Thread: New stereo install sounds horrible

Sounds like a perfectly normal reaction to an install that uses standard speaker locations and sizes.

It's an unfortunate byproduct of placement and the resonant frequencies in the cabin along with inadequate drivers.

custom door enclosures and larger midbass drivers will help, but theres no getting around the fact the acoustics are junk

I inadvertently wired one of the 6 speakers in my Defender the wrong way around.(positive wire in the negative terminal) It didn't sound right, so pulled everything out again and checked. When I corrected my cock-up the results amounted to quite an astonishing change. I've copied from the web what was wrong. This might be your problem.

"If one of your speakers is wired up the wrong way it will be 'out of phase'. In other words it will be moving 'back and forth' while the other speaker is moving 'forth and back'. Your ears may not notice it but this results in the stereo seperation and sound quality not being as good as they could be."

Don.

My experience (many years playing with stereos in car and home) - would support the out of phase suggestion. In my experience even good 4" speakers are really effectively midrange and tweeter - but given you have the back and sub still going - they should be ok.
Cheers Nobby

Watch out for speakers that have incorrect =ve and +ve labels from the factory!

Originally Posted by ClassicRR

Hi All,
...
My question to all the knowledgeable people on this forum is could it be that I hooked up the head unit to the original speaker wires.
...
Cheers,
Richard

Richard,
Before you go tearing into the install again, Ask yourself how you verified the wiring from the head unit to the factory plug - and for the purpose of "it's been butchered before I got there", let's also work from first principles - i.e. the connectors on the speakers have different size spade lugs, so you (in theory) 'can't screw it up' - from a polarity perspective, if you wired the speakers and the head unit correctly (matching the existing connectors).

Phase cancellation on this install would produce a different result to claimed perceptioons. Insofar as the phase cancellation is concerned, a bass standing wave that you are "missing" is already 3x longer than your vehicle. So unless you have a subwoofer that is firing directly towards your seating position, you are going to miss about 2/3 of that anyway, and whatever else is in the way that will absorb or diffuse the waveform.
The same goes for every other frequency in the spectrum - they all have different reflective qualities and materials inside the cabin absorb, diffuse and reflect these frequencies differently - so much so that you're looking at an exercise in futility if you think a car can sound anything like a home stereo. Just forget it.

What you CAN do about it, is to EQ the output appropriately, install better amplification and better (larger) midbass drivers and preferably use separates with either an active or passive crossover of your choice. a 4" driver is essentially an upper-mid and almost a tweeter. For any kind of half-reasonable mid-bass you need a dedicated 6.5" or larger driver in these vehicles, and the crossover absolutely has to roll it off below 125hz and above 600Hz. So, you're already looking at a 3-way crossover to make the front sound stage "work" acceptably and to position the tweeters lower than you perhaps think - because the reflections in an RRC are absolutely demonic for upper frequencies. The factory speaker grille midway up the door is not a bad place to hide a tweeter, but some careful positioning will be required so that the tweeter does not overpower the rest of the stage. (hence requirement for EQ).
The bottom of the door can work well as a mid-bass, but there is very limited room for a large driver, without adequate spacers. Or custom door pod fabrication. It's still (in my opinion) a bit of a waste of time, BUT it is a much-needed addition if you want anything half-decent coming from the front.
Even so, when you are driving, no matter how much dynamat and dynaliner you have in the vehicle, the fact that the car is a giant box, means that the wind noise from the a-pillar area and side glass will ALWAYS have an effect on the sound - and it is a detrimental one (yes you will turn it up far louder than you thought at highway speeds)

SO... let's just roll with the fact that you do check your work, you're not prone to making silly mistakes and you purchased quality speakers and head unit.

The head unit will not have enough grunt to drive the front - despite whatever the label says. 50wRMS per channel? sorry, it's all BS - the best you could expect is about 18-20W RMS into 4Ω. Not only that, the fron is where you need ALL your grunt. Rear fill is miniscule in terms of requirement - and the placement of the rears is already going to overpower the front stage, due to their "direct fire" location.

So, either live with the lack of grunt from the head unit, bridge the outputs on the headunit to just a L/R channel and use the internal amp to power only the front - or get a separate 4/5 channel amp (depending on sub requirement or not) to power everything.

Without knowing your headunit brand and specs, The rule of generalised installs prevails - i.e. you typically have 4 channels out, so 4 colours and 4 colours with black traces. those represent each channel +ve and their respective -ve with the trace. So long as you correctly wired the outputs to the correct wires at the factory plug connection (removed plug or adapted etc) then there will be no issue with polarity/phase, unless there is a problem with the actual manufacturing of the speaker (unlikely on a good quality speaker).

