1996 LS400 AUDIO UPGRADE OPTIONS

[Howplum]

Being of a certain age I have discovered a radio station aimed at my age group, Boom Radio. However, it is only available on DAB+ and the internet. That apart, I have noticed that on long journeys the FM signal can be variable.

I have tried a cassette adapter which lasted no time at all before it decided to keep self ejecting, even after watching a YouTube video and removing most of the few innards there are.

I then tried a cheap Bluetooth FM transmitter that relays the transmission from my phone through the radio (87.5). This plugs into the lighter socket but the sound quality was very poor. Looking at reviews for dedicated DAB+ adaptors, such as Kenwood, Pure et al, the weakness seems to be the poor quality of sound when using the FM radio, although when connected via an auxiliary socket the sound was very good.

My fall back option at the moment is to use a small Bluetooth speaker on top of the dashboard, but that would not exactly be discreet.

However, does anyone know if it possible to adapt the existing stereo to include an auxiliary socket and/or a USB socket? Does this sacrifice the cassette facility perhaps?

 

[Howplum]

After a bit more digging I found this article:

https://www.clublexus.com/forums/lexus-audio-video-security-and-electronics/269156-how-to-build-and-hardwire-an-auxillary-input-to-oem-stereo.html

It's obviously for US cars and I'm not sure what the acronym NAK stands for. Something to do with navigation perhaps?

If I understand correctly the CD changer is bypassed when a device is plugged into the auxiliary socket, although the amplifier is none the wiser. Following that logic, the device would presumably have to be unplugged for the CD player to work.

Any thoughts?

[runsgrateasanut]

That would be the Nakamichi sound system an alternative to standard unit.  Here's a link which I've not read so may not be helpful.   I'm likely to replace either the LS or the GS with a modern unit with Aux in a plastic Surround which has sat for several years on my shelf. Can't be bothered with trying to botch an aux input.

https://us.lexusownersclub.com/forums/topic/1419-nakamichi-stereo-vs-standard-unit/

 

[Howplum]

Thanks Stuart. I need to check and see which unit I have.

In the meantime, I wonder if it is possible to fit an aftermarket head unit with an auxiliary socket? I suspect not.

[runsgrateasanut]

I have a new Sony CDX-GT45OU which has an aux and USB slot. It's old Hat by todays double Din type units that I suspect most people would fit.  With the early LS400 there is no seperate Amplifier.  With the GS300 there is an Amplifier which complicates matters.  I suspect your later LS also has a seperate Amplifier? 

This video may give you some help in deciding if to make the switch?  https://www.youtube.com/watch?v=-59WBq3DshY

 

 

[runsgrateasanut]

ps the Sony covers AAC and MP3 (which I recorded most of my music on to).  It also has a single CD changer and the Amplifier is internal - or that's my understanding.  Can get a linking Connector Harness to original connectors but need to carefully check that they are right.

[Howplum]

Thanks Stuart. I will obviously need to investigate further.

 

[Cels1or]

I did in my 350z take apart the original stereo and soldered an aux cable onto the input for the cassette deck not sure if something similar could be done. I did it for the pure cost of swapping out the original stereo as it was a bose unit with separate amplifier. I shall see if I can find a walk through, I'm unfamiliar with the innards of your particular stereo.

[Howplum]

Thanks Aaron. That could be a plan too. 

[BigBoomer]

I am using a Bluetooth module that plugs into the back of my Mark Levinson system on my LS430 that works great and sounds superb.
They sell them with both the 6+6 and 5+7 Lexus adapters but I have no idea if yours even has those.
I have seen the Nakamichi with an Aux-In connector as one of the LS400s I looked at (a 2000) had it fitted.

 

[Howplum]

My stereo appears to be the standard Lexus one, as per the enclosed picture (dodgy climate control display now replaced):

I have also found a wiring diagram in my Repair Manual:

Anyway, piggy backing the cassette outputs sounds like a less complicated option, provided I can establish which wires they are!

