I want to upgrade the old speakers in the door panels of a 4 year old car but am reluctant to simply attack the trim panels at random as I always seem to damage the clips and they never go back properly. Is there a more considered method or do I just grab and pull ? I've never been happy doing this to any interior trim.
Thanks,
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what car is it?
M
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Pete, if i've done this right, the link below is to a trim removal tool sold by Frost.
www.frost.co.uk/acatalog/Index_Interior_Trim_15.ht...l
HTH
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Pete,
The secret is knowing exactly which way to pull and where the fixings are hidden. Trial and error often ends up with breakage on modern cars. Some of the hidden fixings are very crafty.
Are you adding another power amp? Most modern car speakers are pretty well designed.
David
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The best place to put mid and high frequency drivers in a car is in the corner of the foot wells. Ideally you want the drive units equal distance from your ears. This is the only practicle place I have found where the differance in distance is the smallest. What speakers are you planning on using?
Ben
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IMHO, the last place to put medium/high range speakers is in the footwells. High frequyencies are very directional, so in the footwell, your ankles will hear it very well, but nowhere else. If you look in all the speaker installation guides, high frequency speakers should go on top of the dashboard or high on the door near the mirror. Low frequencies are omnidirectional, so you can basically but the bass unit anywhere in the car.
Andy
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In my experience, Mid/high range speakers should be places as high up as possible. High frequencies are very directional, so placing them in the footwell will give your ankles a treat, but not much else. If you look at proper installations, the tweeters are either on top of the dashboard near the windscreen or on top of the door panel near the mirror. Low frequencies, which are basically omnidirectional, can be fitted anywhere there is a suitable air gap (bottom of doors, footwell, parcel shelf, boot etc).
Andy
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High frequencies are very directional? What does that mean. In a car , loads of the sound that reaches your ears will have been reflected many many times. High frequency units have far better of-axis response and dispersion than woofers. Woofers are more directional than tweeters, but there placement is usually less significant becasue of the size of the wavelength of sound they produce. The car environment creates many many complexities. Situating drive units so they radiate directly into the windscreen isnt going to help. Think about how sound waves propagate. The ear cant tell how high or low speakers are in a car. Best to use tweeters mounted directly on the woofers axis in a car. If the hi-frequency units are placed on the dash it is very difficult to try and create a realistic stereo image. Stereo sound requires the head to shield some signal for the channel opposite to the ear that is recieving it. In a car if one speaker is very much nearer the driver than the other, this is greatly dimished due to the amount of reflections reaching the other ear from the near drive unit. This is why it is good to try and make the distances as near equal as possible.
However, total separation isnt good either, otherwise you achive a super-stereo effet as when using headphones without a cross-feed circuit.
Ben
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Pete W,
Some manufacturers make speaker 'upgrade' kits. These are available on a model-by model basis, but exactly which models I don't know. I have seen Panasonic and Sony upgrade kits for A4, BMW3, etc. Try your local car audio specialist.
Hope this helps,
Martin.
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Pete,
Haynes manuals normally give a comprehensive method of removing and fitting door panels. Best to check there first.
If you are fitting new speakers, please check the depth carefully - they may seem to fit nicely, but you only find out when you wind the windows down!
Hope this helps.
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ian (cape town) wrote:
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> Pete,
> Haynes manuals normally give a comprehensive method of
> removing and fitting door panels......
No they don't!!! Removing trim is one of my pet hates, Haynes manuals are good at showing the locations of obvious screws, then covering the hidden clips with a throw away comment like ' and remove clips' ARRRGGGG!!!!! Having said that I have had a Haynes manuel for every car that has passed my way and find that the coverage vaires greatly from car to car.
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Why can't radio manufacturers use a standard connector for radio output?. Every radio & car seems to be different so if you change the audio unit over it is a pig of a job to connect it all back together.
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I think most modern cars now have the standard ISO connector which allows easy changeover.
Thanks to the responses above, the car is a Galaxy and we've just replaced the standard Ford 6000 radio cassette with the new black panel SONY CD unit - very, very nice - but I think I'll get better by replacing the standard speakers. The SONY puts out 4 x52W as standard so I thought something about 70 -90 w speakers would be reasonable as they would operate at mid-range at 52W ( not likely to crank it up that much however ). I just don't like the distortion I get at the moment when I'm at half volume, say. I am assuming that existing speakers for teh standard radio are of the order of 27W'ish, unless somebody can advise differently.
Tried Haynes and they say call back in 6 months when a manual should be available.
I agree with Graham above, it's one of the worst jobs which is why I ask the question. Another tip is to do the job when parts are warmed on in warm weather as the clips are a little more forgiving.
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I doubt the distortion you are hearing has anything to do with reaching max input power. Max RMS values are really measurements of the thermal capability of the voice coil of the drive unit. They are not directly related to the max sound pressure output of a drive unit. I have heard defening levels of over 100db in someones living room using valve amps of less than 20 watts.
