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Discussion Starter · #1 ·
So I am running these pyle 15s IB, they have great IB specs. They work fine for normal music and hit 30Hz no problem, quite flat in response. I have a couple threads here on the install and a review.

The issue is they seem to get quieter at high volume and I am wondering if they are coming out of the gap, is there a way to tell?

I'm happy with them anyway, for the price they work really well. What happens is the HU is set to run roughly 50 volume depending on the source and be clean. At above 40 it is like the sub is not keeping up like it was. I can turn the sub level up and it goes louder and keeps up just fine. IMHO above 40 mark is not really SQ it is quite loud, only play it there to hammer a song once in a while anyway. This would be playing music with quite a bit of bass lets say a top40 song, strong bass to 30Hz, and with the 350rms on it. It can get a lot of bass but that is about it with 350w and 4x125 on highs and no clipping I can detect by ear at that volume.

Now when I had the 500rms amp on the subs it acted the same, except I could turn the level on subs up higher and higher and it would shake the roof and mess up my ears, it would overpower the highs significantly. With a bass Cd it would make even more bass it was like I could not get enough gain on them to get full output. I had the 500 (alpine mrd-m500/m301 amps) at max gain and the 350 is also, typically run zero level on the HU give or take and it goes to +6. EQ is boosted at 20Hz just +1. I have to move the level higher than 0 when I get over 40 volume to keep the same bass.

Far as xmax I have to take the seat out to see them well, but with the 500rms at any (IMO) SQ volume they were under 1/4" total excursion. Really banging on it they would see more and when this effect seems to happen. I had figured dropping to 350rms would make much or all of it go away if this was the case but it didn't change it that much it just cut down the overpowering output it could get before. Had also considered a larger amp would gain more as volume went up and maybe the smaller one would be worse, but that is not the case either.:confused:

It is possible they only have ~8mm of xmax (?, or whatever) and the rest is xmech for all I know. I ran one unmounted when I got them on a 170rms amp bridged, tones from 20-50, and could estimate 1 1/8" total cone movement for sure (so I guessed that up to half that would play fairly clean in the car). They didn't seem to want to go above that with additional power, though I may have been clipping that amp it did have some left. I doubt it gets that high even with the 500rms on both mounted in the car. Could see it got lot less xmax once mounted. I can't get near the xmax on music only with tones or a bass CD will they get moving a lot, something 0dB. HU is a 880PRS. Also ran a kenwood 9504D for a little while and was very similar to the 500 alpine. By ear they play flat to under 30, they drop off a little at 25 and roll off under that though 20Hz is hard to 'hear' anyway but something is there. I have not had too many sub setups that would pump under 30 like this so no recent comparisons to make to it, but I like it.

They might change tone and lose some of the lowest bass when the 500w leans on them hard, I can't be sure it is so loud I can't hear the tones precisely but will guess that is the most you want to run (250rms each). The 350 does not seem to it just stops getting louder at a point and sounds about the same in tone. The 350 will loose some punch at full output so it may be starting to clip, compared to the 500. Run no SS filter so they get deep as possible, but have a feeling the amps don't make that much under 20 anyway. Really I don't care if SQ is perfect over 40 on the volume its louder than I need, but this gain thing is a pita I need a remote for the amp and don't really want to have to screw with it....and want to know why more than anything.




 

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I'd seriously doubt if they had even 8mm Xmax.

Coil coming out of the gap won't lower the volume. It will just stop increasing it as much until your signal either peaks or the sub bottoms, causing distortion. (This might not be the case if it was by a LARGE margin, I suppose...)

My guess is some sort of phase issues.
 

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Most car amps these days use a circuit that cuts power if the amp gets hot or is pushed too far. There are good ways to do this and bad ways to do this. The bad way is audible and sounds exactly like what you're describing. The good way has a smooth transition and operates only when the amp is hot, not as a simple limiter. I think this is the "problem"
 

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Discussion Starter · #4 ·
That is why I don't understand this, with the 500rms the subs will go significantly louder. I can turn the level way up and have very heavy bass at 50 (max clean on highs roughly) enough to shake the roof and make it hard to hear the highs. When I turn it back down under 40 it has even more bass compared to the highs, then I turn the level back down.

I guess the amps are the same model but not sure how heat would be a factor. It does not matter how long I have had the system on. The amps are on a shelf above the subs with two PC case fans blowing into the center and out both ends over the amps. The kenwood was the first amp I ran, was not very familiar with the subs at that point so not entirely sure if it did this. But I have other amps to run, including a 600rms infinity and a different alpine M650, maybe others.

This is the 500rms and a 4x50 dragster I had in there before the kappa 4x125


I've added some power blocks still working on the wiring lol. The wire nuts run the fans and amps off a 10A relay I had to solder wires on not sure how to mount that yet.

