Database Develop

leo headset / headphone manipulation

Hi to everyone,
just to let you know, I have added a section Accessories Modification to Leo Wiki and added a HowTo modify the regular htc headset to in-ear headset... basically a picture HowTo...
see
Leo WIKI Headphone Mod

Very cool... now if I could only find someone to do it for me! Heheh...

derGrafZahl said:
Hi to everyone,
just to let you know, I have added a section Accessories Modification to Leo Wiki and added a HowTo modify the regular htc headset to in-ear headset... basically a picture HowTo...
see
Leo WIKI Headphone Mod
Click to expand...
Click to collapse
very good mate, wanna do mine for me lol......theres no way i can do that.

I just did it a minute ago. I didn't realise my HD2 remote had controls on it as its never been out of the box - so I modified it for my snowboard helmet.
I put a male 3.5mm jack on the end instead of a set of headphones though. Buzzed through the 4 poles on the 3.5mm jack that I was using, and matched them up with the ones inside the remote. I left one of the ground (green) empty as I only needed one ground. Sitting with my helmet on just now listening to music testing it out!!
Thanks for the guide - very simple. I'll get some epoxy at work tomorrow to glue round the edges to make sure the cable doesnt pull out.
My next question is - I have MSVC installed, and the play button activates it. Is there any way to get this remote to control the volume... either normally or through MSVC?
Cheers...

Sounds great! Would like to see a picture if you have one...

derGrafZahl said:
Sounds great! Would like to see a picture if you have one...
Click to expand...
Click to collapse
Its just looks the same - but with a 3.5mm male plug on either end of the remote! I had to label them, as it only works one way round obviously!

Just followed your guide which worked a treat The innards of my remote are slightly different though, no sleeves to hold the wires in place, only this horrible glue/resin which is a real pain to remove. Used some super glue at the end which should hold the wires in place hopefully.
Good guide, thanks. I really hated those HTC earphones!

p3eps said:
I just did it a minute ago. I didn't realise my HD2 remote had controls on it as its never been out of the box - so I modified it for my snowboard helmet.
I put a male 3.5mm jack on the end instead of a set of headphones though. Buzzed through the 4 poles on the 3.5mm jack that I was using, and matched them up with the ones inside the remote. I left one of the ground (green) empty as I only needed one ground. Sitting with my helmet on just now listening to music testing it out!!
Thanks for the guide - very simple. I'll get some epoxy at work tomorrow to glue round the edges to make sure the cable doesnt pull out.
My next question is - I have MSVC installed, and the play button activates it. Is there any way to get this remote to control the volume... either normally or through MSVC?
Cheers...
Click to expand...
Click to collapse
Hi I am not sure I understand (probably just dumb) but I would appreciate it if you could explain or perhaps post pictures?

thank you for doing this write up. followed it and it worked perfectly .
had a bit of trouble soldering a connection peice accross the 2 negative points but apart from that it went very well

I've done a slightly different take on this, I snipped the lead between the control module and the headphones and soldered a inline 3.5mm jack socket. This enables me to plug my Sennheiser HD-25 headphones in without having to damage the lead and in fact plug any standard set of headphones in whilst keeping the full functionality of the remote module...

Starfury said:
I've done a slightly different take on this, I snipped the lead between the control module and the headphones and soldered a inline 3.5mm jack socket. This enables me to plug my Sennheiser HD-25 headphones in without having to damage the lead and in fact plug any standard set of headphones in whilst keeping the full functionality of the remote module...
Click to expand...
Click to collapse
Oh MY GOD I feel sooooo stupid I have had my head in the sand!!
Thanks for a simpler/common sense (less destructive) way
I started the mod on the wiki page and then sat back and thought why don't
I was also looking headphones that have volume control and realised the standard ones don't have volume control.
I will go down to the local store and get some half decent headphones and connect them up.
Just one thing, can you identify the correct wiring to the inline 3.5mm jack socket (pics would be great)

I had it this way on my last sony ericsson cell phone headset. A 3.5mm cable right after the remote button. But the wire was short enough to not make the whole headset cable too long.
A volume control probably can be added like on other headphones. But the leo device won't respond to the volume control, rather a resistor will lower it externaly.
Thanks for contributing all the nice ideas. Keep it up!

Great guide. I used it to blend my crappy Leo headset base to my fab Audio Technica ATH-03 headset - thumping base at last!

It must be me but I am struggling getting this to work well.
I have stripped the cables between the headphones and the remote control unit. This exposes 4 cables - 2 brass, 1 green, 1 red. I intend to wire these two a femail headphone socket so I can just use my own headphones.
The female headphone socket I need to attach these cables to has three terminals only (left, right and centre). I assume the left and right terminals are for red and green. However I have attached these and the sound is tinny. When I push one of the brass coloured cables onto either of the red or green terminal I get bass?
Can someone confirm what the cable connections should be?

