Hi All, I Forgot to mention I'm in New Zealand an local supply for transformers etc is very limited (if at all), plus we use 230V here. If any one may know where there maybe some 230V medallion transformers laying around would you please let me know.
I'm guessing a bias transformer would also need to be 230V?
Much thanks for your help.
I'm guessing a bias transformer would also need to be 230V?
Much thanks for your help.
Dallyboy: the Medallion transformers aren't specified with respect to the supply line voltage, only the bias transformer is. The Medallion transformers are strictly step up for the audio signal and are completely independent from supply voltage. There's a vendor on US Audio Mart selling entire Medallion transformer interfaces as well as individual HF Medallion transformers.
A more economical solution would be to use a step-down transformer from your local mains voltage to the specified voltage of the interfaces you have. A fifty-watt transformer, or even smaller, would be sufficient to power both interfaces. Or you can use two step-down transformers, one for each speaker. This may avoid cords running across the floor!
Thanks for your help guys. The bias transformers are 240v now so no need for a step-down
unless they are stuffed and I can’t find a suitable replacement then hello 120v. I forgot the medallions are step up trans. Such a long time since my last pair.
I did what Acoustat Answer man suggested and after repairing a few contacts I powered the interfaces up. After 5 hours off charge I discovered the following.
Both speakers have low output from the two bottom panels from both interfaces.
One interface has distorted bass with some popping, changes to other speaker if I swap interface.
Other than that the mids and tops are good from both the interfaces. And bass in fine from one interface.
So what maybe the reason for the low output from the bottom panels and the distorted bass?
Thanks again for you time and help guys, much appreciated.
unless they are stuffed and I can’t find a suitable replacement then hello 120v. I forgot the medallions are step up trans. Such a long time since my last pair.
I did what Acoustat Answer man suggested and after repairing a few contacts I powered the interfaces up. After 5 hours off charge I discovered the following.
Both speakers have low output from the two bottom panels from both interfaces.
One interface has distorted bass with some popping, changes to other speaker if I swap interface.
Other than that the mids and tops are good from both the interfaces. And bass in fine from one interface.
So what maybe the reason for the low output from the bottom panels and the distorted bass?
Thanks again for you time and help guys, much appreciated.
In the 2+2, all panels are driven equally, so if you have a difference between top and bottom panels, then you have a panel or wiring issue. Of course, make sure you really do have a difference: room acoustics can play tricks on our ears. Look for bad connections/pinched wires at the interface and along the length of wires running up to the panels. You could have bad panels, but the chances of all four bottom panels going bad are pretty slim.
Distorted bass from one interface only points to a bad low frequency transformer (largest of the three). If the transformer has a break-down in its insulation, it will arc internally and cause distortion and popping noises. Beware – this problem will only get worse, and could damage your amplifier, especially at high levels.
I don’t have much energy anymore for detailed troubleshooting here, but I can help if you can provide some more clues.
Distorted bass from one interface only points to a bad low frequency transformer (largest of the three). If the transformer has a break-down in its insulation, it will arc internally and cause distortion and popping noises. Beware – this problem will only get worse, and could damage your amplifier, especially at high levels.
I don’t have much energy anymore for detailed troubleshooting here, but I can help if you can provide some more clues.
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Thanks for your input AcoustatAnswerMan, very much appreciated.
I thought the distorted bass may be the low frequency transformer playing up. Bummer. I will have to hunt around for another or can they be rewound / copied by a local transformer company?
The low output from the four bottom panels is very odd, as you say having the 4 panels go bad is weird.
They were in a lockup, a shipping container, for many years and I don't feel it was flooded at any point as everything else that was in there had not showed signs of flooding.
I'll check the wiring again for any issues. Fingers crossed its not the panels, if so they will become 1+1's
I thought the distorted bass may be the low frequency transformer playing up. Bummer. I will have to hunt around for another or can they be rewound / copied by a local transformer company?
