SL3 - One Panel Weak?

[xenonaut]

I recently picked up a pair of SL3's in Germany. The build date for the speakers is Spring 2000, though I'm told they were first sold new about 3-1/2 years ago. I'm not yet 100% sure that it's not my imagination, but it seems to me that one panel is weaker than the other.

Is there an easy test to see if this is indeed the case (I don't have an SPL meter or anything)? If it *is* the case that one panel is weak, is this a common failure, and is there anything to do except replace the panels?

Thanks in advance,

Hal

 

[DTB300]

Is there an easy test to see if this is indeed the case (I don't have an SPL meter or anything)? If it *is* the case that one panel is weak, is this a common failure, and is there anything to do except replace the panels?

Switch speakers around and see if less sound moves with speakers.

If the SL3's are like the Sequel II's (SL3's replaced Sequel II's), you can switch electronics and see if the sound changes or stays with the speaker. This will verify if it is electronics (crossover and/or power section for panel) or the panel itself.

If it is the panel, you can also think about washing/rinsing the panels (See tweak section here on ML Cleaning Service). This worked for me and my Sequel II's, but you can also purchase new panels from ML. Not sure what SL3's run, but Sequels are around $500, so I would imagine SL3's to be slightly more.

Dan

 

[xenonaut]

Switch speakers around and see if less sound moves with speakers.

If the SL3's are like the Sequel II's (SL3's replaced Sequel II's), you can switch electronics and see if the sound changes or stays with the speaker. This will verify if it is electronics (crossover and/or power section for panel) or the panel itself.

If it is the panel, you can also think about washing/rinsing the panels (See tweak section here on ML Cleaning Service). This worked for me and my Sequel II's, but you can also purchase new panels from ML. Not sure what SL3's run, but Sequels are around $500, so I would imagine SL3's to be slightly more.

Dan

Hi Dan,

Thanks for the reply.

Swapping the speaker positions was the first thing I tried. The "weakness" did seem to follow the speaker. I will try listening to some test tones to try to verify the difference; listening to music, it's really hard to be sure.

If it seems that I'm right about the difference (and my gut tells me I am, though I want to verify that as scientifically as possible), I'll try swapping the electronics next, and then try washing the panels, I suppose (although it's not clear to me why one panel would be "dirtier" than the other). There was some controvery about whether it was safe to wash the back sides of the panels; do you have any advice on that?

Thanks again,

Hal

 

[dyazdani]

Not sure what SL3's run, but Sequels are around $500, so I would imagine SL3's to be slightly more.

I checked earlier in the year and the SL3 panels were $500 as well (in the US anyway).

I thought I needed some, but a good vacuuming made them good as new.

 

[DTB300]

I checked earlier in the year and the SL3 panels were $500 as well (in the US anyway). I thought I needed some, but a good vacuuming made them good as new.

Another great suggestion by Dyazdani, is the vacuum work...make sure you have tried this too. Unplug before going to bed or work, vacuum, plug back in, listen.

I rinsed both sides of my Sequels when I did it. I believe both side is used only when the panels, like the CLS, do not have the extra pieces on the panel for ridgidity or mass. My Sequels did not have any of these extra pieces on them, and since the SL3 has a similar panel, it may be ok. But take a look and see if extra pieces are there.

But to be sure, give ML a call and ask.

 

[aliveatfive]

As I posted earlier, Sequel II panels are no longer manufactured as such. If you order them, you will get SL 3 panels. They are interchangeable.

 

[dyazdani]

I thought that was the case, but couldn't remember for sure.

Thanks for adding that piece of information.

 

[amey01]

I recently picked up a pair of SL3's in Germany. The build date for the speakers is Spring 2000, though I'm told they were first sold new about 3-1/2 years ago. I'm not yet 100% sure that it's not my imagination, but it seems to me that one panel is weaker than the other.

Is there an easy test to see if this is indeed the case (I don't have an SPL meter or anything)? If it *is* the case that one panel is weak, is this a common failure, and is there anything to do except replace the panels?

Thanks in advance,

Hal

The best way to verify whether one panel is weaker than the other is to play mono pink noise and it will be apparent where the image comes from as to if one panel is weaker than the other. This may also be in a certain frequency range, so also play pink noise in only one channel at a time and see if you can hear a pitch shift between them. Hope this helps.

 

[Kruppy]

I've had what seems to be the same issue with my SL3's. The soundstage tends to lean to the left speaker over time. It becomes quite noticeable. As soon as I vacuum them the image is centered. As posted earlier, I would first give them a good vacuuming.

 

[Jeff Zaret]

Hal,
All of hese suggestions are great and right on. I am hoping that one of these will work for you without having to buy new panels. Of course buying new panels is always nice too.
One other thing and it is remote but may also contribute to the lesser sound of one side and that is the placement of the speaker. You might have one side that is more reflective than the other. This would be like a window or slidng door by one speaker and a wall or a large book case along a wall on the other side.
These are just things to consider and I am sure you have looked at this too.

Good Luck

Jeff

 

[xenonaut]

<snip>
One other thing and it is remote but may also contribute to the lesser sound of one side and that is the placement of the speaker. You might have one side that is more reflective than the other. This would be like a window or slidng door by one speaker and a wall or a large book case along a wall on the other side.
These are just things to consider and I am sure you have looked at this too.
<snip>

Hi Jeff,
Thaks - yes the first thing I did was swap the speakers, to rule out (a) differences originating in any upstream components and (b) effects of the room. My impression is that the wekness travelled with the speaker.

The best way to verify whether one panel is weaker than the other is to play mono pink noise and it will be apparent where the image comes from as to if one panel is weaker than the other. This may also be in a certain frequency range, so also play pink noise in only one channel at a time and see if you can hear a pitch shift between them. Hope this helps.

Aha - I was hoping for a tip like this. I tried listening to sine waves, but it's really hard to tell, because the phase effects of the room make the amplitude very dependent on exact position of the listener's head. Pink noise could be helpful. I suspect that the weakness is only in a certain frequency range, not overall. Thanks.

I'll try vacuuming and then maybe giving them a little shower.

If it seems like just a certain frequency range is weak, is it still possible that this is linked to the electronics and not the panel itself? Anybody have any theories on what would cause wekness in a particular frequency range, either as a fault in panel or electronics?

Thanks to everyone for all the great comments so far - I very much appreciate all the help.

Hal

 

[amey01]

Hi Jeff,

If it seems like just a certain frequency range is weak, is it still possible that this is linked to the electronics and not the panel itself? Anybody have any theories on what would cause wekness in a particular frequency range, either as a fault in panel or electronics?


Hal

I guess you could always try putting the panels back in different speakers after a wash and see what happens. That will be a sure-fire way of telling whether it is the electronics or the panel. But hopefully after all that your problems will be solved! Good luck!