The copper colored wire is ground, red and green is left and right channel (don't know which is which, but keep the order). You can solder the two copper wires together but be also shure to get rid of the isolation of each wire or they won't have contact.

derGrafZahl said:
The copper colored wire is ground, red and green is left and right channel (don't know which is which, but keep the order). You can solder the two copper wires together but be also shure to get rid of the isolation of each wire or they won't have contact.
Click to expand...
Click to collapse
GROUNDING !! I thought the cables looked a bit wierd when I took off the outer black cover. Now that is why it is tinny and it explains why the connections worked only when I touched the ends of the cables to the 3.5mm jack!!!
However the cables are so fine I am not sure how you would go about stripping any outer layer off. What tool do you use??
Also it appears that the outer coloured layers (red and green) are mixed in with what appears to be strands of what appear to be white fibre??
Note: I have just used tape to temporarily hold the outer female 3.5mm casing steady whilst I solder the connections.
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You can get rid of the isolation by using your solder iron. It basically melts off when it gets hot. But be sure not to free too much wire since you don't want them to connect after you have put everything together. The white fibre wires are a pain ***. Try to cut them of prior to soldering.
*beware: this is rather my noob experience with these headphone wires which I collected over time...* better ask an expert!

Hi,
does someone knows the HD2 headset handsfree pinout?
I want to connect a headset with microphone to the 3,5mm outlet.
I need these pinout to make a adaptor.
The headset I have tried wasn´t able to transmit the speech.
Thanks

Guys,
If you're worried about damaging the in-line controls, then don't access it. You can always do the previously-mentioned method of snipping the line downstream to the remote, and soldering on a 3.5mm port.
If you don't want the added bulk of a port, there's also a third method (which is what I chose to do). Dismantle the actual headphones themselves -- the driver is held to the casing only by a thin elastic band. Once in, you'll see the 2 leads soldered onto the driver. Remove them, untie the stopper knot.
Repeat this with the headphones of your choice, then transplant those onto the line.
This way, you're basically moving the cans onto the factory line, without losing length and putting the remote at risk.
Now all I need to do is find a software solution to use the in-line controls to control GSPlayer....

Here is an image of my HTC inline remote with female 3.5mm jack attached.
And here is an image of my bandaged hand from picking up the wrong end of the soldering iron.
It actually wasn't too much of a difficult job, haven't done any soldering in a while and other than a couple of burns to my fingers it all went swimmingly.
God knows why they dont sell these things separately, defies belief.
Oh and to anyone living in the UK or anywhere else for that matter, I would happily do this job for you if you aren't handy with a soldering iron. Got alot from this forum so its only right to give something back. Obviously you would need to supply the female jack and I would offer no guarantees I'm not going to break you in-line remote but I would do my best . PM me if ya interested.

[Q] Right angle connector for headphones?

Well the bundled stock headphones include a right angle connector.
But I want to use my iPhone headphones (aftermarket, not the bundled ones)
There's plenty of right angle connectors that are 3 conductor/2 band but you lose the mic/play button with that.
Has anyone found a right angle adaptor with 4 condutor/3 bands?
Without a right angle adapter I fear too much movement will damage the port or the connector on the headphones (and it doesnt really feel right in the pocket)

Found this one, It may be cheaper to build your own.
I also found some that include are TRRS at the phone (male) end, TRS at the female end and include a mic like this one. With this adapter you can use any headphones and still make calls.

The first like seems to be what I need, it's a bit pricier then what I wanted but it's the right description of what I want. If there was one for approx $10 inc shipping it'd be perfect.
My headphones are the apple in ear headphones so they already include a mic (and more importantly a button to control audio)

marvin02 said:
Found this one, It may be cheaper to build your own.
Click to expand...
Click to collapse
That's perfect, but the pricing is loonacy !

It came to nearly $20 after (even the cheapest) shipping. As the headphone jack was the last piece from keeping me from completely retiring my old iphone (i only used it for music) I figured it while it was expensive it was redicilously expensive.
Once it arrives i'll do a mini review of it, should be here by the middle of the week.

You could probably get the right angle plug and make one, but then you have to actually take the time to make the darn thing. you would also need the straight plug and wire and solder and the skill, Nah - I would probably order one just like you did.

