I originally posted under "JL Audio or Hertz? Opinion wanted" - I need to ask one direct question from Experts in the Car Audio field.

As stated in other post - I had a new system installed in my 2008 Non-Bose vette. I have ONE major concern:

I went with the following system:

1 - Kenwood KIV-BT900 (I am very happy with this - LARGE 3" LCD screen - Very clear - Never really listen to CDs - Just Radio.)

2 - Audison SR4 (I asked if this amp was too small for the 10" - He said that it is in the Lower end on the watts - But it is "Clean" power.. Whatever... Thats why he is giving me 30 days to try the amp...)

3- Hertz ESK 165.4

4 - Hertz ES 250 D.4

First: I think the box they built is TOO small for the Hertz 10" Sub. The bass does NOT sound as good as I expected. I attached pics below of sub. My plan is to take the speaker out - Measure out 6.5 cubic feet of sand - pour the sand in the empty sub shell and see how much sand is left over (I expect quite a bit) - Then, vacuum all the sand out.

Second: (Also question about BASS) The amp is pushing 190 watts to the sub - And, the sub is rated for 250 continuous watts. (The door speakers are rated for 100 ciontinuous and the amp is pushing 60 watts). So, the Sub is underpowered. IS THIS A REASON WHY MY BASS SOUNDS NOT AS GOOD? PLUS, I LOSE ALOT OF BASS (Hardly any) at LOWER volumes.

So, my question is:

Is it a combination of a under-powered amp AND too small bass box? Or, is it more of one over the other?

The shop says that this Audison is severly "Underrated" when it comes to watts and is suppossedly "Clean" power.

I am going to make them build me a bigger box - I mean, if the spec on the 10" says 6.5 Cubic Ft. - Then, it should be 6.5 Cubic Ft - Right?

But, Should I have them replace the amp with a larger one? Will it help the Bass on the LOW end of the volume?

Thank you VERY much for your help - I am a bit stressed over this as I expected the shop (Good Reputation for 20 years) to deliver a bit better bass....

Marc

 

6.5 cubic feet? That can't be right. That would pretty much be your entire hatch.

Probably .65 cubic feet... And it's hard to say if that box is .65 or not.

Also this sub is up-firing which generally produces less than stellar results in a Corvette. could be the crossover point, too.

Or maybe it just needs the phase reversed. Reversing the phase can make your sub take a 180' turn in performance... pun intended.

Lights probably just aren't hooked up.


The SR4 is about 200watts right? I would put at leats 300 watts on that sub myself, but I like headroom.

Even if underrated, I doubt it makes more than 220-230 watts. Pretty sure Audison amps come with a birth sheet, that should tell you for certain.



PS -
Subwoofers pretty much always play louder than the rest of your system. The problem is they also compete against road noise and there's also the little fact that the human ear isn't as sensitive in those frequencies.

If the sub was playing a tone at 90db at 60hz, you wouldn't really be that impressed. If your tweeter was playing a tone at 6khz at 90db, you would be jamming your fingers in your ears and running for cover.

Some head units boost the subwoofer at lower frequencies to combat both issues, but most do not.

The trick here is to set the gains on your front speakers normally (at 3/4 volume)
Set the gain on your subwoofer to 1/2 or even 3/8 volume.

You probably will never listen to your system at 3/4 on the head unit (Full amp volume) because it will hurt your ears (and also **** up your hearing.)

Now your subwoofer is proportionally louder with the rest of your system and you will have more bass at lower volume levels.

If you ever DO crank your system fully, use your sub-specific volume control (almost all head units have this) and turn it down 25% before turning your system up the full way.


In conclusion,

This is a 10" sub with only 200 watts on it. It's also a Hertz sub so it's not built with boom cars in mind. It's built for sound quality which means integration with the rest of your sound and not standing out like a sore thumb.

I'm running a 12" sub @ 370 watts in my system and you wouldn't know it's there unless I turned it off - this is the goal of a sound-quality oriented install. Not to say I didn't go through a phase with 1200 watts on a massive 12" sub that caused the panels of the car to flex...


(PS, I looked up your sub. 9mm of xmax isn't exactly a kidney-puncher, but it looks like a great sub for sound quality. It performs well in .6-.8 cubic feet. With less power, the bigger box is better. 200 watts in .8 would be better. If you ran ~300-400 watts it would be safer to get closer to the .6 mark.)

 

Thanks alot for the advise.