Which brings it full-circle. You can use the EQ in the head unit to knock back the high frequencies and boost the low-mids, which is typically where the RRC suffers, and if you are having issues in the 500-1200Hz range, particularly if the reproduction is starting to get 'muddy' or you're having to drive it so hard that it introduces distortion or clipping then you're going to need to do some more homework on the speaker/amp front.

But as I said in my previous post... the RRC's acoustics are atrocious at best. You can't make a silk purse from a sow's ear.

You CAN improve over standard, but it comes at a cost and a fair bit of effort. Moreover, it takes time. If you can get access to a spectrum analyzer or a tone sweep generator track, or your laptop can act as the analyzer, then I highly recommend you run a number of sweeps to see where all the resonant peaks are and where those huge troughs occur within the vehicle. It will help you a LOT when it comes to properly EQ'ing or choosing a crossover frequency that assists.

But I am afraid you are expecting too much from your 4" drivers at the outset.

Originally Posted by Mercguy

Richard,
Before you go tearing into the install again, Ask yourself how you verified the wiring from the head unit to the factory plug - and for the purpose of "it's been butchered before I got there", let's also work from first principles - i.e. the connectors on the speakers have different size spade lugs, so you (in theory) 'can't screw it up' - from a polarity perspective, if you wired the speakers and the head unit correctly (matching the existing connectors).

Phase cancellation on this install would produce a different result to claimed perceptioons. Insofar as the phase cancellation is concerned, a bass standing wave that you are "missing" is already 3x longer than your vehicle. So unless you have a subwoofer that is firing directly towards your seating position, you are going to miss about 2/3 of that anyway, and whatever else is in the way that will absorb or diffuse the waveform.
The same goes for every other frequency in the spectrum - they all have different reflective qualities and materials inside the cabin absorb, diffuse and reflect these frequencies differently - so much so that you're looking at an exercise in futility if you think a car can sound anything like a home stereo. Just forget it.

What you CAN do about it, is to EQ the output appropriately, install better amplification and better (larger) midbass drivers and preferably use separates with either an active or passive crossover of your choice. a 4" driver is essentially an upper-mid and almost a tweeter. For any kind of half-reasonable mid-bass you need a dedicated 6.5" or larger driver in these vehicles, and the crossover absolutely has to roll it off below 125hz and above 600Hz. So, you're already looking at a 3-way crossover to make the front sound stage "work" acceptably and to position the tweeters lower than you perhaps think - because the reflections in an RRC are absolutely demonic for upper frequencies. The factory speaker grille midway up the door is not a bad place to hide a tweeter, but some careful positioning will be required so that the tweeter does not overpower the rest of the stage. (hence requirement for EQ).
The bottom of the door can work well as a mid-bass, but there is very limited room for a large driver, without adequate spacers. Or custom door pod fabrication. It's still (in my opinion) a bit of a waste of time, BUT it is a much-needed addition if you want anything half-decent coming from the front.
Even so, when you are driving, no matter how much dynamat and dynaliner you have in the vehicle, the fact that the car is a giant box, means that the wind noise from the a-pillar area and side glass will ALWAYS have an effect on the sound - and it is a detrimental one (yes you will turn it up far louder than you thought at highway speeds)

SO... let's just roll with the fact that you do check your work, you're not prone to making silly mistakes and you purchased quality speakers and head unit.

The head unit will not have enough grunt to drive the front - despite whatever the label says. 50wRMS per channel? sorry, it's all BS - the best you could expect is about 18-20W RMS into 4Ω. Not only that, the fron is where you need ALL your grunt. Rear fill is miniscule in terms of requirement - and the placement of the rears is already going to overpower the front stage, due to their "direct fire" location.

So, either live with the lack of grunt from the head unit, bridge the outputs on the headunit to just a L/R channel and use the internal amp to power only the front - or get a separate 4/5 channel amp (depending on sub requirement or not) to power everything.

Without knowing your headunit brand and specs, The rule of generalised installs prevails - i.e. you typically have 4 channels out, so 4 colours and 4 colours with black traces. those represent each channel +ve and their respective -ve with the trace. So long as you correctly wired the outputs to the correct wires at the factory plug connection (removed plug or adapted etc) then there will be no issue with polarity/phase, unless there is a problem with the actual manufacturing of the speaker (unlikely on a good quality speaker).