Mini-review
So I recieved my connector today.
It doesnt match the picture exactly on the earlier link, but that's a good thing.
The headphone port body seems to be made of electrical shrinkwrap. This good as it means there's nothing on it that can possibly scratch your phone. The issue is that the overall look makes it look like someone hand assembeled it and is not factory made.
It does exactly what it's supposed to do, passes all signals without any perceptable loss in quality.
Pros:
TRRS on both ends (passes all 4 wires)
No metal on body so cant scratch anything
No perceptable change in audio quality
Cons:
Electrical shrinkwrap doesnt scream quality
Price, very expensive for what it is and the build quality
Other:
Doesnt match picture
Cable is 6 inches
Cable is very thick! compare the headphone cable and the extension's cable.
Final Thoughts:
If it were around $8-15 with shipping it'd be a pretty good buy even for it's quality. At $20 it's a bit much for something so small even if it had really good build quality/materials.
But as I mentioned earlier this is the last piece I needed to make my streak fully replace my old iphone. Being able to carry 1 less device makes the high cost not so high.
Issues left to tackle related to streak:
I'm currently using doubletwist to sync with my itunes library and as my music player, currently you can only do single press on the headphone button to play/stop music. It cant do double press to skip forward a track or triple press to go back a track.
Edit: It turns out doubletwist does support double press to skip a track, but not triple press to return to a track. It's a bit finicky though, as it seems to be a hack on detecting that you pressed play/stop quickly and not as a single smooth command.
Also unfortunately you cant use the vol up/vol down button on the headphones (but this isnt the fault of the streak, it's intentional vendor lock-in)
As I'm currently using the apple in-ear headphones I dont expect to change them any time soon, not that other non iphone headphones support volume buttons on the mic block anyway.
The volume buttons on the streak are small and with the right angle connector connected and the port so close to the vol buttons it might be a bit difficult to change the volume without removing it from your pocket. As I have no case for my streak but did for my iphone I dont have the case to guide me to the buttons as easily (You can feel the vol buttons even though the outside of jeans with a case) But I have to walk around a bit and try this part first. The vol buttons work fine for me, I have the phone upright in pocket with screen facing outwards. Finding the buttons isnt an issue at all.
The fact the streak has a metal body means I dont need a case to protect the back from scratches (the front is a different story).

Great review, thanks for taking the time to follow up.

Edited review, turns out using the vol buttons is fine even with the connector.
Doubletwist also includes double tap for skip track so it's pretty much everything I need

[Q] audio ... again

Yes, I've read (or skimmed) most, or all, of the threads on this topic.
My NC audio is...
1. too bright, sibilant
2. lacking in bottom end
3. harsh/hissy in the top end
not talking about playback over the built-in speaker. talking about listening with high-end headphones (in my case, some Shure SE315s and also ME Electronics M6).
I'm not talking about the audio jack behaving differently according to how you insert the plug. Not talking about trying to get bluetooth audio. Not talking about Pandora sounding bad, or a lack of an equalizer on the Google Music player, etc.
Has anyone found a solution that will just fix the actual audio quality (as in, tone balance) issues?
edit:
BTW, I did find that using DSPManager (on CM7.1) it gets much better with a custom EQ setting (each band):
+1.0 +0.5 0.0 -0.5 -1.0 -1.5
The top end is still harsh sounding, but at least it's not overbalanced in this case.
This makes me think this is likely a hardware issue... too small or the wrong type of coupling cap somewhere.

Perhaps you guys are not trying to listen to music on your Nook Color, thus the lack of discussion on this thread.
After comparing to my laptop and my HTC phone, I have discovered that at 100 Hz the NC is at least -10dB compared with my phone. This is extreme! I will try to do some FFTs of this over the weekend.
I think it's a hardware problem.
For the time being I have "bass boost" on DSP Manager turned on, along with some rather extreme EQ settings. It still sounds bad, but at least it's not ear-bleedingly bad.

I've noticed this too with other "lower end" devices, or devices where the engineers aren't too overly-concerned with its audio quality. They usually don't sound the best. I'm sure it's not just your imagination on this. And to think I was actually considering getting a nook as a cheap in-car entertainment device... ugh

NRGZ28 said:
I've noticed this too with other "lower end" devices, or devices where the engineers aren't too overly-concerned with its audio quality. They usually don't sound the best. I'm sure it's not just your imagination on this. And to think I was actually considering getting a nook as a cheap in-car entertainment device... ugh
Click to expand...
Click to collapse
I don't think it's because it's "low-end".
I think one of a couple of things may be at play here.
1. the NC is intended to play only through the internal speaker and/or only play audiobooks (spoken word only). So they intentionally rolled off the bottom end (and most of the midrange as well).
2. audio was not even on the minds of the engineers of the NC, so they didn't bother to check what value coupling capacitors or filter components will work correctly
3. the software/driver is programming the audio device with an extreme HPF intentionally
The reason I don't think it's just because it's "cheap" is because a $20 MP3 player will get all of this right. In fact, it's almost trivial to get this more than good enough. The rest of the NC hardware is way more well-done than this. This screen would not be on a "cheap" device where they severely cut corners on audio by oversight.
So my suspicion is that the audio behavior of the NC is quite intentional. I don't know if it's HW or SW. I seriously hope it's SW.
Glancing at the datasheet for the audio chip (http://www.ti.com/lit/ds/slas671/slas671.pdf) I notice that the audio device has automatic headset detection. This does not seem to be implemented on the NC. Maybe that's the problem. It also has two audio inputs. The more I look at this, the more I want to crack open my NC. The datasheet suggests AC coupling the headphone outputs so there is some capacitor likely in series with each of these lines. IMHO this is the most likely culprit to the NC's crappy sound, if it is a hardware problem. In this case it's only two components to swap, should be a snap. But I don't really want to solder on my NC.
The DRC (dynamic range control) does have a HPF that might have the ability to cause this crummy sound in software, but I doubt it. However, it would not surprise me for the NC developers to turn on some DRC all the time.
I guess I really need to get at the source code of whatever the driver is for the audio device, or get a busted NC so I can trace the output circuit and determine if it's a hardware issue.
Or maybe I'll just not use this to listen to music and watch movies.

