Hi all,
Recently I bought a McIntosh MC275 valve amp.
My first question to the seller was "is it 120 volts or 240. (Australia has 240)
He assured me it was 240 volts. A week later I bought it.
It came with an Australian power cord (fits straight into our power points). (He could have just thrown that in easy enough)
On the chassis above the power input it states 110~120 volts. The print on the PT says the same. Also has a 4 amp fuse which suits USA voltage. (Aust 240v requires a 2 amp fuse).
Ok...
I have a stepdown transformer which I used but valves barely light up with next to no heat and sound is quite distorted with no power.
Could it be that it really is 240 volts. Not wanting to fry it I'm not going to try it, but it does seem like it's only getting half the required voltage 😕
So, at this stage it is in limbo. 🙁
Cheers,
Andrew.
Recently I bought a McIntosh MC275 valve amp.
My first question to the seller was "is it 120 volts or 240. (Australia has 240)
He assured me it was 240 volts. A week later I bought it.
It came with an Australian power cord (fits straight into our power points). (He could have just thrown that in easy enough)
On the chassis above the power input it states 110~120 volts. The print on the PT says the same. Also has a 4 amp fuse which suits USA voltage. (Aust 240v requires a 2 amp fuse).
Ok...
I have a stepdown transformer which I used but valves barely light up with next to no heat and sound is quite distorted with no power.
Could it be that it really is 240 volts. Not wanting to fry it I'm not going to try it, but it does seem like it's only getting half the required voltage 😕
So, at this stage it is in limbo. 🙁
Cheers,
Andrew.
On the choke L1, there should be 450Volts DC. If it is 250 ish, the transformer is running at half supply. Original 275s were 117/125 selectable mains input. NOT 240V.
I'm waiting to hear from seller. Just heard and this is his message -
"US suppliers, delivery before changed to 240V.
safe to use.
Do not have any concerns"
Would this be normal practice ? I'd have thought that if it were so then they would have stamped or put a 240v info sticker on chassis.
"US suppliers, delivery before changed to 240V.
safe to use.
Do not have any concerns"
Would this be normal practice ? I'd have thought that if it were so then they would have stamped or put a 240v info sticker on chassis.
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When the diagram is correct you should connect GRY/BLK with VIO/WHT.
Then the Black and White taps should give some 234 VAC.
Also try to check the negative supply for the power tube grids.
We have an MC275 (maybe older type) which had a prehistoric rectifier; negative grid voltage was quite a bit lower than the specified -57 volt so the power tubes draw too much current.
Then the Black and White taps should give some 234 VAC.
Also try to check the negative supply for the power tube grids.
We have an MC275 (maybe older type) which had a prehistoric rectifier; negative grid voltage was quite a bit lower than the specified -57 volt so the power tubes draw too much current.
OK, Thanks for the responses.
As I wrote above, the seller assured me it has been changed to 240v before it left USA.
I took him at his word, plugged 'er in the wall socket and Woohoo.... Running like a humdinger
Tubes lit up nicely.
It's getting late, I'll have to wait 'til tomorrow to let 'er rip through the Tannoys.
Andrew.
As I wrote above, the seller assured me it has been changed to 240v before it left USA.
I took him at his word, plugged 'er in the wall socket and Woohoo.... Running like a humdinger


It's getting late, I'll have to wait 'til tomorrow to let 'er rip through the Tannoys.
Andrew.
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