Bose signal processing

[meicalnissyen]

We have all noticed how the sound changes when you crank it up.
the concensus is that the Bose system progressively cuts the bass as you go louder, presumably to save the speakers.

does anyone KNOW if this is done in the head unit or in the amp itself ???

 

[kvndoom]

Amp. I'm 99% sure of this, since my Mazda6 with bose did all the DSP in the amp. I got rid of the bose stuff and ran line level straight from the stock deck to my new amp and never got any weird effects, regardless of volume. I doubt that has changed, since I've read posts of people who just got rid of the bose amp and speakers, and were very happy with the remaining setup.

The only DSP the head unit does is ALC, and you won't need that once you get a new amp.

 

[meicalnissyen]

alright

Thanks

I was wondering to get a clean sweep or not. this means not, also means I am not constrained into 2ohm speakers (kappa)
amp shopping we go

 

[GoFast]

so a new amp and speakers are all thats needed? why all these complicated threads about how to make the stereo better if it is really that simple?

 

[meicalnissyen]

so a new amp and speakers are all thats needed? why all these complicated threads about how to make the stereo better if it is really that simple?

depends on how much you want to change out, rewire, etc

also, the natural assumption would be the HU having the dsp


the crummy shielded wire to the amp means you need to solder (well) rca's to the ends of the cable and cut up the factory harness (PIA) or run a LOC (worse)

runnin serious wire to the speakers big PIA
serious wire to amp PIA
warranty Q's comin into play about now

puttin a real sub in another can of worms


caps and chokes seem easy at this point
but a crossover only filters freqs, doesn't create what ain't there

 

[kvndoom]

so a new amp and speakers are all thats needed? why all these complicated threads about how to make the stereo better if it is really that simple?

Those threads are just improving what's already there on a budget (< $60). It upgrades the bose from unbearable to bearable, but little more.

When I can afford to drop over 500 dollars at once on the car (beside making payments (flash) ), the stock amp and speakers will be the first thing to go.

 

[Design]

We have all noticed how the sound changes when you crank it up.
the concensus is that the Bose system progressively cuts the bass as you go louder, presumably to save the speakers.

does anyone KNOW if this is done in the head unit or in the amp itself ???

Responded to your PM. The signal processor is within the amp, according to Bose documentation:
http://www.bose.eu/EU/en/Images/Syst_Mazda3_facelift_e_150_tcm42-8159.pdf

I don't think anyone has measured the signal quality from the HU, but in theory it is supposed to be flat and low level. A simple RCA conversion should do the trick.

I have not personally seen or performed this type of install (I will be doing my own MS3 GT late this year). But I have talked to enough owners online and in person to be confident in this type setup without a complex LOC.

 

[meicalnissyen]

yeah,
I've taken the plunge.
hop I am happy when done

waiting on:
basslink2
phoenix gold ti6 front door
dayton 6.5 rear door
tang band tweet
doodads to do 2nd order passive 3.6K front 1.9K rear
4ch amp highpass at 400 front and 125 back with pass thru to basslink
dymat for doors
on paper i have hope

I MAY get a cap I will use all stock wiring. I have no intention of ripping the interior apart runwire and fight whine. this is the one and only place a cap can help

more to come

 

[Design]

yeah,
I've taken the plunge.
hop I am happy when done

waiting on:
basslink2
phoenix gold ti6 front door
dayton 6.5 rear door
tang band tweet
doodads to do 2nd order passive 3.6K front 1.9K rear
4ch amp highpass at 400 front and 125 back with pass thru to basslink
dymat for doors
on paper i have hope

I MAY get a cap I will use all stock wiring. I have no intention of ripping the interior apart runwire and fight whine. this is the one and only place a cap can help

more to come

Very interested to see the results.

I think a few that have done this type of install used a ground loop isolator to weed out some excess noise in the system. Otherwise, sounds like a great setup!

