Upgraded Single Board PCM1794 NOS DDDAC

[vedior]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1)
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered


Total: 9

 

[crazyfrog]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1)
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered


Total: 10 + 6 VHCs

 

[juancho]

Originally Posted by vedior View Post
emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered


Total: 10 + 6 VHCs

 

[ed linssen]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)

Total: 11 + 6 VHCs

 

[ed linssen]

emyeuoi (x1)
PET-240 x2 + 2 set JFETS + 2 set Susumu
Myint67x 3, + 3set JFEct + 3set SuSumu(request for pre solder if available)
Juancho x2 + 2 sets JFETS + 2 sets Susumu
Sterlingmck x2 + 2 set JFETS + 2 set Susumu
BDL x1 + 1 set JFETS + 1 set Susumu
mbcoffman x1 + 1 set JFETS + 1 set Susumu
carlsor x1
naimster x2
kurand x1 + 1 set JFETS + 1 set Susumu
brettlb x1
SimonJ x1 + 1 set JFETS + 1 set Susumu
JanGr. x1 + 1 set JFETS + 1 set Susumu
ed linssen x1 + 1set JFETS + 1 set Susumu
tuyen x1 + 1 set JFETS + 1 set susumu
mr_whocares x2 + 2 set jfets + 2 set susumu
dwjames x1 + 1 set jfets + 1 set susumu
Sovereign x2 + 2 sets JFETS + 2 sets Susumu
titus2002 x1 + 1 set JFETs + 1 set Susumu
rickmcinnis x1 + 1 set JFETS + 1 set Sumumu
pdb x1 + 1 set JFETS + 1 set Susumu
odem81 x1 + 1 set JFETS + 1 set Susumu

PCB= 30
Parts= 25

 

[nige2000]

Wow this thread really grew legs
really glad the ccs and half clock cycle mod seems to be preforming well
great job on the GB boards they look the business
just curious to why your going with the "o" jet using a higher resistor value instead of "r"
the jfets aren't too expensive you could buy several and match them as to use a low r value susumu resistor per ccs

 

[tods]

emyeuoi (x1)
PET-240 x2 + 2 set JFETS + 2 set Susumu
Myint67x 3, + 3set JFEct + 3set SuSumu(request for pre solder if available)
Juancho x2 + 2 sets JFETS + 2 sets Susumu
Sterlingmck x2 + 2 set JFETS + 2 set Susumu
BDL x1 + 1 set JFETS + 1 set Susumu
mbcoffman x1 + 1 set JFETS + 1 set Susumu
carlsor x1
naimster x2
kurand x1 + 1 set JFETS + 1 set Susumu
brettlb x1
SimonJ x1 + 1 set JFETS + 1 set Susumu
JanGr. x1 + 1 set JFETS + 1 set Susumu
ed linssen x1 + 1set JFETS + 1 set Susumu
tuyen x1 + 1 set JFETS + 1 set susumu
mr_whocares x2 + 2 set jfets + 2 set susumu
dwjames x1 + 1 set jfets + 1 set susumu
Sovereign x2 + 2 sets JFETS + 2 sets Susumu
titus2002 x1 + 1 set JFETs + 1 set Susumu
rickmcinnis x1 + 1 set JFETS + 1 set Sumumu
pdb x1 + 1 set JFETS + 1 set Susumu
odem81 x1 + 1 set JFETS + 1 set Susumu
tods x2 + 2 set jfets + 2 set susumu

PCB= 32
Parts= 27

 

[carlsor]

2SK208 "O" versus "R"

Nige2000,

It would be my luck to buy 250 2SK208 "R" JFETS only to find that they are all at the low end of the "R" Idss spec range with an Idss below 0.40ma.

Everyone is free to buy and try the "R" version themselves instead of buying tested "O" JFETS from me. The difference in sound between the 2SK208 "O" and the 6K resistor is huge. The sq difference between the "O" and "R" would be much smaller if there is any perceivable difference at all.

Also, the "O" appears to be the minimum tempco product in the 2SK208 lineup at 0.40ma with the current changing no more than 1% over a temperature range of 25C to 60C.

Instead of wondering why this JFET CCS circuit sounds better than a 6K resistor I've concluded that this CCS device is actually making the PCM1794 DAC chip sound better. This is probably why the designer of the PCM1794 provided a pin 20 for external connection.

 

[nige2000]

Nige2000,

It would be my luck to buy 250 2SK208 "R" JFETS only to find that they are all at the low end of the "R" Idss spec range with an Idss below 0.40ma.

Everyone is free to buy and try the "R" version themselves instead of buying tested "O" JFETS from me. The difference in sound between the 2SK208 "O" and the 6K resistor is huge. The sq difference between the "O" and "R" would be much smaller if there is any perceivable difference at all.

Also, the "O" appears to be the minimum tempco product in the 2SK208 lineup at 0.40ma with the current changing no more than 1% over a temperature range of 25C to 60C.

