ET7 S2 transformer hum

[AnotherJohnson]

Vacuum the stat panels after leaving them unplugged for a few hours.

You’ve got at least one bad twin triode tube.

Who the h*LL is your dealer? Name names. Inquiring minds want to know.

[admin]

A new thing today..left Martin Logan 13a electrostatic Speaker emits very quiet crackling and clicking sounds.
Ear to speaker panel to hear it but it's there at times... it's inconsistent.
Only occasionally.

Then every hour or so....loud pops and bangs... from the left side.

Any chance there is static electricity? I presume everything is grounded correctly.

[Matty]

A new thing today..left Martin Logan 13a electrostatic Speaker emits very quiet crackling and clicking sounds.
Ear to speaker panel to hear it but it's there at times... it's inconsistent.
Only occasionally.

Then every hour or so....loud pops and bangs... from the left side.

Any chance there is static electricity? I presume everything is grounded correctly.

I believe so...

Did it 3 times today.... but not in the last couple of hours.

[admin]

Static electricity could be a potential cause of that random pop or crackle. Not sure where you are geographically but in the winter time I manually discharge the static on my equipment or else I get a shock when touching it the first time. In the summer. No such issues. You can try running a humidifier in the room to see if it alleviates the issue.

[Matty]

Vacuum the stat panels after leaving them unplugged for a few hours.

You’ve got at least one bad twin triode tube.

Who the h*LL is your dealer? Name names. Inquiring minds want to know.

So it's a KT120 causing the pops...
Or static build-up...?
Did sort of sound electrical but then again I guess it would, both the very very quiet crackling clicks and also the very loud pops and cracks...

Hasnt done it in last two hours....

[Matty]

Static electricity could be a potential cause of that random pop or crackle. Not sure where you are geographically but in the winter time I manually discharge the static on my equipment or else I get a shock when touching it the first time. In the summer. No such issues. You can try running a humidifier in the room to see if it alleviates the issue.

Central London

[roberto]

Hola Matt,
New stuff has sometime bugging issues...Usually having odd noises from the stat panel, two things can be:

1) A debris, the odd noise is located at certain point of the stat panel. With the help of a small brush, scrub a little bit at the front side only, use the vacuum cleaner, problem solved.

2) The other possibility could be the whole stat panel doing odd noise. When the noise is heard, stop the music, disconnect one speaker cable, any, the red or the black, and have a listen. If the noise remains, I suspect of the PCB (power supply board) of the speaker. Contact ML service dept. They will supply to you a new board, free of charge direct to your mail box or your physical address. I will take you 1/2 an hour to do the job. They will send to you the service procedure to it.
Matt, please, drink holy water...the bad ghosts are bugging you!

Patience, everything is going to be OK.

Happy listening!

[Matty]

Hola Matt,
New stuff has sometimes bugging issues...Usually having odd noises from the stat panel, two things can be:

1) A debris, the odd noise is located at a certain point of the stat panel. With the help of a small brush, scrub a little bit at the front side only, use the vacuum cleaner, and the problem is solved.

2) The other possibility could be the whole stat panel doing odd noise. When the noise is heard, stop the music, disconnect one speaker cable, any, red or black, and have listened. If the noise remains, I suspect the PCB (power supply board) of the speaker. Contact ML service dept. They will supply you with a new board, free of charge direct to your mailbox or your physical address. I will take you 1/2 an hour to do the job. They will send to you the service procedure for it.
Matt, please, drink holy water...the bad ghosts are bugging you!

Patience, everything is going to be OK.

Happy listening!

Thank you, Roberto.
The panels are very clean.
The shop's Demo units have been boxed in shop storage the last for a year, waiting for me to get back to London.
They ran them for a couple of hours to test them before delivery.

The loud cracks and pops were from the whole panel...Quiet clicks not so sure as extremely quiet.
The first time the loud cracks happened I instinctively turned everything off.
If it happens again I will try that....disconnect the red or black speaker cable.

The Art SA transformer has the loudest hum and seems a little bit louder after its been on a few hours I think

[admin]

Probably low chance, but have you checked your power? Any significant voltage regulation issues, poor grounding,... something like that? To have one issue is common, but you have significant hum in your preamp and amp, and also speaker issues that may be power related. Maybe there is a common thread here? Maybe try to move everything to a completely different circuit and see if it is reproducible on different wiring.

[AnotherJohnson]

From page 20 of the owner’s manual.

Popping and Ticking Sounds, Funny Noises
• These occasional noises are harmless and will not hurt your audio system or your speakers. All electrostatic
speakers are guilty of making odd noises at one time or another. It is the result of airborne contaminates (most notably dust). Vacuuming is recommended.
• These noises may be caused by dirt and dust particles collecting on the speaker, by high humidity.
• Dirt and dust may need to be vacuumed off. Please see the FAQ regarding vacuuming.