 

 

 

 

 

 

 

[Howplum]

And this a cropped version showing the radio/cd player connections.

Any help would be appreciated.

 

[Malc]

29 minutes ago, Howplum said:

(dodgy climate control display now replaced)

can you tell me more about this please ............  mine is getting that way too

thanks

Malc

[MJB18]

Many years ago, when I had my LS400, I bought one of these.

It connects in line with the aerial lead, rather than transmitting over FM. There's DIP switches to select which frequency it feeds into the radio.

Apparently it switches off when it doesn't detect anything on its audio input, so becomes transparent as far as the normal radio signal in concerned.

I'd forgotten I had it until I read this post. I didn't get around to fitting it so it's never been used, and I don't even know if it works.

I don't know where you are in Bucks, but you're welcome to it if you want!

[Howplum]

11 minutes ago, Malc said:

can you tell me more about this please ............  mine is getting that way too

Malc,

All I did was buy the complete console, including the radio, from a breaker on eBay. I did do a "How to" tutorial which is on here somewhere on how to replace it.

I subsequently sold the radio on, but now wish I hadn't, because I could have used it as a guinea pig.

Mick,

Thank you very much for the offer. I might take you up on that. I have no idea how it might work, but I see it is JVC, so hopefully the instructions will explain all. I'm in Bletchley, but I will PM you.

[Howplum]

Thanks to Mick's very kind offer I installed the JVC FM Modulator this afternoon, and it works. However, there is a small issue I wondered if someone might be able to help me with.  There is some background noise which seems to be present on all the 8 channel options that the device communicates on.  The frequencies on FM range from 88.10 MHz to 89.50 MHz in 200 kHz increments. With no device connected to the modulator I can get radio reception on all of the 8 channels, albeit not very well, but with the background noise, possibly because reception is weak.

The modulator is fitted inline with the aerial and I assume is intended to automatically override any signal from the aerial when a device is connected to the modulator.  Similarly, when an external device is not present the modulator effectively becomes "invisible". I must admit this is outside my comfort zone, but it seems to me that some form of signal is still getting through.

I have noticed that FM Modulators are still available, although none of them are automatic, so they incorporate an on/off switch.

Any thoughts would be appreciated.

[Howplum]

I should add that the background noise is present without the engine running.

[Cotswold Pete]

On 11/29/2021 at 5:20 PM, Howplum said:

I should add that the background noise is present without the engine running.

Is the noise a hiss like white noise or more like pink noise, or is it some kind of warbling.

Any chance you could capture the noise on mobile phone and put MP3 file up here.

Does sound odd that it happens when engine off, but possible that some electronics in the is still sending junk up the voltage rails which the FM head end (or the FM modulator) is picking up.

The pioneer unit is not the quietest in terms of it's noise floor, but I only notice this when stationary and quiet music (really quiet) and volume cranked up.  

[Howplum]

The noise is a constant tone, and is present even with engine off and the external aerial disconnected.

This is a recording:

2021_12_01_11_11_40

It seems to me the issue might be with the FM modulator itself. Apparently it has been sitting in a cupboard for over 10 years, although I can't see how that might affect it.

[Cotswold Pete]

39 minutes ago, Howplum said:

The noise is a constant tone, and is present even with engine off and the external aerial disconnected.

 

Under headphones I can hear what sounds like hiss, with a very (very) slight break-in from an actual FM channel.

The hiss implies the Pioneer is seeing an FM signal but nothing to really tune into so it just plays noise.  It could be the modulator is at fault, but without a scope not too easy to know.  

Maybe try the modulator on the Home stereo tuner which will be a bit of a pain because of different connectors and 12volt. 

