Hi my name is Martin Brennan. I designed the Brennan JB7 and I’m working on a new product that contains a Raspberry Pi and will be available to Pi owners in kit form. I’ve release a few details on my website www.brennan.co.uk and would welcome any ideas, suggestions, help from you and your readers. Martin
Welcome to our forum! For a prototype, your project already looks quite polished. 
Does this device use the Raspberry Pi as the audio renderer?
Hi ning-yu
Thanks - B2 uses a Burr Brown / TI PCM2902C Codec with a low noise regulator - basically the TI reference design.
Does that answer your question?
Martin
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