[AnotherJohnson]

Here is the vacuum info from the manual.

How do I vacuum my MartinLogan speakers?
Vacuuming will be most effective if the speakers have been unplugged for six hours to twelve hours (or over- night). You need not worry about the vacuum pressure damaging the "delicate" membrane. It is extraordinarily durable. Dirt and dust may be vacuumed off (don’t use a brush attachment) or you may blow them off with com- pressed air. When vacuuming or blowing off your panels do so to both sides, but focus the majority of your atten- tion on the front of the panels.

[AnotherJohnson]

Vacuuming is free. If they still snap and pop, look to the twin triodes in the amp.

[AnotherJohnson]

Since they’ve moved to Canada, the English part of the OM is not first, or even second.

But here’s the manual.

https://www.martinlogan.com/uploads/doc ... sl-13a.pdf

[Matty]

Vacuuming is free. If they still snap and pop, look to the twin triodes in the amp.

I had them on a while without audio as was watching the news on TV. So couldn't hear the speakers.
The speakers go on standby without input and the under-peaker light goes off.
However, the left was on.
Turned TV off and listen to the speakers....as said the left speakers light is on and its making a gentle hiss...a sort of quiet wind rush sound.
I tried unplugging black speaker cable and it went silent t but a gentle hiss started again as soon as it was plugged back in.
So the left speaker thinks it's getting a signal as the bottom light is on.
Gentle quiet wind hiss and tiny tiny quiet clicking

[admin]

I tried unplugging black speaker cable and it went silent t but a gentle hiss started again as soon as it was plugged back in.
So the left speaker thinks it's getting a signal as the bottom light is on.
Gentle quiet wind hiss and tiny tiny quiet clicking

Either something wrong in the input circuit that is activating the speaker even though it has no signal or perhaps a ground loop causing an "artificial signal"?

[AnotherJohnson]

Snap crackle pop or hiss are nearly always going to be either a small tube or the cleaning. Snap crackle pop are usually driver twin triodes in the amp. Hiss is usually the 6922 in the preamp.

Cleaning is free. But let them discharge before vacuuming.

If cleaning doesn’t do it, the twin triodes are next on the list.

RJ needs to make a trip to London to walk you through it.

[AnotherJohnson]

I had them on a while without audio as was watching the news on TV. So couldn't hear the speakers.
The speakers go on standby without input and the under-peaker light goes off.
However, the left was on.
Turned TV off and listen to the speakers....as said the left speakers light is on and its making a gentle hiss...a sort of quiet wind rush sound.
I tried unplugging black speaker cable and it went silent t but a gentle hiss started again as soon as it was plugged back in.
So the left speaker thinks it's getting a signal as the bottom light is on.
Gentle quiet wind hiss and tiny tiny quiet clicking

I had this light issue on my ML Theos once.
I called ML and they sent parts and advised on repair. It was not hard, but it was tedious. There were videos on their site at that time to walk you through it. Seems like there was a loose connection.

Your dealer is letting you down. Although I seem to remember that you mentioned an ML tech who might be willing to help. Call on him.

[Matty]

Thank you.
Yes, the KJwestone shop's Tech is coming Tuesday to check the speakers.

How do I check the power? For any significant voltage regulation issues and poor grounding?
What would I ask the tech guy to check or bring with him to check these things?
As he's coming anyway...

Is it possible the apartment building has no earth?
Built-in 1978... seems unlikely.
Pretty sure regulations came in the 1960s and the apartment has modern breaker switch fuse box consumer units with separate circuits for lights, kitchen, and wall sockets...

[AnotherJohnson]

So it's a KT120 causing the pops...
Or static build-up...?

No …
And … No.

The KT120s are Kinkless Tetrodes.

The 6922s are your twin triodes.

Static electricity is not an issue with the ML stat panels. ML says that higher humidity can cause noise … but it seems unlikely to be an issue during heating season.

[AnotherJohnson]

Thank you.
Yes, the KJwestone shop's Tech is coming Tuesday to check the speakers.

How do I check the power? For any significant voltage regulation issues and poor grounding?
What would I ask the tech guy to check or bring with him to check these things?
As he's coming anyway...

Is it possible the apartment building has no earth?
Built-in 1978... seems unlikely.
Pretty sure regulations came in the 1960s and the apartment has modern breaker switch fuse box consumer units with separate circuits for lights, kitchen, and wall sockets...

I assume you’re on 220 V 50Hz. In the US we have little gizmos that when plugged in the wall will tell you if the three wires are correct. I would think something similar would be available in the UK.

I don’t think your issue is bad power. A building built in 1978 isnt old by UK standards. In the US we had modern codes well before 1978.