ESL 9 hissing and levels

[Ishaansuri]

I am running ESL 9's with McIntosh mc301 monos.

Recently I added a feya plus with electroharmonix tubes.

Question 1
Both my panels have developed an audible static hiss recently. It is on different spots on each panel Audible when your ear is placed close to it. Did a vacuum clean already. Panels stay covered 100% when not in use and are very clean.

Hiss is audible only when there is no music playing and everything is mute. The hiss stays if I turn off the amps and preamp. It's a static electric hiss not a room filling one. Like a high pitched frying electric hiss.

It goes away after few minutes of panel discharge. It goes away after a min or so after i unplug the power supply of the panels.

Question 2
I sometimes feel the center image shift to right after 30 mins of use.

Sometimes I turn everything amps preamp off on and it is back to normal again. This method needs more tries to be sure but i noticed it fix one time.

Speakers are 2 years old
I previously had both my panels replaced by ML as my original panels had shown a noticeable db level diff and my bias boards had also had some problem with their capacitors. Once the panels were replaced around 6 months ago all has been well until recently introducing the Freya plus and tubes where I notice both hissing and the occasional level drop. Level drop is consistent with tubes engaged and disengaged in the Freya.

Was using mc301 pair with an emotiva preamp previously.

Recently I also noticed one day the sound is also on the extremely bright to crispy side compared to normal smooth tones.

Anyone know what might be going on.
Panels ?
Amps?
Preamp?
Quality of power ? Not using a conditioner.

They are driving me crazy.

Thoughts appreciated

 

[ttocs]

I'd suspect the amps first, but an easy first step is to swap left and right stuff.

First, try swapping only the speaker cables at the amp outputs. Nothing else, just the amp outputs.

If the anomalies change from right to left then you know it's an amp or preamp problem.

 

[msimanyi]

Perhaps he edited his message, but he says the hiss is present even if the amps and preamp are powered down.

If they're powered down and off for 5+ minutes, do you still hear the hiss or is it present only briefly after powering off the preamp and amps? You mention the speakers are 2 years old, but they've already had the panels replaced and some capacitors as well. Did you buy the speakers new? Are they still under warranty?

I'm surprised they've had so much work done already. It's possibly the speakers again, but I'd look into your electronics first and ttocs' suggestion should help drill into the problem.

The fact that the hiss isn't across the entire electrostatic surface seems... unusual to me. I'd expect the hiss to be present across the entire surface. Whether or not you're in the U.S., you might want to contact ML directly and speak with them about the issue.

Regarding question 2, that's a tough one. It could be the tubes in your Freya coming up to temp. It could be they're aging and need to be replaced. It could be the speakers.

If it's the tubes, try swapping the two in the right bank on your Freya+. If the same thing happens but the shift goes the other direction, it's probably worth trying some different tubes. (To be honest, I'm not impressed with the new Electroharmonix tubes. I use a Freya+ in my office setup and they were marginal when I tried them in late 2020.)

 

[Ishaansuri]

Thanks.. speakers were new but had some initial problems possibly due to being in distributor storage over lockdown. I purchased them late 2020 post lockdown. I'm in New Delhi India. ML does give me warranty on the replaced panels. ML usa says hiss is normal.

Let me try some of these first steps and report back.

Shall try one move at a time with playback sessions over a few days with the swap in place.

Let me know if steps in this order make sense.

1. Tube input stage L R swaps to rule out the weakest link in tube first. The Freya is new was added 1 month back. But i hear the shift and hiss even with solid state mode. Tubes disengaged.
2. Then cable end swap on monoblocks
3. Complete preamp swap back to the old emotiva which was working fine after panels were changed with no hiss or shifts. (Should i just make this step 1?)

I do suspect panels at first due to their previous history but I will try to arrive at them last as i want to believe they are not going to die out again in just 6 months with marginal east listening.

 

[msimanyi]

I think I'd move #3 to #1. Let us know what happens.

 

[Leporello]

The fact that the hiss isn't across the entire electrostatic surface seems... unusual to me. I'd expect the hiss to be present across the entire surface.

No! you'd hear it where arcing is occurring.