I will have them increase the box size. I will also see if they can angle the sub any - They were supposed to do this but said they couldn't get the sub out if they did - I think thye just did the easiest.

I will also get a quote to upgrade the amp to a stronger one. If that 10" is supossed to run at optimal performance at +/-300 wats - Then, 190 is too small.

 

Keep in mind, even with a perfectly ideal box and plenty of power that sub is not going to give you chest-thumping bass.

Before cutting/rebuilding/etc I would first highly suggest trying setting the gains as I mentioned and also reversing the sub's phase.

Also check the crossover. 80hz is generally good for a sub.

 

Audison amps "underrated"? Thats the first time I heard such a thing. Its not like underrated car HP to keep insurance rates down on muscle cars. Theres no possible reason to underrate amp wattage, I say they're full of crap just trying to snow job you. On the contrary, many amps are given higher ratings to sell more product.

As I mentioned in the other thread you need a more powerful amp. 60w to your components is equally off base and your midranges are suffering. You also want to have an amp which is capable of more power than required(head room as mentioned). Any shop should learn this in Car stereo 101 class.

As for the enclosure, its hard to tell but it looks small to my eye in the pic. My JL Stealthbox has a 10W3 and is compareble in power to yours and the JL enclosure seems bigger to me. I have it powered with a JL 300/2v2 and it sounds great SQ wise and can thump pretty good when I turn it up. I went with JL to avoid issues of some schmo calling himself an "audio expert" making a box not knowing what hes doing. Heres a pic of mine installed if it can help you get an idea of the size.

 

Thanks everyone.

I agree NYC6 - I should have went with JL Audio Stealth Box. I learned my lesson there. Pay for what is done and mass-produced as it had to be tested....

I do want them to gain air space with my box - I never wanted it to point straight-up either - But, at this point I guess THAT is not the biggest conern I have.

I will probably have him go UP in Amp size IN EXCHANGE for the damage that they did to my plastic fuse box cover and passenger side plastic cover. If not, then they can pay $400-$500 to have my fuse box pulled and replaced and a new valve cover.... I can cover the fuse box side - And, the valve cover I can get ALMOST back to perfect...

And, they are going to rest all of the gains, etc...

I also agree that my MIDS ARE suffering after you said it. So, bigger amp with "Head-Room"

I will let you know on Monday how it all goes.

I have a more pressing issue that the horn will NOT shut off...

 

Cheater amps aside - It's not uncommon for quality amps to produce more power than rated. Its extremely rare for that to be more than 10%, and is usually more around 2-5%.

 

McIntosh Labs amps are always under rated. It's really not uncommon at all in higher end stuff. Even being an SRx series amp,Audison is still high quality. That being said,an amp rated at 200 is not going to be putting out 350. As Kale said,that sub is not designed to kick you in the chest. More so to bring the low end in kinda subtle.

Personally I would be going up in amp size and probably looking at a different sub if I wanted thump.

 

Good luck, looking forward to see how you make out.

 

Well, it's a new Monday and a New week.

Got up and told GOD that this week was going to be GREAT no matter what.

Went to the donut store and got a dozen donuts for the stereo shop. The owner ate one so I feel that there is no resentment there - However, the installer did NOT.... Hmmmmm. Oh Well.

The stero shop is making everything right. They are replaceing the scratched head unit. They are increasing the size of the sub box, they are putting black vinyl finish in the door panels so that you can;'t see the silver deadening material through the grills, etc....

AND, GET THIS: He is UPGRADING my AUDISON 4 channel amp with the next size AUDSION 5 Channle amp - FOR FREE !!!

Now, instead of having 190 watts to my sub that takes 250 RMS - I will get around 250-300 RMS. AND, instead of getting 60 watts to each door speaker - I will get 75 watts (The door speakers have 90 RMS rating).

So, my NEW question is this:

In light of the new AUDISON 5 channel amp 4x75 and 1 x 300:

1 - WOULD YOU Bridge the 2 75's together for JUST the fronts to get the FULL 100 Watts that the door speakers are rated for -

2 - OR, would you replace the rear speakers now and amplify ALL 4 speakers with 75 watts??? (Right now the rears are JUST run off of the Kenwood HU.)

I want more mid and lows when the volume is turned down. Which of the above will give me the best setup?

