Search results

T1 is the little PS transformer on the pcb. One half of T1 feeds the HV section directly, and the other half feeds the music sensor section and eventually switches on the Triac1 (and the main LED) which then completes the HV circuit. On mine the HV faded away slowly lowering the panel's output...

Yes! What's a hundred volts between friends?

You can check that one winding of T1 is outputting ~160VAC.

If you post the schematic for the Vantage HV supply, someone clever will tell you how to modify the sensitivity of the music sensor (iirc it's the ratio of two resistors) so it detects smaller signal, and then you won't have to hack them.

Buy used Ascent 'i' or Odyssey with the clear spar Gen2 panels. Get a demo beforehand.

One third the price: $2000 Prodigy https://sfbay.craigslist.org/sby/ele/d/sunnyvale-martin-logan-prodigy/7656046298.html

After the preamp, the signal is split: one to the main amp to passive high-pass xo-ESL as before, and the other goes through an electronic (active) low-pass crossover in front of the bass amp, which drives the woofer. Here's Rod Elliot's old bi-amping guide: https://sound-au.com/bi-amp.htm...

It's all I ever talk about: It's all that's missing from these original ESL hybrids to bring them up to the bass performance of today's ML's. You just have to wrap your head around how to insert an active xo in front of the bass amp, so the amp can drive the woofer directly....

You will need to look inside yours and see which version of SL3 it is. Just replace whatever electrolytics are in there, and be done.

Move up to Ascent 'i'! It fixes everything about the SL3 with a vengeance... https://www.usaudiomart.com/details/649907245-martin-logan-ascent-i/

You're in good hands with 'Bolserst' over there at diyaudio!

My recommendation was based on your previous post, so you should clarify more.

First I would suspect the transformer on the PS board. Since you have one working side, you should be able to compare. Many years ago one of mine went flaky and gave intermittent low levels: https://www.diyaudio.com/community/threads/ml-sl3-intermittent-bias-supply-problem.210168/#post-2973125

Until you find your glasses:

@DanR: Wasn't the trickiest part of converting yours deciding how to add the third pair of binding posts?

I am assuming the rear woofer does not play all the way up to the 250Hz xo point of the front woofer, but I don't know at what frequency the low pass point is in stock form. But once you go active you would set it to taste.

Simplified bass xo diagram attached. You will need a separate active xo and amp for each of the two woofers. The front woofer has ~80Hz high pass in addition to the main 250Hz low pass.

You made the right choice back then to get the SL3, as SL3 has the basics right and is two snips away from going active on the bass. When I went active xo on my SL3 (after wasting lots of time passive), I thought I had broken the laws of physics as the bass was so low and tuneful... But now I...

Is the room messing it up? If you slowly walk around in your room, does the bass get impactful anywhere else? What's it like right between the speakers?

I had not realized the Gen2 panels (identifiable by their clear spars) started this early, but the Prodigy was first with them, so these might be from the first year. Congrats on your purchase! So, when are you going active xo on the bass....?