The old ones have 250 hfe and the new ones are 160 hfe at least the one I just checked anyway
AU-X1
- Thread starter Willy6
- Start date
Do you think I should get rid of the jumper wire and put it like the schematic shows?
This is a common result, and why I recommended (in the Pioneer Forum recently) not to change original transistors unless you have to. However transistors of modern fabrication will be much less likely to fail prematurely, and will extend the life of the unit.
Really hard to say Willy, I have looked hard at the modification and I can't make up my mind if it's original or not, sometimes retro fitted items can look out of place - but may be correct. If it was me I would leave it in place, and try and get an idea of what was intended, by checking the voltage selection plug with a multimeter. The reason I say this is from the look of it, it might work without the pin 4 jumper and set for US mains - but you could be only using one primary - this is bad.
Need our guardian angel Ron, or Kale to chime in on this one...
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Ronito6
Super Member
Great! New territory at last! Lots to figure out here, but that's the fun part.
Kale has actual experience with that part and it's function,
and so really would have the last word on this issue...but...I vote leave it.
I vote leave it because, if you have to actually undo that jumper,
you can just cut it off later easily.
Easier still if the selector is mounted on the outside of the chassis.
( In which case...Undo two screws, pull out the part, then remove the wire.)
Would a pic of the face of the selector be possible?
Also a pic of the wires that lead to that fuse that the jumper box seems to be attached to.
There are voltage selector switches from parted out Sansui units all over the Internet.
Maybe the one used on the X1 was shared by other models.
Which would be something good to know.
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Here it is Ron same as my g9000, and g22000Great! New territory at last! Lots to figure out here, but that's the fun part.
Kale has actual experience with that part and it's function,
and so really would have the last word on this issue...but...I vote leave it.
I vote leave it because, if you have to actually undo that jumper,
you can just cut it off later easily.
Easier still if the selector is mounted on the outside of the chassis.
( In which case...Undo two screws, pull out the part, then remove the wire.)
Would a pic of the face of the selector be possible?
Also a pic of the wires that lead to that fuse that the jumper box seems to be attached to.
There are voltage selector switches from parted out Sansui units all over the Internet.
Maybe the one used on the X1 was shared by other models.
Which would be something good to know.
Ronito6
Super Member
I think I have it figured out one or more of the main capacitors on the right channel are bad.I replaced diodes and transistors on F- 2781 put everything back together plugged into the dbt flipped the switch and the light stayed bright then I unplugged the green transformer wires for the left side flipped the dbt switch and the light continued to stay bright plugged the green wires back in and unplugged the purple transformer wires to the right side flipped the dbt switch and the soft start relay clicked and the front panel lights came on so then it was a process of elimination unplugging wires and flipping the dbt switch to everything on the right side starting with the OPTs and seeing a bright bulb every time until I disconnected the center tap wires on the main caps and with everything connected back up except the center tap wires click it turned on.That my friends tells me that one or more of the main 10,000uf 80v caps on the right side are kaput..Niiiiice.
Thanks very much.
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Thinking about opening up the cans and dropping these in there.They'll fit right in and then run some solid copper wire to the contacts like Kale does or drill a few holes and then wrap and solder the copper wire directly to the steel contacts like I did on my G-9000..
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Ronito6
Super Member
Wow! Tame that beast!
Would you consider, as a trial measure just installing that new cap without gutting the old one yet. If it turns out not to be the problem you will have a path back.
Hyperion in his thread is considering which 10,000 80v filter caps to use in his machine.
I would go with Nichicon KG Gold Tune as they have very similar qualities to the originals. And as I mentioned in Hyperions thread: http://audiokarma.org/forums/index.php?threads/restoring-an-au-x1.709469/page-9#post-9790346
"Well maybe this might help.
I, in my obsessive wont, took the main filter capacitor mounting plate from my donor X1 down to my favorite parts shop here in Osaka.
They stock those big Nichicon KG Gold Tune filter capacitors.
I placed four of the Nichicons on the mounting plate and they all fit.
Double checking with my Vernier gauge, I measured the minimum width of the mounting plate to be 60 mm,
and the maximum width of the Nichicon KG Gold Tune is 50 mm.
So...if you are considering Nichicon KG Gold Tune, its do-able.
Perhaps with a bit of alteration to the mounting plates, but do-able."
The cap you show may not be up to the same quality as the one you are losing.
I'm not certain. You may wish to check opinions online.
HOWEVER It is certainly acceptable for proving your suspicions correct.
Well...go for it man!
Would you consider, as a trial measure just installing that new cap without gutting the old one yet. If it turns out not to be the problem you will have a path back.
Hyperion in his thread is considering which 10,000 80v filter caps to use in his machine.
I would go with Nichicon KG Gold Tune as they have very similar qualities to the originals. And as I mentioned in Hyperions thread: http://audiokarma.org/forums/index.php?threads/restoring-an-au-x1.709469/page-9#post-9790346
"Well maybe this might help.
