Focus C18 Stat Panel Not Working

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ttocs

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The stat panel has very little, or no output. This results in muffled sound, especially noticeable with voice, and is easily seen with REW sweeps which show huge drop-off between the crossover points.

The blue Status LED lights up, and I checked the voltage of the power adapter to be 15VDC, but didn't bother to check the output Current because only 0.15A is required.

I vacuum the front of the Focus when I vacuum my Expressions. But unlike the Expressions, the stat panel of the Focus is not directly accessible due to being a distance behind the front perf screen that is mounted all across the front of the speaker, and I don't know of a way to remove the front perf screen.

Anyone else have the stat panel on the Focus fail to have full output?

This is the first over over 20 ML products of mine to have a failure.

I sent a Support request for repair.
 
The stat panel has very little, or no output. This results in muffled sound, especially noticeable with voice, and is easily seen with REW sweeps which show huge drop-off between the crossover points.

The blue Status LED lights up, and I checked the voltage of the power adapter to be 15VDC, but didn't bother to check the output Current because only 0.15A is required.

I vacuum the front of the Focus when I vacuum my Expressions. But unlike the Expressions, the stat panel of the Focus is not directly accessible due to being a distance behind the front perf screen that is mounted all across the front of the speaker, and I don't know of a way to remove the front perf screen.

Anyone else have the stat panel on the Focus fail to have full output?

This is the first over over 20 ML products of mine to have a failure.

I sent a Support request for repair.
Is it still under warranty? Luckily mine is fine.
 
Yes, it's under warranty.

My first guess is something is wonky in the internal power supply section.
Second guess is something might have failed in the crossover, but I would think this is pretty unlikely.
I'm thinking something in the internal power supply parts seems most logical. Ron at ML can help you. If you bought it local then you should be able to drop it off there and they can fix it. I've done that with a Depth i sub.

All of the parts are very modular now and it will probably just require changing out a board.
 
I'm thinking something in the internal power supply parts seems most logical. Ron at ML can help you. If you bought it local then you should be able to drop it off there and they can fix it. I've done that with a Depth i sub.

All of the parts are very modular now and it will probably just require changing out a board.
It was Ron who responded at the start of business today. Very quick response indeed!

I indicated that I am capable of disassembly and electronics checking, and that I would prefer not to have to ship the speaker. So he gave me instruction to measure the stat power supply, which means I had to order a resistor that I don't have. The resistor is necessary to allow for measuring very high voltage in the range of 1700-3000VDC. None of my meters can go over 1000V, so I'll have to wait for the Wells Fargo Wagon to deliver the resistor. Digi-Key is usually pretty quick and usually gives me a choice on shipping speed, but no choice this time so it'll be whatever "Marketplace Standard" means. Being that it's a Holiday Week, who knows? So I'll have to be patient and expect it'll be a week or so.
 
It was Ron who responded at the start of business today. Very quick response indeed!

I indicated that I am capable of disassembly and electronics checking, and that I would prefer not to have to ship the speaker. So he gave me instruction to measure the stat power supply, which means I had to order a resistor that I don't have. The resistor is necessary to allow for measuring very high voltage in the range of 1700-3000VDC. None of my meters can go over 1000V, so I'll have to wait for the Wells Fargo Wagon to deliver the resistor. Digi-Key is usually pretty quick and usually gives me a choice on shipping speed, but no choice this time so it'll be whatever "Marketplace Standard" means. Being that it's a Holiday Week, who knows? So I'll have to be patient and expect it'll be a week or so.
Thats great you have the knowledge and experience to test it on your own. I was lucky with my depth i sub that I was able to just hand it over to the dealer and they did it all. My BF 210 I bought from DaVinci Media and so I wasnt able to do that because they arent local to me. Ron at ML took care of it all for me and sent me parts, and when that didnt work he had me send them the sub and I got a brand new one. Ron was a pleasure to work with. Shawn at Davinci Media is a great guy too.
Be sure to keep us all updated, id really like to know what went wrong with yours, in case it happens to me. It sounds like youll have it fixed soon enough.
 