There may be two different problems going on, but definitely with the panels. Local arcing is a dead give-away. Isn't there some kind of warranty on panels that new? Do you have a different pre you could try? (Around here I have 4 Adcoms and a Cambridge. I really should try the free classified ad service here).

It's also possible your bias supplies are over-volting, but that doesn't seem very likely. Do you live in a particularly humid area?

Decades ago, one of my Acoustat panel's started making a faint squealing sound. Unlike ML, you can't see the stators and diaphragm without removing the grill. Also unlike ML, Acoustat recommended you leave them fully biased all the time. Eventually, the noise just went away.

I see now you live in New Delhi. I think that qualifies as high humidity. You may want to bypass the music detection circuitry and just leave them biased all the time, and clean them when they get dusty. Or just live with it.

If it's also the source of the image shifting, then different story. Of course that's not livable. But do rule out the electronics. You don't hold onto any of your old stuff? Shame on me, I guess.

 

[Ishaansuri]

No! you'd hear it where arcing is occurring.

There may be two different problems going on, but definitely with the panels. Local arcing is a dead give-away. Isn't there some kind of warranty on panels that new? Do you have a different pre you could try? (Around here I have 4 Adcoms and a Cambridge. I really should try the free classified ad service here).

It's also possible your bias supplies are over-volting, but that doesn't seem very likely. Do you live in a particularly humid area?

Decades ago, one of my Acoustat panel's started making a faint squealing sound. Unlike ML, you can't see the stators and diaphragm without removing the grill. Also unlike ML, Acoustat recommended you leave them fully biased all the time. Eventually, the noise just went away.

I see now you live in New Delhi. I think that qualifies as high humidity. You may want to bypass the music detection circuitry and just leave them biased all the time, and clean them when they get dusty. Or just live with it.

If it's also the source of the image shifting, then different story. Of course that's not livable. But do rule out the electronics. You don't hold onto any of your old stuff? Shame on me, I guess.

Not particularly in a humid area, not near the ocean but it's been humid for a few weeks as it rains on off ..mostly it's dry here. The hiss i hear is a like an insect squealing hiss on particularly 1 area on each panel. The hiss responds to pressure from my fingers and taps. It tends to change in volume or frequency when I do this. It's loud enough that in a quiet room i can hear it from a foot away from the panels.

I also hear this hiss while music is playing when I place my ear on the spot during a quieter piece of music. I can hear it in there.

It is also there when speakers are completely disconnected from the amps and just powered using their charge adapters. So this mostly rules out the amps or pre

 

[Leporello]

I see now you posted about your previous problem. Sounds to me as if you got a pair of lemons, and ML ought to be talking about replacement speakers. It happens. Perhaps bias supplies were the cause of the panel problems after all. Also, I've expressed my opinion elsewhere about running panels on power conditioning, but you might want to check that your line voltage isn't far above whatever the standard in your country is, and that they're configured properly for that voltage (the latter responsibility should rest squarely on the dealer's shoulders).

 

[Ishaansuri]

I see now you posted about your previous problem. Sounds to me as if you got a pair of lemons, and ML ought to be talking about replacement speakers. It happens. Perhaps bias supplies were the cause of the panel problems after all. Also, I've expressed my opinion elsewhere about running panels on power conditioning, but you might want to check that your line voltage isn't far above whatever the standard in your country is, and that they're configured properly for that voltage (the latter responsibility should rest squarely on the dealer's shoulders).

I've ordered a power conditioner from audioquest, a pq3 sonwiol see if that helps. On my previous thread and problem they changed the panels and boards although not in my presence. Had speakers sent to dealer for this. They don't do speaker replacement in my country. I do have warranty on my new panel repair I'm guessing i will inform them about this so it's recorded before the period ends.

 

[Robert D]

If I were you, I'd get some kind of dehumidifier. See if that helps after a week of running.

Is your home air conditioned?

 

[Ishaansuri]

If I were you, I'd get some kind of dehumidifier. See if that helps after a week of running.

Is your home air conditioned?

