As long as the signal is clean , the woofer should be able to take what it is rated at without distorting.

If i have a 1000 watt amp and woofer, should i be able to turn the gain up all the way and as long as the amp isn't clipping, could the woofer take it without distorting or am i missing something?

No

Okay so i went to a store and they said that the distortion that i was hearing is because i was running too much power to the sub- then they demoed one in the store that was matched to a amp and it made the same distortion when i turned it up  .  i am sick of this why cant a 1000 watt woofer take 1000 watts? As long as the signal is clean , the woofer should be able to take what it is rated at without distorting.

If i have a 1000 watt amp and woofer, should i be able to turn the gain up all the way and as long as the amp isn't clipping, could the woofer take it without distorting or am i missing something?

No

Okay . so what is the deal? does the amp put out more than its rated power or something?

I don't mean literally turn the gain up all the way, just up until the amp is putting out its maximum power.   

 

Okay so i went to a store and they said that the distortion that i was hearing is because i was running too much power to the sub- then they demoed one in the store that was matched to a amp and it made the same distortion when i turned it up  .  i am sick of this why cant a 1000 watt woofer take 1000 watts? As long as the signal is clean , the woofer should be able to take what it is rated at without distorting.

If i have a 1000 watt amp and woofer, should i be able to turn the gain up all the way and as long as the amp isn't clipping, could the woofer take it without distorting or am i missing something?

No

Okay . so what is the deal? does the amp put out more than its rated power or something?

I don't mean literally turn the gain up all the way, just up until the amp is putting out its maximum power.   

How do you determine when the amp is putting out max power?

Okay so i went to a store and they said that the distortion that i was hearing is because i was running too much power to the sub- then they demoed one in the store that was matched to a amp and it made the same distortion when i turned it up . i am sick of this why cant a 1000 watt woofer take 1000 watts? As long as the signal is clean , the woofer should be able to take what it is rated at without distorting.

If i have a 1000 watt amp and woofer, should i be able to turn the gain up all the way and as long as the amp isn't clipping, could the woofer take it without distorting or am i missing something?

No

Okay . so what is the deal? does the amp put out more than its rated power or something?

I don't mean literally turn the gain up all the way, just up until the amp is putting out its maximum power.

How do you determine when the amp is putting out max power?

Exactly. I thought it was just until it started clipping, then turn it down a little. obviously i was wrong. I have never heard any clipping, so i thought i was golden lol Heres some pics of my amp and setup . Let me know if you see something i could improve on

Edited May 15, 201312 yr by Trent Hari

Set the gain by ear.

 

Ditch the cap.

Alright so the amp will overpower the sub. got it. 

 

I got the capacitor back when i didn't know anything and im kinda emotionally attached to it hahaha.

Will it hurt my audio performance? If not i don't see any need to get rid of it and it looks cool if nothing else.

It may.  If it hides a problem from you and you ignore your ears which it sounds like you are prone to then yes.  Remove it fast.

///M5, on 15 May 2013 - 20:37, said:

It may. If it hides a problem from you and you ignore your ears which it sounds like you are prone to then yes. Remove it fast.

Alright. How would a capacitor hide a problem? I don't ignore my ears obviously because i am complaining about distortion. Maybe I should just sell the SA-12 and get 2 Alpine Type s's (Or 2 sa-8's or....?) I think im trying to get too much output from one woofer and so i'm overpowering it. (what u think?)

My speakers are really clear and loud, I just love the chest-thump feeling that sub creates , and it doesn't hurt my ears when i turn it up.. Its the weak point on my system currently. If you look at the pic of my sub box, you can see its a pretty small ported box (1 cu ft). Would a larger box significantly increase SPL or SQ? I really don't want it completely filling my back seat though

Btw i think my amp has a protection deal where it will not clip (or something). I had the gain on the amp up 100% and then i turned the deck gain up all the way at a stereo shop to let a employee see if it was clipping . the sub got really loud, but after a point, it didn't get any louder even though i turned the volume up more. There was Still no clipping. not sure what the deal was but just an interesting note. please don't flame me if this sounds dumb, its just an observation.

Edited May 16, 201312 yr by Trent Hari

You could have a voltage problem, you just don't see it.

 

You are clipping the hell out of your amp if you are hearing distortion.  That or your box sucks.  Of course the third option is both.

 

And there is no such thing that you think your amp has.  And yes there was a ton of clipping you just didn't hear it.

 

Lastly, you keep stating SQ/SPL.  Stop it.  You have no idea what either term means.  Read the threads in my signature.  For a sub they are exact opposites.  Super peaky box or super smooth frequency response.  You CANNOT have both.  You must compromise.  Doesn't mean that an SQ setup can't be loud without compromise either, but it is FAR from an SPL setup.

