Hi,
For a while I've been deep diving in refurbished ESL 63/988 (can't afford any of the successors). Aside from the numerous debates between believers and non-believers, I'm a believer... I'm a particular fan of the staging depth and transparency of the quad with concentric delayed rings on the stators. The only issue, for me, is the height of the stereo image. I find it simply too low and my room does not allow for raising them sufficiently, due to a slanted roof.
Now here comes my question: Did anybody try to switch the "mid-high" panels on top of the 2 "bass" panels (in case of the 4 panel variants)?
It seems so obvious... but I can't find any information of this "tweak" being done before by someone. Or am I a total shmuck overlooking some fundamental aspects...?
Please feel free to share any thoughts/experience.
Many thanks!
M
For a while I've been deep diving in refurbished ESL 63/988 (can't afford any of the successors). Aside from the numerous debates between believers and non-believers, I'm a believer... I'm a particular fan of the staging depth and transparency of the quad with concentric delayed rings on the stators. The only issue, for me, is the height of the stereo image. I find it simply too low and my room does not allow for raising them sufficiently, due to a slanted roof.
Now here comes my question: Did anybody try to switch the "mid-high" panels on top of the 2 "bass" panels (in case of the 4 panel variants)?
It seems so obvious... but I can't find any information of this "tweak" being done before by someone. Or am I a total shmuck overlooking some fundamental aspects...?
Please feel free to share any thoughts/experience.
Many thanks!
M
When changing panel configuration you break the d'Appolito configuration.
The description:
"The D’Appolito design aims to improve the directivity and dispersion of sound waves from the speaker, resulting in a more accurate and detailed soundstage. A big advantage is, that the configuration reduces reflections from the floor and ceiling, giving you a more focused and directional sound with fewer room interactions".
Image height to my opinion is mostly influenced by the way it was recorded and mixed, you have no influence on that.
I also found that some audio gear has influence on how well height information is passed and presented, DAC for instance.
You can use stands for both types of speakers.
But ..... the the biggest difference might be how the speakers are refurbished as precision is key to get the ultimate result out of the virtual point source principle. That makes better staging depth, transparency and height information more obvious.
I live in the Netherlands near the Belgium border. Feel free to visit and have a nice discussion about the subject.
You can see and hear our Quad ESL-63 work and how that performs. PM me.
The description:
"The D’Appolito design aims to improve the directivity and dispersion of sound waves from the speaker, resulting in a more accurate and detailed soundstage. A big advantage is, that the configuration reduces reflections from the floor and ceiling, giving you a more focused and directional sound with fewer room interactions".
Image height to my opinion is mostly influenced by the way it was recorded and mixed, you have no influence on that.
I also found that some audio gear has influence on how well height information is passed and presented, DAC for instance.
You can use stands for both types of speakers.
But ..... the the biggest difference might be how the speakers are refurbished as precision is key to get the ultimate result out of the virtual point source principle. That makes better staging depth, transparency and height information more obvious.
I live in the Netherlands near the Belgium border. Feel free to visit and have a nice discussion about the subject.
You can see and hear our Quad ESL-63 work and how that performs. PM me.
I think I've seen what you're asking about, but I can't find it at the moment. It seems like a reasonable compromise for your situation. It will probably change the lower midrange dispersion a bit, but I doubt it'll be a big difference in practice. If you want to test the idea before committing to the full modification, you could take the top panel out and temporarily mount it to the side or under the base while raising the rest of the speaker up.
There is this one, which moves the rings up, but also adds bass panels.
http://www.integracoustics.com/MUG/MUG/tweaks/quad/hey_you/stacking.html
There is this one, which moves the rings up, but also adds bass panels.
http://www.integracoustics.com/MUG/MUG/tweaks/quad/hey_you/stacking.html
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Hi Mattstat,
I indeed came across some reporting in this "tweak" before myself as well but can't find it back either... Nevertheless I like you pragmatic approach to evaluate the performance with the mi-high panels on top. Thanks!