The low output from the four bottom panels is very odd, as you say having the 4 panels go bad is weird.
They were in a lockup, a shipping container, for many years and I don't feel it was flooded at any point as everything else that was in there had not showed signs of flooding.
I'll check the wiring again for any issues. Fingers crossed its not the panels, if so they will become 1+1's
Ok, I've checked all the wiring to the four panels using my one good working interface an found no issues with the wiring, at least none that I can see. But I did find that one bottom panel is dead. Most of the coating has come off. The other bottom panels still sound down compared to the top panels. Can't figure out why.
So out of the 8 panels, 3 are down on volume and 1 is dead. Looks like I will be changing these guys into 1+1's after all.
Just need to get the LF transformer replaced for the other interface and I will be good to go.
So out of the 8 panels, 3 are down on volume and 1 is dead. Looks like I will be changing these guys into 1+1's after all.
Just need to get the LF transformer replaced for the other interface and I will be good to go.
Whoops, looks like you already swapped the interfaces...and issue remained with interface.
I would check the bias voltage on both too - if you have a bad diode or capacitor on the bias ladder, you could be low on bias voltage on the bad interface...causing distorted bass...
And be extremely careful as these are 5000vdc interfaces...
I would check the bias voltage on both too - if you have a bad diode or capacitor on the bias ladder, you could be low on bias voltage on the bad interface...causing distorted bass...
And be extremely careful as these are 5000vdc interfaces...
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Thanks John for you thoughts.
I've tried the not so good interface on the other speakers and found it gave the same distorted bass to all the panels. I'm thinking of cutting the wiring to the dead panel at the interface end and see what that does to the remaining panels.
I get good mids and tops from the top two panels from both speakers with both interfaces.
As far as checking the bias, I only have my voltmeter, how does one do this? I'm no tech
Cheers
I've tried the not so good interface on the other speakers and found it gave the same distorted bass to all the panels. I'm thinking of cutting the wiring to the dead panel at the interface end and see what that does to the remaining panels.
I get good mids and tops from the top two panels from both speakers with both interfaces.
As far as checking the bias, I only have my voltmeter, how does one do this? I'm no tech
Cheers
Unplug interfaces - wait half hour for all high voltages to drain.
Pull three panels wires from the interface. On the center red connection - in socket where bias wire pin goes, test here. Put Voltmeter on dc. Power up interface, wait couple minutes to stabilize, then measure that middle connection at the socket...with ground (black probe) on bare metal nut or bolt on transformer screw.
Should get around 70 -75 vdc (at least I did with my DMM, but I may have a different impedance, so compare voltages between good interface to bad interface).
If bad interface has lower than good interface - that MAY have been problem. Be careful as these are high voltage...
Pull three panels wires from the interface. On the center red connection - in socket where bias wire pin goes, test here. Put Voltmeter on dc. Power up interface, wait couple minutes to stabilize, then measure that middle connection at the socket...with ground (black probe) on bare metal nut or bolt on transformer screw.
Should get around 70 -75 vdc (at least I did with my DMM, but I may have a different impedance, so compare voltages between good interface to bad interface).
If bad interface has lower than good interface - that MAY have been problem. Be careful as these are high voltage...
Hello All,
Buying a pair of One Plus Ones with the red medallion upgrades. Have to transport them 600 miles to their new home. I'm concerned about damaging the frames during transport. Any suggestions ? I'm vacillating between building a crate for each , to cutting down cardboard boxes to support the towers . Thoughts? thanks!!
Buying a pair of One Plus Ones with the red medallion upgrades. Have to transport them 600 miles to their new home. I'm concerned about damaging the frames during transport. Any suggestions ? I'm vacillating between building a crate for each , to cutting down cardboard boxes to support the towers . Thoughts? thanks!!
Sorry...I forgot to add that both have the 121 interface, so it is not an apples to oranges debate between what is behind the panels. Thanks!