Which brings it full-circle. You can use the EQ in the head unit to knock back the high frequencies and boost the low-mids, which is typically where the RRC suffers, and if you are having issues in the 500-1200Hz range, particularly if the reproduction is starting to get 'muddy' or you're having to drive it so hard that it introduces distortion or clipping then you're going to need to do some more homework on the speaker/amp front.

But as I said in my previous post... the RRC's acoustics are atrocious at best. You can't make a silk purse from a sow's ear.

You CAN improve over standard, but it comes at a cost and a fair bit of effort. Moreover, it takes time. If you can get access to a spectrum analyzer or a tone sweep generator track, or your laptop can act as the analyzer, then I highly recommend you run a number of sweeps to see where all the resonant peaks are and where those huge troughs occur within the vehicle. It will help you a LOT when it comes to properly EQ'ing or choosing a crossover frequency that assists.

But I am afraid you are expecting too much from your 4" drivers at the outset.

What he said...

I've been 'playing' with home hifi for years, but I just learned a lot from this post. Gives me a whole new warren of rabbit holes to explore for wiring up the OKA.

Cars are a terrible environment for audio, and getting something "good" is going to cost $$$. If you want the audio experience of, say, a Rolls Royce Phantom, you will probably need to visit your Rolls Royce dealer.

I didn't want to come over all authoritarian or make it sound like I am some kind of car audio guru - but I have been around the stuff for over 3 decades and the sad reality is the industry is SMALL. And it doesn't change...
Leon is still at soundlabs, Marty still has FHRX studios and Drew still runs Northfield in Brisvegas - and it's been that way since moses was a kid. and I could go on about the who's who, but those are three guys who were into it before I got my drivers license.

I especially learned a lot from Leon when discussing Becker installs in Mercedes, and Drew and Marty have helped do custom work for me several times over the years.

Problem with car audio is the chasm between quality and price. literally nothing good is cheap. For example, I had a maybe 15 year old pioneer reference single din headunit (well outdated) in the RRC until xmas, when I replaced it with a flip up carplay unit... the new unit (not a pioneer reference standard head unit) was over a grand. It's good, but it's not what I'd call reference. I put that in the RRC to make my trip north bearable and for a bit of iphone connectivity (hands free) and it's great for that, but there's no real grunt in the head unit....
and be buggered if I was going to pull out my old Focal reference monoblocks for a range rover install. But being the "fool" I still parted with dosh to get some decent drivers in there and while focal flax drivers aren't everyones cuppa, they are what I call decent. Not priced like utopia Be or Morels or Dynaudios, but these have to 'handle' the RRC environment, which I know for a fact a dynaudio wouldn't...

If that all sounds like jargon, let me get to the point from another tangent.

The law of diminishing returns applies to car audio just like it does to getting power out of a 3.9 v8. Standard is barely adequate, but you can live with it - but to get what you want, you're going to throw close to 10K at a stereo, before you can actually qualify it as 'sounds great'

How so?

Head unit - 1k-4K budget depending on your erm.... 'preferences' (can you really afford that Naka on ebay?)
multichannel amp - 1500-5000 - brand and specification and number of channels - more you want, price goes up.
dynamat/dynaliner - 800-2000 depending on how much of the car and what stage you need/want (materials only)
custom fitout work - $150-200 per hour for someone who is a Professional (and trust me, that's cheap for what you get- not just peace of mind that your car's electrics and interior are going to survive an install)
Cabling - if you love monster cable and you think you need six 1 farad caps... well say hello to the moths in your wallet that you haven't seen before.... - but 500-1k will get you a proper pro install for all power and speaker cabling, all the connectors and busbar etc

And I'm not adjusting for 2023 inflation....

Then you need to actually spend time and callibrate/tune the system - both to the frequency response and resonant peaks in the vehicle AND the owners personal music taste.... which has a huge effect on the actual EQ'ing of the system (moreso if they have no taste and use low quality mp3's as source sound)

Now I hope that is a solid foundation on why car stereo installs are both expensive and time consuming.

Not only does a professional installer know how to make it sound good, they can do it at nearly every budget point, and explain the limitations at certain price points - because not everyone has a vault full of gold bullion under their bed.

You can EQ your own system if your headunit has time alignment functions and EQ adjustments, and that will take all the guesswork out of the setup for you with a minimum of fuss - but you will pay more for the headunit...

Or if you are a propellerhead, you can use TA/EQ/sweep generators on a laptop and a high quality studio mic to sample the vehicles interior, and then custom eq or build crossovers etc, if that is what you want to do to get the desired result (and can be done on a tight budget - just takes a LOT of time)

Back in the day, it was buy a headunit, buy some aftermarket speakers, cut a hole in the doorcard and screw them in, run the wire through the doorjamb under the dash and into a fresh hole you just massacred in your first car's dashboard/console (did they have a centre console back then???) and that was that - you had FM radio and a cassette deck and you could play your mates mix tapes while the headunit was cranked to distortion+ levels and everything sounded 'better'... but really let's face it, it was **** and we still loved it.

