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adamslim
2007-07-06, 13:04
I have a strange desire to create a one-box 'Complete Wireless Audio Product' (the name might need some work) as follows:
- Get a big box
- Shove in some decent power supplies
- Pull apart the SB3 and slap it in
- Plonk in a Monica DAC from DIY Paradise
- Pop in a Charlize amplifier, same source

This would probably be used in a bedroom system; I have my eye on a pair of Heybrook Sextets on ebay, but we'll see.

Anyway, it struck me that if I'm taking apart the SB3 and adding various power supplies, I should be able to bypass the regulators in the SB3 and connect better PSUs directly to where it is needed. Question is, what power is needed where in the SB3? Am I going to make any difference, or just fry something?

Sound like fun? Any comments or wise words?

Cheers

Adam

JeffW
2007-07-07, 18:23
I had the same desire as well, mostly driven by the need for a compact all-in-one box. (I'm not allowed to have a rack full of equipment in the living room). I used an SB3, a Power One supply for the SB3, and an AMP5 from 41hz.com, but no DAC. The AMP5 uses a TA2022 chip, a higher powered version of the TA2020 in the Charlize. I'm thinking of doing a "gigh-end" version with a DAC and maybe UCD180 modules. Let me know how yours turns out.

adamslim
2007-07-09, 05:48
Thanks for the replies, good advice.

With respect to the SB3 itself, I'd like to have the display on a totally separate power supply from the rest (actually, I'd like to have several really good power supplies - display, wifi, DAC, main board etc all separate). Is there any documentation of what needs what, and where it needs to go? I would be mildly concerned about feeding 12V to something that wants 5V, or doesn't expect power at all!!

Cheers

Adam

Skunk
2007-07-09, 11:45
I would be mildly concerned about feeding 12V to something that wants 5V, or doesn't expect power at all!!


And also, don't reverse any DC polarity if making direct connections to chips, or you may see smoke :-)

I haven't seen any real documentation, but that may be because it's not necessary. You are planning to use an external DAC after all, so the only thing that would need separating is the clock supply. I believe moving the headphone 3.3V supply to the oscillator is semi-documented (I.e. someone said it's possible, but no step by step instructions are posted).

In a one-box cd player, however, it's considered poor form to convert I2S>spdif>I2S, which is basically what you've sketched out. Consider searching John Swenson's posts on tapping the I2S from Sb3, and sending that to the DAC instead. If you can arrange the DAC close enough to the Sb3 you may not need the buffer chips, but you'll have to check it out.

adamslim
2007-07-10, 05:47
And also, don't reverse any DC polarity if making direct connections to chips, or you may see smoke :-)

I haven't seen any real documentation, but that may be because it's not necessary. You are planning to use an external DAC after all, so the only thing that would need separating is the clock supply. I believe moving the headphone 3.3V supply to the oscillator is semi-documented (I.e. someone said it's possible, but no step by step instructions are posted).

In a one-box cd player, however, it's considered poor form to convert I2S>spdif>I2S, which is basically what you've sketched out. Consider searching John Swenson's posts on tapping the I2S from Sb3, and sending that to the DAC instead. If you can arrange the DAC close enough to the Sb3 you may not need the buffer chips, but you'll have to check it out.

Hmm, that is interesting, looks like I need a crash course in digital audio electronics! I have had a quick search for Swenson's posts, which is certainly worth pursuing. Thanks for the hint.

A

04dgmsilv
2007-07-14, 03:36
Don't know if you've ever seen this guy over on diyaudio, but he did the same concept, but using Peter Daniels parts/kits (LM3875 Gainclone and a NOSDAC).

Check it out, click on Audio Projects below:

http://web.mac.com/noteldov

Dan

adamslim
2007-07-15, 05:51
Don't know if you've ever seen this guy over on diyaudio, but he did the same concept, but using Peter Daniels parts/kits (LM3875 Gainclone and a NOSDAC).

Check it out, click on Audio Projects below:

http://web.mac.com/noteldov

Dan

Wow, impressive. I see that he has also got his project on the case supplier's website! Expensive but gorgeous...