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Opeler
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Discussion Starter · #1 · (Edited)
O.K. audiofiles, here is a question for you. I have four 6.5" 2-way Pioneer speakers in my GT. Two are mounted in the footwell and two in the rear side panels. They are all protected with speaker baffles. XTC 6-1/2" Speaker Baffles (3-1/4" depth) Protect your speakers at Crutchfield.com Also, the area behind is insulated with Dynamat.

The thing is that I am not happy with bass tones. Can anybody recomend 6.5" speakers that will improve low end tones without adding amplifier or switching to gigantic speakers? I cannot mount speakers under the rear shelf as the space is filled with spare wheel, fire extinguisher and the tool bag, so I want to maintain current speaker location.

Any experience with these speakers? https://www.amazon.ca/PIONEER-6-5-I..._SR160,160_&psc=1&refRID=SM1CP26QHP10R1XD0M5N
 

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I've done a fair amount of car audios in the past and in some circumstances I find those speaker baffles absolutely kill mid and low frequencies performance from 6.5" speakers. Maybe just try removing the baffles before changing your set up.
 

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Über Genius
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9,401 Posts
Quite often it's not the speakers that are the problem It's the signal that drives them.

As an example, I have two different Surround Sound receivers. Both have the same wattage, both have the same output print (7.1).

I am running fairly high end polkaudio speakers.

One system has incredible sound, the other has boring, pedestrian, sound.

I paid the same for both receivers and both were highly rated.

Your lack of bass might just be in the driver.
 

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Opeler
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pinballace has a good ear for those kinds of things and can probably give you some guidance. I haven't seen him active here for a while though. Maybe someone has his contact information they can provide you.
 

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Opeler
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Discussion Starter · #5 ·
I've done a fair amount of car audios in the past and in some circumstances I find those speaker baffles absolutely kill mid and low frequencies performance from 6.5" speakers. Maybe just try removing the baffles before changing your set up.
Just came back from the garage. I removed rear speakers baffle. Much better, thanks Vinnie. I would still like to find better speakers, though.
 

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Senior Contributor
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What do you have for an amplifier? If you are just running off the stock amp in the radio that is your next problem. You need more power to drive the speakers you have to get the desired bass response. If your radio has pre-amp outputs then you could add a better amp and not have to change the radio too.
 

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Just Some Dude in Jersey
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15,349 Posts
I profess no high end audio expertise, but I did sleep in a Best Western hotel last night. I've had good experience with Kenwood equipment over the years and I had upgraded my SolstOpel with a double din Kenwood touch screen with GPS and it sounded great. Just 23watts rms. But that car has a factory amp and a huge thumper behind the passenger seat. More than enough bass for me in that car and I listen to the bassiest varieties of heavy metal.

The sound system in my GTX turned out just as awesome and I just bought what was available in my price range at Best Buy and I didn't buy an amp. I'm running just the 23 watts from the Kenwood to Phase Linear 6x9's in the back and Kenwood 6.5" s in the doors. It THUMPS! And it's deep and rich throughout the bands with good clarity. I attribute the great sound to all the cabinet grade plywood in the back and the plywood/paneling in door panels and dash. It's also very open inside my car and my seat backs are minimal. All the sound sort of hits me just right and I haven't had to ever touch the balance or fade.

One thing I liked about the Kenwood systems I looked at was their Speaker Configuration Set Up screen. You can tell the stereo what size and type of speakers you have and which of 4 locations on each side of the car they're at. I think this feature works really good with this stereo. I tried telling it erroneous speaker sizes and locations and this caused the sound to change radically. Given the correct information it automatically set the sound distribution perfectly for my car.

:veryhappy
 

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Opeler
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Discussion Starter · #8 ·
I am also running Kenwood radio but I do not want touch screen, amplifier and similar wackadoodle. I want to keep it simple, so I would appreciate recommendation for the quality 6.5" speakers that will give decent low end sound.
 

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Opeler
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Hey Bro.

It's never gonna work, no matter what kinda speakers you buy, or how many amps you push through them.

