Solving “bright” speakers
Discussion
Hi, didn’t have much luck on the other forum so thought I’d try here instead.
My old Range Rover p38 has a Harmon Kardon stereo fitted. Each door has its own amplifier with a built in crossover for low vs mid range, there's also a tweeter running off the mid driver, with a capacitor to presumably filter out the lower frequencies. I've changed the low and mid range speakers with quality replacements, but it doesn't sound right, it's too "bright" and there's not enough bass. I'm thinking of fitting a separate crossover so would like to "combine" the signals from the door amplifier. Is it simply a case of connecting the split positive and negative feeds going to the speakers, and feeding these into a crossover? I'd prefer not to blow the amp(s) up.
The other thing I was going to try is disconnecting the tweeters to see if that makes any difference. Looking for ideas really on how best to adjust the output from amps with active crossovers built in. I could rip the whole lot out but it’s a decent system and I’d prefer to keep as much original as I can.
These are the speakers I used, except I kept the original HK tweeters for the sake of appearance
https://www.focal.com/uk/car-audio-kits-solutions/...
Thanks.
My old Range Rover p38 has a Harmon Kardon stereo fitted. Each door has its own amplifier with a built in crossover for low vs mid range, there's also a tweeter running off the mid driver, with a capacitor to presumably filter out the lower frequencies. I've changed the low and mid range speakers with quality replacements, but it doesn't sound right, it's too "bright" and there's not enough bass. I'm thinking of fitting a separate crossover so would like to "combine" the signals from the door amplifier. Is it simply a case of connecting the split positive and negative feeds going to the speakers, and feeding these into a crossover? I'd prefer not to blow the amp(s) up.
The other thing I was going to try is disconnecting the tweeters to see if that makes any difference. Looking for ideas really on how best to adjust the output from amps with active crossovers built in. I could rip the whole lot out but it’s a decent system and I’d prefer to keep as much original as I can.
These are the speakers I used, except I kept the original HK tweeters for the sake of appearance
https://www.focal.com/uk/car-audio-kits-solutions/...
Thanks.
Edited by anonymous-user on Tuesday 10th October 08:25
Thank you, I thought the question would be better suited to this section. Any suggestions what amp would work well with the Focals? Doors each have a bass and mid driver whilst the font also has tweeters and there’s a (frankly useless) sub in the boot. I’m not a fan of hacking away at wiring if it can be avoided. Just want a nice, natural sound. I’m guessing it’ll also need a new head unit?
Edited by anonymous-user on Tuesday 10th October 15:45
TEKNOPUG said:
Focal make a range of amps but anything with a decent 2 channel output ~100w RMS from a reputable brand like Audison, Hertz, Alpine, JL Audio, Pioneer etc. Think about location and size constraints when choosing.
You'd need to run power and earth to the amp and RCA and accessory from the HU. Then a pair of speaker wires to the crossovers (presumably in the doors). You can probably leave all the original wiring and amps if there is space.
You could keep your existing HU. I don't know whether it's Clarion or Alpine but there will probably be a ISO wiring harness available to connect an amp or you can use a line level converter. I expect Focal do one (at a price) but they are widely available. They convert a speaker out to RCA. All depends on which HU you have. Obviously switching to modern HU will give you greater format options and tuning.
You could also easily fit a replacement sub such as a Focal ISUB.
Determine your budget and goal first so you avoid buying and installing twice.
Thanks, the original HU is by Alpine and has 70 ohm output so probably easier to replace. I’ve got a Grom adapter for it which converts the CD changer input to USB and Bluetooth, which is quite clever, but I guess I can sell that on. I guess with the right attenuator it would be possible to further reduce the current speaker output to RCA then into a 4 channel amp ? You'd need to run power and earth to the amp and RCA and accessory from the HU. Then a pair of speaker wires to the crossovers (presumably in the doors). You can probably leave all the original wiring and amps if there is space.
You could keep your existing HU. I don't know whether it's Clarion or Alpine but there will probably be a ISO wiring harness available to connect an amp or you can use a line level converter. I expect Focal do one (at a price) but they are widely available. They convert a speaker out to RCA. All depends on which HU you have. Obviously switching to modern HU will give you greater format options and tuning.
You could also easily fit a replacement sub such as a Focal ISUB.
Determine your budget and goal first so you avoid buying and installing twice.
paralla said:
wormus said:
TEKNOPUG said:
Focal make a range of amps but anything with a decent 2 channel output ~100w RMS from a reputable brand like Audison, Hertz, Alpine, JL Audio, Pioneer etc. Think about location and size constraints when choosing.
You'd need to run power and earth to the amp and RCA and accessory from the HU. Then a pair of speaker wires to the crossovers (presumably in the doors). You can probably leave all the original wiring and amps if there is space.
You could keep your existing HU. I don't know whether it's Clarion or Alpine but there will probably be a ISO wiring harness available to connect an amp or you can use a line level converter. I expect Focal do one (at a price) but they are widely available. They convert a speaker out to RCA. All depends on which HU you have. Obviously switching to modern HU will give you greater format options and tuning.
You could also easily fit a replacement sub such as a Focal ISUB.
Determine your budget and goal first so you avoid buying and installing twice.
Thanks, the original HU is by Alpine and has 70 ohm output so probably easier to replace. I’ve got a Grom adapter for it which converts the CD changer input to USB and Bluetooth, which is quite clever, but I guess I can sell that on. I guess with the right attenuator it would be possible to further reduce the current speaker output to RCA then into a 4 channel amp ? You'd need to run power and earth to the amp and RCA and accessory from the HU. Then a pair of speaker wires to the crossovers (presumably in the doors). You can probably leave all the original wiring and amps if there is space.
