Audio question - hardly a 911 tech question, but still...

[pub911]

After reading all of the posts above (thanks everyone) I'm wondering if the issue is not power, or speaker selection, but installation.

I'm using an enclosure sold by Pelican (Moch-1 underdash). Here's the link: Pelican Parts - Product Information: PEL-MOCH-2000S

The enclosure does not completely seal around the edges, and the back of the speakers, the magnet, may actually be in contact with the structure of the car. Would this cause me to lose mid-range and overall volume, forcing me to push the volume to the point of distortion in order to hear the tunes over the open-roof road noise?

Are there installation instructions or does anyone have any guidance to help me improve the job I've done?

[RWebb]

I had one and sold it - put the speakers in the door. Best place to mount the tweeters is in the corner where the windshield, dash & A-piller all come together.

That may not solve your top off noise issue, but will be better than the mock-1 (no, I did not mis-spell it).

[Cajundaddy]

Originally Posted by RWebb

I had one and sold it - put the speakers in the door. Best place to mount the tweeters is in the corner where the windshield, dash & A-piller all come together.

That may not solve your top off noise issue, but will be better than the mock-1 (no, I did not mis-spell it).

Yes exactly. Overstating the obvious but the closer you get speakers to your ears, the better you will hear them, especially tweeters.

[McLaren-TAG]

Not simply closer, but also line of sight. The higher the frequency the more directional it is, so pointing the speakers towards your ears especially the tweeters will give you better results and better 'staging' of the sound.

[wwest]

Originally Posted by pub911

I've got a 78 911SC Targa. I fitted it with an aftermarket subwoofer enclosure with a pair of 10" woofers. The front speakers are Boston Acoustic separates. The power comes from an alpine 1000w (250 per each of the 4 channels). The sub is using channels 3+4 bridged and bypassed for low-end, and the fronts are stereo and filtered for high-end.

The problem is, I don't get enough punch from the bass NOR do I get enough clean volume from the front.

Given that most modern day amps have a MOSFET DC-DC voltage upconverter/inverter, 12 volts to 200+ volts, with 250W/speaker you're undoubtedly overdriving the voice coils, speaker travel limits.

It all sounds great in the garage, but at speed, with the top down, I find myself pushing to the point of distortion.

No kidding, this is a 911, NOT an LS400, and even at that TOO much POWER with no way to overcome road noise

One more detail - the front speakers are installed above my knees in one of those aftermarket speaker enclosures that cover all the mechanical stuff in that area (from the edge of the lower dash lip to the firewall.

Do I have enough power?

Your probem, CLEARLY, is not a lack of power, insulation against car, tire, and overall road noise IS!

Am I expecting too much from the fronts, given the way I've installed them (not in the doors, and therefore no cavity to reverberate).

Your problem is a BASE one, the 911 "platform".

If I added more power (another amp) and dedicated 1000w to the front and another 1000w to the sub, would that do it with fidelity?

More power will only help if dedicated to an "anti-noise" device.

Open to all suggestions.

To appreciate what you have you need a Lexus LS4XX and a 120A alternator upgrade. Or you could settle for the more than satisfactory LS4XX sound system. But given the overall tone of your post you probably already have coffee can extensions on the exhaust tips and that doesn't look good on a 911, let alone an LS400.

There is NO audiophile worth their salt that would go to the EXTREME sound level you are touting, certainly not, NEVER, in a 911. Sorry this previous statement is just WRONG. There is NO car venue would that would justify your extreme.

Absent having a concert hall no TRUE, actual, audiophile would go to those EXTREMES.

But good luck with your hearing once you reach your seventies, or even sixties.

Oh, my '78 Targa has a Kenwood "head", a Kenwood multi-CD player under the passenger seat aong with a Kenwood 5 channel 250 watt Amp. 4 upgraded dual cone speakers (6.25" front, 6X9" rears) with integrated crossovers (polarized capacitors GONE!). Kenwood Amp. includes a DC-DC voltage up-converter, ~200 volts for PEAK drive to those speakers.

NOT a RICER or teenager (72) so sub-woofer NOT required.

Nice system if/when I'm going slow enough, say in a rresidentual area or city stop and go traffic. On the road "at speed", top on or off, system OFF.

Oh, QUIETEST summer use only tires that are available for a 911, and a spray can (4) of undercoat discharged into each wheelwell.

[McLaren-TAG]

Originally Posted by wwest

There is NO audiophile worth their salt that would go to the EXTREME sound level you are touting, certainly not, NEVER, in a 911. Sorry this previous statement is just WRONG. there is NO car venue would that would justify your extreme.

Absent having a concert hall no TRUE, actual, audiophile would go to those EXTREMES.

But good luck with your hearing once you reach your seventies, or even sixties.

To each his own... I mean that's coming from a guy with a completely removed stereo in his 911 but what's the difference between an extreme audio system and an extreme engine build or an extreme suspension build?

The most valid point in your post and the one thing I do hope he takes your advice on is the hearing loss.

