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Brasscatz
03-04-2013, 06:51 PM
Here's one for the Audio gurus. I had an OLD amp, probably at least 10 years old in my Jeep powering a 10" BOSS Sub. I had it bridged since I only had the one sub. Sound was fine, no real issues other than certain tones of bass would not come through well at all. I came across a new amp that was a 4 channel amp. Hooked it up and man what a difference! All bass sounded good, maybe even a little too much for my needs.

Drove to work today and all was well until I got almost to work... no sub. I checked and the amp was VERY hot. I let it cool down, and still no sub. Even after work, no sub. Checked all the wires, all were good. Checked fuses - good. The power light on the amp still comes on, but no sound from the sub. One thing I did try was putting my hand on the sub cone and press a little bit and I could feel SLIGHT vibrations with the music. Unhooked the speaker wire and vibrations gone.

I know that my issue probably stems from not having the correct settings on the amp, not knowing the ohms, not knowing how to set up the sub connections inside for ohm ratings, etc... Am I on the right track? Is my sub blown now?

Brasscatz
03-04-2013, 09:01 PM
Yeeeeep. Pretty sure my sub is blown. Hooked up the 300w sub I got with that amp and it works. My existing 1200w sub... doesn't. I don't know if I've got things wired up correctly or not. I'd hate to blow another sub

XJ Wheeler
03-04-2013, 10:13 PM
Yeeeeep. Pretty sure my sub is blown. Hooked up the 300w sub I got with that amp and it works. My existing 1200w sub... doesn't. I don't know if I've got things wired up correctly or not. I'd hate to blow another sub

That sucks, bud. Hope it wasn't much $. If i was back home i have a 10" mtx i could let go. At least ya still got the other one.

Brasscatz
03-05-2013, 12:16 AM
Thanks bro. It was a Christmas gift from my mother-in-law in 2011. Boss sub from walmart ;) I just hope this other one doesn't blow on me tomorrow...

TimmyTXJ
03-05-2013, 11:12 AM
Here's one for the Audio gurus. I had an OLD amp, probably at least 10 years old in my Jeep powering a 10" BOSS Sub. I had it bridged since I only had the one sub. Sound was fine, no real issues other than certain tones of bass would not come through well at all. I came across a new amp that was a 4 channel amp. Hooked it up and man what a difference! All bass sounded good, maybe even a little too much for my needs.

Drove to work today and all was well until I got almost to work... no sub. I checked and the amp was VERY hot. I let it cool down, and still no sub. Even after work, no sub. Checked all the wires, all were good. Checked fuses - good. The power light on the amp still comes on, but no sound from the sub. One thing I did try was putting my hand on the sub cone and press a little bit and I could feel SLIGHT vibrations with the music. Unhooked the speaker wire and vibrations gone.

I know that my issue probably stems from not having the correct settings on the amp, not knowing the ohms, not knowing how to set up the sub connections inside for ohm ratings, etc... Am I on the right track? Is my sub blown now?

Jim,
I'm not an audio expert but it sounds like you could have an impedance issue. Double check to make sure your amp has a lower impedance rating than your sub. ie amp@4 ohms, sub@8 ohms = no problem, amp@4 ohms, sub@4 ohms = no problem, amp@8 ohms, sub@4 ohms = overheated amp and possibly a damaged sub.

NW99XJ
03-05-2013, 02:06 PM
One other thing to take into consideration, other than the maximum impedance handling of the amp....is that when you bridge a channel of the amp, regardless of how many speakers you have, the final load the amp sees is actually HALF that of the static resistance of the speaker(s).....
FOR EXAMPLE:
(note: the lower the number when measuring resistance -ohms- the closer you are to a dead short)
if you have two 4ohm subs.....and wire them in parallel:
+ of one to + of the other, and - of one to - of the other.
(this too halves the overall impedance)...the static impedance is 2ohms.
....once bridged...the amp actually sees 1 ohm.
Most amps cannot sustain 1 ohm bridged load.


Lets take the same set up, but wire the subs differently....
two 4ohm subs wired in series:
+ of one to the - of the other and the remaining + from one and - of the other go to the amp.
(this will double the overall resistance)...the static resistance is 8 ohms.
....once bridged...the amp actually sees 4 ohms.
Most amps can easily handle a 4 ohm bridged load.

That being said...... it is common to take a 4ch amp and run all the door speakers off of just the front channel. Wiring each side in parallel.
Front left and rear left each share the - & +... and we do the same with the right side.
Since most car audio speakers are 4ohm, this creates a 2ohm load PER SIDE.
Since we still want to retian stereo imaging, at least from left to right, there is no need to the bridge the 4 sets of speakers...instead we run each side at a 2 ohm STEREO load at the amp.
Most maps can sustain a 2 ohm stereo load.

