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The Acoustic Club

#5,606
StingRay85 said:
Have a lead on a 270 for cheap. Its imported from the US and still 110V power plug. Anyone knows if it the transformer has different taps and can be converted to 220V?
Click to expand...

Yes it does.
 

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#5,610
StingRay85 said:
Have a lead on a 270 for cheap. Its imported from the US and still 110V power plug. Anyone knows if it the transformer has different taps and can be converted to 220V?
Click to expand...

If that picture Tvrtko just posted is from a 270 or 370, then that's a new one on me -- I've never seen a 120V/240V selector switch in a 270/370. Prior to seeing that picture I was sure that Acoustic only started incorporating a voltage selector switch with the 450/470 and then carried it on in generation-3 models.

As the schematic someone posted shows, the 270/370's original design was for two different power transformers, a 4-wire version for domestic (540014) and a 6-wire version for export. The 6-wire export transformer part number is unknown to me -- the Acoustic parts list didn't list it separately, and in fact the 270's service manual parts description says erroneously that the 540014 is for 120/240. That error isn't in the 370 service manual.

I've uploaded a picture below of an export transformer in a 370 where you can definitely see one of the white center-tap wires coming out of the hole in the transformer shell. There's another picture below that is the back of an export 370 with a silver plate containing the alternate voltage lettering.

Bottom line: If the transformer only has two red and two black wires then it can't be switched or re-wired for 240V. You can however reconfigure the primary wires on a 6-wire transformer for 120V operation. I can't say with absolute certainty that Acoustic never used the 6-wire transformer in a late domestic production run, but I haven't run into one yet in any of my 270s or 370s. However I do believe they may have eventually switched later domestic 150-series models over to a 6-wire transformer, it's not impossible that they also did that with the 270 & 370.


370 EXPORT TRANSFORMER:
Xfmr.png



370 EXPORT BACK PANEL:
dscf3711i.jpg
 
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#5,613
Is there any way to pop it open quickly before buying to peek at the wires coming out of the transformer? You never know.

I dunno, there's some stray thought way in the back of my mind that I might have encountered a domestic 270/370 chassis with the white and black/white center-tap wires, but it could just as well be my over-active imagination. I just have a hazy memory of encountering the crimped wire-nut spllce on something I was working on a long time ago. Unfortunately I'm not able right now to open up what I have and see.
 
#5,616
I bought it in Germany from a home clean-out. Apperently there was still a bill of 400 usd with the amp, therefore I expect the condition is good. I have a 120-240V converter of 60W that I can use to see if it fires up and plays. Considering to use the transformer of my donor 220 if it matches the power.
 
#5,618
redstrand said:
Moved the 150 and 320 to the other side of the house and wouldn't you know it, no fuzziness. The electric in this house is something else. Guess I'll need a power conditioner...any suggestions?
Click to expand...

What do you want a power "conditioner" for?
 

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