OK. This is quite strange.
For a quick experiment, I did a FFT on pink noise playback from my Nook Color, my HTC Aria phone, and my computer's sound device (in this case, Tascam US-144).
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Now, of course I am not playing this into HEADPHONES. In fact, the input of my US-144 "Line In" that I used to test this is AC-coupled and about 50K ohms.
Into that impedance, the output of the NC looks pretty freakin' flat. Moreso than my phone, in fact. So this is good news for you guys wanting to use a NC to plug into the Line In on some device. There is nothing wrong with the audio. It looks great.
However, since my ears, with my earphones, told me that the NC's output was anything BUT flat, I decided to do another test. This time I clipped in an 8 ohm load across the output, to see what the NC's frequency response looks like into an 8 ohm load. I did this also for my phone for comparison.
The NC's output is about -25dB at 100Hz going into an 8 ohm load (typical headphones are maybe more like 16 ohms). As you can see, this is hugely different from the 25K load output.
The verdict? The NC's output is very reactive according to what load you attach to it. Plugging in most headphones will result in a huge roll-off of the bottom end. You could plug it into a buffer or external headphone amp and it would probably sound just fine.
And for comparison, I did the same test with my HTC Aria, and the 8 ohm output looks pretty much exactly like the no-load output. The Aria is a teeny bit lower in the sub-100Hz range than the NC into no-load, ant it is pretty much exactly the same into an 8 ohm load.
After making this discovery, I am more inclined to think this is a hardware design problem, with the output coupling caps being too small.
Armed with the frequency response curves, I experimented with DSPManager EQ settings to try and come up with an EQ that gets it close to right into an 8 ohm load. It is impossible to do it.
However, with DPSManager's "bass boost" turned on, and "Moderate", and EQ settings of +10, 0, -10, -10, -10, -10 it gets to "flat" but not "pink". I am guessing it's distortion showing up at the top end.
In all, this kind of sucks.

Thank you for the info. I would look at the coupling capacitors as well. If they're Tantalum I would replace them with Aluminum Oxide and ensure the capacity is at least 220ufd. The problem would be finding the room. In some experiments I did years ago repairing a portable CD player, Tantalum did awful things to high frequency reproduction.
EDIT: here's a picture of the audio circuit on the motherboard (both from ZDnet):
NOOK COLOR
I cannot identify what I would think are the two headphone coupling capacitors. I suspect they are very small value. They *look* like ceramic (color, no polarity markings) and if so, they would be marginally suitable for a line out and sonically and electrically useless for headphones for music listening.
To contrast:
NOOK TABLET:
I am assuming the large two black capacitors side by side are the headphone coupling capacitors. I do believe these to be tantalum electrolytics (color, polarity markings, shape).
S 7 j e
Trying to interpret that code.
My best determination is 47uf @ 16v -- the "j" may be a tolerance code.
If that is the case then 47uf is way too small of a value for any strong bass output at low impedances (16-32ohm). Minimally acceptable at best.
Color and Tablet:
Both circuits seem to have a very small (pf) capacitor after each coupling cap as a high frequency roll off filter. Not unusual for portable equipment if the capacitor value isn't too large causing excessive rolloff.

You sir are a star! So an amplified set of headphones is the key?

Possibly. I still think there would be issues with Nook's coupling capacitor type and value but the input impedance of the headphone amp might overcome the frequency response issue. Sound quality and noise may be another problem that the headphone amp might not address. Tantalums are not good for sound. That is, garbage in, garbage out.
There may be other problems concerning the configuration of the sound chip in the firmware. The TI chip is capable of a lot of sonic "tricks" but based upon your graphs maybe the sound isn't too compromised in the firmware.