You could have a voltage problem, you just don't see it.

 

You are clipping the hell out of your amp if you are hearing distortion.  That or your box sucks.  Of course the third option is both.

 

And there is no such thing that you think your amp has.  And yes there was a ton of clipping you just didn't hear it.

 

Lastly, you keep stating SQ/SPL.  Stop it.  You have no idea what either term means.  Read the threads in my signature.  For a sub they are exact opposites.  Super peaky box or super smooth frequency response.  You CANNOT have both.  You must compromise.  Doesn't mean that an SQ setup can't be loud without compromise either, but it is FAR from an SPL setup.

Yeah My box sucks. That's what the person at the store said. There's not enough air volume for the sub to work properly apparently. If you noticed, i said increased SPL OR SQ, not both at the same time. I wasn't sure what a larger box would create for my setup. What do you think about me getting multiple smaller subs for more audio volume?

Yes i do know what SPL and SQ mean-  I don't use terms that I don't have a clue about and if I do I ask for a definition. 

 

My cap has a volt meter on it, i know i'm still getting a hell of a lot of voltage drop at the cap (down to 13 volts sometimes) , maybe because i only have one run of 4 gauge to the battery? (The volt meter on the dash doesn't fluctuate much though) I just don't want to start drilling holes trying to get another battery in my truck, that's why i have a cap, it was the only thing that would fit under that seat. Also i'm powering both amps off of that cap, would it me smarter to just run the PDX-5 directly to the battery? 

 

(I'm looking for a more conservative setup, not one where i have 4 batteries and a wall of subs in my truck)

Edited May 16, 201312 yr by Trent Hari

One thing I see that has been overlooked here, Trent you are very fixated on matching rms ratting of the sub woofer to the wattage ratting of the amplifier.  Music is dynamic, so it is quite rare that your amplifier will be sending 1000 watts of power to the sub woofer.  Not to mention impedance rise from the enclosure etc. etc., but that is a different topic.

 

Anyway, what I am getting at is we, for example, (SSA) have people running 2000 watt ratted amplifiers to SSA Icon's, and 1000 watt amplifiers to SSA Zcon's.  Moral of the story is not to focus on matching the ratings on the amp and sub and set your amplifier gains correctly, along with the gain is not a linear adjustment to the amplifier wattage output.

I'm wondering what you think clipping is? Clipping IS distortion (one of many forms) and is caused when the input signal attempts to drive the output signal above the voltage it has available. The gain is ONLY there to match the amplifier's input to the output voltage of the HU. When you turn the volume up and exceed the level the amp has been adjusted to, or simply have it adjusted too high it will clip the signal. For simplicity lets say the amplifier is like a transformer, but unlike a transformer the voltage can only go as high as the power supply voltage is. So say it's a 4x transformer (much like a reversed 480 to 120 control transformer), if you put 5v into it you'll get 20v out, pretty simple right. Now, let's say the the power supply limit is 20v and you put a 6v input signal into it, (6 x 4 = 24v) that 4v that it's trying to output gets clipped off at 20v because that is all that's available to it.

While it's a much more technical and sophisticated difference than what I just explained that is essentially what you're running into with clipping. If the amplifier's power supply converts the 12v voltage in your vehicle to 70v, that's a 35v positive and 35 negative limit for the signal, which for a sine wave (what all sounds are) is just how it works and is why it's measured in AC voltage even when everything in your car is DC. When the gains are adjusted the idea is to match the output voltage from the HU at that volume level to get that 70v from the amp. Differences in the recording levels of the material you play, the point where you turn the volume to, etc. all play a part in whether or not you exceed that or not. If you turned your volume up to 30 to set the gain with a -6db tone, when you play music that has peaks that reach -3db in their recorded level those peaks are clipping the amp even with the volume set to the same 30 level.

That is the way of it. I'm not sure how to explain it any simpler, but if you're constantly pushing the sub into distortion, barring any issues with the sub, enclosure or amp themselves then you simply need to identify the limiting factor(s) and upgrade them accordingly. You very well may be expecting more from the SA than it can possibly give.

" You very well may be expecting more from the SA than it can possibly give."

Yes that is probably it. that is why i was asking about replacing it with two lower-power subs for more output.

No one seems to be commenting on my box. that thing is awful. maybe some advice on that subject would help. would a larger box tuned correctly create more output?