You know what I better see what wire size I have to the subs a calculator is saying 16ga is too small but not sure what I used....it looked larger lol but in that photo it looks tiny. That would affect high output and not lower power, just seems like 500>>350 change would show less affect? And it does not seem to.

Bah:blush:, the wire is 16ga why did I put that in there, and the subs are wired one to the other. I have some 12ga around here I will dig up and put on there, what a rookie move. I didn't originally think the pyles would handle 500rms, likely was going to double the 16ga and call it good but I never did. It still shows less than 0.2dB loss in output worst case with 500w.:confused:
 

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the only problem you'd face with the wire gauge would be heat generation, it's not limiting you... not at this level and distance...

I don't know what IS, but it's not 16awg wire to your subs over 3ft..
 

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Discussion Starter · #6 ·
About 2' of wire to first sub maybe 2' between them. I hate to think the amps are doing this, or the HU. Everyone says volume should be linear (sub to highs).

I can't think of a way to estimate VC travel, far as I know you need a klippel/etc.

Not sure why I get 1"+ xmax on a 170rms Dual amp if the VC was so short. I thermalled that little amp lol, it was one I put new outputs in must have fixed it right. But I have no idea how much being unmounted unloads the cone, they didn't get xmax as easy mounted IB but that makes sense you have no cancellation.

When the kicker 700.5 (4x70/1x420) was in there and the quad infinity 12s IB I did not have this problem. Way too much other crap here right now but I'll try to swap the wire and the sub amp soon as I can, will dig out the stuff tonight. I can toss the kenwood 900rms in there, I took it out because they didn't seem to get low enough but after the alpines I don't think it changed much but has been a while. Since the k-wood is a budget amp was thinking it might have internal SS filter to help power ratings. I have seen a test on the older model for over 650rms on 13.5v iirc.

Also have a huge soundstream class AB, must be a 90s amp its all silver a XTA880.2. Do not think it would fit in my amp rack however lol. Its 880rms bridged or so it says. Could run it stereo at 220x2 with my pair of 4 ohm subs.
 

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Xmax is not the same as excursion. Xmax is linear excursion. Your actual limit will be above Xmax but not more than Xmech. Xmech can be twice as high as Xmax or sometimes even higher. Exceeding Xmax is going to hurt sound quality but it can be done. But it shouldn't bring the volume down unless your coil is leaving the gap so much that it's spending a lot of time in 'limbo' without magnetic forces acting on it, similar to what a highly clipped signal would do. But even then, the suspension shouldn't be allowing the driver to remain in limbo for very long at all...
 

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I have an extra set of Pyles in the garage if you need something to test with..lol...

You can't be THAT far away... lol... I could use your tuning help anyway..
 

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About 2' of wire to first sub maybe 2' between them. I hate to think the amps are doing this, or the HU. Everyone says volume should be linear (sub to highs).

I can't think of a way to estimate VC travel, far as I know you need a klippel/etc.

Not sure why I get 1"+ xmax on a 170rms Dual amp if the VC was so short. I thermalled that little amp lol, it was one I put new outputs in must have fixed it right. But I have no idea how much being unmounted unloads the cone, they didn't get xmax as easy mounted IB but that makes sense you have no cancellation.

When the kicker 700.5 (4x70/1x420) was in there and the quad infinity 12s IB I did not have this problem. Way too much other crap here right now but I'll try to swap the wire and the sub amp soon as I can, will dig out the stuff tonight. I can toss the kenwood 900rms in there, I took it out because they didn't seem to get low enough but after the alpines I don't think it changed much but has been a while. Since the k-wood is a budget amp was thinking it might have internal SS filter to help power ratings. I have seen a test on the older model for over 650rms on 13.5v iirc.

Also have a huge soundstream class AB, must be a 90s amp its all silver a XTA880.2. Do not think it would fit in my amp rack however lol. Its 880rms bridged or so it says. Could run it stereo at 220x2 with my pair of 4 ohm subs.

I can give you my Infinity which will do 1,[email protected] if you need it for testing. It plays a 7hz test tone no problem. I was planning on giving it away as soon as the 900/5 gets here anyway.
 

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That is why I don't understand this, with the 500rms the subs will go significantly louder. I can turn the level way up and have very heavy bass at 50 (max clean on highs roughly) enough to shake the roof and make it hard to hear the highs. When I turn it back down under 40 it has even more bass compared to the highs, then I turn the level back down.
Could it be that the FR of the deck changes between the 40 and 50 settings?

