The HiFi chat, build and modification thread!

Doug doesn't appear to be one who's swayed by oxygen free copper and imagined diode effects does he? :LOL:
 
Workshop's looking far too tidy...

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Tone Control under way

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Just waiting for CPC to get their fingers out and send me the pots and capacitors for break frequencies, oh, and come up with a power supply design.
 
Initial measurements on the prototype tone control if anyone's interested. There is a small amount of HF instability (expected with this type of tone control) I can cure that but I don't have any low pF capacitors at home. Will have to grab a few in work tomorrow. Might shift the LF a bit lower, and the HF a bit higher, but will listen first. The HF roll-off is a 'feature' of the crappy soundcard in my measurement PC, and NOT the tone control circuit!

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Flat

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LF Max

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LF Min

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HF Max

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HF Min
 
More difficult to make it battery powered. This needs split power rails, but fret ye not, I have a fairly radical plan :)

Brought home some low value caps to nail the HF stability issue so will do that this weekend. Also thinking about using fet input op-amps so I can dump the dc blocking caps (lower input offset voltage traded off against probably unnecessarily low noise)

Watch this space - It's gonna be good!
 
here my rotel rcd 855 i think the blue thing out of focus is the clock ??? it says mirophonic all over it....




 
The clock (the one you're interested in) is near the DAC (the TDA1541 - which is a very well respected DAC by the way)

The silver can south of the DAC on the second to last pic is the clock crystal.
 
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