Well Ron to the rescue!!
He's shipping out a new HV Power Supply! Seems like the most likely source of the problem.
So I won't need to wait for the resistor, and in fact he suggested that I cancel the order.

This is the only warranty issue I've had with over 20 ML products. I've been very impressed with the after-sale support over the years, but this is way over the top in Customer Support! Very happy!
 
Well Ron to the rescue!!
He's shipping out a new HV Power Supply! Seems like the most likely source of the problem.
So I won't need to wait for the resistor, and in fact he suggested that I cancel the order.

This is the only warranty issue I've had with over 20 ML products. I've been very impressed with the after-sale support over the years, but this is way over the top in Customer Support! Very happy!
Yeah, Ron treated me with great respect and was very friendly. It makes me want to continue buying their products. I just wish that the inflationary prices weren't so bad. It's not just them though, it's everywhere.
For me, Martin Logan is good proof that you get what you pay for. That's hard to find these days.
 
I was going say contact Martin Logan and Ron and once you’re in Ron‘s capable hands you will be taken care of with efficiency and grace. He really is the best. And by the time I saw this post and was able to respond he had already taken care of you!
 
Ron sent the HV Power board and it arrived today!
The new board is installed and the Focus is working again!!

Thanks Ron at ML Support!!!
That's awesome. How hard was it to install? Im guessing Ron sent you detailed instructions on how to do it, complete with pictures? ML does a good job of that. The speaker seems like its sealed up pretty good. How did you gain access to the inside?
 
A few things just for the record.

As with any electronic item, caution must be used! I use the One Hand Rule when poking around in anything electrical. If one doesn't know what this rule is, then one should learn the value of it before tackling anything dealing with electrical items. There are many instructional sites and videos detailing why this is important.

Using the 1000MegOhm resistor, measuring the old HVPS (High Voltage Power Supply) resulted in erratic output readings. The voltage bounced around in the millivolt range, and the bouncing was in a rhythmic, repeating pattern.

Once the new HVPS was installed, it measured 23.5VDC with the resistor in-line with the meter which equates to an actual 2350VDC, very stable and right in the middle of the expected range. Big difference, eh?
 
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That's awesome. How hard was it to install? Im guessing Ron sent you detailed instructions on how to do it, complete with pictures? ML does a good job of that. The speaker seems like its sealed up pretty good. How did you gain access to the inside?
It was easy. But I'm used to tinkering with things.

Ron sent detailed info with photos for getting into the back of the speaker and noting the connectors involved.

In my case I only needed to remove the connectors on the HVPS board.
 
It was easy. But I'm used to tinkering with things.

Ron sent detailed info with photos for getting into the back of the speaker and noting the connectors involved.

In my case I only needed to remove the connectors on the HVPS board.
Usually, can't you just let the gear sit unplugged for a period of time and that will discharge the energy stored in the capacitors? I'd probably wait 24 hours just to be safe. The charge wouldn't remain longer than that would it?
As a child, I got curious and took a Poloroid camera apart and I touched a capacitor I guess because it shocked the hell out of me! I wasn't cautious because I figured a battery powered item couldn't pack a punch. I was wrong! I figured having the batteries out was good enough, lol. My dad who was an electrical engineer filled me in later, lol. I was about 9 years old.
 
Usually, can't you just let the gear sit unplugged for a period of time and that will discharge the energy stored in the capacitors? I'd probably wait 24 hours just to be safe. The charge wouldn't remain longer than that would it?
Some circuits are designed to discharge capacitors, like some old guitar amps which can drain the caps when power is removed. Even so, I still measure the caps to verify that no volts remain.

If there is any question as to if voltage is being stored anywhere in a circuit, assume it is, then safely verify. This means that I don't use two hands with a probe in each that can potentially COMPLETE the circuit should some unfortunate circumstance be presented.

How long a charge can remain depends on the circuit. Old CRT's could store very high voltage for very long time. The rule for these is to always discharge even if it's been sitting around for years.
 
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