I, in my obsessive wont, took the main filter capacitor mounting plate from my donor X1 down to my favorite parts shop here in Osaka.
They stock those big Nichicon KG Gold Tune filter capacitors.
I placed four of the Nichicons on the mounting plate and they all fit.
Double checking with my Vernier gauge, I measured the minimum width of the mounting plate to be 60 mm,
and the maximum width of the Nichicon KG Gold Tune is 50 mm.
So...if you are considering Nichicon KG Gold Tune, its do-able.
Perhaps with a bit of alteration to the mounting plates, but do-able."
The cap you show may not be up to the same quality as the one you are losing.
I'm not certain. You may wish to check opinions online.
HOWEVER It is certainly acceptable for proving your suspicions correct.
Well...go for it man!
If I went with those kg gold tunes you describe mouser is 12 weeks out
I think they're better then the original's and the way I do it they can be swapped out easily
And although I wired those caps on my g9000 in series the voltage's are nuts on..and I'll be rewiring them parallel as soon as this x-1 is off my bench..
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By the way I desoldered the jumper between 4 and 4 and put it how the schematic shows and it made no difference it work s the same either wayNiiiiice.
Thanks very much.
Ronito6
Super Member
Woooooo! You ain't mess'n around.
You will need to machine the original mounting plate to accept the fatter caps. Or have a new one fabricated that will accept them.
Don't forget, you will need 50mm brackets / braces for mounting. It will be a bit tight but all should fit similarly to the originals.
By changing those out you will be doing something no one else has done in an X1 restoration. It's kind of a student becomes the master moment. I can't wait to see them in action.
Special Note: Credit were its due...The mighty Oilmaster suggested those KGs to me ages ago when I considered changing my filter caps. He works in Tokyo with Nichicon as a capacitor specialist of some kind. I was very lucky to get his help at the time.
Anyway...while you are waiting for those Nichicons. You can still prove your filter cap theory with the one you got.
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Ronito6
Super Member
Well...you eliminated one possibility at least.
Can you do some voltage measurements to make sure both transformer primaries are energised? (Safety note: be careful probing around the voltage selector plug/socket).
I've just thought, resistance measurements will be best here, check the resistance of one primary, then with the jumper plug installed, check for ½ that resistance, but you might need to temporarily disconnect the primary of the square transformer.
Update
Willy, your pictures of the jumper socket and plug are very good, however the schematic picture of the socket does not reflect reality, which throws me/us a curve. I don't know what the internal connections of the jumper plug are, so all I can say is that on the multi voltage transformer the wires connected (for US mains) should be Blue & Orange (120V) and Yellow & Brown (0V) - this will ensure you are using both primaries.
The reason I am stressing the importance of this is that using only one primary may cause premature failure of the transformer, at the very least it will compromise the performance of the amp.
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If you look at my pics of the jumper plug I have the numbers 5 1 6 3 4 on one side and C C 4 2 C on the other side and where the wires are soldered on to the socket those numbers and letters are printed behind each contact and the color of each wire and which number they connect to on the schematic is exactly the same on the socket.Can you do some voltage measurements to make sure both transformer primaries are energised? (Safety note: be careful probing around the voltage selector plug/socket).
I've just thought, resistance measurements will be best here, check the resistance of one primary, then with the jumper plug installed, check for ½ that resistance, but you might need to temporarily disconnect the primary of the square transformer.
Update
Willy, your pictures of the jumper socket and plug are very good, however the schematic picture of the socket does not reflect reality, which throws me/us a curve. I don't know what the internal connections of the jumper plug are, so all I can say is that on the multi voltage transformer the wires connected (for US mains) should be Blue & Orange (120V) and Yellow & Brown (0V) - this will ensure you are using both primaries.
The reason I am stressing the importance of this is that using only one primary may cause premature failure of the transformer, at the very least it will compromise the performance of the amp.
I also did voltage measurements yesterday on both primaries and they were both energizedCan you do some voltage measurements to make sure both transformer primaries are energised? (Safety note: be careful probing around the voltage selector plug/socket).
I've just thought, resistance measurements will be best here, check the resistance of one primary, then with the jumper plug installed, check for ½ that resistance, but you might need to temporarily disconnect the primary of the square transformer.
Update
Willy, your pictures of the jumper socket and plug are very good, however the schematic picture of the socket does not reflect reality, which throws me/us a curve. I don't know what the internal connections of the jumper plug are, so all I can say is that on the multi voltage transformer the wires connected (for US mains) should be Blue & Orange (120V) and Yellow & Brown (0V) - this will ensure you are using both primaries.
The reason I am stressing the importance of this is that using only one primary may cause premature failure of the transformer, at the very least it will compromise the performance of the amp.
