not yet, its on the list. marce is a great source of references for this line of thinking, so yes although i've read some Howard Johnson online, havent forked out the coin for those 2, i'm still brushing up on the math needed for some of this stuff, so its a bit slow going.
i've only recently pulled my finger out to start designing my own stuff from scratch after being in sponge mode for the last few years, but i'm pretty happy with how its all coming together. having a background in graphic design/pre-press has helped a lot at the software level. looking at working the beaglebone black into the mix too.
anyway we should probably give these guys their thread back, do shoot me a PM sometime. I wouldnt mind some referrals for local boardhouses for multilayer if you know any that arent too pricey, i'm just grabbing some 4 layer boards at seeed and gold phoenix before going too hardcore.
but without coplanar waveguides, being even more alien here, the thickness (and FS) is a factor for determining the width of the trace needed and waveguides are going to require impedance controlled layout are they not? cheaper to just get a multilayer board in many cases these days. yeah i'm looking 6 layer, not 8, still too pricey unless you have the ability to run it with other company material like you perhaps. depends, maybe by the time i'm done it'll be cheap enough. most of the logic with mine will be off board though with flex PCB interconnects so its not such a big deal.
I wish the ESS came in a BGA package option
Oh definately on the microstrip stuff. I still prefer CPW, as they are much more forgiving of imperfections in the routing and mostly single mode, also board thickness is much less important. However for my board im intending to have a cml transceiver close enough that transmission line effects don't matter and then run differential into my source that will be based on a zynq fpga.
As for BGA, it is not really necessary, or even helpful to go that far. I mean even Hittite uses QFN for most of their stuff. Just makes routing hard.
I am actually most annoyed about the clock being a cmos input, very hard to convert a pure sine wave into a high quality square wave with no internal terminators. I am going to use one of the new LT chips to do this in my design, running the whole design on a 100MHz OCXO. I need a grand total of 16 channels in my system and so i need 8 of the ESS dac chips. Will be designing boards that use two chips each and build 4 of them.
The system should be capable of 64 or more channels though.
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No, the zynq fpga has an embeded arm cortex A9 built in, this thing will play music direct from my network. No PC required, also allows me to clock the CPU so that it's main clock is derived from the audio clock. This whole system is going to be synchronous baby. I will be able to act as a USB audio sink for a PC though, and I will be designing it so I can send HOA directly into it as a 16 channel pipe and decode it on the fpga.
The FPGA fabric can also be used to implement DSP on the audio. Though i will not need much.
The FPGA fabric can also be used to implement DSP on the audio. Though i will not need much.
There is a new version of this board with I2S.
Remove LCD+ES9018 High-end USB DAC CPU Coaxial fiber 192K-24BIT KIT WLX | eBay
Remove LCD+ES9018 High-end USB DAC CPU Coaxial fiber 192K-24BIT KIT WLX | eBay
I asked for that listing to be removed as it claimed the board had I2S
inputs. It does not.
So now i show my ignorance -
CML = Current mode logic ? (is LVDS comparable).
HOA = ?
So are you implementing FIR crossovers onthe board ?
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CML = Current mode logic.
HOA = Higher Order Ambisonics.
thought i suppose you could implement crossovers on the board too, that is not how I will be using it. Good old analog crossovers for me.
Is CML comparable to LVDS ?
Ah yes, Higher Order Ambisonics.
I had one of these systems as a kit from Clive Sinclair in the seventies
Bolted it onto a 60's radiogram
Similar but different. Higher speed. Much higher speed.
I doubt you had a HOA system in the 70s but you probably did have an ambisonics system.
HOA includes the higher order spherical harmonics and so has much greater positional accuracy. The goal is to build a system that can do 3rd order horixzontal plus 2nd order periphony.
I doubt you had a HOA system in the 70s but you probably did have an ambisonics system.
HOA includes the higher order spherical harmonics and so has much greater positional accuracy. The goal is to build a system that can do 3rd order horixzontal plus 2nd order periphony.
Yeah, just kidding.
But it did work, as long as you repaired the class D amps every few days
I like the ethernet approach, looked at the XMOS stuff but no enough bandwith with there implememtation.
Spend the last 3 years working on how best to get multi channel I2S from a PC.
Started with ASUS Xonar card and LVDS.
Tried PCIe expansion.
Just having a look at USB3.
Digital crossover with room correction.
Needs a lot of horsepower for 26 channels at 24/192.
131072 Taps 64bit.
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131072 taps per channel, or 131072 taps total, either way seems totally doable on an external non-PC board. You seem to forget that we have Multiple overlap ffts and 100Mhz hardware at out disposal, also modern fpgas are not small. These things do Realtime ffts on adds that work at 10GSPS for the military.
131072 taps per channel.
I appreciate they have dedicated fft hardware but find it difficult to compare the real world horsepower,verses say, Intel i7.
Are you sure it does not have I2S input?
Looks like it was listed again with same claim:
Remove LCD ES9018 High End USB DAC CPU Coaxial Fiber 192K 24bit Kit WLX | eBay
As far as I can see from the photos, Weiliang removed kubota regulators. There is also only one ADP150 low noise regulator. The control is made through IC2 port