The remaining channel (rear) of this 4ch amp is then reserved to run a sub(s).
As long as the amp has built in crossovers (most amps nowadays do) then you have the ability to really dial in the frequency levels going to the different sets of speakers.
Usually a high pass cut off for the subs, and either a full range signal (if your running component speakers) or a low pass cut-off for full range or co-axial speakers.

In your case Brazzcats, you may have had a 2 ohm sub, or perhaps a dual voice coil sub, and had it hooked up to the amp wrong.
OR....you didnt have the crossover set right on the amp, and were trying to push a full range signal thru the sub.

The larger diameter speakers (subs) cannot recreate the higher frequencies as easily as smaller diameter speakers. Subs are meant to move much slower, creating the lower frequencies associated with "bass"....forcing them to move fast enough to try and create higher frequencies will most often burn up the voice coil faster than pushing too much wattage thru them.

Brasscatz
03-05-2013, 07:47 PM
Thanks Tim and Josh. I have to admit, I don't understand most of that impedance and ohm stuff LOL. I will have to look at my stuff and post pics up here so you can help me out. I did understand what you meant in the last paragraph, and I've been playing with the settings on the amp. Unfortunately, I don't have a manual for the amp, I'll have to take a pic of the stuff and let you help me out on that. I'm actually kinda pissed that I blew that sub, and I bet you are correct on the settings putting full range through it. I don't know if I have the correct settings now or not.

The current setup I have is solely for the sub. The speakers are just hooked up straight to the head unit, and amp to the sub. I'll get some pictures up of my equipment as soon as I can. Thanks again for the help guys!

Brasscatz
03-06-2013, 09:40 AM
http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1379_zpsb75a674b.jpg

http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1380_zps6e71362b.jpg

http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1381_zpsf45da721.jpg

http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1377_zpsa7fe19e5.jpg

http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1376_zps569c30cc.jpg

http://i356.photobucket.com/albums/oo7/thestalliontruck/Random/IMAG1375_zps61c52cb4.jpg

Brasscatz
03-06-2013, 09:47 AM
I'm guessing the settings on the left side for the front don't matter because I don't have anything wired to the front channels. Hopefully these pics help. The sub appears to be wired with positive from one side and negative from the other to the amp. Then the other positive and negative wired together... If I remember correctly from taking the sub out of its enclosure the other night.

NW99XJ
03-08-2013, 09:56 AM
Ok Jim,
First let me say that's an awesome amp.
Phoenix Gold is a great brand. Top quality components, and great performing products.
as far as the way you have it hooked up, it appears to be fine, (without seeing the entirety of the install.)
The settings, I think may be just a tad off.
The metal "dial" on the right side (the one with the screw driver slot) , is going to be the filter, or crossover selection.
LP = Low Pass (only low frequencies will be heard)
HP = High Pass (only high frequencies will be heard)
BP = Band Pass (selectable frequencies - low and high cut off - middle range)
BY = Bypass (all frequencies heard)

In the pic above it appears to be in the "bypass" mode....meaning the crossover is bypassed....which in turn means that you were indeed sending full range signal to the sub.

It wont matter WHICH one of the "LP" you adjust the dial to. It just needs to be on one of them.
The reason for more than one is for different configurations of the signal going OUT of the amp thru the "AUX OUTPUT"...this is for daisy-chaining amplifiers together.
Obviously this wont apply to you at this point, so I wouldn't worry about it.

The three dials on the far right are going to be for fine tuning.
The SENS is basically the gain.....this will determine how much volume is going to be produced.
The BASS is going to be a separate gain unto itself.
This will amplify whatever frequency is selected by the FREQ knob.
That knob will determine at what point the crossover will cut off the frequency range.
The more to the left you turn it, the more only the lowest frequencies will be heard.
The more to the right you go, the more you start to introduce higher frequencies.
In this case, since you will have the Low Pass filter engaged, .....the high frequencies will just be the upper end of the bass spectrum. More "snap" to the kick drum so to speak, and not all just the bump/boom.

Start with the SENS knob, turned all the way down.
Put on a song typical of the type of music that you listen to most, and bring the volume up on the deck.
Adjust the bass on the stereo to zero, or below.
Then go to the amp and start to bring the SENS knob up to a level that gives you a nice balance to the rest of the volume level.
Play around with the BASS and FREQ knobs until you get a sound that you're looking for.

Hope this helps!

4.3LXJ
03-08-2013, 10:26 AM
It is good we have someone on here that understands this stuff. All Greek to me

Brasscatz
03-08-2013, 07:38 PM
Ok Jim,
First let me say that's an awesome amp.
Phoenix Gold is a great brand. Top quality components, and great performing products.
as far as the way you have it hooked up, it appears to be fine, (without seeing the entirety of the install.)
The settings, I think may be just a tad off.
The metal "dial" on the right side (the one with the screw driver slot) , is going to be the filter, or crossover selection.
LP = Low Pass (only low frequencies will be heard)
HP = High Pass (only high frequencies will be heard)
BP = Band Pass (selectable frequencies - low and high cut off - middle range)
BY = Bypass (all frequencies heard)

In the pic above it appears to be in the "bypass" mode....meaning the crossover is bypassed....which in turn means that you were indeed sending full range signal to the sub.