Instead of wondering why this JFET CCS circuit sounds better than a 6K resistor I've concluded that this CCS device is actually making the PCM1794 DAC chip sound better. This is probably why the designer of the PCM1794 provided a pin 20 for external connection.

Could be just blind luck but the first four 208 r jfets I tested had the same idss
That's never happened me before

No doubt pin 20 has a strong influence on sq
I'm sure there's something better than the jfet solution
but I'm out off CCS testing steam
The 2sk208 seems to be a good comprise between speed and low noise

I got my "r"s at RAdionics

 

[thommy]

emyeuoi (x1)
PET-240 x2 + 2 set JFETS + 2 set Susumu
Myint67x 3, + 3set JFEct + 3set SuSumu(request for pre solder if available)
Juancho x2 + 2 sets JFETS + 2 sets Susumu
Sterlingmck x2 + 2 set JFETS + 2 set Susumu
BDL x1 + 1 set JFETS + 1 set Susumu
mbcoffman x1 + 1 set JFETS + 1 set Susumu
carlsor x1
naimster x2
kurand x1 + 1 set JFETS + 1 set Susumu
brettlb x1
SimonJ x1 + 1 set JFETS + 1 set Susumu
JanGr. x1 + 1 set JFETS + 1 set Susumu
ed linssen x1 + 1set JFETS + 1 set Susumu
tuyen x1 + 1 set JFETS + 1 set susumu
mr_whocares x2 + 2 set jfets + 2 set susumu
dwjames x1 + 1 set jfets + 1 set susumu
Sovereign x2 + 2 sets JFETS + 2 sets Susumu
titus2002 x1 + 1 set JFETs + 1 set Susumu
rickmcinnis x1 + 1 set JFETS + 1 set Sumumu
pdb x1 + 1 set JFETS + 1 set Susumu
odem81 x1 + 1 set JFETS + 1 set Susumu
tods x2 + 2 set jfets + 2 set susumu
thommy x2 + 2 set JFETS + 1 set Susumu

PCB= 34
Parts= 29

 

[thommy]

emyeuoi (CCS x 2)
carlsor (CCS x 20)
juancho (CCS x 4)+parts
crazyfrog (CCS x2)
mk57 (CCS x 8) + parts
SimonJ (CCS x 2) + parts
PET-240 CCS x 4 + parts
sterlingmck (CCS x 4) + parts
zz1969 (CCS x 8) + parts
kurand (CCS x 4) + parts
mbcoffman (CCS x 2) + parts
Myint67 (CSSx16) + Parts
tuyen (CCS x 8) + parts
Brumjam (CCS x 4) + parts
mr_whocares (CCS x 2) + parts
tods (CCS x 8) + parts
IanS1 (CCS x 4) + Parts
dwjames (CCS x 2) + parts
titus2002 (CCS x 8) + parts
BDL (CCS x 2) + parts
Sovereign1 (CCSx4) +Parts
rickmcinnis (CCS x 2) + parts
Superberg (CCS x 20) + parts
Naimster(CCS x 16) + parts
pdb (CCS x 4) + parts
ed linssen (CCS x 4) + parts
pz1: (CCS x 8) + parts
thommy: (CCS x 6) + parts

Total CCS = 170
Parts = 146

 

[NicB]

emyeuoi (x1)
PET-240 x2 + 2 set JFETS + 2 set Susumu
Myint67x 3, + 3set JFEct + 3set SuSumu(request for pre solder if available)
Juancho x2 + 2 sets JFETS + 2 sets Susumu
Sterlingmck x2 + 2 set JFETS + 2 set Susumu
BDL x1 + 1 set JFETS + 1 set Susumu
mbcoffman x1 + 1 set JFETS + 1 set Susumu
carlsor x1
naimster x2
kurand x1 + 1 set JFETS + 1 set Susumu
brettlb x1
SimonJ x1 + 1 set JFETS + 1 set Susumu
JanGr. x1 + 1 set JFETS + 1 set Susumu
ed linssen x1 + 1set JFETS + 1 set Susumu
tuyen x1 + 1 set JFETS + 1 set susumu
mr_whocares x2 + 2 set jfets + 2 set susumu
dwjames x1 + 1 set jfets + 1 set susumu
Sovereign x2 + 2 sets JFETS + 2 sets Susumu
titus2002 x1 + 1 set JFETs + 1 set Susumu
rickmcinnis x1 + 1 set JFETS + 1 set Sumumu
pdb x1 + 1 set JFETS + 1 set Susumu
odem81 x1 + 1 set JFETS + 1 set Susumu
tods x2 + 2 set jfets + 2 set susumu
thommy x2 + 2 set JFETS + 1 set Susumu
NicB x1 + 1 set JFETS + 1 set Susumu

PCB= 35
Parts= 30

 

