Need some suggestions

[jmoney22420]

No worries.. again sorry.. seem to be having a problem post my own thread

[Low_Psi]

I had the gain set really low, to break in. But I had a Rockford T1 12 that I tried to recoil. So the gains were set low to break the Rockford in. I haven't touched the gain since. The recoiled sub ended up not being aligned very well and was scraping the coil in the gap (I am not sure what happened as I shimmed the coil properly....). It ended up blown, and I assumed it was due to the epoxy being scraped off. So I ordered the SQ sub and while I was waiting for it to be delivered I used the Alpine R series sub out of my car. Well I cut that old Rockford sub apart last night to see the condition of that coil. It was pretty burnt. So I am wondering if the gain hasn't walked itself higher. Now I realize that sounds crazy but it is mounted in an offshore boat and it does see a lot of slamming and vibration. I will have to take a look at the gain on that amp as I am now leaning toward it being up too high and causing clipping...... Which if the case, I guess I will end up paying to have the SQ sub rebuilt. I still find it odd that the entire coil came uncoiled and there is virtually no hint of epoxy on the former.........

[reedal]

How do you determine where to set your gain though? While it might be low it could still be too high. Are you just guessing or using the 3/4 rule or are you using a proper tool to measure distortion and clipping from the head unit and amp?

[Low_Psi]

I had it set maybe at 1/4. But I am am thinking it has walked due to vibration, being it a boat.... If that's the case, I will have to figure a way to fix the gain in place. I am guess here. I won't really know until I get down to the boat in a few days. As far as how I set it, I normally will set it by ear. But since I was originally breaking in a new coil on the Rockford t1-12 I had turned it way down so I could break-in the new suspension. But since I had the issue with alignment, I put my alpine R series in while I was waiting for the new SQ to arrive. The alpine R series did just fine, but knowing it wasn't a high powered sub, I made sure to really baby it. Then once I put the SQ sub in, I assumed the gain was still where I had set it... The amp is mounted up high behind the dash, so it's not visible unless I unscrew the dash panel.... So shame on me for "assuming". I plan to pull the dash panel and take a look at the gain setting either Wednesday or Thursday when I have the boat brought down off the rack for me to fuel it up for the weekend.. I just have never seen a sub uncoil like this. And I have blown up many subwoofers back when I was a kid and never seen one do that.

[reedal]

Your source unit could be clipping at whatever volume you turn it up to and you'd never know

[hispls]

This isn't the first thread I've seen on here about the hds300 going slinky.

[Low_Psi]

Could you post a link to the other thread you read that had similar issue, if you run across it? Like I have said earlier, I have never seen this and the coil wire looks bright copper from what I can see. It doesn't appear burnt, yet all the epoxy is gone...... I would be interested in reading what others, who experienced a similar incident, have to say.

[Low_Psi]

Well I may have found the issue. First I did not have the subsonic filter turned on. While I doubt that is the primary reason I am sure it wasn't helping. Here is the bigger issue. The EQ setting on the amp was at 250hz. So the sub was receiving a lot of higher frequencies it wasn't designed for, which probably led to some clipping and certainly more heat due to being overworked. Now I am uncertain if I brain farted and never set it properly or if it had walked due to vibration. The gain seemed to be where I remeber setting it, so I am leaning toward brain fart. I will be taking the boat on a fairly decent ride over the weekend and will inspect the amp settings after to see if it's still where I set it or if it has moved on its own...... I spent some time today dialing in the amp with a repaired Rockford T1-12. Things sounded pretty good, actually much better than they had in the past. I assume this is a result of having the correct EQ settings, plus I did move the box to a different location in the cabin. This repaired sub should hold me over until my SQ sub comes back.

[RainStryke]

Sounds like distortion. If you start smelling your sub, you need to turn it down... I had a pair of HDS312's and they would get stinky if I set the gain up too high on my Hifonics BE1700.1D due to distortion. You can get distortion at even 1/10 gain if you have your head unit set up to add more bass through the equalizer and bass boost settings.

[Low_Psi]

I have my head unit (fusion marine. I'm not sure of the quality of their car audio head units is, their marine head unit is one of the clearest units I have ever used) set very conservative, it only has a 3 bar (I know that's not the right term) EQ, bass, mid, high. Mid is set at 0 and bass at -4, and the sub woofer level was set at just less than 50%. All digital music via internal iPod (I am very picky when it comes to the quality of music. I won't play anything that sounds overly compressed or distorted). So I'm pretty certain the issue was caused by pushing too high of frequency to the sub, causing it to work much harder than it should have. While my goal is to never push my electronics to the point I can smell them, we were on an island while the sub was in the cabin of the boat. Seeing as the boat is 33' in overall length, and we were backed up to the island, we were probably a good 40' - 50' away from the sub, we Never smelled a thing...... Now you may picture the guy at the beach with his stereo cranked all the way up, all distorted so he can hear it 50' away........ That's not me. I am the opposite. We have an Ultra clear sounding stereo On the boat. I am running 4 Rockford Fosgate 8" full range marine speakers and 4 infinity 3way 6x9 marine speakers (these weren't my first choice, they were in the boat when I bought it and actually sounded really good and handles moderate power, so I left them in there) all running off of a Rockford power T600-4 @ 2ohm load. I have been over powering these speakers for almost 2 years now, so that should speak to the lack of distortion. Except for the brain fart I suffered on the Subwoofer amp... I actually just installed the sub woofer this season. Last season I didn't have a sub and most people though I did. They were blown away on the bass reproduction the Rockford 8" full range along with the infinity 6x9s had and the overall clarity and loudness considering it was only 8 speakers....

I do appreciate all of the suggestions and advice that was given. That's what led me to look at the amp settings a bit closer, thus realizing the EQ setting was way to high, along with the sub sonic filter not being set. i will see how my repaired T1-12 handles the new settings. I bought 2 t1-12s from a friend not realizing the coil lead wires were broke on one coil on each sub (he didn't know either, he felt bad and did give me enuff money to buy recoil kits for both). I didn't pay much for the subs (I paid $1k for a Rockford power t1500-1, a Rockford power t600-4, 4 Boston acoustic 6.5 components and the 2 Rockford power t1124 subs). I tried to recoil one and wasn't able to align the coil properly, even using the supplied shims. (It felt fine, however after the cone and surround rubber were glue to the basket and shims removed it had minor coil scrapping in the gap, which was ultimately going to lead to bad things..... So after I was unsuccessful recoiling the first T1-12, I decided to buy the SQ sub and not mess with trying to repair the Rockfords. But since I had to send the SQ out for repair, I decided to perform minor surgery (a few days ago) to the second Rockford T1-12 by cutting a small slit in the top suspension spider and repairing the coil lead. I used shoe goo to re attach the lead to the bottom suspension spider and also used it to seal up the slit I cut. I am not sure how long that will last, it only needs to last until I get my new SQ sub back.....