What mods needed to amps for use in India

Discussion in 'Amps and Cabs [BG]' started by gshinde1, Jan 30, 2005.

  1. gshinde1


    Jan 30, 2005
    Hi Would like to know what mods I would need to make if I buy amp in US & take to India. Do let me know, will look back in this forum :bassist:
  2. IvanMike

    IvanMike TTRPG enthusiast, Happy, Joyous, & Free. Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    i'm guessing the only mod needed would be to adapt it to the voltage used there. most amps have adjustable (inside) power sources that can be switched from 120 v to 110 v to 220 v, and maybe something else as well. this generally accomodates the varying requirements of the US, europe, japan, etc.
  3. popinfresh


    Dec 23, 2004
    Melbourne, Aus
    What amps can be changed by a switch?

    I was looking at getting a GK (2001rb) or demeter pre amp sent over, but we run on 240 volts here. Apparntly i have to have the insides screwed with, and some people have had it go wrong, or it's gone good, but the tone is different.

    Is there really a big risk in getting the voltage changed around? Or what are some heads/preamps that can be changed easily. The only thing i don't like the sound of is no warranty..
  4. Or buy an external transformer to convert the 220 to 110...then just plug your US-bought equipment into the transformer. Only drawback is the extra weight, you're talking maybe 20 lbs to tote around.

    But no mods to equipment.

    Some (but not all) gear has an internal power transformer with two taps on the incoming power side: one for 110, then another for 220. Reconnecting the power supply cord to the proper set of taps (a couple of minutes of soldering) is all that's required. This would not affect the amp's tone at all, since it's done on the primary side of the transformer. Some gear makers go one step further, they put a switch on there to avoid the soldering hassles...but in today's cost-cutting world, dual-voltage power transformers and voltage selector switches aren't common.
  5. N*Joy


    Nov 30, 2002
    Birmingham, UK
    Eden world tour heads are switchable.
    Genz Benz GBE series heads I think detect voltage and switch automatically.
    Ampeg valve amps require a simple mod by a tech, solid states not possible.
    Some older Trace Elliot heads IIRC. I'm sure there are a few more but I can't think of any off the top of my head.

    You need a really beefy converter which can be a total pain in the ass.
  6. bmc


    Nov 15, 2003
    You should be able to buy a transformer in India. It will convert your head from 110 to 240. I have a few of them kicking around the house. It gets to be pain lugging around to gigs and you want make sue you plug into the right end of the transformer. Many of them have two small 1/8 inch holes that accomodate European style plugs. There is an "In" and an "Out" on these things. Also, they're not that big in size.
    You can get them modified in the US at the factory. Some do come with dual voltage capability by changing the fuse.
  7. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis
    As mentioned, voltage is the issue, but frequency is also an issue. US is 60 Hz, most other places are 50 Hz.

    The issues are different for units with conventional transformers as opposed to switchmode power supplies.

    Units with transformers.

    IF you buy a US model which cannot be internally switched to 220/240V, you probably have a "60Hz only" transformer as well.
    You cannot correct that by use of a 220/110 transformer. The "60Hz only" transformer will overheat (and fail faster) because it will draw more current, even at idle with no signal. Other related problems may also occur.

    If you have a US model with a 120/240 (115/220, whatever) transformer, you can have it re-connected for 220. There MAY be the need to replace fuses with lower values, as the higher voltage will require only half the current. The 120V fuses may be too large to properly protect the unit at the higher voltage, and they may or may not be rated for 240V (most are).
    But at least it can be done, and any 120/240 transformer should accept 50 Hz as well.

    BTW, essentially all recent Ampeg units can be re-connected for 100, 120, 220, 230, and 240V 50/60 Hz. No soldering, just move some wires and push-on connectors, and change fuses.
    Several other brands have the same easy changeover as well.

    Units with SMPS

    Some units with SMPS need to be re-connected for 220/240. This is normally either a switch, or a simple internal connection. Frequency is normally not a concern, although 50Hz may not operate to quite as low a low-line voltage.
    I believe QSC PLX and the Stewart amps are like this, for example....refer to their specs, however.

    A few SMPS (those with a so-called "Power Factor Controller in them), do not need to be switched, they can accept any voltage from about 85V to 265V with no concern for either voltage or frequency. This isn't yet as common, but is getting more so.
    In that case, all you need is the right line cord plug........

    A note:
    While a voltage switch is easy and not that expensive, it is becoming less popular. The reason is the safety agencies, like UL, or the european equivalent (VDE, Semko, SEV, etc).

    They demand that the unit be safe even if set for low voltage and plugged into the high voltage. While possible to accomplish, it is more expensive to provide that protection.

    And, "safe" does NOT mean the unit will ever work again after that. It only means that it won't catch fire, or cause a shock hazard, etc when it fails.

    The only way to escape that requirement is to either eliminate the switch, or make it acessible only with a "tool" such as having a cover requiring screwdriver to remove. obviously the economical way is to just leave off the switch, and require opening the unit to make the change.

    another note:
    Just changing the voltage does not necessarily mean that the unit then meets the details of the local safety code wherever you are.

    The unit when made for export to your country obviously has been tested and will meet all requirements.

    But if merely changed-over from a different version, while very unlikely to be actually unsafe, it may not meet the paper-work requirements locally. It may only be a matter of the markings or labels on the unit..... but you know how bureaucrats are, they love their "proper procedures".
  8. popinfresh


    Dec 23, 2004
    Melbourne, Aus
    What about Mesa? If i was to buy a 400/+ or 600 off ebay or even new and got it imported to Aus. Is all i would have to do is get the voltage changed with that simple step. Would it then be safe over here?

    Anyone know?

    And with eden world heads, so if were to get one from america,all i would have to do when it got to Aus is change the switch and it would be fine?
  9. Finger Blister

    Finger Blister

    Jul 8, 2003
    Problem Solved :D

  10. bmc


    Nov 15, 2003