I indeed came across some reporting in this "tweak" before myself as well but can't find it back either... Nevertheless I like you pragmatic approach to evaluate the performance with the mi-high panels on top. Thanks!
Hi Wout,
I think I know about your "Plus" work on Quads. Looks very nice. I get your point on d'Appolito configuration although I think reality is somewhat different. The radiation pattern from bottom panel is already quit different than the one from the top panel due to differences boundary conditions. I fully agree whith you that, to some extent, the part matching will be critical.
To come back to my initial question; If my assumption is correct, you guys must have rebuild numerous Quad ESL's? Did you actually ever try what I suggested?
Thanks!
I would be a much shorter list what we did NOT try and are still experimenting and testing every day.
That's why I invite you over for a chat as enthusiasts and have a listen.
One of the mayor reasons we think your approach is not a good idea is because there is special formed bass sections on the two middle panels.
It is not just like changing driver positions. Way too simple thinking IMHO, sorry.
If a certain speaker is praised for good performance and it doesn't in your conditions, think about the article Peter Walker wrote "The sound of the room".
Maybe your circumstances are much different from most, that forces changes (room wise). I see no real arguments in changing speaker wise.
There are no free lunches in audio, there is never a perfect solution, it is always pros and cons.
So also the chosen setup is a compromise, but a very well balanced one after much research.
I'd go for room treatment instead of the route of changing initial design choices.
That's why I invite you over for a chat as enthusiasts and have a listen.
One of the mayor reasons we think your approach is not a good idea is because there is special formed bass sections on the two middle panels.
It is not just like changing driver positions. Way too simple thinking IMHO, sorry.
If a certain speaker is praised for good performance and it doesn't in your conditions, think about the article Peter Walker wrote "The sound of the room".
Maybe your circumstances are much different from most, that forces changes (room wise). I see no real arguments in changing speaker wise.
There are no free lunches in audio, there is never a perfect solution, it is always pros and cons.
So also the chosen setup is a compromise, but a very well balanced one after much research.
I'd go for room treatment instead of the route of changing initial design choices.
ALL panels and all segments is reproducing low frequencies. So the whole speaker radiates like one single membrane and it starts from 30 Hz and up to 300Hz where the filtering starts to kick in but the bass panels plays up to 1kHz. You can easy sheck this with a microphone.
Did you try to turn and tilt the ESL backwards, making the surface of the smallest ring in the middle being perpendicular to your eyes from your listening position as well in the horizontal plane as in the vertical plane ?
Hans
Dear Hans,
Tilting them backwards helps but not is not enough for my taste. I still have the so-called "balcony listening experience... Thanks for the suggestion.
Michel
Tilting them backwards helps but not is not enough for my taste. I still have the so-called "balcony listening experience... Thanks for the suggestion.
Michel
I understand the working principle of the quads. Are ears/brain are able to pick up a sense of height from frequencies starting at +/- 300Hz and we get more sensitive to height location of an audio source when you move up in frequency. That nicely lines up with your statement on the cutoff points. That means that most of the height information is coming from the 2 full range panels in the middle of the stack. Hence my curiosity to shift them on top...
I have place a dipole sub below the QUADs.. but i agree with you 100% that if i would have them on the floor i would shift up the center panels to get the sphere in the height of my ears.
Hi, if nothing else works one could try HRTF equalization. Apparently humans are very bad at detecting height, other than from some variation in frequency response. See this https://www.nature.com/articles/s41598-018-37537-z
Perhaps your system has unfortunate frequency response, which makes your brain perceive it from below? If it is this, you might be able to tune this just with adjusting toe-in. Or, perhaps try with some simple EQ.
As others mentioned, tilt ought to help, tilt enough to reduce early refelction from floor and increase early reflection from ceiling.
Have fun!🙂
Perhaps your system has unfortunate frequency response, which makes your brain perceive it from below? If it is this, you might be able to tune this just with adjusting toe-in. Or, perhaps try with some simple EQ.