[NicB]

emyeuoi (CCS x 2)
carlsor (CCS x 20)
juancho (CCS x 4)+parts
crazyfrog (CCS x2)
mk57 (CCS x 8) + parts
SimonJ (CCS x 2) + parts
PET-240 CCS x 4 + parts
sterlingmck (CCS x 4) + parts
zz1969 (CCS x 8) + parts
kurand (CCS x 4) + parts
mbcoffman (CCS x 2) + parts
Myint67 (CSSx16) + Parts
tuyen (CCS x 8) + parts
Brumjam (CCS x 4) + parts
mr_whocares (CCS x 2) + parts
tods (CCS x 8) + parts
IanS1 (CCS x 4) + Parts
dwjames (CCS x 2) + parts
titus2002 (CCS x 8) + parts
BDL (CCS x 2) + parts
Sovereign1 (CCSx4) +Parts
rickmcinnis (CCS x 2) + parts
Superberg (CCS x 20) + parts
Naimster(CCS x 16) + parts
pdb (CCS x 4) + parts
ed linssen (CCS x 4) + parts
pz1: (CCS x 8) + parts
thommy: (CCS x 6) + parts
NicB: (CCS x 2) + parts

Total CCS = 172
Parts = 148

 

[NicB]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)
NicB (clock x 1) + VHCs soldered


Total: 12 + 7 VHCs

 

[emyeuoi]

CCS GB - Corrected List

emyeuoi (CCS x 2)
carlsor (CCS x 20)
juancho (CCS x 4)+parts
crazyfrog (CCS x2)
mk57 (CCS x 8) + parts
SimonJ (CCS x 2) + parts
PET-240 CCS x 12 + parts
sterlingmck (CCS x 4) + parts
zz1969 (CCS x 8) + parts
kurand (CCS x 8) + parts
mbcoffman (CCS x 2) + parts
Myint67 (CSSx16) + Parts
tuyen (CCS x 8) + parts
Brumjam (CCS x 4) + parts
mr_whocares (CCS x 2) + parts
tods (CCS x 8) + parts
IanS1 (CCS x 4) + Parts
dwjames (CCS x 2) + parts
titus2002 (CCS x 8) + parts
BDL (CCS x 2) + parts
Sovereign1 (CCSx4) +Parts
rickmcinnis (CCS x 2) + parts
Superberg (CCS x 20) + parts
Naimster(CCS x 16) + parts
pdb (CCS x 4) + parts
ed linssen (CCS x 4) + parts
pz1: (CCS x 8) + parts
odem81 (CCS x 2) + parts
vedior (CCS x 2) + parts
thommy: (CCS x 6) + parts
NicB: (CCS x 2) + parts

Total CCS = 196
Parts = 172

 

[emyeuoi]

CLOCK GB - List Corrected

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)
NicB (clock x 1) + VHCs soldered


Total: 12 + 9 VHCs

 

[dwjames]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)
NicB (clock x 1) + VHCs soldered
Dwjames (clock x 1)


Total: 13 + 9 VHCs

 

[SimonJ]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)
NicB (clock x 1) + VHCs soldered
Dwjames (clock x 1)
SimonJ (clock x 1)

Total: 14 + 9 VHCs

 

[Sovereign1]

emyeuoi (CLOCK x 1)
Superberg (CLOCK x 1)
BDL (CLOCK x 1) + VHCs soldered
Juancho (clock x 1) + VHCs soldered
chevron (CLOCK x 1) + VHCs soldered
pz1 (clock x 1) + VHCs soldered
sterlingmck (clock x 2) + VHCs soldered
vedior (clock x 1) + VHCs soldered
Crazyfrog (clock x 1) + VHCs soldered
ed linssen (CLOCK x 1)
NicB (clock x 1) + VHCs soldered
Dwjames (clock x 1)
SimonJ (clock x 1)
Sovereign1 (clock x1) + VHS soldered

Total: 16+ 10VHCs

 

[chevron]

Default CCS GB - Corrected List

emyeuoi (CCS x 2)
carlsor (CCS x 20)
juancho (CCS x 4)+parts
crazyfrog (CCS x2)
mk57 (CCS x 8) + parts
SimonJ (CCS x 2) + parts
PET-240 CCS x 12 + parts
sterlingmck (CCS x 4) + parts
zz1969 (CCS x 8) + parts
kurand (CCS x 8) + parts
mbcoffman (CCS x 2) + parts
Myint67 (CSSx16) + Parts
tuyen (CCS x 8) + parts
Brumjam (CCS x 4) + parts
mr_whocares (CCS x 2) + parts
tods (CCS x 8) + parts
IanS1 (CCS x 4) + Parts
dwjames (CCS x 2) + parts
titus2002 (CCS x 8) + parts
BDL (CCS x 2) + parts
Sovereign1 (CCSx4) +Parts
rickmcinnis (CCS x 2) + parts
Superberg (CCS x 20) + parts
Naimster(CCS x 16) + parts
pdb (CCS x 4) + parts
ed linssen (CCS x 4) + parts
pz1: (CCS x 8) + parts
odem81 (CCS x 2) + parts
vedior (CCS x 2) + parts
thommy: (CCS x 6) + parts
NicB: (CCS x 2) + parts
chevron: (CCS x 2) + parts

Total CCS = 198
Parts = 174