Bad news is both units have the early mother board.
AU-X1
- Thread starter Willy6
- Start date
I'll post lots of pics when I can..
Ronito6
Super Member
Not bad news. Harolda has the same, and he can advise you how you can make your X1 nice and stable.
Apparently the source of the X1's instability was discovered by a tech in Germany, Martin Kuehne. Harold discovered his work.
Anyway, Mr Kuehne found that the source of the X1's oscillation problem came from bad grounding (for lack of a better description) on the 2819 flat amp.
Harold had a PM or two with Mr. Kuehne and applied Mr. Kuehne's grounding modification to his X1's 2819 flat amp board.
It is illustrated in his thread on posting #155 here http://audiokarma.org/forums/index....-output-transistor-replacements.684619/page-8
But to save you some time...
Wow.Thank you..Not bad news. Harolda has the same, and he can advise you how you can make your X1 nice and stable.
Apparently the source of the X1's instability was discovered by a tech in Germany, Martin Kuehne. Harold discovered his work.
Anyway, Mr Kuehne found that the source of the X1's oscillation problem came from bad grounding (for lack of a better description) on the 2819 flat amp.
Harold had a PM or two with Mr. Kuehne and applied Mr. Kuehne's grounding modification to his X1's 2819 flat amp board.
It is illustrated in his thread on posting #155 here http://audiokarma.org/forums/index....-output-transistor-replacements.684619/page-8
But to save you some time...
Ronito6
Super Member
onwardjames
and
JOMARK911
Sincerely...Your enthusiasm and encouragement is very much noted and appreciated.
Thanks!!
Definitely, however a step down transformer is quite a large expense if perhaps you won't be keeping the 100V model, so a variac may be more appropriate for you.
You will also need a 'DBT', the use of one after every major piece of work on the amplifier is extremely desirable.
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Or is that a bad idea?
No, I think that's fair enough, but remember - they are quite a handful, and this will complicate your restore.
Ya I was thinking if the transformers on the 78 one are good I could switch those and the power supply board.
It kinda looks like the square transformer on the 78 is bigger than the one on the 79.
Ronito6
Super Member
Kale swapped out the toroidal transformer in one of his X1 restorations. He upgraded one from a Japanese 100v version to a European 230v version.
It seems he changed only the toroid, but message him for details. Here is the thread http://audiokarma.org/forums/index....apan-to-export-model-plus-restoration.477461/
Keep in mind possible differences in the power switches. To play it safe I would use the US power switch too.
As long as I am on the issue of the power switch. The headphone switch is married to the power switch. So if you do swap out the switches that will be your chance to clean the headphone switch contacts. A bit of a hassle, but educational.
Kale has a relatively new website that specializes in Sansui parts.
He has NEW power switches for the X1 available. I bought one.
Here is the link http://www.sansui-vintage.com/product_info.php?cPath=13_22&products_id=112
Although his switches have the European double power contacts, they will work fine in Japan and US versions of the X1. In fact my X1 is now partly 230v ready should it end up in a 230v country. A worthy upgrade I think, and no hassles in needing to clean the headphone switch contacts.
Worth it!
It seems he changed only the toroid, but message him for details. Here is the thread http://audiokarma.org/forums/index....apan-to-export-model-plus-restoration.477461/
Keep in mind possible differences in the power switches. To play it safe I would use the US power switch too.
As long as I am on the issue of the power switch. The headphone switch is married to the power switch. So if you do swap out the switches that will be your chance to clean the headphone switch contacts. A bit of a hassle, but educational.
Kale has a relatively new website that specializes in Sansui parts.
He has NEW power switches for the X1 available. I bought one.
Here is the link http://www.sansui-vintage.com/product_info.php?cPath=13_22&products_id=112
Although his switches have the European double power contacts, they will work fine in Japan and US versions of the X1. In fact my X1 is now partly 230v ready should it end up in a 230v country. A worthy upgrade I think, and no hassles in needing to clean the headphone switch contacts.
Worth it!
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Thanks for the all the info.I'm planning on keeping the finished unit in my collection and since i have a parts unit ill prabably hold onto the power switch among other things so if something go's out I'll swap it when needed.
I did glance at both power switches and they looked to be the same.
I don't see why there would be a difference in the power switch between the different voltage models. The transformer should draw the same number of input watts regardless of input voltage. The input amperage for the 100v model would be higher than a 240v model. Most of the export models were multi voltage and the input power came through the same switch regardless of voltage setting.
If there is a difference in the power switch it's more likely a production change for cost, variability or cosmetics.
- Pete
If there is a difference in the power switch it's more likely a production change for cost, variability or cosmetics.
- Pete