Then someone decided that you could put home audio stuff in cars.... then we got car power amplifiers and graphic equalizers with flashing LED's and then CD players were the rage.... then double din CD and DVD players and then screens and now it's all on a phone and plugged into the MOST bus on the integrated audio system in your fancypants corolla or kia rio.

The RRC was designed when 8 track players were cool.
Vehicle audio acoustics were not foremost in the minds of the design engineers.

we're almost 5 decades on. Your phone has more smarts than ten thousand RRC's brains wired together.

Your phone can play music and generally speaking has better acoustics than the range rover.

If you think about it, the best way forward is to simply have some kind of receiver/amp that your phone can plug into and charge or connect via bluetooth or wifi, and use the phone smarts rather than buy another piece of car audio boat anchor that will be obsolete in 2 years.

Spend money on multichannel amps for high power and good clean audio signal, and buy some decent component speakers - 2 or 3 way with a passive crossover, pay a reputable installer a fair price to do the install and tune it for you, then enjoy it.

or DIY it, and take your time, save some $$$

When you go down this rabbit hole, it starts to cost money. very quickly. I'd urge restraint and spend the money on the things that help the vehicles NVH levels before upgrading the stereo.

and yes, it's very easy to spend 2 grand on dynamat extreme and dynaliner etc. but it makes a world of difference if it's done properly.
There's 500 bucks worth of material consumed in the roof alone. - good time to redo the headliner as well if it's showing signs of droop or ageing.

Also - if you do DIY - be prepared to deal with some really ugly discoveries..... like rust. or butchered wiring harnesses. Attend to that stuff as best you can - but don't ignore it, or your dynamat install will be a waste of time.


I see potential money pit in a stereo install. It IS wasted money if you ever decide to sell the car - does nothign for the overall value whatsoever, so also keep that in mind....

Originally Posted by Mercguy

I didn't want to come over all authoritarian or make it sound like I am some kind of car audio guru - but I have been around the stuff for over 3 decades and the sad reality is the industry is SMALL. And it doesn't change...
Leon is still at soundlabs, Marty still has FHRX studios and Drew still runs Northfield in Brisvegas - and it's been that way since moses was a kid. and I could go on about the who's who, but those are three guys who were into it before I got my drivers license.

I especially learned a lot from Leon when discussing Becker installs in Mercedes, and Drew and Marty have helped do custom work for me several times over the years.

Problem with car audio is the chasm between quality and price. literally nothing good is cheap. For example, I had a maybe 15 year old pioneer reference single din headunit (well outdated) in the RRC until xmas, when I replaced it with a flip up carplay unit... the new unit (not a pioneer reference standard head unit) was over a grand. It's good, but it's not what I'd call reference. I put that in the RRC to make my trip north bearable and for a bit of iphone connectivity (hands free) and it's great for that, but there's no real grunt in the head unit....
and be buggered if I was going to pull out my old Focal reference monoblocks for a range rover install. But being the "fool" I still parted with dosh to get some decent drivers in there and while focal flax drivers aren't everyones cuppa, they are what I call decent. Not priced like utopia Be or Morels or Dynaudios, but these have to 'handle' the RRC environment, which I know for a fact a dynaudio wouldn't...

If that all sounds like jargon, let me get to the point from another tangent.

The law of diminishing returns applies to car audio just like it does to getting power out of a 3.9 v8. Standard is barely adequate, but you can live with it - but to get what you want, you're going to throw close to 10K at a stereo, before you can actually qualify it as 'sounds great'

How so?

Head unit - 1k-4K budget depending on your erm.... 'preferences' (can you really afford that Naka on ebay?)
multichannel amp - 1500-5000 - brand and specification and number of channels - more you want, price goes up.
dynamat/dynaliner - 800-2000 depending on how much of the car and what stage you need/want (materials only)
custom fitout work - $150-200 per hour for someone who is a Professional (and trust me, that's cheap for what you get- not just peace of mind that your car's electrics and interior are going to survive an install)
Cabling - if you love monster cable and you think you need six 1 farad caps... well say hello to the moths in your wallet that you haven't seen before.... - but 500-1k will get you a proper pro install for all power and speaker cabling, all the connectors and busbar etc

And I'm not adjusting for 2023 inflation....

