hrm... if all he's doing is laying plexi over the well and carpeting around the amp... i'm not sure that's worth $200. i hope your explanation to me (based on his explanation to you) is a simplified simplified version...

those guys do a good bit of stuff fairly regularly -- building a small amp rack and installing things? probably a few hours. but i don't know exactly what he's doing, so God himself probably is the only one who knows.

 

Well, I just had it installed, and the mids/highs sound 100% better. Much louder, and clearer. However, the sub isnt too loud. The gain for the mono channel is all the way, the HU sub setting is all the way up, but its not that loud, you can barely hear it from the cabin. Its definatly working, you can see it pumping from the cabin, and hear it, but it isnt loud at all. What could be wrong? We are running both of the crossover chips that come with the amp, high and low. It says it pumps out 200 watts, but apparently, like you stated, thats underpowered, so the sub most definatly shouldnt be. Could they have forgotton to hook up both the voice coils? Could it be wired to a 4ohm load? Any ideas?
gmoore

 

well, there are lots of things that can be going on here...

• where are your crossovers set?
  
• do you have a separate set of RCA's run from both the front and sub outputs on the head unit?
  
• is the sub side of the amp wired off the sub output?
  
• also, what music are you testing with?
  
• what's your bass and treble settings at?

do you have access to test tones?

did the shop tune your system or just install it?

and when you say the sub is moving, how much is the sub moving... if you click my profile, you can see a shot of the e8a moving like crazy in my trunk. that was when it was new and pre-broken in... now, i get even more movement out of it.

that also brings up the next point... when listening to something w/ a strong bass line (dance, techno, jazz, etc.) if the sub is moving substantially at high volume (let's say around 22 on the head it should be moving in and out over 1/2" each way) then that's alright... if it's a lot less, then something is wrong...

also, mine got noticably louder over time.


here's my thoughts on a good way to setup your system as a starter to work from:

connect front pre-amp outs to amp's front channel
connect sub pre-amp outs to amps sub channel
bass set to 0
treble set to 0
MX off
time delay set to 12 (1.2 ms) on left
sub channel on and output set to +15
high pass frequency on head unit set to off
low pass frequency on head unit set to off
amp's highs high pass frequency set to 80hz (-12db slope).
amp's sub low pass frequency set to 80hz (-12 db slope).

see how that works out. based on what we talked about before, i'm afraid you've got settings that may be hurting your sub's output. i seem to remember you saying you had your bass down a lot and the crossovers set quite high... i'd like to clear that up first.



now i should also mention one thing that i experienced w/ this sub, is that it just didn't seem loud enough. however, mine is a very unusual case... i am also pumping 110 Wrms rated, and more likely 150Wrms to my (very) sensitive fronts and 300 Wrms rated and 450 Wrms actual to the sub. so, i'm blowing my sub away w/ my front volume. (i have a LOT more power going to my fronts than you do...)

my 2 solutions that i tried to fix this were as follows...

1st: i reduced the gain to my fronts and balanced them down to the sub. this sounds great, but i miss my volume (i do lose some).

2nd: i cross my sub over at a 60hz range and run my front speakers full range. they fade off in frequency response around 60 hz anyway, so the sub takes over, but they still provide some lower fill.

i would recommend you not go these paths just yet... let's determine if you have any other minor issues before we pursue other options.

edited for clarity and additional thoughts

 

The crossovers, Im not sure about. The first installer who looked at it said he had no idea how to tune it, the other guy came over and adjusted the gains, and installed the two crossover chips, high and low. The remaining tuning must be done by through moving jumpers around on the board. I dont know what the numbers mean, so I cant do it.

There are seperate RCAs from the headunit.

The sub is running off the mono channel.

I am testing with rap. (Should have ample bass)

HU settings- treble is +5, bass is -7, sub is +15.
Amp settings- front/rear gain 50%, mono gain 100%.

I do not have test tones.

The sub does have movement, however, I do not think it has 1/2 an inch worths of excursion. I listened to it again and I could barely hear it with the trunk closed.

WLaurent suggested that they may have wired it to an 8ohm load. So I will check that, however I hear this thing is tricky to mount, so is there anything I should worry about or watch for while removing it?
gmoore

 

I took the sub out of the box to find it was wired to an 8ohm load. Idiots. Sometimes I feel I could do the work better myself. Ill let you know about my next problem. Thanks again.
gmoore

 

Ya know what just occured to me? The sub channel might not be 2 ohm stable. If its not, I just blew another 256 on an amp that isnt strong enough. I cant believe I didnt think of that. Can you clarify if it is stable, or isnt? :crosses fingers:
gmoore

 

Turns out it is 2 ohm stable, so I went ahead and wired it into parrellel, and reinstalled it. It doesnt seem any louder now than it was at an 8 ohm load. I dunno whats goin on, I give up, Im just gonna have them look at it.
gmoore

 

glad to hear that the sub was an easy fix... and yes, i took care of you and made sure that the sub channel was 2 ohm stable...

i think the main problem is that you've got your bass turned down to -7 ! that's very low... if you dial the bass down like that, it removes the signal from both the fronts AND the sub channel.
i'm not sure what percentage of the total that represents, but try dialing that up to something closer to 0 and see if that doesn't help.

also, i would move the amp gain on the sub channel to somewhere closer to 75% after you've turned the bass up and before you crank it up.

right now, it sounds like your system is good to go, but just setup really wrong. i wish you lived closer.

 

btw - are you familiar with what crossovers do?

i'm guessing you have the bass turned way down and the treble way up for some reason... and the reason i would suspect is probably covered by the crossover.

please -- try the bass at 0.

 

I turned up the bass, it may have helped slightly, but still not enough. Im looking at the installers reference and there is a series of jumpers that allow adjustability. I think we may find our solution within these. I do not understand what the terminology is, so you will have to translate. First there is an input sensitivity adjustment. The jumper is at +10 DB from the factor, can be taken up to +20 DB and down to -20 DB. There are also output gain pots, and jumpers. The pots being the simple turning adjustments, while the jumpers can be moved from +20 DB to -20 DB.

It says I may encounter clipping with the output gain adjustments, and to back off if I do. This is the problem I am having when I pull up the bass. When I increase the volume and bass it becomes distorted, and clips. Thats why I turned it down in the first place.

The input sensitivity is Japanese to me, however it seems that for the output sensitivity I should bump the mono to +20 DB, with the gain pot all the way up.

As an extra step, I will adjust the crossovers to the speakers, and I suppose I could even drop the output gains on the mids to +/- 0 DB if this would allow me to keep the bass turned up.

Does that make sense? What should I adjust to where?
gmoore