European/African voltage guitar amplifiers???

[Bill Ashton]

A friend has a friend coming to visit, who wishes to buy an electric guitar and amplifier for his two boys...for use in Kenya where apparently the mains voltage is 240 VAC. Any ideas on something domestically available which would be switchable to use when they go home?

Probably has to be pretty small, as it has to go back on the plane as well...

I thought of maybe a Crate Taxi or Vox DA-5 that runns off a wall-wart, and found a 240 volt
adapter at Zzounds, but there has to be a better answer. If switchable out of the box, I would think that switching out the power cord plug should be within the skills of the father.

Ideas gentlemen, ideas????

 

[coastie99]

Weber, and others, have replacement "International" transformers available, at no huge cost. https://taweber.powweb.com/store/magnetic.htm

Not difficult to figure out compatibility with a non-Fender amp. and certainly not a particularly daunting task carrying out the swap.

 

[SFIV1967]

Yes, there are amps with switchable AC 110V/220V power supply that would work in Kenya.

Here is just one amp example, I am sure when you search on the internet you find more.

http://www.amazon.com/gp/product/B000E1 ... ative=9325

http://www.sears.com/shc/s/p_10153_1260 ... 34387288-2

Ralf

 

[Ian]

I know it's rumoured in valve amplifier circles that another transformer before the amplifier (as in a step up or step down transformer), is a good thing sonically. I have never heard a technical explanation of why this might be so, but it certainly seems to be a well recited urban myth...

Cheers, Ian

NB: perhaps some of the newer digital amps which use switch mode power supplies might be suitable ? Dont know what they sound like in guitar amplifier applications though...

 

[capnjuan]

I know it's rumoured in valve amplifier circles that another transformer before the amplifier (as in a step up or step down transformer), is a good thing sonically. I have never heard a technical explanation of why this might be so, but it certainly seems to be a well recited urban myth...

Hi Ian; you may be confusing step-up / step-down transformers with a Variac ... shortened from 'Variable AC':

Step up/down voltage transformers do just that; take wall voltage from US nominal 110V (or Euro 230V) and change it up to 230V or down to 110V. Back in the day, US domestic electrical voltage was +/- 110V but today in most areas of the US, the voltage is closer to 117-120 volts.

The variac in the pic can control output voltage from 0 to 130 volts AC; it's a piece of electronic bench equipment but since it can vary the voltage to the amplifier, some players use them to starve an amp for voltage producing a noticeable change in tone ... more of the 'Olde Tyme' thing; brown-sounding distortion and crunch.

Say you had 100 watts of screaming Marshall power and lived in a 1 bedroom apartment; you could starve the Marshall for voltage getting the good stuff at something like 2/3 on the dial. That's the good news; the bad news is that prolonged play at reduced voltage will mess with bias and otherwise shorten the useful life of the output tubes.

I use the one in the pic to reduce the local 117V down to 110V - the design voltage for my ragamuffin Gibson amps - and to safely form new power supply capacitors by bringing the voltage up slowly instead of slamming them with full voltage using the 'on' switch. Although it's generally accepted 'web-law' that you don't really have to do this is, that view is most widely held by those who've never had a cap blow out at power-up.

If you did confuse the transformers for the variac, a former US major league baseball player, facing charges for using banned performance drugs, referred to this phenomenon as 'Mis-remembering'. :wink:

 

[Ian]

Hi John, Nope no dis remembering here: I know what a variac is , techies use them for powering up old valve amps that havent been used for a while, watching where the smoke comes from etc, right ? So I take it that you hadnt heard of the transformer before the amp being a good thing sonically ? I'm suprised....

Cheers, Ian

 

[capnjuan]

Hi John, Nope no dis remembering here: I know what a variac is , techies use them for powering up old valve amps that havent been used for a while, watching where the smoke comes from etc, right ? So I take it that you hadnt heard of the transformer before the amp being a good thing sonically ? I'm suprised....

Hi Ian: I guess it's me that's mis-remembering. :wink: Step up/down transformers and variacs came to mind when you mentioned transformers ahead of amps.

