What's the priciest part? The SHARC or the mil spec DACs?
The DACs for sure. You can find component parts prices for various quantities at DigiKey, which most small companies (and even some big ones) buy their parts from.
Based on the pictures of the GMB on the Schiit site, the DSP is the Analog Devices ADSP-21478KSWA-1A, which sells for around around $9.50 to $11 per chip depending on how much they order. I would guess that they use the same DSP on both Yggy and GMB. I'll just say $10 since that's easy to add.
The AD5781BRUZ used in GMB is $32 per chip in quantities of 1000. So just the DSP and 4 DACs for a GMB is around $138. That doesn't count the cost of the PC board, the various support chips (power supplies, buffers), or the passives (caps, resistors) or connectors or the assembly cost. I don't know if Schiit does this, but a 2x selling price to build cost structure is not unreasonable depending on your business. For a $400 upgrade, a $200 build cost is in the right ballpark.
The 5791 used in Yggy is far, far, far more expensive at $82/chip in quantity 1000. That's enough for 250 Yggys since it takes 4 DACs. In an earlier
post, Mike said that's the size of their last production run. So that's around $338 per Yggy for 4 DACs and 1 DSP. Add in the PCB and all the other components along with build costs, and it might be almost $500 just to build the DSP and DAC boards: remember they're two different boards in Yggy. More different boards in a modular architecture are usually more expensive to build, all else being equal.
Note the economics of this: Schiit needs to put up $82000 just for the DACs for 250 Yggys, and that's assuming the production has a 100% yield, which it never does. It's good to have a reliable cash flow for your business just so you can actually build stuff to sell. Think about how long the production of an Yggy takes, and that's basically Schiit fronting probably many $100k to get something they can sell hopefully soon.
I'd love to hear about the business side of things, like cash flow, for Schiit. I don't know if Jason can talk meaningfully about it without giving away too many secrets, or if it'd be too boring for everyone. Mismanaging this kind of thing has doomed otherwise wonderful companies.
Reference pricing links:
http://www.digikey.com/product-detail/en/AD5781BRUZ-REEL7/AD5781BRUZ-REEL7TR-ND/2432868
http://www.digikey.com/product-detail/en/AD5791BRUZ/AD5791BRUZ-ND/2606881
http://www.digikey.com/product-detail/en/ADSP-21478KSWZ-1A/ADSP-21478KSWZ-1A-ND/2700216