 

[tubebrner]

Responded to your PM. The signal processor is within the amp, according to Bose documentation:
http://www.bose.eu/EU/en/Images/Syst_Mazda3_facelift_e_150_tcm42-8159.pdf

I don't think anyone has measured the signal quality from the HU, but in theory it is supposed to be flat and low level. A simple RCA conversion should do the trick.

I have not personally seen or performed this type of install (I will be doing my own MS3 GT late this year). But I have talked to enough owners online and in person to be confident in this type setup without a complex LOC.

Possibly a newb question. But how would I go about splicing the line level to RCA? I'm guessing take wire taps from the L+L- and R+R- before the Bose amp. But can I just cut off the ends of a standard RCA cable and tap into that? I'm not sure what the inside of RCA cables look like. Also would speaker wire or standard copper be used for the connection from the line level (pre-Bose amp) wires to the RCA cable?

 

[kiroro]

Any updates? wondering if the RCA method works

yeah,
I've taken the plunge.
hop I am happy when done

waiting on:
basslink2
phoenix gold ti6 front door
dayton 6.5 rear door
tang band tweet
doodads to do 2nd order passive 3.6K front 1.9K rear
4ch amp highpass at 400 front and 125 back with pass thru to basslink
dymat for doors
on paper i have hope

I MAY get a cap I will use all stock wiring. I have no intention of ripping the interior apart runwire and fight whine. this is the one and only place a cap can help

more to come

 

[meicalnissyen]

Any updates? wondering if the RCA method works

In fact I am feeling better enough to start pulling the door apart as I sit here, amp arrives today,, crossovers are made up.

THE BASSLIMK will NOT fit under the seat F!@#K so I hosed that part
dunno if I will sell it, or attempt a quick disconnect setup for it. but there is no way to hide it

the RCA method will work, the wires have been ID by other folk, the only question would be if I introduce a whine from the routing

 

[Kain]

I have a Basslink II and a basic Knukoncepts amp wiring kit going in this weekend. The plan is tapping the speaker lines on the input side of the amp. We'll see how it goes.

 

[meicalnissyen]

I have a Basslink II and a basic Knukoncepts amp wiring kit going in this weekend. The plan is tapping the speaker lines on the input side of the amp. We'll see how it goes.

where do you plan to mount the BL ?

 

[Kain]

Generally, the trunk, of course. Specifically, not sure yet. What I want to first figure out is what orientation sounds best acoustically (laying horizontal or standing up, facing the rear or sideways) then think about mounting from there. I played around with the idea of bolting it to the 40 side of the 60/40 rear seat, but then it might get in the way of the anchor for a baby seat.

 

[meicalnissyen]

In fact I am feeling better enough to start pulling the door apart as I sit here, amp arrives today,, crossovers are made up.

THE BASSLIMK will NOT fit under the seat F!@#K so I hosed that part
dunno if I will sell it, or attempt a quick disconnect setup for it. but there is no way to hide it

the RCA method will work, the wires have been ID by other folk, the only question would be if I introduce a whine from the routing

Door speakers are installed, that went OK, Soo Frigggin hot out there. Dynamated the doors a bit, then stuffed em with fiberglass some. I have a tiny buzz on the driver latch to eradicate (that crap I am hypersensitive to, buzzes drive me nuts)
tweets are not quite perfect fits in the sails, I got some fairly large tangband tweets, but they should drop in easy enough. I will likely do the sail panel mod later on.

damn amp RE ship arrives monday, they sent the wrong model first time

 

[meicalnissyen]

Door speakers are installed, that went OK, Soo Frigggin hot out there. Dynamated the doors a bit, then stuffed em with fiberglass some. I have a tiny buzz on the driver latch to eradicate (that crap I am hypersensitive to, buzzes drive me nuts)
tweets are not quite perfect fits in the sails, I got some fairly large tangband tweets, but they should drop in easy enough. I will likely do the sail panel mod later on.

damn amp RE ship arrives monday, they sent the wrong model first time

complete. see the how to