The Workbench

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

SWISS_2 — Tue, 06 Oct 2009 00:31:12 GMT

Hallo Derek;

That is an enviable B&O collection you have.

Try FRY'S Electronics, or BEST BUY in North America.

Until you decide to solder or not, I might suggest you purchase a good converter ( Step-up, Step-down transformer ), and if you really like to crank up the volume ( and wattage ) a converter that has it's own built-in fuse.

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

auric — Thu, 01 Oct 2009 16:52:52 GMT

Menahem:

This is true!

But my wallet and time suffers!

Cheers,

Derek

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

yachadm — Thu, 01 Oct 2009 15:06:27 GMT

Derek

I think you're a sick man.

You definitely have the BeoVirus, and from what I've heard, it's incurable.

But at least the sufferer appears to have no negative side effects!

Enjoy it while you can.

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

auric — Thu, 01 Oct 2009 14:03:56 GMT

Hi Menahem:

I have several pieces of B&O:

BM 8000
BG 8002
BG 8000

Beocord 9000, 8002

CDX

BC 9500

BC 4000

BC 2500

BG 3400

BG 4002 (AC and DC motor version)

Only the BG 4002 has the voltage dial.

I live in North America.

B&O always used high quality transformers. I don't know if this is a European thing, but they B&O transformers have always looked more refined than transformers found in North American and Asian made equipment.

Many NA transformers are made rather sloppy from the windings to the the lumpiness of the varinish.

Just wish B&O had higher quailty epoxy glass circuit boards. This seems like a cost consideration as their more modern pieces have a hybrid of epoxy glass and phenolic type boards.

Derek

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

yachadm — Thu, 01 Oct 2009 02:00:22 GMT

At some point, B&O stopped including that voltage wheel on their products, preferring to make "market specific" products.

However, they continued to make the transformers "universal" - hidden benefit to us techies, but also a smart production strategy - one transformer for the whole world.

That means that by means of a few minutes soldering, the transformer wiring connections could be changed to suit the local AC supply. On my 1989 BeoGram 4500, the sticker clearly states 110V, but in less than 10 minutes, I had the transformer connections changed to suit our 230VAC, and if I wanted to sell it to a US BeOaddict (unlikely), I could resolder it quickly again.

I bought my BeoCenter 9300 (no voltage wheel) in 1995, from Frank Harvey in Coventry, and it states clearly on the rear sticker 240VAC. Obviously, I haven't had cause to change the voltage, but if I was to move to the other side of the pond (very unlikely), I'd investigate changing the wiring.

Modern (junk) switching power supplies easily handle a wide range of input voltages, but they are RF-noisy, and die quickly, with expensive repairs necessary. I rebuild SMPS's, and they are not on the market for quality purposes. It's like pumping the electronics full of steroids, and having them run 100m relay races for ever. Suddenly they collapse from intense exhaustion.

By comparison, a transformer supply is like the ancient mariner, sailing relaxedly on the open waves, with no stress. No wonder transformers last 70 years or more.

Menahem

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

BCubbins — Wed, 30 Sep 2009 17:27:32 GMT

I am quite sure you are quite sane; just as I am sure there is no wheel visable when removing the small panel over the transformer. I have even downloaded the Service Manual, and there certainly is no hint about a "US only" versus a "rest of the world" power supply. Interestingly enough, the PCB to which the power cord is soldered has the terminals identified as "Mains" - a term unknown on this side of the pond. And, try as I might, I could not get a photo of the power supply pasted in these pages; however, under BCubbins Files, I was able to upload a photo (it's pretty small, so it may not be of much use). I would be happy to email a photo to anyone (JPG, PDF or WORD) for their own edification or amusement.

Thanks again for all your help!

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

joeyboygolf — Wed, 30 Sep 2009 14:56:46 GMT

I assure you that the 9500's i've had, it's quite a few, have had a voltage selector wheel clearly visible in either a window in or under the panel. In fact, I have made a point of checking them since I had one which was set to 110 volts when I received it.

The dial is mounted on the mains transformer!

