That came out very nice
Sent from my Galaxy Nexus using Tapatalk 2
That came out very nice
Sent from my Galaxy Nexus using Tapatalk 2
I had a question about DAC's and Signal Processing, so I thought I would explain what I am trying to do with the audio side of my setup, and why the signal processor is so important in the system I choose:
The ODAC is a USB D to A converter board, similar to a USB Sound Card, but it only has Line Out. What it does is take your music while it is in the digital domain and convert it into the cleanest, most accurate, analog line out signal you can get on a PC. It's output quality has been measured and compared to audiophile DAC's costing $1600. The Line Out is 2 volts RMS.
You only need 1 of these DAC's for a sound system.
The fader, is controlled by the JBL MS-8 DSP Sound Processor. It does all the real work, and does many things.
1) First it sums inputs to 2 channels. That means it invalidates any head unit unputs like 5.1, fader controls, tone, volume, etc. It takes all signals you give it, and sums all the lefts, all the rights, and converts to a pure Left and Right input.
2) Next you configure the outputs, up to 8 of them. It can make a 7.1 soundstage by selecting FL, Center, FR, Side L and R, Rear L and R, and Sub. This mode is called Logic7, and sounds just like a THX 7.1 system. I don't have a center speaker, so I configured mine as Front L and R, Rear L and R, Sub L and R, but leave Logic7 mode enabled. Now my Left Right Front Rear fader control gets programmed onto the included remote LCD screen and wireless remote. So is Volume, Tone, and a 31 channel EQ.
3) The next step is I wear these stereo headset microphones that look like walkman headphones, and go through the tuning and time alignment sequence. What it does is send a full range audio sweep through each speaker, and through the headset microphones, measures frequency response received, and how long from when it sent the sweeps, till it measured them. It measures all speakers, compares what it sent with what it measured, and automatically sets the MS-8 to give you perfect frequency response, and time aligned sound. You must repeat this process for Driver seat, Passenger seat, and the 2 back seats if desired. I only did the 2 front seats so I can select best sound for just me, or for both front seats.
Here is the importance of time aligned sound:
Look at this graph:
Graph D is a capture of a drum sequence in a song, about 1.5 milliseconds worth, as seen by Audacity.
Suppose it was a monophonic recording, and both Left and Right had the same notes, then looking at the output of 1 speaker, the sound would look like Graph A.
Now you have 4 channels in your car stereo, so you Play 4 times the same signal like Graph C, because it takes more time for the sound from the furthest speaker to reach your ears, yet you are already hearing the nearest speaker. So what you hear non time aligned sounds like Graph B, and a time aligned signal sounds like Graph A.
You hear music that is not blurry, but super clear, allowing you to hear stuff in your music you never knew was there. We are so used to hearing blurry, noisy, music that when you hear time aligned, low noise, full range music for the first time, it really blows you away. My car stereo sound so much better than my home system, simply because of time alignment.
No you can do all this signal processing with the car pc using software, and get the same results, it's just that I am lazy, so tend to assemble a bunch of off the shelf solutions that require minimal fiddling to achieve the same outcome.
I've been and empty nest-er for 10 years, and work lots of overtime and weekends, so have the funds for the projects, but little time to do them.
The past week I took the carputer out, and installed a second connection to the Joycon Steering Wheel controller, and ran SATA cables outside of the box for an external SSD. I installed a 256GB SSD, and named the drive "Media", and ran the Joycon cable under the center console for now.
I had also had a problem where my boot was stalling with an EB code for 30 seconds so I looked for causes, and the best info I could find is to try a firmware update. So, I flashed and crashed the motherboard, then had to re-format a different bootable USB, and reflash to recover. This fixed my EB error. All motherboard settings remained, and now i'm 10 seconds into windows, and 30 seconds till music is playing in Driveline.
The next issue I had was my battery died, and when it did, there was nothing I could do to get the accessory power to shut off. My amps stayed powered up, even with the key removed. A function of the Metra Onstar retention module's latching no doubt, I had to charge the battery 24 hours with a trickle charger till I could start the engine. The next day I started the engine and idled it for 90 minutes, and the alternator voltage is still at 15.3v. Going to monitor this situation for a while now. Today it was 15.2v the whole drive to work.
I have a box load of parts still waiting to be attached to this project, so it is far from completed.
