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BOSC - HiFi Monoblock Class-D GaN Amp

I have a few questions:
1. Are you planning to continue selling modules for DIY?
2. Also, it seems that the amp needs only a +56V, so a simple but regulated SMPS with one output should be enough, right?
3a. Why are the the 4Ohm and 8Ohm models different? Gain, even input impedance and voltage are different.
3b. What would be the downside of using the 8Ohm (optimised?) model wth 4Ohm speakers, and viceversa?
4. The input impedance seems a bit low, so a buffer may be advisable in some circumstances, esp. without active preamp (as in my case). Would a buffer like Neurochrome's Universal Buffer a good complement?

Roberto
1. Yes, the price will go up to $300 per module in mid January
2. Yes, single output 56V regulated supply. That is what I provide with the amps. The one I provide is rated at 250W.
3. Regardless of the load impedance the amplifier can only provide 150Wrms hence the gain of 4 ohm version is 3dB less. This is so output power is the same into 4 and 8 ohm loads with same input voltage. You can use either version with either 4 or 8ohm speakers.
4. In your case buffer is good idea. Make sure buffer has as low an output impedance, I recommend <50ohm.
 
Those infineon fets are so expensive (20euro) why dont you preffer use gan systems fets (5 euro)?
I guess you chosed Half bridge due to expensive bom but full bridge configration has less THD in general.

How do you handle analog to pwm conversation?

There are no infeneon devices on these boards.

PWM is done with opamps and comparator, I cannot provide exact details that is proprietary information.

This amp is full bridge design. Fully balanced input and output.
 
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Joined 2007
Here is a link to the Audio Xpress review of the BOSC amps.
Audio_Xpress_BOSC_Review.pdf - Google Drive

This is absolutely bonkers (in a positive way). Yes, the Purifi has better measurements, but it is also a significantly more complex topology (three nested feedback loops, and one feed forward loop crossing a feedback point). And yet the B̶O̶S̶C̶ STARKRIMSON manages to reach inaudible levels of noise and distortion, KUDOS. Also, it seems to me that B̶O̶S̶C̶ STARKRIMSON modules are available individually as well, so one could still purchase and integrate (do you/would you also sell to integrators?)

Congratulations for having audibly matched the performance of a long time veteran of this industry in a fraction of the time!