e90 sedan door mount 6-8" midbass

ctuna · 06-16-2023, 02:38 PM

If you have the idrive Logic 7 system you are s****wed for retrofits.
(without burning 100's of dollars)
You could investigate the OEM Evo NBT upgrades.

Peter Morrin · 06-22-2023, 11:50 AM

OK, Perhaps this is the point of opening the discussion.

I have read Ctuna's referenced posts and am still a little confused about the implications of re-programming my Professional Head Unit (Not I-Drive) from Top Hifi to Hifi:

Do I remove the L7 amplifier and insert a MOST connector in its place?

Will the in-trunk CD changer on the MOST network still work? Can I substitute the CD changer for some form of USB converter like Mr. 12V to get USB access? If I can, where is the Digital to Analogue conversion made? In the original system, I presumed it was done in the L7 Amplifier.

Where do I connect to the low level, full-ranged, flat / unprocessed, balanced differential outputs from the re-coded Professional Head Unit? I would want to connect them to a DSP mounted in the current location of the L7 amp?

Are all stand alone DSP able to receive these signals or only some? I know there was a caution that only some amplifiers could receive these signals. Once these signals are processed by the DSP, can any quality, old school amplifier be used? I have some from Alpine, ADS, Harmon Kardon, and Precision Power.

Does Recoded to HIFI>Analogue Signal>DSP>Analogue Signal>Amplifier equal Professional Head Unit>MOST Digital Output>DSP/AMP in terms of sound quality?

ctuna · 06-22-2023, 10:07 PM

If are leaving the L7 amp behind then you program for Hi Fi.
You can put a most jumper in the L7 amp loop if you don't want
go to the trouble of rerouting the wires at the Most Hub so anything
left on the Most Loop is Intact.

The BMW Head unit when programmed for Hi Fi output a 5 volt differential
signal which is a good analog pre amp signal . Basically this is a reduced speaker
out signal with no common ground. Most of the Better amps and DSP accept this
signal with no problems. However you should check with the manufacturer to
be sure.

If you buy a quality dsp/amp it will be better than the logic 7 system if
you can deal with installing and tuning it.
Technic makes a harness kit for getting rid of the Logic 7 amp .

06-16-2023, 02:38 PM	#45
ctuna Lieutenant General 1920 Rep 13,121 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	If you have the idrive Logic 7 system you are s****wed for retrofits. (without burning 100's of dollars) You could investigate the OEM Evo NBT upgrades.
	Appreciate 0 Quote

06-22-2023, 11:50 AM	#46
Peter Morrin Private First Class 47 Rep 157 Posts Drives: 2007 E90(sedan) 328xi Join Date: Dec 2021 Location: Kingston, Ontario, Canada iTrader: (0)	OK, Perhaps this is the point of opening the discussion. I have read Ctuna's referenced posts and am still a little confused about the implications of re-programming my Professional Head Unit (Not I-Drive) from Top Hifi to Hifi: Do I remove the L7 amplifier and insert a MOST connector in its place? Will the in-trunk CD changer on the MOST network still work? Can I substitute the CD changer for some form of USB converter like Mr. 12V to get USB access? If I can, where is the Digital to Analogue conversion made? In the original system, I presumed it was done in the L7 Amplifier. Where do I connect to the low level, full-ranged, flat / unprocessed, balanced differential outputs from the re-coded Professional Head Unit? I would want to connect them to a DSP mounted in the current location of the L7 amp? Are all stand alone DSP able to receive these signals or only some? I know there was a caution that only some amplifiers could receive these signals. Once these signals are processed by the DSP, can any quality, old school amplifier be used? I have some from Alpine, ADS, Harmon Kardon, and Precision Power. Does Recoded to HIFI>Analogue Signal>DSP>Analogue Signal>Amplifier equal Professional Head Unit>MOST Digital Output>DSP/AMP in terms of sound quality?
	Appreciate 0 Quote

06-22-2023, 10:07 PM	#47
ctuna Lieutenant General 1920 Rep 13,121 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	If are leaving the L7 amp behind then you program for Hi Fi. You can put a most jumper in the L7 amp loop if you don't want go to the trouble of rerouting the wires at the Most Hub so anything left on the Most Loop is Intact. The BMW Head unit when programmed for Hi Fi output a 5 volt differential signal which is a good analog pre amp signal . Basically this is a reduced speaker out signal with no common ground. Most of the Better amps and DSP accept this signal with no problems. However you should check with the manufacturer to be sure. If you buy a quality dsp/amp it will be better than the logic 7 system if you can deal with installing and tuning it. Technic makes a harness kit for getting rid of the Logic 7 amp .
	Appreciate 0 Quote