Awesome build! Finally got through the entire thread. I like your methods and cnc work, very nice. Sounds like you cooked the battery, 15v+ is pretty high, like the batt doesn't want to take a charge. I've cooked my fair share of lead acid batteries over the years and it usually only takes one good deep discharge to really destroy the capacity. Try doing an amp draw test, I was astonished that even with my entire system off my amp draw was still unacceptably high. I settled on putting in a main power switch that ground trips a relay to break or connect my main power feed I ran from the battery. This feeds the PC, hd tuner, Sirius tuner, factory interface and the OBD2 connector. I find power cycling all the hardware seems to keep it very stable, as opposed to having it in "standby" state all the time with the caps juiced up. Some may see it as an inconvenience, but whatever, sometime my truck sits for a week at a time without starting so I like knowing everything is 100% disconnected. When I'm done using the truck for the day I flip it all off. In the morning I flip it back on. Since I did this I stopped buying new batteries :-)
I checked this morning and I am charging at 14.9v , and yesterday after work was charging at 15.3v, so I suspect something is not right. I have never had a good system like this, and never cooked a battery before so don't know what to expect.
My battery has not died again yet, but I have not ran the system without the engine running since it first died.
Sent from my SCH-I535 using Tapatalk 2
In California, its likely harder to tell that the battery capacity is diminished due to the weather. In Michigan it is very apparent on the first cold day, because the truck is just dead. I ended up upgrading my battery anyway from a 750cca to a 880cca monster :-) In my experiences only deep cycle batteries are ok after a deep discharge (i've got 4 of them on my boat) but standard "starter" batteries on cars, cannot take a deep discharge without severely effecting the capacity. Love that white Camaro BTW.
Been doing too much overtime the past few months, so no progress till this weekend. The PC has been running fine, and the only issue I have had is when the CPU load is high the USB DAC looses bits and I hear a clicking sound. I have disabled all the background stuff windows 8 does, but I still get clicks sometimes, when windows uses the USB bus heavily. Mo more Atom processors for me, going I3 or I5 next time.
I installed the USB Hub, and the Phodget 1012_2 module. I put the USB hub (6 port) in the center console, and used the lighter socket inside the console to power it, placing a 3A fuse inside. I put the Phidget under the back seat, and ran a +12 and Ground cable soldered on the underside of main cigarette lighter socket, to the back seat where the Phidget Digital IO card is.
I laser cut a plastic housing for the Phidget, so I can mount it with velcro, but the velcro is on order.
Laser cut parts:
Topside of assembled cover, with USB Cable ty-wrapped in place:
Backside where the velcro will go:
I also took apart the JBL MS-8 display, and soldered blue LED's inside so it will light blue instead of white. This will get mounted on the lighted cup holder panel I am working on. I am thinking of adding a USB socket or 2 next weekend.
I made a little more afterwork progress over the week, now that warmer days are here.
First I tested the Phidget install by operating the digital outputs in Driveline:
Then I looked under the back seat where the Phidget 1012_2 is setting (not hard mounted yet), and verified corrisponding output LED's turn on.
The USB hub is just a bit too big to sit flat in my center console, but I need it there, because I have switched 12v power, am wiring in a Griffin Powermate and 2 USB outlets, and it's a central location for all cable lengths.
There's still enough room to store my bluetooth trackball keyboard, and the remote for my MS-8 processor:
So I laser cut an acrylic center console panel that has 2 USB ports, the Griffin Powermate volume control knob, the JBL MS-8 display that I modified with blue LED backlighting, and holes to store 2 resistive screen stylus pens. I also put blue LED edge lighting so the 1 remaining cupwell is illuminated and the holes around the stylus wells and USB ports illuminate nicely. It's just a simple drop in fit, and although I did drill a hole in the cupwell for the cables, it's easily reversable damage for me as the laser cutter can make a perfect fit plug if I need to remove it:
Here is the new overall console shot showing my command center and theme:
This car is my toy, and a daily driver, so I want it to be fun. I let my inner kid flow with it:
Next steps are adding the footwell lighting, as this project continues. We are never really done... are we?
I modified the skin layout and made new icons for Driveline last month, but had forgotten to post samples, so here is what the skin looks like now:
Looking great! I will try to make some changes to the global skin variables so the transparency effect will apply to the buttons on the Playlist screen (and other screens).