It wont matter WHICH one of the "LP" you adjust the dial to. It just needs to be on one of them.
The reason for more than one is for different configurations of the signal going OUT of the amp thru the "AUX OUTPUT"...this is for daisy-chaining amplifiers together.
Obviously this wont apply to you at this point, so I wouldn't worry about it.

The three dials on the far right are going to be for fine tuning.
The SENS is basically the gain.....this will determine how much volume is going to be produced.
The BASS is going to be a separate gain unto itself.
This will amplify whatever frequency is selected by the FREQ knob.
That knob will determine at what point the crossover will cut off the frequency range.
The more to the left you turn it, the more only the lowest frequencies will be heard.
The more to the right you go, the more you start to introduce higher frequencies.
In this case, since you will have the Low Pass filter engaged, .....the high frequencies will just be the upper end of the bass spectrum. More "snap" to the kick drum so to speak, and not all just the bump/boom.

Start with the SENS knob, turned all the way down.
Put on a song typical of the type of music that you listen to most, and bring the volume up on the deck.
Adjust the bass on the stereo to zero, or below.
Then go to the amp and start to bring the SENS knob up to a level that gives you a nice balance to the rest of the volume level.
Play around with the BASS and FREQ knobs until you get a sound that you're looking for.

Hope this helps!

That does actually help more than you know, Josh. THANK YOU!!! I have been listening to my mp3 player with earbuds in my Jeep the last few days fearing blowing this other sub until I heard back LOL! I don't remember what the setting was before on that knob, but I've messed with it since then, but I know it wasn't on the LP setting though!

I'm guessing that I only need worry about the LP on the top of that dial and not what the bottom says, right?

I'm glad this is a good amp. Can't beat free, right? I love it when cars come into my dealership with stuff in them and I get to raid them sometimes for goodies lol. The amp I had was at least 10 years old, and not very good. I'm definitely not looking to rattle my windows, just to be able to feel and hear the music a little bit. It is, after all, a Jeep and not a dance club ;) So the way I described the sub wiring sounds to be correct? I don't suppose I'll be able to warranty that other sub that I blew, huh? lol, oh well. Wishful thinking :D

Thanks again Josh!

Brasscatz
03-08-2013, 07:40 PM
It is good we have someone on here that understands this stuff. All Greek to me

Same here, buddy. It's one of those things that I like the end result, but don't have the attention span to learn all that goes in it. Like when I taught myself to play the guitar... I don't read sheet music in treble clef (I'm a trombone player and read bass clef), I taught myself to read guitar "tabs" to play.

4x4Dalton
03-10-2013, 11:45 PM
Same here, buddy. It's one of those things that I like the end result, but don't have the attention span to learn all that goes in it. Like when I taught myself to play the guitar... I don't read sheet music in treble clef (I'm a trombone player and read bass clef), I taught myself to read guitar "tabs" to play.

Good. Later on you can help me hook up a amp I have in my XJ :D

Brasscatz
03-11-2013, 12:02 AM
Good. Later on you can help me hook up a amp I have in my XJ :D

lol, no problem!

4x4Dalton
03-11-2013, 12:03 AM
Sweet

NW99XJ
03-11-2013, 08:57 AM
I'm guessing that I only need worry about the LP on the top of that dial and not what the bottom says, right?
CORRECT!
The other side of the dial is just for the "pass thru" or to control the AUX output. In your case you wont have to worry about that.


I'm glad this is a good amp. Can't beat free, right? I love it when cars come into my dealership with stuff in them and I get to raid them sometimes for goodies lol.
You dont know how lucky you are! When that amp first hit the market it was easily a $300-400 unit.


So the way I described the sub wiring sounds to be correct? I don't suppose I'll be able to warranty that other sub that I blew, huh? lol, oh well. Wishful thinking :D

Thanks again Josh!
I don't know about the warranty part, but yea it sounds like you have it wired up right.
Maybe throw some pictures up here so I can double check?
Also, if you have a multi-meter, you can double check yourself on the resistance (ohms) that you'll be seeing at the amp., Just make sure you're not testing it with it hooked up to the amp. Otherwise you'll be trying to measure the resistance of the circuitry too.
Glad to help out man.

Mudderoy
03-12-2013, 11:34 PM
Jim,
I'm not an audio expert but it sounds like you could have an impedance issue. Double check to make sure your amp has a lower impedance rating than your sub. ie amp@4 ohms, sub@8 ohms = no problem, amp@4 ohms, sub@4 ohms = no problem, amp@8 ohms, sub@4 ohms = overheated amp and possibly a damaged sub.

That's what I was thinking. The speaker acts much like an antenna connected to a RF power amp. If the speaker, or the cable is reflecting the power back to the amp, it's going to get hot and then the final transistors are going to die of heat.