Hello. This will be one of the first times I start a thread here, but I figure I've gotten so much insight from diyma, and the internet, that it's about time I give some output as well.
Anyways, here we go.
The point of this project is to have a seemingly simple install in a e39 BMW, with excellent SQ from a navigation head unit.
First, the Navigation unit is a Panasonic CN-HX3000D (I live in Japan). It features a flipout 720p screen, with an HDMI input (w/HDMI audio btw).
The problem is that the unit does not feature RCA outputs, so I am stuck with the 50w x 4 max output from the head unit amp. I didn't want to install a second SQ oriented head unit, and def. wanted the navigation and the 720p display.
So this here is the idea for the project. Take apart the navigation unit, find the final dac section, tap the digital audio I2S lines, feed the lines to a external dac, and then to external amps. It seemed difficult at first, but this is what I have so far.
Head unit (Panasonic CN-HX3000D):
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DAC located inside navigation unit, and I2S(BCK, LRCK, D-IN1(Front R+L) D-IN2(Rear R+L)) lines tapped and fed outside the unit to a Ethernet cable recepticle
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Now that I got the raw digital lines outside the unit, it was time to figure out which dac to use. I ended up using a pair of Twisted Pear's Buffalo III's(Perhaps worlds first?). The buffaloIII uses the Sabre ES9018 DAC, which feature dynamic range of 133db and a THD of -120db. It sounds amazing btw.
Also, I used the Twisted Pear IVYIII's for the output stage.
The problem of course was powering the units. The Buffalo III's include 3 on-board shunt regulators, so I decided to power the units using a adjustable DC-DC converter set for 5.25 volts directly. I'm hoping the shunt units will help eliminate the DC-DC's noise.
The IVYIII output stage requires +/- 15 volts to operate, and need good clean power. I used a adjustable DC-DC converter set for +/-16.8 volts and fed it to a modified twisted pear Placid BP HD with the bridge rectifier circuit removed, so it could work with the DC +/-16.8 volts instead of AC that would usually be fed from transformers.
Power supply board w/ the two DC-DC Converters.
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Placid BP HD, and the two Buffalo DAC and IVYIII's powered successfully off of a 12v DC source.
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Here is the I2S line coming from a STP Ethernet cable from the head-unit going into the Buffalo DAC's
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I am able to get 4 balanced outputs from the two IVYIII units.
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Where to connect the balanced outputs? The Mcintosh MC430 of course!
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I will have the MC430 feeding the front (HAT Clarus C61-2 and rear fill speakers (HAT Imagine I51-2).
The IVYIII also features single ended outputs that can be used at the same time. I have pulled the L+R pair from the Front DAC to a MCC402 that will be powering a pair of Legatia L8V2's (crossed as subwoofers) on the rear deck as IB.
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As for now, the system sounds great. Because the DSP, the Dolby Digital Processor, the ADC, and the Volume control happens before the DAC in the navigation unit, I am able to retain all of the functions on the Navigation, although I am worried about the internal bit rate of the volume control and the DSP system. I have been unsuccessful in finding a data sheet for the TI DSP that is in the head unit.
My next step is to fit the external DAC into a case, and then I should have the unit ready to be installed into the car. I have the L8V2's on the way, and I'm currently negotiating L1 Pro R2's to replace the stock Clarus tweeters.
I also have 2 pairs of balanced cables, and a pair of RCA's coming from Blue Jeans Cable.
Please let me know if you anyone has any input on the project. I apologize for the messy layout of wires. It's only a prototype.
Anyways, I will keep everyone updated in the future.
Anyways, here we go.
The point of this project is to have a seemingly simple install in a e39 BMW, with excellent SQ from a navigation head unit.
First, the Navigation unit is a Panasonic CN-HX3000D (I live in Japan). It features a flipout 720p screen, with an HDMI input (w/HDMI audio btw).
The problem is that the unit does not feature RCA outputs, so I am stuck with the 50w x 4 max output from the head unit amp. I didn't want to install a second SQ oriented head unit, and def. wanted the navigation and the 720p display.
So this here is the idea for the project. Take apart the navigation unit, find the final dac section, tap the digital audio I2S lines, feed the lines to a external dac, and then to external amps. It seemed difficult at first, but this is what I have so far.
Head unit (Panasonic CN-HX3000D):
DAC located inside navigation unit, and I2S(BCK, LRCK, D-IN1(Front R+L) D-IN2(Rear R+L)) lines tapped and fed outside the unit to a Ethernet cable recepticle
Now that I got the raw digital lines outside the unit, it was time to figure out which dac to use. I ended up using a pair of Twisted Pear's Buffalo III's(Perhaps worlds first?). The buffaloIII uses the Sabre ES9018 DAC, which feature dynamic range of 133db and a THD of -120db. It sounds amazing btw.
Also, I used the Twisted Pear IVYIII's for the output stage.
The problem of course was powering the units. The Buffalo III's include 3 on-board shunt regulators, so I decided to power the units using a adjustable DC-DC converter set for 5.25 volts directly. I'm hoping the shunt units will help eliminate the DC-DC's noise.
The IVYIII output stage requires +/- 15 volts to operate, and need good clean power. I used a adjustable DC-DC converter set for +/-16.8 volts and fed it to a modified twisted pear Placid BP HD with the bridge rectifier circuit removed, so it could work with the DC +/-16.8 volts instead of AC that would usually be fed from transformers.
Power supply board w/ the two DC-DC Converters.
Placid BP HD, and the two Buffalo DAC and IVYIII's powered successfully off of a 12v DC source.
Here is the I2S line coming from a STP Ethernet cable from the head-unit going into the Buffalo DAC's
I am able to get 4 balanced outputs from the two IVYIII units.
Where to connect the balanced outputs? The Mcintosh MC430 of course!
I will have the MC430 feeding the front (HAT Clarus C61-2 and rear fill speakers (HAT Imagine I51-2).
The IVYIII also features single ended outputs that can be used at the same time. I have pulled the L+R pair from the Front DAC to a MCC402 that will be powering a pair of Legatia L8V2's (crossed as subwoofers) on the rear deck as IB.
As for now, the system sounds great. Because the DSP, the Dolby Digital Processor, the ADC, and the Volume control happens before the DAC in the navigation unit, I am able to retain all of the functions on the Navigation, although I am worried about the internal bit rate of the volume control and the DSP system. I have been unsuccessful in finding a data sheet for the TI DSP that is in the head unit.
My next step is to fit the external DAC into a case, and then I should have the unit ready to be installed into the car. I have the L8V2's on the way, and I'm currently negotiating L1 Pro R2's to replace the stock Clarus tweeters.
I also have 2 pairs of balanced cables, and a pair of RCA's coming from Blue Jeans Cable.
Please let me know if you anyone has any input on the project. I apologize for the messy layout of wires. It's only a prototype.
Anyways, I will keep everyone updated in the future.
