[LRGPhD]

I've been searching the forum to try to answer this question myself, but it is probably something everyone on here already news.

I have the S674A Hi-Fi "Harman Kardon" and I'm wondering if it uses MOST. I'm doing a complete overhaul of the audio system and need to know if I'll need to buy a device like the Helix SMDI25 to bridge the HU to a DSP.

Sorry in advance for the dumb question!

[MarcoZandrini]

Your car's head unit outputs only analog signals. The head unit has a crappy digital to analog converter circuitry. You might look into the Audiotech-Fischer MATCH BMW 7UP amp. I installed one in my 2018 M240i. It's very tune-able. You can also install either a Bluetooth or a USB module in the amp.

[Encanto]

Originally Posted by MarcoZandrini

Your car's head unit outputs only analog signals. The head unit has a crappy digital to analog converter circuitry. You might look into the Audiotech-Fischer MATCH BMW 7UP amp. I installed one in my 2018 M240i. It's very tune-able. You can also install either a Bluetooth or a USB module in the amp.

There is no "crappy digital to analog circuitry" in the OEM HU, stop with the misinformation. You are the one with the crappy AUX to digital back to analog conversion in your own car.

[LRGPhD]

Originally Posted by MarcoZandrini

Your car's head unit outputs only analog signals. The head unit has a crappy digital to analog converter circuitry. You might look into the Audiotech-Fischer MATCH BMW 7UP amp. I installed one in my 2018 M240i. It's very tune-able. You can also install either a Bluetooth or a USB module in the amp.

Thanks! That's what I suspected.

[Encanto]

Originally Posted by LRGPhD

I've been searching the forum to try to answer this question myself, but it is probably something everyone on here already news.

I have the S674A Hi-Fi "Harman Kardon" and I'm wondering if it uses MOST. I'm doing a complete overhaul of the audio system and need to know if I'll need to buy a device like the Helix SMDI25 to bridge the HU to a DSP.

Sorry in advance for the dumb question!

There is no MOST hardware in the 2-Series audio systems however, you can code your OEM HU to output MOST as long as you run fiber optic cables from the OEM HU to the SMDI25. The dealer can sell you the OEM fiber optic cables and the terminations.

There is a thread in here of a member that did this MOST conversion, search for it.

[MarcoZandrini]

Originally Posted by Encanto

There is no "crappy digital to analog circuitry" in the OEM HU, stop with the misinformation. You are the one with the crappy AUX to digital back to analog conversion in your own car.

Really? Then why is it when I digitally send music to my car's Audiotech-Fischer MATCH BMW-7UP amp with the USB module the music sounds so much better than when I send the music digitally via the USB port in the console to the factory head unit? The reason: the head unit has mediocre DAC circuitry. Some DACs are better than others.

[LRGPhD]

Originally Posted by Encanto

There is no MOST hardware in the 2-Series audio systems however, you can code your OEM HU to output MOST as long as you run fiber optic cables from the OEM HU to the SMDI25. The dealer can sell you the OEM fiber optic cables and the terminations.

There is a thread in here of a member that did this MOST conversion, search for it.

Thanks!