Just to prove that I am not senile, I just checked a 9500 in sales stock and it has the dial behind a window cutout.

You seem to have a wrong 'un or later production run or something weird.

Or, original US spec models are different!

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

BCubbins — Wed, 30 Sep 2009 14:13:44 GMT

Many thanks for the suggestions and information (and quick replies, too). Wanting to believe that B&O might have anticipated customers moving about the world, it only makes sense that B&O equipment be automatically voltage sensing. But, maybe in 1991, only laptop computers (e.g. my company Dell) could do that? In any event, a switch (as joeyboygolf) states above would be a reasonable solution. Ah, if it were so! I took off the little panel (held on by 2 screws) after reading his reply, and...nope, no switch - and I really wanted to find one. No amount of desire revealed a switch that would be accessible by removing that little panel (if I could figure out a way to paste a photo in this post, or attach a photo, I think I could prove my point).

So, "joeyboygolf," is the switch you allude to inside the carcass?

Again, thanks for the help.

It does certainly seem that, in any event, I should upgrade my membership in this forum and download the manuals (definitely cheaper than paying the "local" B&O dealer!)

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

joeyboygolf — Fri, 25 Sep 2009 16:39:10 GMT

The BC9500 has a voltage selector switch at the rear. It may be covered by the removeable rear panel (held on by 2 screws)just above where the mains cable enters the unit.

Simply select the appropriate voltage and replace the panel, chop the plug off of the cable and fit the correct one for your region.

I have no personal experience with Beolab3 but the service manual shows a simple jumper that needs to be added to convert from 220v to 110v. Then change the plug as above.

Simples!!

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

Premiumverum — Tue, 22 Sep 2009 03:10:14 GMT

I don't have a service manual for the 9500 handy, but I seem to remember a picture from some B&O service manual saying how to 're-wire' a transformer for other net voltages. Didn't seem hard to do, and certainly not like a 250 dollar conversion!

Check a service manual, or maybe someone here knows how to do this. Not sure it can be done with the 9500 transformer though!

Re: Convert from 220v to 110v - Beocenter 9500 & Beolab 3

SWISS_2 — Mon, 21 Sep 2009 16:37:50 GMT

From your description, it sounds like the external transformers are a better option for you. You would need a simple step-down transformer ( 240-to-100v ) for each European, or European-configured stereo products.

I have used external step-up/step-down transformers for years with B&O equipment. No problems ever, providing the transformer is of good quality.

Unless your item is actually true Multi-region powered ( 110-240 V, 50-60 W ), for example a Beosound 3 or Beosund 6, it will not play correctly for you. Repairs on B&O equipment as you mention can be truly expensive: My wife can verify that fact.

Convert from 220v to 110v - Beocenter 9500 & Beolab 3

BCubbins — Mon, 21 Sep 2009 16:14:03 GMT

I have a Beocenter 9500 (purchased in Seattle in 1991) that was converted to 220v in Budapest (by the dealer there) about four years ago (I then moved to Rome and it continued to work fine). While in Budapest, I purchased a pair of Beolab 3 speakers that also worked fine in both cities. I am now back in Seattle (to stay).

The retailer from which I bought the Beocenter says I have to take the stuff to the dealer in Portland to have the conversion done. I hesitate to think of the cost (the retailer technical department estimated $250 just for the service - any parts would be additional), let alone the time lost (two days worth of travel).

The panel on the back of the Beocenter into which the power cord enters (measures about 4 inches by 5 inches, held on by two very small screws) shows that the (two wire, no "ground") power cord is soldered to two printed circuit board terminals marked "Mains." The original 110v power cord is two-pronged (no ground there, either). I have not opened up the speakers.

My question is this: can I simply snip off the plugs (for 220v) off the power cords for all three pieces and put on plugs for 110v? In other words, will the equipment automatically sense the voltage input and (while protecting itself) convert to the correct input (line) voltage, or do I actually have to remove and replace (R&R) the internal power supplies?

If the internal power supplies cannot handle this scheme, then I will just use external transformers - I'm not spending hundreds of dollars, and several hours worth of driving time (since I do have transformers).