The only other application I can think of is isolation; say down NZ way, the power is 'dirty' ... has all kinds of stray currents or hash in it. If you had a 230V-in / 230V-out transformer, that transformer would prevent electrical fuzz from appearing in the amp's power transformer and on its ground. In this sense, I'm not sure the transformer makes the amp sound better, it would make it sound like it's supposed to.

But maybe instead of guessing, I'll just ask the question; what are you talking about?

 

[Ian]

Hi John,

That's just it mate, wouldnt have a clue what I'm talking about really... It's just one of those things that gets mentioned from time to time by guys who seem to know what they are talking about: that a transformer before the amp makes it sound better....

(to be blunt if you are running a US voltage amp with a 240/110 transformer in front of it, Its kinda difficult to disprove as you cant just plug tha amp into the wall socket to compare can you :lol: ). As I said it's just one of those urban myth type of things that seems to have become rooted as fact. Technically you are quite correct in that all the other transformer might do is to clean up the power supply..

Sorry to muddy the waters, seems it must be a NZ thing if you guys havent heard the theory ?

Cheers, Ian

 

[capnjuan]

... That's just it mate, wouldn't have a clue what I'm talking about really... (to be blunt if you are running a US voltage amp with a 240/110 transformer in front of it, Its kinda difficult to disprove as you cant just plug that amp into the wall socket to compare can you :lol: )

:lol: I guess not :lol: Although the step-down transformer would do the same thing an auto-transformer (230V in / 230V out) ahead of the amp would do ... extract hash out of the power. Anyway, if you run across reference to it on the web, send me the link!

 

[archtopbob]

Acoustic Image are dual voltage amps. I'm in the UK on 240v AC.

Bob :idea:

 

[SFIV1967]

@archtopbob: I just think it is a fair guess that the price range of "Acoustic Image" amps is far beyond what the gentleman in Kenya wants for his two boys. At least as it sounded to me.

Ralf

 

[Bill Ashton]

Ralf, sorry to be so long in answer to your first message, but I passed those two links along to the friend whose friend is visiting...get that? :lol: I thought those were perfect for their purpose.

I found several Crate amps that say they are dual power but do not show switching, so I suspect you have to order which mains you want and we'd never get a 220/240 here.

Bob, if I were traveling to Kenya, that AI amp is what I would want! Though I must agree probably not right for the boys that like Green Day and metal. But thank you for your suggestion.

If anyone comes up with another commerically available amp I would like to see it, as my internet search has been rather disappointing.

 

[capnjuan]

Hi Ian; another stab at your 'urban myth' ..

a discussion of Eddie Van Halen using a Variac Text below edited:

"Amplifiers

... Rumors have abounded about the amplifier being heavily modified and some of these rumors were in fact generated by Mr. Van Halen himself ... However, in truth according to our best knowledge, his amplifier of choice for recording, a mid-60's 100 watt Marshall Super Lead ...

First, he used an Ohmite [manufacturer] Variac, a variable transformer that could lower or raise the voltage going into the amplifier. Edward set the variac to approximately 90 volts, thereby reducing the amount of input voltage going to the amplifier and allowing the amp to run more reliably. A key element often not considered today when running vintage Marshall amplifiers is that many that were made for export to the U.S. were designed to run at 110 volts and current U.S. outlets run at 120 volts. As a result, while there has been much talk about the dangers of using a variac, in many applications, it obviously serves a benefit." ... and so on.

More techno-discussion on Variacs and Marshalls here.

Not sure if this is what you're thinking of or not.

 

[archtopbob]

@archtopbob: I just think it is a fair guess that the price range of "Acoustic Image" amps is far beyond what the gentleman in Kenya wants for his two boys. At least as it sounded to me.

Ralf

My comment was merely to demonstrate that amps are available without the need for a transformer. I can't imagine the likely buying power of anybody flying to the US from Kenya. .

Bob

 

[SFIV1967]

@archtopbob: True, I was just guessing.
Ralf