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Discussion Starter · #1 ·
So in my never-ending quest for audio nirvana, I'm slowly-but-surely replacing the Bose audio system in my Gen 2 2016 LT (I only got Bose since it's what the dealer had on order) with something much higher end.

I need to figure out what size the tweeters are, as well as the size of the midrange in the center of the dash.

If anyone can help me out here, I'd really appreciate it!

Here's what I know so far...

Doors: Stock speakers are 6.5" paper drivers (most likely the same as gen 1) with the same brackets as Gen1
Rear Doors: Same as front doors. Drivers have a different look to the dust cap, with plastic instead of paper, which is likely a whizzer to reproduce some highs. This seems to have almost no effect on the high frequency output, with no discernable HF output

Tweeters: Haven't been able to pop open the dash to look at these babies, but they don't sound great. Definitely harsh, with a high 3rd harmonic component. Will be replacing these as soon as humanly possible.

Midrange: Also haven't been able to look at this, most likely a 2-3" driver. Will be replacing this as well.

Subwoofer: Is an 8" paper driver housed in a fairly resonant plastic enclosure. I already put a lot of mass-loaded vinyl in there, and some studio foam to dampen the resonances. Worked WONDERS, but will be replacing the sub soon. Most likely with a Dayton Reference series, as it seems like the enclosure will have the proper loading for that driver.

I'll be replacing the Bose Amp, wiring to/from the Head Unit, and the wiring to the doors, speakers, tweeters, and midrange with some nice 14/2 that'll handle a LOT more current than the 18AWG (maybe even 20AWG?) that's currently there.

I'll be running everything through an 8-channel audio interface connected to an Intel NUC which will process the audio with DSP/FIR filters/Convolution to correct the frequency response, timing/amplitude, and impulse response.

Also, pleasant surprise: the mylink radio supports WAV files up to 24bit/192khz!!! this is a welcome improvement!
If only they had FLAC support. Oh well...

Just wanted to share this info since I haven't been able to find any yet, maybe it'll help.
 

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This is interesting info. Do you have any pictures of the drivers? Does the factory amp individually power each driver? I know bose tends to shy away from crossovers, choosing to have individual channels and DSP-based crossovers prior to the amp. Is the sub vented, sealed, or some other method (waveguide , bandpass etc)?
 

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For my crude ears, the Bose setup is OK, but your subwoofer housing improvement sounds like something even I could hear. Assuming I know nothing, how do I access the subwoofer location? What is mass-loaded vinyl? Will the usual fiberglass mat be good enough? Is the housing rigid enough? Thanks.
p.s. take pictures as you progress and compile a final write-up if you could.
 

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Bose car systems typically have a separate amp per speaker driver. They have always used electronic EQ, not necessarily DSP, to tweak the drivers and in the particular car they are installed in. No traditional passive crossover networks or filtering. I haven't taken mine apart yet. But as a (mostly) recovered audiophile, am always interested in such things.

The subwoofer is a bit boomy, but easy to tame with the bass control.

Paper cones are used in some very high end speaker systems. So don't discount them out of hand.

The whizzers in the rear seat drivers would make sense, since there are no separate tweeters. Common on wide-range drivers. They actually do help HF a bit, though you might need instruments to measure it. If you look carefully, there is probably some compliance to decouple the whizzer from the surrounding large cone.

Any idea how much depth you get to play with on the 6.5" drivers?
 

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On my Gen1 with the Bose system, I find the sound is very good when I use a good source - CD, or iPod on a well sampled track. But the whole thing sounds completely flat from regular FM.

I know the CD will be a lot better than FM, but I hear FM in other cars, especially my wife's C-Max Engeri, and it's very good from that car's system.

So I've concluded that the world's worst tuner is in our cars. I even wonder if my head unit is defective, and if I should try a warranty claim, because sometimes it can't pull in strong stations that aren't problems for other cars.

I was hoping the Gen2 would have had something better, and would have had HD-radio, at least as an option. But I'm actually happy with audio quality from the Bose setup - the punch and soundstage and clarity are very good with a good source, and even the bass is good, though not great.

-Lumos
2014 Gen1
 

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Bose car systems typically have a separate amp per speaker driver. They have always used electronic EQ, not necessarily DSP, to tweak the drivers and in the particular car they are installed in. No traditional passive crossover networks or filtering. I haven't taken mine apart yet. But as a (mostly) recovered audiophile, am always interested in such things.