[SilberUrS6]

Originally Posted by McLaren-TAG

The most valid point in your post and the one thing I do hope he takes your advice on is the hearing loss.

wwest's posts must be read with a generous helping of salt.

[wwest]

Originally Posted by McLaren-TAG

To each his own... I mean that's coming from a guy with a completely removed stereo in his 911 but

what's the difference between an extreme audio system and an extreme engine build or an extreme suspension build?

None, basically. But Op mentions "fidelity", "clean volume", and "pushing to the point of distorton".

The most valid point in your post and the one thing I do hope he takes your advice on is the hearing loss.

How many us would tackle an extreme engine rebuild, 800 HP, say, without KNOWING that ancillary issues (suspension?) would have to be addressed in order to take advantage of that 800 HP.

Op, in effect, is building a 1000 HP engine without addressing some very obvious ancillary issues, like the WRONG car to begin with.

[wwest]

Originally Posted by fanaudical

I'm also curious about what the "real" background sound level of a Targa is (not so much for stereo stuff but for hearing preservation). Does anybody have real values?

That depends on tires, roadbed type/condition, top on/off, wheelwell/carpet insulation, and.......

SPEED (wind noise)!

Basically there is NO audio sound system that will be functional fidelity wise in a 911 "at speed". Well, maybe the 996 and beyond.

But even my '01 C4 benefitted greatly from "quiet" summer use only tires and a spray can of undercoat into each wheelwell.

[nineball]

Originally Posted by cdrik915

Using 3+4 channels bridged is not suffisant to have a good subwoofer level.


You should buy an amplifier .


Just my 2 cents.

if the amp really has an output of 250rms per channel bridging channels 3 and 4 will be more than enough to drive about 95% of the subs available today. i run a pair of 8" subs that are seeing less than 200rms each and it is overpowering if i want it to be.

Originally Posted by Hunt3R

In my 911 coupe right now I have yet to install a subwoofer, it's my first car in 20 years without one. I just have a 100w Pioneer head unit powering two Sony XPlod 6.5's w/ 2 tweeters in the doors and two 6x9's in a custom built deck under the back window and on the interstate with the windows down and the sunroof open I still can't turn it up all the way. The 6x9's bouncing off the back window are the loudest, I actually fade it back to them slightly to prevent the front speakers from distorting when I have to turn it up. If I end up installing bass, I've been thinking a powered, low-profile sub that will fit under the passenger seat will suffice. Granted that won't be shaking the car next to me at a stoplight, but I still don't expect I'll have any problems hearing and feeling it.

no aftermarket headunit in the world puts out 100rms. the average is 18w per channel and if you get certain alpine units you can buy a very small add-on to the hu amp that ups it to 45w per channel.


your front stage distorts for one of 3 reasons:

1. you are sending them too much power
2. you are sending them a clipped signal
3. your crossover point it not high enough for the speaker

i currently run an active system consisting of a pair of 1" tweets, a pair of 6.5" midrange in the door and a pair of 8" subs in a rear seat delete i made. they are powered by an alpine pdx5 (roughly 120x4, 400x1) but i am by no means using all of that power. my system is more than adequate for open top driving on any road.

OP, i would suggest moving the speakers into the door to start, but also adding some vibration control of some sort. that will dramatically increase the output of your front stage. see my audio build thread for detailed pics on how i treated my doors. i would also suggest crossing your front stage at 100 at a minimum, maybe even 120. let your sub handle the sub duties, that is it's job. low frequencies are omnidirectional, and in the small cabin of a 911 you should be fine without any time alignment.

what are the specs on your subs and the enclosure? installing them with too much, or too little, airspace can make any sub sound like garbage.

[RWebb]

another problem with the Mock-1 'enclosure' is that speakers should be rigidly mounted & that thing is flimsy & flexible

[brads911sc]

I am waiting for the ebay pic of the spray can of wheel well undercoat next to his SPAL fans... Welcome WWEST, I am glad to see you are the resident expert on this as well...

Originally Posted by wwest

There is NO audiophile worth their salt that would go to the EXTREME sound level you are touting, certainly not, NEVER, in a 911. Sorry this previous statement is just WRONG. There is NO car venue would that would justify your extreme.

Oh, QUIETEST summer use only tires that are available for a 911, and a spray can (4) of undercoat discharged into each wheelwell.

[Hunt3R]

Originally Posted by nineball

no aftermarket headunit in the world puts out 100rms. the average is 18w per channel and if you get certain alpine units you can buy a very small add-on to the hu amp that ups it to 45w per channel.

Yup I meant total power, the amount of power being talked about here just surprises me unless we're building a competition audio system here to blast away everyone in a parking lot, but especially if it's hard to hear. I was actually incorrect about my headunit too, it's 50x4 peak (how they advertise it of course), 22x4 continuous, or 14x4 RMS and I've found this to be more than adequate for my two 6x9's in back and 6.5's w/ tweeters in front.