Amp Clipping Issue

[jinjuku]

Sure, but with the -3dB point at 38Hz, you really need a lot of them and a ton of power to do 105@20Hz. There are other designs for that kind of cash that can do it with two subs, though.

For $850 you can put in six dual opposed. A single d/o models at 105dB at 20Hz before hitting X-max at 350 watts. Six of them? that could mean ~112-115dB in room and with good placement naturally flat response. What will do that commercially for $850?

Not saying everyone has that flexibility of placement. But I could in my room easily do four.

 

[panteragstk]

For $850 you can put in six dual opposed. A single d/o models at 105dB at 20Hz before hitting X-max at 350 watts. Six of them? that could mean ~112-115dB in room and with good placement naturally flat response. What will do that commercially for $850?

Not saying everyone has that flexibility of placement. But I could in my room easily do four.

My question to you is what should I do to fix this? I built my boxes with scrap wood so I'm not opposed to your dual opposed design (see what I did there?). You think running 775w through each is too much? The drivers don't seem to mind.

I'm going to re-wire them to run at 8 ohms instead of 2 and see if the problem still happens. This was an experiment since they were so cheap, so buying two more drivers isn't exactly out of the question.

Or, would buying a better driver be a good idea? I like the small footprint of my current boxes, and I eventually wanted to put LMS-R 12's in each box and buy another xls1500 to power them. That or go cheap and get the Kappa 120.9w's since they have a higher xmax.

I won't be buying a commercial sub, so that's out of the question. I'm getting too good of performance (with the exception of this issue) for how little this project cost. Plus, this gives me something to do.

Thanks a lot to everyone so far. Really appreciate the help.

 

[jinjuku]

You need more driver in the case of the 126X series. It's a good bang for the buck but it's still only going to go so far. You are going to add more surface area and reduce signal by 3dB. You can't correct what is on the WOW sound track, just work around it. You still need to see what your room is doing frequency wise.

So that is my rather limited knowledge guess about your scenario/setup w/o going to measures that you may not want to spend the coin on.

 

[avengineer]

For $850 you can put in six dual opposed. A single d/o models at 105dB at 20Hz before hitting X-max at 350 watts.

At 1 meter? Or at the listening position?

Six of them? that could mean ~112-115dB in room and with good placement naturally flat response. What will do that commercially for $850?

Not saying everyone has that flexibility of placement. But I could in my room easily do four.

Yeah, not everybody. I can hardly talk people into 2, but you're right, that would do it.

 

[avengineer]

You need more driver in the case of the 126X series. It's a good bang for the buck but it's still only going to go so far. You are going to add more surface area and reduce signal by 3dB. You can't correct what is on the WOW sound track, just work around it. You still need to see what your room is doing frequency wise.

So that is my rather limited knowledge guess about your scenario/setup w/o going to measures that you may not want to spend the coin on.

For a lower cutoff and higher output in a sealed box you need a lower Fs and higher Xmax. Adding more drivers doesn't change Fs. Not sure about the dual-opposed idea, though, that could work.

 

[panteragstk]

You need more driver in the case of the 126X series. It's a good bang for the buck but it's still only going to go so far. You are going to add more surface area and reduce signal by 3dB. You can't correct what is on the WOW sound track, just work around it. You still need to see what your room is doing frequency wise.

So that is my rather limited knowledge guess about your scenario/setup w/o going to measures that you may not want to spend the coin on.

This is where my limited knowledge comes into play. I do need to check the room itself just as you say. What is the best method?

 

[jinjuku]

1 meter since obviously I don't know what his room is like nor his seating distance

 

[jinjuku]

For a lower cutoff and higher output in a sealed box you need a lower Fs and higher Xmax. Adding more drivers doesn't change Fs. Not sure about the dual-opposed idea, though, that could work.

It doesn't change Fs but it does increase output and allow either pre or amp to come down a bit IF being run hot by either gain or material.

 

[jinjuku]

You need to run power response sweep and measure the SPL output. Again if it's only WOW that is causing this I really think your cheapest solution is adding more driver.

 

[markw]

You need more driver in the case of the 126X series. It's a good bang for the buck but it's still only going to go so far. You are going to add more surface area and reduce signal by 3dB. You can't correct what is on the WOW sound track, just work around it. You still need to see what your room is doing frequency wise.

So that is my rather limited knowledge guess about your scenario/setup w/o going to measures that you may not want to spend the coin on.

I think this point went over someone's head.

 

[panteragstk]

I think this point went over someone's head.

Not mine, I just didn't acknowledge it. Sorry. Obviously can't change a sound track. I just want to make sure what I have is working properly.

 

[markw]

It is. You just found your systems limits. You really didn't pick up on that yet?

 

[jinjuku]

Ok, lets be nice now... Yes I am getting at the fact that with the budget driver the limit has been reached with TWO of them. Now a few dual opposed will raise the performance bar and may give you what you want.

 

[markw]

I hear ya, but...

From post 1

At fist I thought I had the gain too high. After lowering it all the way to half the issue still happens when torture testing (war of the worlds). I haven't been able to get any other movie to recreate the issue, but I still want to make sure there isn't an issue.

What is "workig properly"???

If it's the source itself, the how will more power, more drivers, or anything cure his WOW complaint?

Sometimes, one simply has to face the simple fact that that's just the way it is?

Now, if he wants more drivers and more power, do you really think that will cure his complaint?

In any case, as for "improving" the system, he's got quite a bit of input here on how to do that. but it still ain't gonna cure his problem. ANY system can be driven beyond it's limits if one tries hard enough.

 

[jinjuku]

Now, if he wants more drivers and more power, do you really think that will cure his complaint?

I understand completely but it may assuage. I am making the assumption that there is overall a SQ issue. Now nothing is going to stop a .1 track that is mastered too hot. BUT when you increase the mechanical sensitivity of a system by 3-6dB it does allow for some triage at the amp or pre level.

I don't know if the track is clipped or not. I'm just trying to help the OP out with the least amount of pain. And lets face it doubling up on drivers doesn't have a lot of downside

He's asking for things to try and thinking giving him more head room via additional drivers isn't unreasonable considering the cost. Now I consider $150 quite nominal but that is thinking with my wallet and not an others.

His other option is to engage the Peak-X limiters.

 

[markw]

I don't know if the track is clipped or not.

IMNSHO, from OP saying it still does it at half level as well, i'd say it is.

 

[jinjuku]

I don't see how it could make it out of post production. I would want to see an signal analysis. That would be interesting.

 

[markw]

I don't see how it could make it out of post production. I would want to see an signal analysis. That would be interesting.

Well, the fact that no other disc does ii and it even does it at half volume, it's either that or a f'ed up DAC in the pre-pro.

 

[jinjuku]

You are probably right. Just in disbelief. I'll get over it

 

[markw]

You are probably right. Just in disbelief. I'll get over it

It could have been ruled out by trying that disc on another system, particularly since OP says they did torture testing on another system, with other discs, but not that one.

...that would have narrowed it down to either the disc or the DAC, but no...

I guess that when one only has hammer, every problem looks like a nail.