Issue with Martin Logan Aeon i

[Sughosh]

Fellow ML community,

I just ordered my first ever pair of electrostatic speakers a couple days ago from an audio vendor on eBay. When it arrived, there was no damage to the box nor to the speakers and everything was mint. However, when I plugged in the speakers (currently from my Denon AVR 1612), the blue LED only lit on one of the speakers, so the mids/highs were not in balance but the woofers were fine. However, if I increase the volume by 5.5 dB on the non-lit speaker, the sound is balanced and there is equal sound coming from the ESL panel. Also, on a random occassion, the blue LED did light up on the problem speaker and everything was balanced w/o +5.5 dB.

What do you think is causing this issue? I checked the mains and there is power, and I tried different speaker wire, to no avail.

Thanks!

 

[roberto]

Hola Sughosh. You have a PSU problem. You have to do some test and exchange or swap parts from one speaker to the other. Can you do this? Exchange the PSU (power supply unit) and check if the problem changed. If it is so, then you found the culprit of your problem. To do this, first of all, turn off all your system, and disconnect the speaker wires and the power cord. You have to open the back of your Aeon I, and the board that it is attached to the back plate (the back of the speaker). You can follow the connection wires from the Mains A.C. socket. Usually colors are green, black and white. Copy exact the connection wires to the PSU board, take a pic and follow just the colors of the wires when installing them back again. Coming from the speaker connectors, there is a very thin wire, (gray). This wire is the one that activates the sensing circuit and turns on the stat panel high voltage, when the music is present at the binding posts. One side is copper color, and the other is silver color...watch carefully the colors when re-install again. If the PSU is, contact ML for a new one. It is difficult to track the problem, but a good technician could repair it. Happy listening!

 

[Tosh]

An intermittent problem like this is going to be extra tricky to track down. But I would start by opening the cover and making sure every connector is tight and that all screws are tight. Hopefully something just came loose during shipping...

 

[Sughosh]

Thanks for the replies! To remove the back panel, do I just need to remove the 10 screws on the back? Or do I have to remove the spikes on the bottom, etc? Thanks.

 

[roberto]

NO..sometimes the back panel stays sticked to the speakers cabinet. With the aid of a rubber mallet, you can hammer on the back panel hard in different sections of the back panel, until it gets loose. Or, you can remove the woofer at the front, and with a log, where you can hammer on, you can loose it. (please excuse my English). Good luck on this task!

 

[Sughosh]

I opened the back cover and did not notice anything disconnected. Do you see anything I might have missed?

 

[roberto]

Exchange the PSU boards, and tell us your findings!

 

[Tosh]

The intermittent symptoms you're describing are what happened to my SL3. If I gave the back panel a whack, they would power on again, until one day they stayed off. Then I determined it was the on-board transformer (not the audio step-up transformer), got a new one and a spare from ML for $16 each, replaced it, and they were good again....

 

[Sughosh]

Thanks all! I will replace and circle back!

 

[Tosh]

Whoa there! You need to determine what's actually wrong on your own speakers....