You could keep your existing HU. I don't know whether it's Clarion or Alpine but there will probably be a ISO wiring harness available to connect an amp or you can use a line level converter. I expect Focal do one (at a price) but they are widely available. They convert a speaker out to RCA. All depends on which HU you have. Obviously switching to modern HU will give you greater format options and tuning.
You could also easily fit a replacement sub such as a Focal ISUB.
Determine your budget and goal first so you avoid buying and installing twice.
Your second sentence makes sense though and clearly what we have here are a bunch enthusiastic amateurs. I’ll go elsewhere.
Edited by anonymous-user on Thursday 12th October 12:46
TEKNOPUG said:
paralla said:
You don't have enough knowledge to comprehend advice being given on here. Take the car to a professional installer and get them to sort it out.
A little knowledge is a dangerous thing 
paralla said:
Because you said your head uinit "has 70 ohm output". The rating of the head unit output is measured in Watts rather than Ohms.
Because you said "with the right attenuator it would be possible to further reduce the current speaker output to RCA ". A line output converter is the device that does that.
These couple of seemingly small but important misunderstandings demonstrate that you are better off getting someone else to do it for you.
I meant 70 ohm (output) impedanceBecause you said "with the right attenuator it would be possible to further reduce the current speaker output to RCA ". A line output converter is the device that does that.
These couple of seemingly small but important misunderstandings demonstrate that you are better off getting someone else to do it for you.
I guess the output converter would do the same job as an attenuator, but I cannot find one that will work at 70 ohm impedance to RCA.
From this article about the “attenuator” needed:
https://www.rangerovers.net/attachments/ray-ambler...
document said:
Introduction
Owners who want to install an aftermarket stereo head unit wth more modern capabilities in their 1995-2002 Range Rovers are frustrated by the fact that
most replacement head units are incompatible with the rest of the Range Rover stereo system -- namely the built-in amplifiers that drive the multitude of speakers, and the steering wheel controls. Ray Ambler, a Rangerovers.net member, has pioneered the process of interfacing these aftermarket units and has kindly provided the information on this page for making the built-in P38 stereo amplifiers and steering wheel controls work with any head unit. Ray's solution allows you to use the built in amps on a standard high level output from basically any stereo head unit!
Technical Background
The input impedence of the Range Rover's Harmon Kardan door amplifiers is approximately 70 ohms. This is why when you drive them with the full output from the usual aftermarket head (with an output impedance of 4 to 8 ohms) the volume has to be kept low. The "low power" original Alpine unit has an output impedence of about 70 ohms and this is what confuses most installers. When you use the line out feeds (1000 ohms or above) you will get hissing / interference or just low volume.
To solve this problem, you need to create an attenuator capable of giving a suitable load to the head unit, provide matching to the door amps and reduce the audio level by 20dB. Easily done with a pi or T attenuator. Remember that the attenuator has to handle the power from the head unit. In my case I tested the head unit into a 16 ohm load and it was fine. This means that full volume only requires the attenuator to handle about 2 watts making it small and easy to build using 1 watt resistors in series / parallel configuration. Remember to use carbon or metal film components, not wire wound or you will produce undesirable inductive loading.
Hth Owners who want to install an aftermarket stereo head unit wth more modern capabilities in their 1995-2002 Range Rovers are frustrated by the fact that
most replacement head units are incompatible with the rest of the Range Rover stereo system -- namely the built-in amplifiers that drive the multitude of speakers, and the steering wheel controls. Ray Ambler, a Rangerovers.net member, has pioneered the process of interfacing these aftermarket units and has kindly provided the information on this page for making the built-in P38 stereo amplifiers and steering wheel controls work with any head unit. Ray's solution allows you to use the built in amps on a standard high level output from basically any stereo head unit!
Technical Background
The input impedence of the Range Rover's Harmon Kardan door amplifiers is approximately 70 ohms. This is why when you drive them with the full output from the usual aftermarket head (with an output impedance of 4 to 8 ohms) the volume has to be kept low. The "low power" original Alpine unit has an output impedence of about 70 ohms and this is what confuses most installers. When you use the line out feeds (1000 ohms or above) you will get hissing / interference or just low volume.
To solve this problem, you need to create an attenuator capable of giving a suitable load to the head unit, provide matching to the door amps and reduce the audio level by 20dB. Easily done with a pi or T attenuator. Remember that the attenuator has to handle the power from the head unit. In my case I tested the head unit into a 16 ohm load and it was fine. This means that full volume only requires the attenuator to handle about 2 watts making it small and easy to build using 1 watt resistors in series / parallel configuration. Remember to use carbon or metal film components, not wire wound or you will produce undesirable inductive loading.
The sound coming from bass and mid speakers is plenty loud enough. Crank it up and it’ll make your ears bleed, no distortion either, it’s just the sound at high volume is a touch bright for my liking, hence asking the original question.
Edited by anonymous-user on Thursday 12th October 13:58
Bit of an update. I mentioned earlier I've got a Grom USB 3 bluetooth adapter: https://www.gromaudio.co.uk/products/grom-usb3-usb...
It plugs in the back of the stereo in place of the CD changer as an input source. Well, I just plugged the CD back in and played a few tunes. Hey presto, it sounds loads better with loads of bass, it sounds nice, even played loud. So I've saved a lot of money buying new random components. Time for a rethink.
It plugs in the back of the stereo in place of the CD changer as an input source. Well, I just plugged the CD back in and played a few tunes. Hey presto, it sounds loads better with loads of bass, it sounds nice, even played loud. So I've saved a lot of money buying new random components. Time for a rethink.
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