Yep remove those 4 100uF (Cerefine) and those 2 opamps
You will see U210 U214. Remove these and solder a wire from each to the output sockets to bypass the HDAM and the muting.
Also cut out R651 652 653 654 as the HDAM no longer needs the voltage supply. Oh and remove C655 657 656 658.
Brent
You will see U210 U214. Remove these and solder a wire from each to the output sockets to bypass the HDAM and the muting.
Also cut out R651 652 653 654 as the HDAM no longer needs the voltage supply. Oh and remove C655 657 656 658.
Brent
LOL
Hi brent just done all the sound deadening on the chassis while i got the board out, Now the hard part i noticed when you turn the board up side down looks like not all the legs on the opamp are soldered so when i fit the new ones do i solder all of them or just the ones that are done on the origonal ones
Hi brent thanks alot for your help i have done it and its not on fire. Had a few pink floyd albums on and it sounds really well it does not sound digital any more it sounds a lot smoother and easeyer to listen to but for some reason i have to turn the amp up more. and i noticed it sounds slower than before. So what do you recon next upgrade should be
Well done 
It will sound a little quieter (a good thing) as the HDAM is out of the circuit. The slower and smoother sound is mainly due to less distortion.
The 2 big Brown/gold Silmic capacitors near the transformer need replacing, and as you have a 67 it is ideal to replace these with Mundorf HC 25V max diameter of 26mm. If you drill the holes biggeryou can fit the much better 25000uf or 22000uf HC that are 30mm diameter.
There are also 2 more caps after the 2 regs C805 C806. Rubycon ZA 16v 220uF/470uF work well here. These caps supply the opamps.
Also did you short out resistors R613 614 615 616 just above the opamps
Brent
It will sound a little quieter (a good thing) as the HDAM is out of the circuit. The slower and smoother sound is mainly due to less distortion.
The 2 big Brown/gold Silmic capacitors near the transformer need replacing, and as you have a 67 it is ideal to replace these with Mundorf HC 25V max diameter of 26mm. If you drill the holes biggeryou can fit the much better 25000uf or 22000uf HC that are 30mm diameter.
There are also 2 more caps after the 2 regs C805 C806. Rubycon ZA 16v 220uF/470uF work well here. These caps supply the opamps.
Also did you short out resistors R613 614 615 616 just above the opamps
Brent
That's correct, you have disabled the HDAM and its psu supply doing that.
The R613 614 615 616 are the voltage supply resistors to the opamps. Cut these legs but leave enough leg sticking up so that the legs can be bent over and soldered together (on top of the pcb). You get a more dynamic sound doing this.
Brent
The R613 614 615 616 are the voltage supply resistors to the opamps. Cut these legs but leave enough leg sticking up so that the legs can be bent over and soldered together (on top of the pcb). You get a more dynamic sound doing this.
Brent
If you leave the legs long enough then you can bend them over and solder together from the top.
A bigger higher quality caps offers Lower ESR and better ripple current. This helps keep the power rails cleaner + the larger uF helps with bass and over all soud quality. If you are on a budget then the Panasonic FC 25V 4700uF are pretty good in that location.
Brent
A bigger higher quality caps offers Lower ESR and better ripple current. This helps keep the power rails cleaner + the larger uF helps with bass and over all soud quality. If you are on a budget then the Panasonic FC 25V 4700uF are pretty good in that location.
Brent
Hi again since i have changed opamps and caps and HDAM bypass i have played a fair few cds and i think the midrange is not as good as it was before. Though the bottom end is better trebble is a bit ragged do any of you know were i may have gone wrong. I have just got the caps today for the power supply which i will fitt tommorow
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