I expect the distortion you are hearing is non-linear distortions of the drive unit. It is far better to drive a loudspeaker with an amplifier whose specified output is greater than the drive unit is rated at, than it is the other way round.
If you want better speakers i would get an of the "car" speakers sold in car audio places. Better to buy proper hi-fi drivers. If you are intersted e-mail me and I could suggest some suitable units and cross-overs. The speakers in any sound reproduction system are by far the most important part.
Ben
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Ben,
Enjoy your posts, in particular on the performance car side of things. Also suspect from your comments you are interested in hi-fi.
That makes it puzzling that your views in many respects are the opposite to those I've held for 25yrs plus on home/car audio.
The area I would agree on is that it is better to feed a clean powerful signal to average speakers than a flat out low powered signal to top quality speakers. The distorted waveform (clipping?) from the strained amp will ruin the good speakers in no time.
As to bass/treble directional thoughts mine are the complete opposite.
I have always understood that the treble from domestic/car speakers was very directional and the bass far less so. It is said the treble unit should face the ear as far as possible. Home speakers should be situated with the treble unit at eye (ie ear) level when you are sitting. Many hi-fi speakers are assisted in the bass area by a secondary bass port that fires to the rear. In my own floor shakers the bass port fires down into the carpet, but you hear it OK.
Some high cost speakers even have their bass units pointing down. Try spinning the speakers round 180° (ahh a "degree", thanks guys) at home and you'll hear the bass but the treble vanishes. If next door has the stereo on too loud (they never do here though) all you will hear is the bass thump. I think the treble is lost due to direction and greater absorbtion.
Many home TV surround-sound systems have a subwoofer. What do they say about placing those? Often there is only one and it can be placed anywhere in the room as the bass sound isn't very directional.
To cars now. The same applies to subwoofers here as they are placed within the hatchback boot space on many I look after, with no holes to let the sound into the cabin...but the bass permeates the whole car. Put your treble units in the boot and you'd hear nothing from them.
In my own car I have some JBL dash mounted tweeters (£100 for two speakers that would fit in one hand) and the makers advised position is on the dash top or at the top front of the front doors......because the treble sound is directional. They must know what they are advising. These work well with the sound being part direct to ear and part reflected from the screen.
I don't ever think you can get true hi-fi in a car with a balanced frequency response, correct channel separation, positioning to suit all occupants, good placement of the soundstage.......but you can get a damm good/loud sound.
For a simple/value set-up over many years the advised route has been to have a pair of decent bass units in the parcel shelf. Note: The shelf needs to be reinforced or a well damped strong one like the ZX/Xantia.
Mid-range units can go in the normal front door positions and the tweeters on the dash each side.
If you like fit a power amp for the bass units and another one for the mid/treble units.
Feed with a clean signal from a CD player and you're away.
What do you think?
David
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Wow, someone has picked me up. What I wrote was true in many respects, but slightly misleading. I will try and explain myself better. I should have said that the off-axis response at a given frequency depends on the drive unit producing it. I.e. the dispersion of sound at say 2.5k is worse from a mid/woofer than it is from a tweeter.
Amplifier clipping is an important issue- particularly with speakers with passive crossover networks- is this what you use? If an amplifier is driven into clipping when trying to reproduce a large bass note the high frequency tweeter signal, which is riding on top of the bass waveform, gets chopped off in the amplifier, causing large amounts of very high frequency distortion. This could cause the tweeter to overheat and be damaged by a 50 watt, whereas it may withstand being driven at higher levels with a 200w amp. However, in an active system this concern would be irrelevant as the voice-coil of the tweeter would be connected directly across the amplifier providing maximum damping and control of the voice coil motion, without the decoupling of capacitors, resistors and inductors of a passive crossover. The result is lower distortion. An active system is capable of far higher undistorted output for a given overall amplifier output. I'd love to switch to a fully active system, but I can?t afford the additional amplifiers.
"Many hi-fi speakers are assisted in the bass area by a secondary bass port that fires to the rear. In my own floor shakers the bass port fires down into the carpet, but you hear it OK." I think what you are describing here is a bass reflex enclosure. I have used them in the past. The bass port is used as a harmonic resonator. The length/diameter of the port are tuned to create a volume of air that will resonate in phase with the cone motion, damping the cones motion at minimum driver response. So you are right the sound you are hearing at this frequency is predominantly from the port. It doesn?t matter whether the port fires to the rear or down, because the ear cannot pinpoint where frequencies below say 100Hz come form because of the size of the wavelength. A 28Hz wavelength for example is 17m long I think. The higher the frequency gets (within normal audible frequencies) the easier it is for the ear to detect where the sound is coming from. Hence positioning of tweeters is very critical. The smaller you make the tweeter the better the sound dispersion- as anyone who has heard a Hiquphon OW1 tweeter will agree. Many hi-fi tweeters use some degree of horn loading to improve sensitivity. This reduces high frequency output off axis. But with hi-fi tweeters you wish to hear the drive unit and not room reflections.