Then you need to actually spend time and callibrate/tune the system - both to the frequency response and resonant peaks in the vehicle AND the owners personal music taste.... which has a huge effect on the actual EQ'ing of the system (moreso if they have no taste and use low quality mp3's as source sound)

Now I hope that is a solid foundation on why car stereo installs are both expensive and time consuming.

Not only does a professional installer know how to make it sound good, they can do it at nearly every budget point, and explain the limitations at certain price points - because not everyone has a vault full of gold bullion under their bed.

You can EQ your own system if your headunit has time alignment functions and EQ adjustments, and that will take all the guesswork out of the setup for you with a minimum of fuss - but you will pay more for the headunit...

Or if you are a propellerhead, you can use TA/EQ/sweep generators on a laptop and a high quality studio mic to sample the vehicles interior, and then custom eq or build crossovers etc, if that is what you want to do to get the desired result (and can be done on a tight budget - just takes a LOT of time)

Back in the day, it was buy a headunit, buy some aftermarket speakers, cut a hole in the doorcard and screw them in, run the wire through the doorjamb under the dash and into a fresh hole you just massacred in your first car's dashboard/console (did they have a centre console back then???) and that was that - you had FM radio and a cassette deck and you could play your mates mix tapes while the headunit was cranked to distortion+ levels and everything sounded 'better'... but really let's face it, it was **** and we still loved it.

Then someone decided that you could put home audio stuff in cars.... then we got car power amplifiers and graphic equalizers with flashing LED's and then CD players were the rage.... then double din CD and DVD players and then screens and now it's all on a phone and plugged into the MOST bus on the integrated audio system in your fancypants corolla or kia rio.

The RRC was designed when 8 track players were cool.
Vehicle audio acoustics were not foremost in the minds of the design engineers.

we're almost 5 decades on. Your phone has more smarts than ten thousand RRC's brains wired together.

Your phone can play music and generally speaking has better acoustics than the range rover.

If you think about it, the best way forward is to simply have some kind of receiver/amp that your phone can plug into and charge or connect via bluetooth or wifi, and use the phone smarts rather than buy another piece of car audio boat anchor that will be obsolete in 2 years.

Spend money on multichannel amps for high power and good clean audio signal, and buy some decent component speakers - 2 or 3 way with a passive crossover, pay a reputable installer a fair price to do the install and tune it for you, then enjoy it.

or DIY it, and take your time, save some $$$

When you go down this rabbit hole, it starts to cost money. very quickly. I'd urge restraint and spend the money on the things that help the vehicles NVH levels before upgrading the stereo.

and yes, it's very easy to spend 2 grand on dynamat extreme and dynaliner etc. but it makes a world of difference if it's done properly.
There's 500 bucks worth of material consumed in the roof alone. - good time to redo the headliner as well if it's showing signs of droop or ageing.

Also - if you do DIY - be prepared to deal with some really ugly discoveries..... like rust. or butchered wiring harnesses. Attend to that stuff as best you can - but don't ignore it, or your dynamat install will be a waste of time.


I see potential money pit in a stereo install. It IS wasted money if you ever decide to sell the car - does nothign for the overall value whatsoever, so also keep that in mind....

Thank you all for your replies, especially Mercguy, The detail that you have gone into is next level.

I checked the polarity with a multimeter and you are correct in me assuming that the speakers are correctly factory wired. I should grab a 9v battery and check. When I say decent speakers, I'm talking about decent for me, not just a cheap pair of Pioneer or something.

The type of setup that you are talking is next level and it's not what I'll be going for, My Rangie is a little rough and will never be an original show car, But I managed to get what I want out of the 3.9l v8 with a 5.7l LS1

The entire roof and floor has been Dynamat'd, so it a good start. I've bought a couple of decent second hand amps and I will rewire all the speakers when I install them. I am thinking that I will probably install some JBL GTO speakers in the lower front doors. I have the GTO 609C's in my other car and I'm happy with the sound they put out. I am potentially thinking of running 2 amps, one for the Subwoofer and the rear speakers and then one for the 4 speakers in the front door. This will also give me a option of putting some speakers in the rear doors, but I think this won't really make much of a difference. When I started the install I thought, I'll just keep this really simple this time and not go overboard.

I'm going to install a second battery in the rear of the car, can you see any problem in running all the amps of the second battery? I already have an Enerdrive 40amp DC2DC charger that I am planning on using. I'm not planning on have the stereo cranked up where nots and bolts rattle themselves loose, I just want to be able to listen to music when on the freeway with windows open. I am seeing in the near future the need for an upgraded alternator.

Thanks again for all the replies.