Hard to tell if those are the headphone output coupling caps without tracing the circuit or at least being able to see the alignment dot on the component package of the audio chip. However, if those are the headphone output caps, then they are followed by a ferrite bead and parallel caps most likely to trim off HF noise as well, evidenced by just looking at the pic.
The Nook Tablet pic definitely has bigger caps, probably tantalum, and who knows the value but that's not a 7343 package, so it can't be more than maybe 100uF.
Looking at the FFT, it looks like about a 1KHz Fc into my 8 ohm load, so I am guessing the caps in a NC are more like 22uF. 220uF still gives like 90Hz Fc into 8 ohms, down to 45Hz into 16 ohms. To get full bandwidth into 16 ohms is going to require about 470uF. Maybe compromise at 330uF and hope you have bigger impedance cans.
Those look like 1206 packages on the NC and 1812 package on the NT to me. Even a tantalum at 470uF is going to be a whole lot better, if this is in fact like 22uF. However, finding an 1812 cap at 220uF or 470uF may be extremely difficult. I am not going to argue about putting a different material cap in here because it's just way too small. A brief check of Mouser shows 7343 is the smallest 470uF caps even at 2.5V in tantalum. They have 6032s in 330uF. But those are way too big.
How hard is it to get the NC apart to the point at which this picture was taken? Do you have to unsolder any components to get there?
I wonder if there is any DC on those outputs, or whether these caps can just be jumpered.
The datasheet says the headphone outputs are rated to drive a 16 ohm load. I guess I was overloading them a little into 8 ohms.
After scanning caps, I think it's pretty much impossible to find a reasonable value cap that will fit into a 1206 or 1210 SMD space. Even the 1812s on the NT are not nearly big enough size-wise. So the only way to solve this with hardware mods is to either put caps somewhere in the wiring between the jack and the board, and jumper the caps on the board, or just jumper the caps on the board and hope for no DC on the outputs. Looks like a good time to use an external headphone amp, or noise-canceling headphones (have a built-in amp).

BTW, here's the cheapest, easiest solution to this problem:
http://www.amazon.com/Fiio-E3-BK-E3-Headphone-Amp/dp/B001MPWMDA
And if I were to crack open my NC, rather than doing any surgery or trying to cram different caps in there, I would do this: take the whole PCB from an E3 and shoehorn it into the NC in some open space, wire it between the headphone jack and the headphone output on the NC PCB, and pick up some power from the NC somewhere to run the E3.

Have you installed Dalingren's Nook Tweaks from the market? You can adjust audio settings using this app, specifically increase DAC, adlust headphone gain, speaker gain. Warning! Increasing DAC too high will damage your speaker. I have my DAC setting about 5/8 inch from the left under the a and s in the word "increasing".

hwong96 said:
Have you installed Dalingren's Nook Tweaks from the market? You can adjust audio settings using this app, specifically increase DAC, adlust headphone gain, speaker gain. Warning! Increasing DAC too high will damage your speaker. I have my DAC setting about 5/8 inch from the left under the a and s in the word "increasing".
Click to expand...
Click to collapse
Yes, this is not a volume problem. It's a frequency response problem, related to the impedance of the device connected. Please see the plots.

I posted earlier about my solution to this. By no means cost effective or portable. FiiO E7 USB DAC and CM7. I stream and download 320 bit from MOG. Great for me working hours at desk. Download is unlimited and can listen offline. The audio quality with this little rig is superb. As in unbelievable. I also use good headphones.
Sent from my NookColor using Tapatalk

22jjones said:
I posted earlier about my solution to this. By no means cost effective or portable. FiiO E7 USB DAC and CM7.
Click to expand...
Click to collapse
You using this with USB Host Mode? Is it drawing power from the USB?
Certainly this will sound good but like you say, it's hardly portable. Now, if it were bluetooth rather than USB...
I think a FiiO E3 or E5 headphone amp will mostly fix the main problems, while not improving the DAC or noise performance any. It will definitely fix the reactivity of the output stage. Plus an E5 is cheap + rechargeable and an E3 extremely cheap and extremely compact, barely noticeable and perfectly portable.
I plan to use my NC to read, listen to music and watch movies while on long plane rides, which are all too frequent with my job. Long battery life is key (so drawing power on USB host mode may be bad) and noise performance is not critical. For this kind of thing, I think a small external headphone buffer amp is the ideal solution.

No power drawn from USB, the FiiO has it's own rechargeable battery, one charge will last much longer than the Nook. You have to turn charging off on the FiiO while plugged in to Nook. It is using USB host mode. Add Sennheiser CXC 700 ear buds, and the rig is entering into the audiophile zone.
I think you're right, a small headphone amp, and some EQ will be good. I just did my setup as kind of a quest on how far I could go with Nook audio!

mr72 said:
BTW, here's the cheapest, easiest solution to this problem:
http://www.amazon.com/Fiio-E3-BK-E3-Headphone-Amp/dp/B001MPWMDA
And if I were to crack open my NC, rather than doing any surgery or trying to cram different caps in there, I would do this: take the whole PCB from an E3 and shoehorn it into the NC in some open space, wire it between the headphone jack and the headphone output on the NC PCB, and pick up some power from the NC somewhere to run the E3.
Click to expand...
Click to collapse
That E3 also notes it's for 16+ ohm devices. How does that fix it if you are using your 8 ohm headphones?

The two pair of earphones I will be using are 16 ohms and 23 ohms. I tested the NC's audio output into an 8 ohm load simply because that's the practical lower limit for headphones. They are much more commonly 16 ohms or more.
However, to answer your question specifically, it probably doesn't matter, but it's not worth getting into here. The LM4917 amplifier used in the FiiO is rated at 95mW into a 16 ohm minimum load. Running into a smaller load will just limit the maximum voltage swing or increase distortion when the amplifier is running on max.
FWIW, I think I could probably dead-bug a LM4917 into a NC easier than cramming big output coupling caps in there. That'd fix it as well.