Thanks,

Marc

 

Id just put the power on the doors. The rear speakers don't make too much of an effect on how it sounds, if anything they're adding coloration and cancelation. I know alot of Sound Quality car audio competitors who do not even run rear speakers because of those issues.

Its good they gave you an upgrade to a bigger amp, at least you made out on that one. Hertz isn't really a great brand of sub if you wanna "crank" it. Its just mechanically incapable of doing so given it's low xmax and low thermal rating. Probably a better choice would of been a FI Q , RE Sx , anything along those lines.

And im glad they're redoing that enclosure, not only is it hidious but its clearly the wrong size. That installer should get a swift kick in the *** for that one. Also, consider going with a ported enclosure next time for optimal use of the small amount of power you're running. It takes way more power to get a sealed enclosure as loud as a ported, yet you can put more power to a sealed enclosure. Just something to keep in mind.

 

OK - I'll put the full RMS to the doors - Do you think that will also give me MORE Mid-Bass at lower volumes? Or at any volume?
I am still learning some of this stuff and don't know what makes the speaker "Better" with more power??..?? Right now I have 60 going to both fronts - So, If I have them put the full 100 RMS to the front 6-1/2's and tweeter - Does that mean it will be almost twice as loud? Or, does it just mean that it will be "Clearer"?

I hope it will make the system "Louder" at lower volumes and also give me more bass at lower volumes.

Right now - I have to turn the KIVBT900 up to about 16-18 for me to start enjoying the bass and volume. But, I can only go up to 28 (Stereo shop said that was the max because at 30 the amp cuts out.)

So, really volume 1-16 is useless because it is too much Highs and not enough bass or mids to enjoy the stereo at lower volumes.

Thanks, I didn't want to have to learn this much - But, since I learned this much - Might as well understand what I have....

Thanks,

Marc

 

Midbass comes from tuning, balancing, and install more than it does from power alone.

Keep in mind it's going to scale with the rest of the system. You aren't going to magically amplify one portion of the spectrum and not the other. Your mids and highs will be relatively louder too (but not dramatically.)

More power will allow you greater volumes with less distortion. I am doubtful if it will give you any low volume midbass.

 

Im not into all that competiition talk of "front sound stage" only. All top shelf cars today have multi speaker systems of 6-12 and more speakers in their cabins. Rear fill works for me and anyone whos sat in my Vette. My JL-C5-650 components get 150w each and the JL XR-525's in the rears are getting 75w each of clean JL amp power. You have good speakers out back, power em well. Keep the gain up more on the fronts and will will sound fantastic! With the enlarged box and more wattage fed to it you will have a system that will sound stellar.

 

usually fitted with low quality drivers too. Should I use Bose as an example

 

Mass production products are built with the mass consumer in mind, not niche group of "car audiophiles."

Can you imagine if Lexus released a car with front speakers only? It could sound like the voice of angels carried on the back of a magical unicorn and reviewers would destroy it in the papers because quantity is king.

 

Bose in the Corvette case would be a terrible example. However, Bose does have stellar multi speaker systems in other cars as do all the other top tier sound system companys. Its a smaller percentage that adhere to the fronts only theory nowadays and many of them just parrot that philosophy. How is your Vette set up?

 

It's true, the stereo hobby is on the decline and less and less people are concerned with staging. Front-only is still the mantra on sites that cater to the DIY/Active and advanced crowd.

My Saab has rear speakers for the benefit of rear passengers only. They do a pretty good job of wrecking the staging in the car unless they are muted.
Still,

In any case - It's a silly debate.

Some people are concerned with reproducing music as it was "intended to be" and as accurately as possible. IE: Stereo recordings playing from two channels.

Most people are concerned with what sounds better to them and that generally means "More = better. Louder = better." and "surrounded by sound" rather than "sitting in front of a stage."

There's nothing wrong with either goal, and one should consider what they want to hear if they are building a system for themselves and not for some judge that will listen to their car for two minutes and put some checks in a box here and there.

In any case, it's pretty easy to find out where you stand. In a decent (usually aftermarket) audio system, shut down your rear speakers and notice how the singer is now on the dashboard rather than your passenger seat. Notice the cymbal crash now comes from the left side view mirror instead of sitting on your shoulder.

 

This debate is so old...

 

IMO the money spent on rear speakers especially in a 2 seater like a vette is much better spent on nicer fronts or a better amp. in some cars where u have passengers alot or suv's i can understand having coaxials as rear fill on substantially less power or HU power just for rear listeners