Where does Bass, and speaker response come from?

The resonance of the chamber behind the speaker.

It should resonate off the hard surfaces behind it, and create a time delay, which means the tones reverbrate longer, and our ears hear as "Rich."

Your speakers are trying to bounce off "Sound Deadening Material," aka "DynaMat."

You see the problem?

You just need to build an enclosure for the speakers. Rather than throwing money at it trying to buy your way out of doing a little work.

I suggest you get out in the garage, before Summer is over, next week, for ya'll.
 

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Hey Bro.

It's never gonna work, no matter what kinda speakers you buy, or how many amps you push through them.

Where does Bass, and speaker response come from?

The resonance of the chamber behind the speaker.

It should resonate off the hard surfaces behind it, and create a time delay, which means the tones reverbrate longer, and our ears hear as "Rich."

Your speakers are trying to bounce off "Sound Deadening Material," aka "DynaMat."

You see the problem?

You just need to build an enclosure for the speakers. Rather than throwing money at it trying to buy your way out of doing a little work.

I suggest you get out in the garage, before Summer is over, next week, for ya'll.
Well you are close. I used to build speakers using an equation that took into consideration the free resonant frequency of the driver, the driver impedance, the enclosure stiffness, enclosure volume, bass port area, bass port length, crossover frequency, etc. etc. What actually happens in a tuned enclosure if it is sealed is that the air is used like a spring in order to increase the travel of the driver cone. Since it is impossible to be 100% efficient at all frequencies you wind up tuning the enclosure to a specific frequency and then there is a logarithmic curve that describes all other frequencies around the tuned one. Just adding an enclosure of any size behind the driver will not necessarily help. If it is too small and restricts the movement of the cone it will actually decrease the bass. In a ported system you are designing an enclosure volume and port geometry so that the wave emitted from the port is in phase with the wave emitted by the driver which then increases the bass that you hear due to the additive nature of the two waves. Just ask Dr. Bose.
 

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Opeler
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Discussion Starter · #13 · (Edited)
I used to build speakers using an equation that took into consideration the free resonant frequency of the driver, the driver impedance, the enclosure stiffness, enclosure volume, bass port area, bass port length, crossover frequency, etc. etc.
ARGH! I will stick to DSD carburetors music!!! :yikes:

P.S. Their tone changes with the engine displacement, intake trumpets length, camshaft duration angle, compression ratio and exhaust manifold diameter. Fine tuning is performed by changing engine rpm range.
 

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ARGH! I will stick to DSD carburetors music!!! :yikes:

P.S. Their tone changes with the engine displacement, intake trumpets length, camshaft duration angle, compression ratio and exhaust manifold diameter. Fine tuning is performed by changing engine rpm range.
Pump up the volume
Kick it up
You know how I like it

The crazy thing is that they growl in a deep tone.
Then you look at the tach... oh crud ...7000rpm's
 

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Opel Intern
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1,290 Posts
P.J. Can you find a model number on your stereo head unit? We can look up the unit and see its internal driver specs. Its likely possible that you can keep the same speakers you have and just up the wattage from the head unit with a different non-screen non-gimmick one. Its also possible that your current head unit doesn't have a wide enough frequency response range for your liking. The most common is 20-20kHz, but some cheaper models might not reach down that low and some premium drivers go as low as 12Hz - that is more of a 'feel' frequency than a 'hear' frequency.

I installed a number of stereos in friend's cars and there are usually huge improvements just by changing the head unit without having to touch the speakers. Some head units let you modify individual speaker tone settings which can really up the experience out of 'stock' car speakers.
 

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Opeler
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Discussion Starter · #16 ·
The following is technical specs of my radio:

The Kenwood KDC-BT555U utilizes a 24-bit digital to analog converter for superior sound quality.