Earlier in the post I said bigger drive units will beam more at a given frequency, this is true, and why there are very few successful two-way loudspeakers using mid/bass drivers larger than 8". However, a very significant factor in the way the drive units radiates is the enclosure itself. Nearly all the hi-fi companies I see still use closed boxes, either vented or sealed. By using an open-baffle speaker sound dispersion etc are improved greatly. More details on this can be found at the excellent www.linkwitzlab.com site.
"I think the treble is lost due to direction and greater absorption." greater absorption. I think you have got something there. I have never understood exactly why treble frequencies decrease at a greater rate than bass with increasing distance. Vance Dickason in his Loudspeaker Design Cookbook, says that the main reason why a lot of film sound tracks are too hot (i.e. too much treble content), is because they are mixed far-field as opposed to near field for music recordings. He says at Disney for example they sit as far away as 60ft, so by the t
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My post was too verbose to fit!!
...time that they hear the sound form the speakers, the treble is not so loud. I?m not sure why, anyone have any ideas? I might post a question at the discussion group at www.madisound.com .
One reason for bass permeating through walls more than treble is because the SPL (sound pressure level) of the bass is likely to be much greater than the treble. Our ears are non-linear devices, and they are far more sensitive to mid-range frequencies than bass, as shown by the Flether-Munson curves.
£100 for two tweeters- these should be some serious units. But they sound seriously small do they have Neodymium magnets (cant spell that word!)? My Seas Excel tweeters are huge.
"don't ever think you can get true hi-fi in a car with a balanced frequency response, correct channel separation, positioning to suit all occupants, good placement of the soundstage.......but you can get a damm good/loud sound." Agreed, I have three-quarters of a decent system at home (not finished yet), and nothing much in the car, mine is FAR too noisy.
However, placing the mid-range and tweeters in different positions is a recipe for disaster. How can they ever be time aligned? Designing the crossover would be a nightmare. I recommended a good friend of mine to use a cheap poly carbonate 3/4" Audax tweeter, with a Peerless 5 1/4" car woofer, with the tweeter mounted to the grill of the woofer. We were going to start off with a first order filter on the woofer, and a second order on the tweeter. Moving the tweeter around creates many additional complexities. When designing hi-fi speakers the tweeter should be put as near to the mid-range as possible.
I?m still not quite sure what you mean by directivity of the sound being directly relative to frequency. Higher frequencies may reflect differently, I?m not sure?
I hope some of that was of interest!
Ben
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Ben,
You'll note I worried going against your previous posts because I guessed you had a real interest.
I think your first two posts didn't communicate the full message but it is a monster subject.
You are into it in a far more tech way than I am. I just know I have chosen all our domestic gear on extended comparative home audition and bought what suited out taste in sound character.
Cars are a bit oddball and I do the best I can with an existing system and minimal cost improvements.
All I was trying to say overall was that high frequency sounds can get lost if fired into the footwell from lower door positions (to take a common placement). Absorbtion or off-axix response...I don't know but I have heard (or rather not heard the HF) the problem many times. The simple addition of quality dash mount HF units can be an easy improvement.
Thanks.
David
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Yeah i didnt really get the point across well. Im going to stop posting, and do some more reading and learning. I have only limited experience in car audio.
"bought what suited out taste in sound character"- but remember, hi-fi is not subjective like wine tasting, there is always an absolute reference and that is the unamplifed origianl sound.
Happy listening.
Ben
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The reference sound may not be subjective but people are!
We'll have to do home hi-fi another day when Martyn's not looking.
David
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One side effect to those of us who were young in the 60s and 70s (roc and roll will never die!)is that by now we have very little high frequency hearing left so the as fitted sound systems sound just the same as the mega ££ systems (with the xeception of subwoofers as the low end is the last to goa and we in any case can still 'feel' the low notes in our gut if not with our very knackered ears...
the youth of today with the earbuds from their mp3 players (that can be heard by others 10 feet away) will heve to wait for a much shorter time than we did to reach this econimic 'benifit'
¬R
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This is very true. Apparently, Pete Townsend first noticed his serious hearing damage when he couldnt even hear his telephone ring!
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Phew! Now can someone explain why all those damn buttons are so tiny we can hardly see them, let alone find out what they're for.
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Brian - Methinks Ian is teasing you! Have a look at www.petetownshend.co.uk/frame.html and see
if there are any clues there about "you know *who*"!
Yoohoo!
Ronnie
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It's allright, I was teasing him as well!
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Ever noticed that when you look into the back of a teaspoon, you look just like pete townsend?
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Ian
Oh dear! You really must try to get out more!
Ronnie
PS I've just had a look and you're quite right. Sorry, got to go now. Matron says it's time for my medication ....
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