Gutted a nook color and perma-installed it in a Smart Car. :)

I've decided to do it! I gutted and installed a nook color in my stereo space. It works great and is way better than the stock radio for way cheaper than a 7" lcd head unit. Let me explain..
I gutted the nook and took measurements for its screen size against the opening of a double-DIN cavity for car stereos and height-wise it is perfect, but width, it falls a bit short. Went with it anyway, resoldered the home key to lead wires to a button on the face plate and covered up the spacing with some black plastic matching the housing. Works great! Power and volume buttons are also relocated. I'll keep the volume buttons as volume buttons until I get an external pre-amp with a volume potentiometer, see below. Once I get that set up, I'll re-map the volume buttons to back and menu for ease of navigation without button savior.
Heres the hiccup I had... I was planning on running the headphone jack output straight to the amp, turns out that was too quiet.. upon gutting the nook I realized that the speaker isnt soldered to the board, and only makes contact by springs. The speaker contact pads? Pre-amped, but outputs both channels through one output as opposed to headphone stereo.. For now, it sits as the pre-amped speaker output to amp and speakers, but I will be looking somewhere for a decent headphone/small preamp to run stereo to all 4 channels of my handy-dandy Sure 4x100w class D mini amp.
It has some serious volume for a 5x5" pcb with a heatsink! Running on a 19v 130w laptop charger off of a 12v inverter, I am able to get pretty good sound out of it. Because the power supply is a bit lacking, its nowhere near max quality/volume. Just loud enough to start to rumble the doors. I'd like to find a 12v to 32v 10a step up but I've not been able to find one.. Tried to wire a 12v to 5v dc step down converter to the nook's battery terminal but it failed to see it. Not sure of the wiring involved in there for detecting battery charge and voltage, but the battery has 5 wires. If anyone knows how I can wire this to run off of a 12v to 5v 1a USB charger, thatd be awesome...
So nook's speaker output -> amp input -> 4 speaker channels, one to each of the 4 speakers that I have in the car. Added two additional speakers in the rear pillar covers, in addition to the stock 2 in the doors. Swapped the stock ones for Polk 6.5" 100w speakers.
I didnt take too many pictures along the way but everything is so exposed you can see how all the wires are ran throughout the setup. I also added a headphone input to the RCA jacks so you can plug in a different player to the front of the unit straight to the amp but again, it wont be pre-amped. Works fine enough as is for phone conversations which is all I really plan on using it for anyway.
Heres pics of what I have as of now. I'll be either stencil spray painting or putting decals on to mark what the buttons do. Future volume potentiometer will go up top right. I'll put on a fancier aux bezel as well to clean that look up a bit.
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What I'm really curious about is if anyone knows an app that lets the nook receive audio from another device, and if I can control that device through the nook, essentially allowing me to run pandora or internet radio on my phone, and have it transmit to the nook. That's probably a far fetched app and very specific but I'd like to know if anyone knows of anything that they use for other purposes that may suit this.
Any input would be awesome. Again, I'm not going for pristine audio quality, just more functionality. It already sounds better than my stock radio and it adds way more functionality than stock as well. If you have any cool app suggestions for in car use, that'd be awesome too. (planning on running torque pro on it too, should be awesome for data logging and whatever else it can do... I'll let you know.)

That looks great! Well done! The separate controls are a very nice touch.
As far as pandora, etc. Why not install the applications on the nook and tether through your phone (maybe you gave an explanation, but I'm bouncing back and forth on look at this and work, mainly came for the pics )
Make sure you get tether GPS! If I ever decide to do something similar, I pay ping you for a write-up on doing this
Again, awesome job!

I already have tether GPS but its nothing without a data connection and I don't pay for tethering so id rather not use it. Same thing with Pandora.
Sent from my DROIDX using XDA App

I don't know if I should be sorry for the Nook or stunned by your work...
Looking at my Nook, how it sits in it's Book Cover, dealing me joy with countless books, Music, Videos, Internet Browsing, etc. every day, I would feel kinda sorry tearing it apart.
However... I've got a feeling the Nook feels at home where you put him.

mhornfeck72205 said:
I already have tether GPS but its nothing without a data connection and I don't pay for tethering so id rather not use it. Same thing with Pandora.
Sent from my DROIDX using XDA App
Click to expand...
Click to collapse
So why not root your phone and use a tethering app?
Google has their own wifi tether app (other than AOSP, which is usually ripped out or blocked).
http://code.google.com/p/android-wifi-tether/
There are also quite a few others on the market.

Nice work. Geez, the NC is the new car PC, between this and the Jeep guy (both beautiful jobs though)

Very impressive work! I'm blown away -- you did a great job.

I guess you voided your warranty by now.

