The HiFi chat, build and modification thread!

[apache]

Doug doesn't appear to be one who's swayed by oxygen free copper and imagined diode effects does he?

 

[apache]

Workshop's looking far too tidy...

 

[apache]

Tone Control under way

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.

 

[apache]

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!

Flat

LF Max

LF Min

HF Max

HF Min

 

[greenstiles]

i wait with baited ears.......

 

[greenstiles]

would it be easier to make it battery powered ?

 

[apache]

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!

 

[greenstiles]

I don't understand everything you say......but i'm excited all the same

 

[greenstiles]

here my rotel rcd 855 i think the blue thing out of focus is the clock ??? it says mirophonic all over it....

 

[apache]

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.