Markbass CMD121P change voltage from Europe to UK

[moncur]

Hi guys,

Having a few sound issues with my Markbass CMD121P at the moment, and looking to eliminate any possible issues before taking it to my amp technician (100 miles away as I live in the middle of nowhere).

I've already invested in a HT-30 tweeter to solve the well known tweeter issue. Hoping to install it this week.

However, my main concern is the fact I bought the amp from Thomann, and not a UK shop, and therefore the voltage has been set for Europe and not the UK. I know for most electrical items this would not be an issue, but apparently it is if you buy a Markbass amp.

Whilst having a nose inside the amp, I noticed this bit....
[attachment=230289:image1.JPG]

Is it a simple case of move the jumper from the middle (CN3) to the bottom (CN1)? Or is there any other steps I need to follow?

Cheers, Richard

[bumnote]

[b] What are the differences between 220VAC, 230VAC and 240VAC Mains Supplies and what voltage equipment should I use?[/b]

[color=black][size="2"]For many years, mainland Western Europe has used a mains electricity supply rated at nominally 220VAC 50Hz. The UK used 240VAC 50Hz.[/size][/color]

[color=black][size="2"]Currently, ALL Western European supplies are classified 230VAC. In reality there is no 230VAC supply unless you create one locally. 230VAC was a “standard” created during European "harmonisation" to give a single voltage standard across Western Europe, including UK and Irish Republic.[/size][/color]

[color=black][size="2"]Although the ideal would have been to have a single voltage there were too many political, financial and technical obstacles to reduce UK voltage to European levels or to increase European voltage to UK levels, so a new standard was created to cover both. This was achieved by changing the tolerances of previously existing supply standards. UK voltage to 240VAC + 6% and - 10% and European to 220VAC +10% and -6% (thereby creating a manageable overlap) and we would call these two combined 230VAC, despite the fact that nobody was intentionally generating at 230VAC![/size][/color]


[color=black][size="2"]Depending on the voltage sensitivity of the product and the variance from nominal of the actual supplied voltage, it may not be advisable to use a 220VAC specific device in the UK or a 240VAC specific device in Mainland Europe etc. For instance a 240VAC supply can rise to as high as 254.4VAC and still be within tolerance, but the maximum rated voltage for a 220VAC product is only 242VAC. A 220VAC supply can drop as low as 206.8 within tolerance but the minimum rated voltage for correct operation of a 240VAC product is 216VAC It may work perfectly well either way but it could be, technically, outside the specification of the equipment with obvious implications. A 230VAC product must be compatible with all voltages across this range[/size][/color]

[color=black][size="2"]If a product is to be used in the UK a 240VAC rated device is ideal but either 240VAC or 230VAC products can be used with confidence.[/size][/color]

[machinehead]

I can't see well enough to see what the links are doing. In theory European and UK voltages are the same. In practice they're not, but they're close enough not to worry.

If it was mine I'd leave it as it is.

But unless you're certain and know what you're doing, leave well alone or take it to a good repair man for advice.

Frank.

[molan]

I asked exactly the same question about a Gallien Krueger head last week as they also say that individual heads are set to either European or U.K. Voltages.

Their tech people said it was fine to use their MB heads anywhere across Europe and UK.

[Hobbayne]

Would it it be worth getting one of those travel plugs to use on it?

[pete.young]

MarkBass themselves say that resetting the operating voltage is a job for their service centres.

That bottom jumper says 120V - I'd be wary of going anywhere near that unless I was absolutely certain it wasn't going to cause the thing to be set to US voltage.

Also worth noting is that if the amp is still under warranty you will invalidate it by messing with the voltage selection.

[moncur]

Cheers for the advice guys, I'll email Markbass to see if they have any further comments on the voltage issue. If I'm able to post video, I'll try put up some clips of the sound issues I'm currently having. It is just outwith the 3 year warranty so I'm quite happy to take it to my own repair guy from now on instead of shipping it for a service.

[markstuk]

[quote name='moncur' timestamp='1476877119' post='3157965']
Cheers for the advice guys, I'll email Markbass to see if they have any further comments on the voltage issue. If I'm able to post video, I'll try put up some clips of the sound issues I'm currently having. It is just outwith the 3 year warranty so I'm quite happy to take it to my own repair guy from now on instead of shipping it for a service.
[/quote]

Has it always had problems? Or have they started recently? If recent, then the voltage setting is probably unrelated..

[moncur]

When I first bought the amp, I sent it back to Thomann within a few months as it stopped sending signal to the speaker (DI still worked though). And then a year or so later the DI failed whilst the Amp continued to function otherwise, it was sent back again just before the warranty ran out. Now when I turn the EQ controls beyond say 3 o'clock (no gain, volume or anything plugged into the input), I get feedback in whichever tone is being adjusted. I'll post a video later.

Edited October 19, 2016 by moncur

[yorks5stringer]

The voltage red herring has been aired on here a number of times due to the disclaimer on the MB site which really only applies to importing US market items in EU countries where the voltage is markedly(!) different.

I had a LMII bought in France for many years, the only issue was that the UK distributer would not touch it under warranty, had to send it back to French Retailer who sent it to the French distributor for warranty work..when I dropped it!

Think you've just got a rogue head, leave the voltage alone!

[moncur]

Update: In the end I got in touch with Real Electronics, as the feedback issue was doing my head in.
They picked up the amp on Monday, switched the voltage over, and discovered it was the preamp that needed replacing. My amp is now on it's way back up the road. I really can't fault them on their high level of service.

[Musicman20]

REAL are excellent....just the service you want when things go wrong.

[ambient]

I thought Thomann offered a free 5 year warranty ?

Edited October 27, 2016 by ambient

[yorks5stringer]

3 years I think?

[moncur]

aye it's a 3 year warranty they have. Got the amp home last night, sounding far healthier now. Glad that I changed the tweeter over, it's much quieter than the stock tweeter.

[yorks5stringer]

The other option is to just disconnect the stock tweeter. I can live without it!

[ras52]

Out of interest (with apologies for slight hijack), where's your amp technician? I have a bought-secondhand out-of-warranty CMD121P with a not-working DI out. I'm on the London/Kent borders and it would be good to drop it off somewhere by car rather than lugging it into central London by public transport!