MOSFET Amplifier: The Kenwood KDC-BT555U is equipped with a MOSFET amplifier. Compared to conventional power supplies, the MOSFET amplification circuit is smaller and more efficient, and it delivers increased power with less distortion and absolutely zero on/off switching noise. More power means louder and cleaner music at higher volumes because you're not pushing the limits of the amplification circuit. The power output specs for the KDC-BT555U are as follows:

Full Bandwidth Power: 22 watts RMS x 4 channels (at 4 ohms, 20-20kHz, 1% THD)
Maximum Output Power: 50 watts x 4 channels

6ch/2.5V Preamp Outputs: The KDC-BT555U features front, rear and subwoofer 2.5-volt preamp outputs. The front and rear speaker preamp outputs are balance and fade adjustable. The subwoofer preamp output is non-fading. The front, rear, and subwoofer preamp outputs are fixed to the rear chassis of the head unit.

Front & Rear High-Pass Filter: The KDC-BT555U features a High-Pass Crossover for the front & rear channels when your front & rear speakers are connected by the unit's speaker-outputs or preamp-outputs. You can adjust the high-pass crossover from "Through", 100, 120, or 150 Hz. The "Through" selection is a full-range setting.

Subwoofer Controls: The Kenwood KDC-BT555U offers the following subwoofer controls, when you are using unit's subwoofer preamp output.

Low Pass Filter: The receiver features a built-in Low Pass Filter control for the preamp-output, when the output is set to Subwoofer. You can select from 85 Hz, 120 Hz, 160 Hz, or off.

Subwoofer Phase: You can adjust the phase of the subwoofer output between 180-degrees (Reverse) or 0-degrees (Normal).

Subwoofer Level: Once the Subwoofer preamp output is activated, you can independently control the subwoofer preamp output level (-15 to +15) from the CD receiver.

Speaker Settings: The Speaker Setting function tailors the head unit's audio settings according to the type of speakers in your vehicle. You may select a Speaker Setting of 'SP-Off' (flat/off), 'SP-OEM' (for OEM factory speaker systems), 'SP-6x9/6' (for systems with 6" and 6"x9" speakers), or 'SP-5/4' (for systems with 4" and 5" speakers).

Preset EQ: Eight EQ curves are preset into memory, allowing you to recall the best preset EQ curve for different types of music. Each preset has its own level settings for bass (100Hz), midrange (1kHz), and treble (12.5kHz). You can choose from the following preset EQ curves - Rock, Pops, Easy, Top 40, Jazz, Natural, Game, and User.

Note: You can store bass, middle and treble tone settings for each source (CD, AM/FM, Aux, USB, iPod, Bluetooth, and Pandora).

Sound Enhancements: The head unit provides further sound enhancements for your car audio system.

Bass Boost: The Kenwood CD receiver features a Bass Boost control that can be set to the following levels (BB1, BB2, BB3, or Off).

Loudness: This function enhances low and high frequencies to make the sound clearer lower volumes. There are 3 levels (LV1, LV2, or Off).

Supreme Setting: When MP3 or WMA files encoded at a low bit rate (less than 96 kbps, 44.1k, 48kHz) are played, the Supreme Setting function restores their high frequencies so the sound quality is closer to files encoded at a high bit rate. The processing is optimized for the compression format and the bit rate used. When the Supreme Setting is Off, the unit plays the original sound stored in the audio file.

Volume Offset: The level of each source may be independently adjusted to prevent radical leaps in output volume when switching from one source to another. The available settings range from -8 to 0 (-8 to +8 for Aux source).
 

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Just Some Dude in Jersey
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15,349 Posts
Looks like I'm gonna be shopping for a sub-woofer........

I had to do a little repair to my dome light and secure and tidy up the wiring to it a little better. We've had 10 days in the high 90's with 50-60% humidity and driving a GT through Jersey traffic is the last thing I wanted to do. But, golly, I needed to test my dome light repair and give my new exhaust a real highway test. It turned out to be a low humidity evening with temps in the low 80's/high 70's. Perfect!

Hoo-boy did I have a good time! I think I blew my speakers. You know it was good ride when you blow your speakers. 85mph out and back on the interstate for an hour and a half. I kept hittin' Replay during a hard punching classic blues tune being covered by my favorite fast pickin' guitar hero, Frank Marino.

