New to car audio, please help with a few issues

[audioholic 5,000+ posts]

Only running one coil of a multi-coil speaker will alter the t/s parameters of the speaker, and is not recommended unless you really know what you are doing (and the manufacturer provides t/s specs for single coil operation).

When an amplifier is bridged, the impedance the amplifier sees is split between the two channels. That is why a 2ohm stable amp is only stable to 4ohms in bridged mode, because each channel will see half that load (4ohms / 2 = 2ohms to each channel).

 

[hispls 5,000+ posts]

Only running one coil of a multi-coil speaker will alter the t/s parameters of the speaker, and is not recommended unless you really know what you are doing (and the manufacturer provides t/s specs for single coil operation).
When an amplifier is bridged, the impedance the amplifier sees is split between the two channels. That is why a 2ohm stable amp is only stable to 4ohms in bridged mode, because each channel will see half that load (4ohms / 2 = 2ohms to each channel).

^^^^^^

This.

OP, you need a bigger or more efficient amp. Half an hour driving A/B amp hard (particularly at low impedance) will always have them super hot. Full range class D has come far enough that if you have some money to invest in quality you won't have this problem

 

[MillerSHO 10+ year member]

Man, you guys have taught me so much in this thread.

Kinda too bad I didn't know that this combo wouldn't work out before I bought it but then again I got the amp, sub and enclosure for $150 so I can't complain and I'm thankful that you guys uncovered why it's not stable at high volumes for extended lengths of time.

My final few questions will be regarding a new amp setup and if you guys take your time to respond awesome but if you don't I understand, I'm probably starting to get annoyings but any help I;m thankful for, I just enjoy learning about this stuff:

1. Would the alpine MRP-M500 class D mono amp be a good match for the Type S sub?

(Says the amp is 2ohm stable bridged and will max my sub out at 500rms)

2. What do I need to run two amps? I assume a distribution block will tap into the current power wire and then the two amps will tap into the distro box? Will I need a capacitor on one or both amps?

3. Finally, what is the best way to setup my current F450 amp if I went with a dedicated sub amp? Would I just keep my High Energy's hook up on channels 1 and 2 the same way they are now and then run my 6x9's on channels 3 and 4?

Or is there a way to run my High Energy's on all 4 channels, getting the full power of the amp to those speakers or would that drop the ohms to 2 and make the F450 amp unstable again?

 

[audioholic 5,000+ posts]

Man, you guys have taught me so much in this thread.
Kinda too bad I didn't know that this combo wouldn't work out before I bought it but then again I got the amp, sub and enclosure for $150 so I can't complain and I'm thankful that you guys uncovered why it's not stable at high volumes for extended lengths of time.

My final few questions will be regarding a new amp setup and if you guys take your time to respond awesome but if you don't I understand, I'm probably starting to get annoyings but any help I;m thankful for, I just enjoy learning about this stuff:

1. Would the alpine MRP-M500 class D mono amp be a good match for the Type S sub?

(Says the amp is 2ohm stable bridged and will max my sub out at 500rms)

2. What do I need to run two amps? I assume a distribution block will tap into the current power wire and then the two amps will tap into the distro box? Will I need a capacitor on one or both amps?

3. Finally, what is the best way to setup my current F450 amp if I went with a dedicated sub amp? Would I just keep my High Energy's hook up on channels 1 and 2 the same way they are now and then run my 6x9's on channels 3 and 4?

Or is there a way to run my High Energy's on all 4 channels, getting the full power of the amp to those speakers or would that drop the ohms to 2 and make the F450 amp unstable again?

1. Going by the specs, yes that amp will match your type S fine.

2. To run those two amps, you'll need a run of 4awg wire to a distro block, then 8awg wires from the distro to each amp. You do not need, or want to waste money on, caps.

3. Yes, you can hook up all 4 full range speakers to your current amp. Id recommend gaining the rears down a bit so they do not overpower the front stage though. You could also bridge channels 1 and 2 to the left front speakers, and 3 and 4 to the right front speakers (or vice versa). Im too lazy to look up the specs on your Hertz speakers, but Im going to guess this would be more power than they are rated for, in which case you would set the gains artificially low to limit the amplifier's output to them (which would also improve sound quality *somewhat*). What works best for you is subjective, as some people prefer to have 4 full range speakers, 2 in front and 2 in the rear, while I prefer a solid front stage with little or no rear speaker output (and only then in the form of rear fill). The size of your vehicle's interior, and if you plan on entertaining rear passengers often, also is a factor.

You aren't getting annoying at all. This forum is meant to have people share car audio information, so ask any questions you want.