Hi Robert
Hope you have been well.
Apparently ML USA says this is a normal occurance due to dust and to do a vacuum clean. I tried that not much diff will try again. My speakers stay covered 100% of the time when idle. I possibly play them 30 mins a day and more on weekends. Room is primarily dust free and air conditioned although don't have the ACs on 24x7.

But you remember what happened last year when they gave me new panels and boards on these. They ran fine and still sound good.

I did some tweaking on placement to rule out level issues, am still investigating that observation. It maybe just a panic reaction basis the history.

The hiss is a regular feature as soon as they come alive.

See screenshot for reply from ML

 

[Robert D]

Hi Robert
Hope you have been well.
Apparently ML USA says this is a normal occurance due to dust and to do a vacuum clean. I tried that not much diff will try again. My speakers stay covered 100% of the time when idle. I possibly play them 30 mins a day and more on weekends. Room is primarily dust free and air conditioned although don't have the ACs on 24x7.

But you remember what happened last year when they gave me new panels and boards on these. They ran fine and still sound good.

I did some tweaking on placement to rule out level issues, am still investigating that observation. It maybe just a panic reaction basis the history.

The hiss is a regular feature as soon as they come alive.

See screenshot for reply from ML

Wow, thats news to me. My speakers dont do that. Ive never heard of that before. Maybe some others can add to the conversation. Hopefully everything is ok with all of your equipment.

Ive been doing ok here. Just tired of this terrible inflation on everything. How is it in India?

 

[Ishaansuri]

Wow, thats news to me. My speakers dont do that. Ive never heard of that before. Maybe some others can add to the conversation. Hopefully everything is ok with all of your equipment.

Ive been doing ok here. Just tired of this terrible inflation on everything. How is it in India?

Things are well. Good to hear you're keeping well. Inflation discussions on another thread haha

Equipment is doing well. Just added a feya plus with tubes along with the mc301 pair. Really enjoying the sound, expecting some 6sn7GTB NOS soon. Great little product.

Just very skeptical on longetivity on these speakers occasionally especially keeping in mind their history. My other speakers have lasted decades and behave mint. These need to live up to it. It's hard to imagine not having them. Nothing sounds like a ML ESL.

 

[Robert D]

Things are well. Good to hear you're keeping well. Inflation discussions on another thread haha

Equipment is doing well. Just added a feya plus with tubes along with the mc301 pair. Really enjoying the sound, expecting some 6sn7GTB NOS soon. Great little product.

Just very skeptical on longetivity on these speakers occasionally especially keeping in mind their history. My other speakers have lasted decades and behave mint. These need to live up to it. It's hard to imagine not having them. Nothing sounds like a ML ESL.

My experience with Martin Logan is decent. The only product I had issues with was my Decent subwoofer. It developed a ticking/thumping sound that would come and go very sporadically. I replaced it last year with a BF 210 and its been very good so far. My experience with subs is that they certainly dont last a long long time.

My Prodigy speakers sound great and I bought new panels for them 2 years ago I think, lost count of time! Even the old panels that were down many db in sound never made the hissing sound you describe. The new ones dont have that sound either. I also owned a theater i center that I sold and replaced with the Focus. It has never made the sound either.

 

[Robert D]

My old panels needed to be replaced when I bought them in 2014. So they were about 14 years old then. They were produced in 2000. I did not replace them until 2020. Should have done earlier, but I was ignorant about electrostats and did not know better. They still sounded good to me.

 

[roni44]

I would take a flash light and inspect every corner of the panel make sure nothing stuck in between the panel. I live in Taiwan and can get humid and dusty, my current pair EM ESL does not hiss at all, previous pair of Clarity was dead slient as well until my son tipped over the speaker. Luckily damage was minimal only an inch dent which created hiss. If you can isolate the hiss sound, most likely you can address the problem.

 

[Ishaansuri]

Hey Roni

Yes i already tried this couldn't find anything. They look clear as new but maybe there is something inside the edge behind the frame. But both speakers have similar characteristics so it's fairly consistent here.

Also as an update ML has officially emailed me and asked me to move my ESL power adapters and plug them via a power conditioner. Going to try that today and to vacuum the panel a few times.

They else have asked me to record a video of the sound and send it to them.

Let's see what happens with these steps.