One of the rear speakers was flappin' like one of those gag fart bags you put under a seat cushion by the time I got home.

The new exhaust is AWESOME! Best GT exhaust I've ever had. No bass at all at highway speed, yet sounds like a hemi while cruisin' the downtown for babes. Perfect!

So, I'm thinkin' that I outta check out gettin' one of them subwoofers, plus a new set of 6x9's. I don't need any more volume than I already have and I never really went past 3/4 volume. Okay, maybe I was at 90-95% volume. Still, the speakers were rated to handle much more than what my head unit put out. I need to divert some of those ultra low bass frequencies to a dedicated speaker to lighten the load on the 6x9's.

I should have plenty of room to entertain a number of options, but I don't feel much like researching and calculating impedances and frequency bands. I'm going to start by dropping by a local stereo install place and see what they can analyze and offer me. They can analyze the sound distribution in the car. I'll probably want to do the install myself after they tell me what equipment I need. I don't actually want more bass than I already have, I just don't want to blow any more speakers.

I was also using Boom Mat speaker protectors behind my 6x9's and they definitely muffled the clarity of the bass. I wonder if they maybe didn't let the speakers "breathe" enough and that's why the speaker cone ripped?

:thinking:
 

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Senior Contributor
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I have a Alpine unit in the dash...not happy with this model I would Go for a nice Kenwood if it doesn't have all the flashy Lights.... Demo Mode :no:

Theses are my thoughts on Speaker Location...The best place is in the rear Deck under window either 6' or 6x9 works best
If your running 13" tires then..you stow a unmounted 13" tire in the Tire shelf
and if you get a flat you'll have a brand new tire to mount also It will slide under your speakers without hitting
If your running anything larger the unmounted tire will not fit! So Use the space for storage and get AAA

The rear deck under window and under tire shelf panel are the Best Locations in a GT
The speakers have room to breath To get the punchy Bass out and are not subject to vibrations and damp locations like in the doors and side panels over the years I find these the best Locations in my opinion.... and 45 watts per channel is plenty of power for our GT's
I think..
 

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Just Some Dude in Jersey
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15,349 Posts
I had to go to the dentist, same one I've had for 40 years, and he's a car buff, so I told him I'd show up this time in the GTX. On the way, I had the stereo on playing the exact same song that I thought had blown my speakers and, lo and behold, it turns out that my speakers weren't blown and I didn't detect the flappy fart bag sound I had heard on my previous joy ride. I punched the volume all the way up and no flappy distorted sound was detected.

So, I figure that my stereo's head unit must've been overheating from pumpin' up the jams for an hour and a half. Cooled off and not at max volume and everything works just fine.

:banana:

Dang. I was really looking forward to using this as an excuse to buy one them thunder boxes! Oh well, I guess I'll blow the money on cheap booze and even cheaper women!

:lmao:
 

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Opel Intern
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The following is technical specs of my radio:...
PJ - You have a very decent head unit already, so I doubt changing it will alter the performance of your speakers. The next thing to check about the current system is the wattage capability of your current speakers. And are they single cones or do they have one or two smaller tweeter and mid speakers combined into them? It is quite common for mid range plus speakers to have a small tweeter in the center of the larger cone so the kHz range of frequencies can be separated from the Hz range at the speaker.

If your current speakers are lower wattage speakers, they might not be able to accurately reproduce the low Hz sound at the volume level you need in a GT. Thankfully GTs are little cars, but they are all loud - especially if you have a sporty exhaust.

You head unit does have a signal pass through for a subwoofer amplifer. Which, if your current speakers are set up quite well I see as being a pretty good option. There are numerous 'woofer' cones which are small diameter and lowe height cones that incorporate an amplifier and are built to fit under a seat. I'm not sure about that prospect in a GT, but it might fit under the rear window shelf.

Bass in a car doesn't need a very direct route to the listener in order to be heard correctly. Especially in the sub 100 Hz zone.

If you want to identify where your system is going wrong, play this video through your system and see which tones are poorly represented.
 
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