most Using MOST audio decoder & integrity of MOST system

[Shorty0123]

Hi all, I want to bypass the toyota amplifier completely and i want to hijack the MOST signal to obtain the line level audio, hence lookint at the aftermarket decoders... however i want to do this without affecting the integrity of the other MOST bus systems... Is there a sensible place to insert the decoder in the loop and does this break the MOST loop, i.e anything upstream of the thrid party adapter wont work? If this is the case is it possible to split the most signal? im assuming this is a fiber optic connection?

 

Thanks in advance, im betting @chris.ac knows the answer

 

Ive attached a screenshot of a device that can be used to convert to non OEM headunits, but there are devices that hijack the MOST fiberoptics and output just the analog audio signal

 

[Chris.ac]

Not sure to understand the point. 

This kit is to enable a non oem unit to connect to the oem amplifier. 

 

If you are bypassing the amplifier, you don't need this kit.

 

Maybe state what it is exactly you are trying to do? 

 

If you want to use the connections to the oem speakers directly, the sockets at the amplifier are wired like this. 

 

 

If you want to see the block diagram for how the most system connects to the sub-components, use this file

 

Headunit block diagram.pdf

[Shorty0123]

Hey Chris, yeah i know how to get a high level signal from the amp, ive designed a car amplifier which ive built with DSP enabled circuits (i design and build speakers and amps in my spare time) and i do indeed want to use all of the existing speaker connections and will be hijacking those from the oem amp plugs. Id rather not keep the amplifier 'live' just so i can get a line level signal. And instead remove it so i can place my new amp gear. I was rather hoping i could just insert a box that extracts the signal from the canbus out to a couple of RCAs, i didnt include a pic of the device in question as id found it on AExpress the previous day but couldn't find it for the life of me later when i penned this post (defo exists tho) it essentially takes a fiber connection and outputs just two RCAs, they are plenty on AExpress that do Mercs/Audi etc, this specific one was for Toyota however... I'll have another search... But in the meantime I'll include an image of the merc one. 

 

What i was concerned about was if i used such a device and being that it only has a single fiber input, I'll be breaking the canbus loop and may be stopping other elements working in the chain from the oem infotainment. I want to keep all of this working as i like the original equipment. 

 

Why am i bothering to do all of this? Because i want to tailor a dsp enabled listening experience in the car. 

Edited Friday at 07:07 AM by Shorty0123

[Chris.ac]

The 20 series doesn't use fibre optic, although aliexpress refer to it as an optical converter. 

 

Most doesn't use the canbus, it's a separate network. 

The headunit does all the work, so of you are replacing it, it's irrelevant if you are bypassing the amplifier.

 

That adaptor is used for aftermarket headunits to convert their analogue outputs into a most signal to the amplifier. 

 

If you are removing the headunit and amplifier, you don't need that converter

[Shorty0123]

Thanks, i see. But I'm not removing the headunit. I'm keeping the toyota one. I'll just carry on with the high level converter then if there's no other option. Thanks again

[Chris.ac]

I don't think I've seen an adaptor that takes  the MOST signal from the headunit and converts to an rca.

 

The closet i have seen is an amp bypass adaptor, or the converter you linked that allows you to retain the amplifier (both assume headunit replacement)

The other auxiliaries like auto parking and cameras and rear screen use GVIF ( gigabit video interface)

 

There must exist an adaptor that converts most to RCA, maybe another Toyota model?

[Shorty0123]

Well thats what i would assume also... If theres an adapter that encodes, there must be a decoder. Just feels like high/low level adapters are not a very elegant solution. What i want to achieve is to get a driver focused, banging system that suits my 53 yo compromised ears that also employs a clever loudness setting for lower volumes. 

 

Ive replaced the front door speakers and dynamatted the panels, and the dashboard speakers. Ive built a separate compact sealed 10inch sub and amp and it's starting to sound a lot better... Just wanna improve further. 

 

I dont want to change the headunit as i feel all original is best, bluetooth works well and ive digitised loads of CDs onto the HDD, i ise a small add on android auto screen and its fine. Just wanna get that sound spot on.

 

The factory 18 speaker system is good, but not good enough for my tastes. 

 

I'll keep looking...