The subwoofer is a bit boomy, but easy to tame with the bass control.

Paper cones are used in some very high end speaker systems. So don't discount them out of hand.

The whizzers in the rear seat drivers would make sense, since there are no separate tweeters. Common on wide-range drivers. They actually do help HF a bit, though you might need instruments to measure it. If you look carefully, there is probably some compliance to decouple the whizzer from the surrounding large cone.

Any idea how much depth you get to play with on the 6.5" drivers?
I agree with you. I have nothing against paper cones at all. I really like eliminating crossovers in the system too. I built some speakers using Audio Nirvana 10" full range paper drivers in a birch ply ported box. They sound absolutely fantastic...very much like a good electrostat. So I'm obviously bought into some of the advantages there.

I spent some time listening in my driveway the other night and came away rather impressed. For the money, it's a good buy. I think the most exciting sounding upgrade to me at this time is to add some mass damping to the sub cabinet. I'd like to think that will tighten it up a bit. Other than that, I'm pretty happy. I also call myself a recovered audiophile haha.
 

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On my Gen1 with the Bose system, I find the sound is very good when I use a good source - CD, or iPod on a well sampled track. But the whole thing sounds completely flat from regular FM.

I know the CD will be a lot better than FM, but I hear FM in other cars, especially my wife's C-Max Engeri, and it's very good from that car's system.

So I've concluded that the world's worst tuner is in our cars. I even wonder if my head unit is defective, and if I should try a warranty claim, because sometimes it can't pull in strong stations that aren't problems for other cars.

I was hoping the Gen2 would have had something better, and would have had HD-radio, at least as an option. But I'm actually happy with audio quality from the Bose setup - the punch and soundstage and clarity are very good with a good source, and even the bass is good, though not great.

-Lumos
2014 Gen1
I had the free trial of XM until yesterday and that is all I was listening to and it was the WORST sound I've ever heard. I'm used to having satellite radio in my cars and it being ok, not great, but it was awful. Everything sounded like it was coming through a tin can. I haven't really listened to FM yet, but if it's equally horrible I might be paying a visit to the dealer as well. Let me know how you make out if you go.
 

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I agree with you. I have nothing against paper cones at all. I really like eliminating crossovers in the system too. I built some speakers using Audio Nirvana 10" full range paper drivers in a birch ply ported box. They sound absolutely fantastic...very much like a good electrostat. So I'm obviously bought into some of the advantages there.
Off topic but which magnets did you use in your 10s? I've been wanting to try doing something with the Audio Nirvana FR drivers for a while now. I eventually want them for rear surrounds - to match my old Altecs up front. (Not going to pay 'collector' prices for vintage 755s...) Thinking more likely the 6.5" or 8" with Alnicos.

I spent some time listening in my driveway the other night and came away rather impressed. For the money, it's a good buy. I think the most exciting sounding upgrade to me at this time is to add some mass damping to the sub cabinet. I'd like to think that will tighten it up a bit. Other than that, I'm pretty happy. I also call myself a recovered audiophile haha.
It would be nice to figure out some easy ways of further quieting the cabin without adding significant weight.
 

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I had the free trial of XM until yesterday and that is all I was listening to and it was the WORST sound I've ever heard. I'm used to having satellite radio in my cars and it being ok, not great, but it was awful. Everything sounded like it was coming through a tin can. I haven't really listened to FM yet, but if it's equally horrible I might be paying a visit to the dealer as well. Let me know how you make out if you go.
Which channels were you listening to? Some are much better than others.
 

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Off topic but which magnets did you use in your 10s? I've been wanting to try doing something with the Audio Nirvana FR drivers for a while now. I eventually want them for rear surrounds - to match my old Altecs up front. (Not going to pay 'collector' prices for vintage 755s...) Thinking more likely the 6.5" or 8" with Alnicos.



It would be nice to figure out some easy ways of further quieting the cabin without adding significant weight.
I just went with the ferrite magnets. I am a believer that a low-displacement driver will not dramatically change based on magnet alone. I believe them that there are differences, but not ones I'd notice in my sub-optimal room. If I had a dedicated, sound treated room with perfect speaker placement, I may have sprung for Alnico or Nd. I have never regretted my choice.
 

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I can't say I've ever heard satellite radio, through any system (including very expensive stand alone "audiophile" tuners), and not found it beyond terrible. Generally, the better the system, the worse it sounds IMHO.
 