How are you powering the Nook? through the proprietary cable?
I am puzzled about your 12 volt to 5v statement, and would think it would be ok to wire a usb connector to a 5V 2A+ regulator. (USB jack has to be configured for high power out spec like nook charger).

Thanks everyone!
I'm powering the nook from the nook wall charger also plugged into the 12v inverter straight to the charging usb port with the stock cable. I'd love to be able to have something wired straight to the battery terminals on the board so it would be a key-on-nook-on kind of setup or maybe switched so I dont have to leave the key in to listen to music.. That way I dont have to worry about keeping the battery charged up(it draws more than the charger puts out with the screen always on, so it slowly goes down)

biohazrd51 said:
So why not root your phone and use a tethering app?
Google has their own wifi tether app (other than AOSP, which is usually ripped out or blocked).
http://code.google.com/p/android-wifi-tether/
There are also quite a few others on the market.
Click to expand...
Click to collapse
Phone is already rooted, customized in every way possible, and running Liberty rom. I have a droid x and last I heard when p3droid removed the tether patch from tbh app, they were either sending out texts to people found to be tethering, charging them for the monthly rate, or charging them for all of the data they've used.Id rather not end up having Verizon charge me for the tethering if they actually are doing that.

Why not get a bluetooth-to-audio adapter and put the receiver right next to the transmitter chip? Works great but short range which is no problem in a permanent install.
It would also give you a line level output and you wouldn't have to deal with the high pass filtering that nukes your low shelf.
I am not familiar with a bluetooth-to-line adapter, but, they must exist and can't cost more than $100....
Sent from my SPH-D710 using XDA App

Looking to cut corners and just use the bluetooth that's built into both devices already. Last resort is buying extras..

mhornfeck72205 said:
Phone is already rooted, customized in every way possible, and running Liberty rom. I have a droid x and last I heard when p3droid removed the tether patch from tbh app, they were either sending out texts to people found to be tethering, charging them for the monthly rate, or charging them for all of the data they've used.Id rather not end up having Verizon charge me for the tethering if they actually are doing that.
Click to expand...
Click to collapse
I understand. I remember hearing about that, but thought it was iPhone users only. I get messages from tmobile only when I tether with my laptop, but changing the browser user agent gets around it (they also don't automatically add the charge like verizon and at&t). I think that is carrier's primary means of detection. I stream pandora in the car to my old iphone (I still have the dock) using tether on my phone and never had one issue.
An alternative would be great for you, but I don't see too many problems. Besides, if they tack it on, it'd only be $20 or so for a month then you can remove it from your plan.

tried to do it anyway with the link posted above for the google wireless tether and it still always brings me to the https://dunsp.vzw.com/newSelfProvisioning/SelfProvisioning website.
:-(

Heres a picture of my car running the torque pro app.
Its pretty sweet when the car tells you "Engine at operating temperature" and "Icy Conditions possible" and even more. There are countless gauges and graphs and widgets you can track with this app, only in the pro version. It is easily worth the $18+$5 for the dongle and app... amazing...

Only thing is you have ended up with mono sound and not stereo
no way!