 

[MillerSHO 10+ year member]

1. Excellent, probably get that ordered up next week unless you guys feels there's a better solution for a sub $200 mono amp. (At $900 with the build currently, was hoping to keep it as close to $1k as I could so as much as I'd like to spend tons of money on high end stuff I have to keep within a budget)

2. Thanks for this info, that makes perfect sense.

3. You bring up some really good points. In the end I'm more of a front sound stage kinda person so leaving the 6x9's on the HU amp as rear fill would be ideal for me but then again I feel weird about wasting some of the amps overall power if I dedicate the F450 to the fronts.

Then again these AB amps get hot and I do listen for extended periods so maybe running at 75% wouldn't be a bad thing. (Hertz 165's are rated @ 150rms, the F450 amp bridged to 2 channels would be 200x2 RMS).

 

[audioholic 5,000+ posts]

Many SQ guys intentionally buy oversized amplifiers and gain them down. This means the amp will run at a lower than maximum output in all situations (even at full tilt) so SQ and damping will be improved. You may or may not have the ears to hear the difference this would make, but it would give you some comfort when considering losing some output potential of the amplifier.

If you really are a front stage guy, consider setting up the rear speakers as rearfill. This means their output will be attenuated as compared to the fronts, and bandpassed (500hz to 5khz or so). This will minimize their impact on the front stage. You may have trouble bandpassing them though if you only run them off the h/u's amplifier. Just some more food for thought.

 

[MillerSHO 10+ year member]

OK I got real hyper and already ordered everything up to make the change to two amps. Let me know how I did.

Amp= Alpine MRX-M50

Sub= JL W3 12" 2ohm

 

[audiobaun 5,000+ posts]

OK I got real hyper and already ordered everything up to make the change to two amps. Let me know how I did.
Amp= Alpine MRX-M50

Sub= JL W3 12" 2ohm

Not a bad little amp by any means to push either sub you have chosen,,it should be around 50-70% efficient with stock electrical..The JL sub will be a nice SQ sub woofer in a well made enclosure by specs..A good distro block, and a small amount of wiring and you should be fine..Even the JBL sub you have will be just fine with that amp as well..my 0.02cents

 

[dragnix 5,000+ posts]

I prefer to buy used and get more for my money, but that's just my cheap self lol

 

[MillerSHO 10+ year member]

Not a bad little amp by any means to push either sub you have chosen,,it should be around 50-70% efficient with stock electrical..The JL sub will be a nice SQ sub woofer in a well made enclosure by specs..A good distro block, and a small amount of wiring and you should be fine..Even the JBL sub you have will be just fine with that amp as well..my 0.02cents

That's great news.

On a lighter note I hooked up the sub to the existing amp and man I can't believe how much harder it hits vs. the 10" type S in a sealed box with the same amp.

The amp cut out way faster this time with the 12" JL plugged in so I find it weird that a different sub can draw more power even though the type S was still wanting more power then I was giving it.

 

[MillerSHO 10+ year member]

I prefer to buy used and get more for my money, but that's just my cheap self lol

Minus the stuff I bought today and the Kenwood HU everything in my setup is used.

The 4 channel amp, amp wiring kit, type S 10", all speaker wiring and Hertz Hi Energy 165's were all used.

Going to install the type S 10" with sealed box in my Wife's Tahoe, I've been slowly upgrading her system and nothing has gone to waste.

 

[MillerSHO 10+ year member]

Got everything installed. It sounds amazing(to me at least).

The F450 amp still gets hot after an hour of working it hard but it doesnt cut out,

which was what promoted all of this.

The sub amp is only at the halfway point (nom setting) and the sub setting on the HU is 7 out of 15 and it hits so clean. I really love knowing I have head room to play with also on both amps, just gives me piece of mind.

At some point I'll prob replace the F450 and go with a newer 2 channel amp to try to take the hertz to the next level. Fwiw adding the full 150rms

to the hertz made them only slightly louder but they have way more bass to them vs. when they had 75watts rms.

Thanks again everyone.

 

[audiobaun 5,000+ posts]

Got everything installed. It sounds amazing(to me at least).
The F450 amp still gets hot after an hour of working it hard but it doesnt cut out,

which was what promoted all of this.

The sub amp is only at the halfway point (nom setting) and the sub setting on the HU is 7 out of 15 and it hits so clean. I really love knowing I have head room to play with also on both amps, just gives me piece of mind.

At some point I'll prob replace the F450 and go with a newer 2 channel amp to try to take the hertz to the next level. Fwiw adding the full 150rms

to the hertz made them only slightly louder but they have way more bass to them vs. when they had 75watts rms.

Thanks again everyone.

Man..Nice outcome of everything..Good to hear:santa:

 

[MillerSHO 10+ year member]

Man..Nice outcome of everything..Good to hear:santa:

Thanks.

But now I have another issue, I need to Dynamat various areas of the car to get rid of rattles.

It never ends does it? //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[gckless 5,000+ posts]

Thanks.
But now I have another issue, I need to Dynamat various areas of the car to get rid of rattles.

It never ends does it? //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

It. Never. Ends.