What DAB unit are you using, I use a Sonichi S100 (but not sure if it is Dab+) it was useless via casette adaptor, but fine via it's own FM transmitter with external aerial.  (Make sure you have a high quality USB adpator in the cigarette lighter - some inject noise into the FM system)

[Howplum]

Thanks for your comments Pete. To be honest it was only on a whim that I thought I could add an auxiliary input so that I could listen to one particular radio station (Boom) through my phone, or perhaps my music library from an ipod.

As I mentioned before, I have tried the cassette adapter and a plug-in FM Transmitter, both of which didn't produce the desired result or quality.

Veba seem to most common of this type of device and gets reasonably positive reviews on amazon, for example, but I get the impression that all these devices are a bit of a compromise, perhaps with predictable results.

Another issue I haven't mentioned is that when travelling any distance the radio doesn't automatically seek the strongest signal for the chosen station, although I'm not sure if it supposed to or not.

I think for the moment I am tempted to live with the existing system.

 

[Cotswold Pete]

14 hours ago, Howplum said:

all these devices are a bit of a compromise

My thoughts exactly

[BigBoomer]

Anything that passes your audio signal via the cassette or FM tuner is going to reduce the quality.
It all depends on your tolerance for the reduction in quality.

I ran with a cassette adapter for a few months but it made the music sound flat, and there was the constant background noise of the cassette mechanism turning.
Then I got a Bluetooth-FM adapter which I used for a couple of years which was OK, but had a quiet hum in between songs and occasional dropouts when the FM signal got swamped by something else. On one occasion I got to hear someone else's music for about 3 minutes when stuck in the Dartford Crossing traffic jam. I assume they were also tuned to 108.0Mhz and had a more powerful FM transmitter than mine which was plugged in inside the armrest.

The Bluemusic Bluetooth receiver I now have fitted to my LS430-ML system has excellent sound quality and usability, but requires either the 6+6 or 5+7 connector layout, which you don't have in the 95-97 LS400 Nakamichi systems

The best option w.r.t. audio quality I have seen for your radio would be to get a working spare unit and send it to the US to get a 3.5mm Aux input socket added to it. Either that or else have a highly competent aftermarket radio installer fit an aftermarket unit. There are no harnesses available for it, so they will have to create their own, but the really good (and expensive) ICE people know how to do it.

[Howplum]

I had another look at the procedure for adding an auxiliary input shown in the link in my original post, which involved hard wiring, as opposed to some sort of adaptor. Originally I thought that doing this sacrificed the CD player, but I now realise that by using 5 pin relays, as opposed to 4 pins, it doesn't. It becomes a switchable alternative source.

My knowledge of electrics is pretty basic, but it looked perfectly feasible, with care.

However, the wiring colours and the connector plug are for US specification cars, as is the electronic repair manual I have, none of which agree with what is actually on my car, which has the original Pioneer head unit.

I established that the grey connector to the amplifier is for the CD changer by the simple process of systematically unplugging the connectors to see what didn't work.

Although there are 14 slots in the connector, only 6 are used, and they are:

Top row (L - R):

1 - Green/black 

2 - Green/red (or brown?)

4 - Brown/yellow

5- Brown/white

Bottom row (L - R):

12 - Green

13 - Purple

It's possible that 1 & 2 and 4 & 5 are paired, due to the colouring of the wires, but I'm hoping someone on here has access to the correct (non - US) wiring diagram and can tell me the specific assignation of each of these wires. What I need to know is the speaker channels, i.e. R+, R-, L+ and L-.

Many thanks.

 

[hockeyedwards]

I hope I remember this thread, a lot of interesting points. I won't be getting round to mine until the new year, finally secured a workshop and need to kit it out for the LS restoration. I do have a friend who specialises in audio upgrades/ modifying etc. I can only apologise I won't have any insight until Jan/ Feb time. I also have a spare radio as a trial piece/ spare parts should we make any errors.

Currently using a casette Bluetooth adaptor for my own music, but the guy I bought it off left 6 CD's in the changer, ranging from Metallica to Golden Era Hip Hop. I look quite the 'white gangster'... haha!