Best Stereo Bluetooth headset and speaker for hang-out moments

Like to share with all my current IEM, Stereo Bluetooth headset, Portable Stereo Bluetooth Speaker, and Flip cover case for self hang-out or gathering moments. All of them has been tested and working very well with my Galaxy Note II N7105 LTE. Their selection are out of many choosen and tested stereo bluetooth headset and speaker, IEM and case gadgets. Below are the my crowned victory combination.
1. Samsung HS-3000 Stereo Bluetooth used with TDK BA200 IEM.
2. Leadsound i6BT Stereo Bluetooth Speakers.
3. White flip cover soft leather case (soft PVC?) with dual mode stand.
I must says, the above combination are absolutely my All-Time Best gadgets for hangout moments, and does not burned a big hole on you pocket.
In self silent mode, The music from HS3000 + BA200 are absolutely fantastic with sweet details, proper bass sound and very good sound staging. The SQ from HS3000 to BA200 sounded so original when compare plugging BA200 directly into my Galaxy Note 2 LTE. All genres of music play absolutely marvellous. Be it Four Play, Earl Klugh, Marcus Miller, Eric Bibb, Stanley Clarke, Peter White, Chuck Mangione, Miles Davis, The Crusaders, Al Di Meola, Billie Hollidays, Diana Krall, Rebecca Pidgeon, Karen Knowles, Laura Fygi, Sara K, David Craig, Bee Gees, The Police, Eric Clapton, Jay-Z, Pitbull, David Guetta, Maroon5, Nicki Minaj, Carly Rae Jepsen, Taylor Swift, Lana Del Rey, P!nk, Super Junior, TVXQ, BigBang, SHINee, Girls Generation, f(X), PSY, Se7en, BoA, and right up to Rock Heaven of Pink Floyd, Led Zeppelin, The Eagles, The Beatles, Scorpions, Queen, U2, ACDC, Bon Jovi, KISS, Guns N'Roses, Aerosmith, Metallica and so on. God.. there's too many to be mention of my collections. And please don't shoot me if I did not mention your favorites, they are and should be just my favorites as well.
On the other hand let's talk about just Samsung HS3000 Stereo Bluetooth performance alone.
It came with Bluetooth 3.0 (without HS) connectivity which promises better power management between idling/suspend and data transfer mode thus has longer and more stability connection than the older Bluetooth 1.0/1.1, 20/2.1. During my usage over the last 4 weeks, it proven to be the best and the most stable connection. Once connected to my cellphone, it stayed connected for the next 2~3days after many calls, music streaming until it finally power off due to battery run-out. My experiences with my old Moto S705, i.Tech MC803, SE MW600 was not so good as all of them suffered many dis-connection from the cellphone in 1 day. This is excellent result to me. I have never experienced such a long timing connection between my devices and any bluetooth headset in the past 12 years of using bluetooth headset.
On the design side, the pearl white/pink colors HS3000 I'm having look gorgeous with it clean layout.
On the buttons control and layout side,
The front facial, the big square button on front facial for call/end call function was perfectly size and well located for fast response to calls. Not only that, it also work marvellously with single press activating the last call, where long press call up the great Samsung S Voice on my Galaxy Note 2 LTE.
To the left sides, there are 4 buttons for Power, Volume up/down and Sound Alive mode. I am particularly liking the sliding type on/off power button. It provide the most straight forward on/off condition that does not require to long press-and-hold waiting time, and maybe still wondering "did i press correctly and was the bluetooth headset already on or not?" Further impression with the sweetly sounded Voice Prompt Assistant "Ms. Samsung" making the various activities announcement clearly and gently also make me feel good about this HS3000. However, for the volume up/down and sound alive mode buttons usage experience does not hold the same good satisfaction, when compare to call and power buttons. The 3 of them are so close together making them not too ideal for frequent operation and need sometime to get use with. This probably due to compact size of HS3000, the Sound Alive mode button are located close to the volume up button, making it easily pressed by mistake.
To the right side, there are 3 buttons for Play (center), Back track/Rewind (left) and Next track/Fast forward (right). Those 3 buttons work wonderfully controlling my Galaxy Note 2 default Music Player for all the intended functions.
To the back, the big clipper for clipping HS3000 unit provding very firm grip onto any clothing one are wearing. It was a better clipper compare to SE MW600 flimsy clipper that easily dropped off from any clothing that MW600 clipped onto. Moto S705 also having similar good clip power, only it was more bulkier and much heavier than the compact and lightness of the Samsung HS3000 by comparison. Well that's about all I'm gonna say for Samsung HS3000. Next...
In open mode, blasting the i6BT stereo speaker when walking or a Starbuck, Subway, BigM is amazing experience, it make me feel so alive listening to my music, movie, MV and live concerts video's. The SQ of this very portable SBTspeaker sound clear, details and yet with powerful low mid bass. Especially truth when hold it in your hand, the powerful bass will keep thumping on your palm and make me feel so alive and feel like keep playing through it and enjoying all the smiling faces or some of the strange look from surrounding people (igonored them if the way they look at you does not please you).
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how much did it cost you (the set) looks interesting and thanks for sharing your experience !

The set price as below,
1. Galaxy Note 2 LTE N7105 = US$234 (under Singapore Singtel telco 2 years contract)
2. HS3000 = US$59
3. TDK BA200 = US$188, I've got it for US$130 under special price by friend shop.
4. i6BT = US$57
5. Flip case with stand mode = US$12.50

Thanks! Well i do have one item from this list, just the note 2, got it here in Algeria for about 875$ factory unlocked
Sent from my GT-N7100

Totally agree with the HS-3000 - best Apt-X bluetooth receiver out there and so versatile with the ability to connect different headphones/IEMs for different use-case scenarios or 3.5-3.5mm cable for connecting to speakers without bluetooth facilities. Fairly inexpensive to boot (got mine for about $30USD from memory).

NZtechfreak said:
Totally agree with the HS-3000 - best Apt-X bluetooth receiver out there and so versatile with the ability to connect different headphones/IEMs for different use-case scenarios or 3.5-3.5mm cable for connecting to speakers without bluetooth facilities. Fairly inexpensive to boot (got mine for about $30USD from memory).
Click to expand...
Click to collapse
Wow! Yours cost only half of mine price.
Mine was original Samsung set with full box and 1 year warranty as shown on my pciture. What abt yours?
I've learned there's some claimed to be Samsung HS3000, but they are infact OEM set assembled with Samsung chipset board inside, or it was a replica HS3000 only. I've knew this as some of them who offering me that price told me so.

I've just forgotten about the TDK BA200 IEM price.
TDK BA200 was actually price at US$188, but I was lucky to got it for US$130 under special price by friend shop.

12/29 - Added more comments about Samsung HS3000 Stereo Bluetooth headset on connection, design and buttons usage experience.