I've got the 980BT and I've noticed a similar response change between 40 and 50 (the deck tops out at 62). I put it down to either a response change at the deck's output, or the subs going non-linear at greater volumes, but the latter doesn't explain why it's noticeable on tunes that do not have enough bass to get the subs significantly moving at level 50.

I'm tempted to just turn the gains on the amps up a bit and plan around getting peak output when the volume is set to 40 on the deck :).
 

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Discussion Starter · #11 ·
Xmax is not the same as excursion. Xmax is linear excursion. Your actual limit will be above Xmax but not more than Xmech. Xmech can be twice as high as Xmax or sometimes even higher. Exceeding Xmax is going to hurt sound quality but it can be done. But it shouldn't bring the volume down unless your coil is leaving the gap so much that it's spending a lot of time in 'limbo' without magnetic forces acting on it, similar to what a highly clipped signal would do. But even then, the suspension shouldn't be allowing the driver to remain in limbo for very long at all...
The subs are not floppy, I only dare push hard enough on the cone to get about half the travel 170rms does on a tone. Seems like distortion would be really high if the VC was that short.
I have an extra set of Pyles in the garage if you need something to test with..lol...

You can't be THAT far away... lol... I could use your tuning help anyway..
You need quads in your car :cool: I did turn the TA back on today and set it by ear, but don't think it affected the sub. I did change the EQ around but then had to get to work.
I can give you my Infinity which will do 1,[email protected] if you need it for testing. It plays a 7hz test tone no problem. I was planning on giving it away as soon as the 900/5 gets here anyway.
I have a 400rms alphasonik 10 ported to 27hz I test amps on, and a 600rms Cerwin 10 I could use. Also a pos P5 sony 12 sealed that is kind of spl, but does not unload on amp tests. Not really wanting to run something not IB though, I need the trunk in that car and I love the bottom they have. Thinking I would be laughing at a 10 in there, or have to build a big box to use something else just to test. I'll ask a buddy of mine if he has any boxes laying around he did have some dual 12 BP boxes.
Could it be that the FR of the deck changes between the 40 and 50 settings?

I've got the 980BT and I've noticed a similar response change between 40 and 50 (the deck tops out at 62). I put it down to either a response change at the deck's output, or the subs going non-linear at greater volumes, but the latter doesn't explain why it's noticeable on tunes that do not have enough bass to get the subs significantly moving at level 50.

I'm tempted to just turn the gains on the amps up a bit and plan around getting peak output when the volume is set to 40 on the deck :).
Hmm, possible I don't recall what I ran it at on the kicker but thinking I had it 40 max. Because the volume is so slow and I really hate that. I have a scope but I'd have to pull the HU and hook it up on the bench, run tones and see if the voltage output changed. Hard to believe it would, but possible. IIRC it goes to 64 or something?
 

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I have a 400rms alphasonik 10 ported to 27hz I test amps on, and a 600rms Cerwin 10 I could use. Also a pos P5 sony 12 sealed that is kind of spl, but does not unload on amp tests. Not really wanting to run something not IB though, I need the trunk in that car and I love the bottom they have. Thinking I would be laughing at a 10 in there, or have to build a big box to use something else just to test. I'll ask a buddy of mine if he has any boxes laying around he did have some dual 12 BP boxes.
Sorry I mean an Infinity amp.
 

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You need quads in your car :cool: I did turn the TA back on today and set it by ear, but don't think it affected the sub. I did change the EQ around but then had to get to work.

That's why I said TEST... :laugh:

Quads can wait till spring now...
 

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Discussion Starter · #16 ·
That's why I said TEST... :laugh:

Quads can wait till spring now...
This is MI you can take some time off the video games and forums, go out to the shop and get the heat going, play a game for an hour, go back out to a warm shop and build a new baffle, only take a couple evenings, plug in the trickle charger for a while too, etc. LOL:laugh:

Those are real prime oven shelves! The seat frame is not very complex, I could push it into the sub if I tried though it does not with a normal person sitting there. But never know when I might toss something large in there against the seat or something.....had to protect my $94 investment lol. Actually the install was intended to swap to better subs if needed.

Pretty sure I don't need over 500rms, 400 might be enough. They get almost violent on 500 though it might be to the point where SQ is starting to suffer. I'm not a bumper so to me it was more than I can handle anyway, screws with my ears, not good. 500rms goes so much louder than the highs that is why I can't figure out this volume issue. The whole idea with these was low xmax means low distortion, the subs would never be stressed in normal use, so sure they should go louder than I need to tell me I'm still in the SQ range of their capabilities. Pretty sure with higher xmax they are not going to perform like a better sub but the idea was not having to go there with a pair of 15s. So either they are cheaper built than I thought, or something else is causing this. Far as SPL they fail at the lowest frequency first so technically that is where SQ will drop but hard to hear problems down there.
 
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