Acoustic Research amplifier 220v

[EastPoint]

Hi folks. I picked up an old Acoustic Research amplifier today. It is marked as a 220V unit on the back, which I noticed after failing to get it to run off of 120v current. In order to get this running, can I get a $30 converter on eBay and run it with that? I just want to test it—this isn’t for long-time use.

 

[cademan]

Converters do work and I have used them, but unless you have the money to buy a real good step up transformer with all the filtering and all, in my experience, cheap one's just introduce all kinds of noise and/or hash.

If you are so inclined, maybe look into wiring a dedicated outlet from your dryer or hot water heater circuit. I did this for an SAE amp a few years ago and it worked great but I used a different plug and receptacle so no one else including myself, could accidentally plug in any other US made appliance. Worked great but then sold the amp. Now I have a dedicated 240 outlet for any stuff I might find at the thrifts with 220/240 volt inputs.

 

[sregor]

All the old AR amps (universal or multi voltage) I saw had multiple windings in the transformer, and could be converted to 110 by moving wires in the amplifier. Check page 43 of the service manual (at hifiengine,com - free but must register.) AFAIK they didn;t make a 220 (or 240) only versions, but I could be wrong....
Also, most converters do not work well with amplifiers, and are not recommended. Step down or internal conversion is best way to go.

 

[bimasta]

most converters do not work well with amplifiers, and are not recommended. Step down or internal conversion is best way to go.

Agree, and with some experience. I was living abroad, in 220V country. An acquaintance was importing Acoustic Research amps/preamps as an entrepreneurial venture, about 10 of each as I recall (late 1980s). One or two 110V models were sent by mistake. We tried a stepup transformer, and it was an excellent one: borrowed from a nuclear power station, where cost is no object when safety is concerned. The 110 amps did not sound nearly as good the 220s. He called the owner of Ac Res in the US, who explained the added transformer acted as a "choke", restricting frequency response and dynamics — exactly what we were hearing. He sent new transformers of the right voltage, and they were great again.

 

[EastPoint]

I rewired it for 120v according to the manual, but it's still not working. When I turn it way up I get faint distorted sound on both channels, but that's it.