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Last I read, Sirius/XM use 128kbit compressed audio on their streams, probably on the mis-founded belief that its was CD Quality.

On my current car, only the comedy stations sound OK. All the music stations you can hear the compression artifacts pretty badly.
 

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Last I read, Sirius/XM use 128kbit compressed audio on their streams, probably on the mis-founded belief that its was CD Quality.

On my current car, only the comedy stations sound OK. All the music stations you can hear the compression artifacts pretty badly.
I thought it was more like 56-64 kbit based on AAC. But I could be wrong. It's been a while since I looked.
 

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I thought it was more like 56-64 kbit based on AAC. But I could be wrong. It's been a while since I looked.
It was a number of years ago, so I may be wrong, but it was an article discussing their satellite bit rate (which is different than their internet one), and that 128kb worked out better than FM, where the source started higher, but then was down-sampled several time prior to transmission.

And I will admit that this recollection was for Sirius in the pre-merger days...
 

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I've listened to Sirius/XM in about 15 cars now and it's never been remarkably bad before this.
 

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Discussion Starter · #17 ·
This is interesting info. Do you have any pictures of the drivers? Does the factory amp individually power each driver? I know bose tends to shy away from crossovers, choosing to have individual channels and DSP-based crossovers prior to the amp. Is the sub vented, sealed, or some other method (waveguide , bandpass etc)?
Sorry for the late reply, I've been busy these past few days.

Sub is in a ported enclosure. Find some pictures attached (it's all I have for now).

There are two amplifiers in there. One seems to be dedicated to the sub, and the other for the other 7 drivers.

I haven't seen any crossovers, but I'd guess it's all done via DSP, with the tweeters protected by a cheap bipolar capacitor to filter the lows just in case.



 

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Discussion Starter · #18 ·
For my crude ears, the Bose setup is OK, but your subwoofer housing improvement sounds like something even I could hear. Assuming I know nothing, how do I access the subwoofer location? What is mass-loaded vinyl? Will the usual fiberglass mat be good enough? Is the housing rigid enough? Thanks.
p.s. take pictures as you progress and compile a final write-up if you could.
Going through these and replying where I can.

You can get to the sub by removing the trunk floor, foam etc.
Then, you'll first need to pop off the white plastic panel directly behind the passenger-side rear seat, then unscrew the black knob on the trunk panel that covers the sub. You should then be able to remove the panel and access the sub.

Mass-loaded vinyl (MLV) is similar to dynamat, but weighs less and has similar performance. It also doesn't stink.
It dampens the low-frequency resonance of the plastic housing for the sub.
I did this because while the housing is "rigid" it is very lightweight and not acoustically "dead" by any measure.

Fiberglass mat would be useful to kill higher frequency resonances that the MLV doesn't.
I used 2" studio foam for this.

I also applied this treatment to the doors.

Before the treatment, the bass was so resonant and "boomy" that I had to turn the bass control on the head unit way down just to be able to listen to it, now it's much more refined, even with the stock sub. I can leave the bass eq in the center and it sounds nice and balanced.

I'll be taking more pictures as I progress.
 

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Discussion Starter · #19 ·
Bose car systems typically have a separate amp per speaker driver. They have always used electronic EQ, not necessarily DSP, to tweak the drivers and in the particular car they are installed in. No traditional passive crossover networks or filtering. I haven't taken mine apart yet. But as a (mostly) recovered audiophile, am always interested in such things.

The subwoofer is a bit boomy, but easy to tame with the bass control.

Paper cones are used in some very high end speaker systems. So don't discount them out of hand.

The whizzers in the rear seat drivers would make sense, since there are no separate tweeters. Common on wide-range drivers. They actually do help HF a bit, though you might need instruments to measure it. If you look carefully, there is probably some compliance to decouple the whizzer from the surrounding large cone.

Any idea how much depth you get to play with on the 6.5" drivers?
Yes, paper drivers are not necessarily bad. I just avoid them in car audio since they're more likely to be exposed to the elements/moisture/etc (especially in doors).

There isn't a ton of room to play with in the doors. I installed Focal K2 Power 165KR's in the front doors and Focal Performance coaxials in the rear doors. They're about 3-4" in depth, if that helps any. I believe there was maybe another two inches or so behind them to play with.
 

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This will probably be the only thing that I have that will be useful for your efforts.
This is because the input side of the Volt audio system is all MOST BUS based
HTH
WopOnTour
 

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