 

I am not 100% sure on what clipping sounds like, but people that DO know what it sounds like say its not clipping. ("professional installers" lol)

I would take the addition of the word "professional" with a grain of salt and a lot of caution if I were you.  I've met "professionals" in shops who were doing installation related NO NO's that I knew were no no's when I was still in High School (almost 16 years ago) and that wasn't but a year or two ago.  There are a lot of common practices that are done by many people, even in shops, that are just plain wrong.  Just as many of those folks who are doing that wouldn't know distortion from a panel rattle, active from passive processing, or how to properly spec an enclosure for a given subwoofer AND the application it's going to be used for.  Just because they work in a shop don't assume they know their shit beyond any doubt.  Ask them to explain exactly what clipping is and if it's not at least remotely close to what I described then they don't know what it is much less what to listen for to identify it.

 

A proper box will always yield better results than a wrong one.  If you want a good enclosure designed for that SA 12 then we can probably help with that, true enough.  Who would be building it?

I'm not sure who would be building the box. probably a local audio shop. I do have some serious size constraints though I do like to have a usable portion of my back seat.

Dimensions that would be good for me - a wedge- style box - let me know what it would take if i HAVE to go bigger- Material- 3/4" MDF

8" depth top

12" depth bottom

16" tall

30" long

Ported if possible - tuned to optimal frequency for SA-12 - I'm not sure maybe 30 hz

I created one in autodesk inventor but I don't know how to upload it.

Edited May 17, 201312 yr by Trent Hari

The gain on the amp is to match the amps voltage input with the output of the headunit. The rms rating on the amp is rated based on the power that the rails on the amp can generate. When you crank the gain too much it causes the amp can not keep up causing the output signal to be destorted.

Almost all subs are rated at 70%BL which relates to 20 percent distortion. And if you are running a high xmax sub like 30mm or so you are actually getting into the 40-50% distortion realm as nearly all 8 inch spiders being used today hit 20% distortion at around 18mm.

For reference 20% distortion is what is considered becoming audible. However most people have these high xmax subs and never complain about any audible noise which can be clearly be seen by having the driver tested on a Klippel analyzer.

What does this mean? It means that most people's consent of distortion greatly veary and what a lot of engineers will tell you that distortion can actually be a good thing. In fact distortion is a tually purposely induced in some drivers, for example guitar amps.

Where I am going with this is, you would have to seriously clip a sub into distortion to have it audible. More than likely you are just driving the sub past its mechanical limits which is directly related to power which will change greatly depending on the enclosure volume and tuning.

Got it . any advice on that enclosure I mentioned?

Dimensions that would be good for me - a wedge- style box - let me know what it would take if i HAVE to go bigger- Material- 3/4" MDF

7" depth top

12" depth bottom

16" tall

30" long

Ported if possible - tuned to optimal frequency for SA-12 - I'm not sure maybe 30 hz

I'm mobile at the moment and I would have to model it. Seems like you are trying to get as much loudness as possible? If so I would design a box with a 3db ripple in the frequency response in the mid 30's. ill take a look at it later tonight.

Yes I would like SPL but nothing crazy I'll sacrifice a little volume for good SQ

I may even install a different sub at some time in the future. (SSA icon or death row) if a box only works for one sub don't worry about it,.

Yes that is probably it. that is why i was asking about replacing it with two lower-power subs for more output.

And just like with your door speakers that won't be the cure. You need to stop guessing with cone area and power and think that you have a solution. It is simple, but not that simple.

I would build the enclosure 1.75 cubic feet net tuned to 32 hertz.  This will give you a 3db ripple (boost) at 35 herts and give you a F3 (-3db) at 26 hertz.  This will give you the sense of exaggerated bass output.  You can go smaller down to 1.25 feet but keep tuning at 32hz and do not go over 1.75 feet as group delay would be higher than desireble. 

I would build the enclosure 1.75 cubic feet net tuned to 32 hertz.  This will give you a 3db ripple (boost) at 35 herts and give you a F3 (-3db) at 26 hertz.  This will give you the sense of exaggerated bass output.  You can go smaller down to 1.25 feet but keep tuning at 32hz and do not go over 1.75 feet as group delay would be higher than desireble. 

Sounds good! That sounds like what I want   Could I see a design? I'm not sure on port length and  all the little design tricks to creating a sub box

or maybe recommend a free or low-cost program that helps with calculations and box dimensions although you guys would probably cringe at the design i come up with.

 

What would it cost for you guys to build that "optimal sub box" ?- I just saw that you are a vendor-  Quentin Jarrell

 

I can get a 1.3 cubic foot prefab for about 60 bucks that's tuned to 36 hz (Bassworx TP 12) or is that not even close for what would work? the only reason i ask is the difference in price might be pretty dramatic.

Edited May 17, 201312 yr by Trent Hari

I created a thread under the SPL/SQ Fabrication topic about a design for my sub-woofer box.

That $60 prefab is a pile o'donkey dung.