As others mentioned, tilt ought to help, tilt enough to reduce early refelction from floor and increase early reflection from ceiling.
Have fun!🙂
You should adhere to an equal triangle setup in your listening area and this would pull your speakers
away and up where they should be
Quads will always benefit from getting them off the floor. Tilting is a compromise
and will not produce a maximized soundstage they are capable of
A layout of your room would help
away and up where they should be
Quads will always benefit from getting them off the floor. Tilting is a compromise
and will not produce a maximized soundstage they are capable of
A layout of your room would help
Back in April of 2018 I did exactly what you are proposing. I put the two mid panels in the top two positions and the bass panels in the bottom two positions. I did a bunch of testing to see if the higher mid panels caused any pressure feedback around the top of the speaker at midrange wavelengths. I put a panel sized board on top of the speaker with the high mid panels to block the pressure feedback and took measurements before and after. I don't have nearly good enough notes on everything I did to convince myself this was a viable panel ordering but It did sound fine to my ears and did exactly what you are trying to do.
If I were to try this again I'd take some more detailed measurements and really show the changes in response, as it stands I've only got about 60% of the story.
With this pair was was also playing with 3M VHB adhesive transfer tape in place of my usual diaphragm adhesive. The VHB tape doesn't stick well enough to the stators to be viable in my testing.
Here are some ungated measurements of speaker response. I use these to assess my panel rebuild performance and also to verify proper electronics function. There is room response buried in these plots so don't read too much into them. They are only a tool for QA'ing my work, not a definitive response measurement
Here's the speakers with the normal panel order:
I then took a response shot of the re-arranged panels (sadly I'm not sure if I raised my mic or lowered the speakers. From the looks of it, I raised the microphone as evidenced by the dip at about 350 hz, which would indicate that I'm now closer to the midline of the room from floor to ceiling.
Here's what it looks like with and without my blocker board:
I was expecting much larger changes than what I saw. It makes sense, at low frequencies where pressure feedback is happening, the entire surface of the mid panels is active.
I'd suggest that if you are willing to go through the effort it's worth trying.
Sheldon
If I were to try this again I'd take some more detailed measurements and really show the changes in response, as it stands I've only got about 60% of the story.
With this pair was was also playing with 3M VHB adhesive transfer tape in place of my usual diaphragm adhesive. The VHB tape doesn't stick well enough to the stators to be viable in my testing.
Here are some ungated measurements of speaker response. I use these to assess my panel rebuild performance and also to verify proper electronics function. There is room response buried in these plots so don't read too much into them. They are only a tool for QA'ing my work, not a definitive response measurement
Here's the speakers with the normal panel order:
I then took a response shot of the re-arranged panels (sadly I'm not sure if I raised my mic or lowered the speakers. From the looks of it, I raised the microphone as evidenced by the dip at about 350 hz, which would indicate that I'm now closer to the midline of the room from floor to ceiling.
Here's what it looks like with and without my blocker board:
I was expecting much larger changes than what I saw. It makes sense, at low frequencies where pressure feedback is happening, the entire surface of the mid panels is active.
I'd suggest that if you are willing to go through the effort it's worth trying.
Sheldon
I'm not sure that's a big player in a dipole like this where there isn't a lot of energy way off axis.
Sheldon
Hi, great to get feedback from someone who actually tried it!
About your measurements;
As long as you keep the mic at position (😁) and you tilt the speakers in a way that the mic remains on-axis with the center of the high freq section, for both the original and the alternative panel sequence, I don't expect big changes in the spectral balance (aside from a shifted cancelling effect from the floor).
What was/is your experience with the elevation of the stereo image?
Many thanks for sharing your experience and detailed measurements!
Michel
WRT the measurements. I took woefully inadequate notes, so I don't have a good feel for if I changed the mic position. It appears that I used two different height stands and kept the mic constant. But I also suspect that my position accuracy from one speaker to the other could have been better. I can tell distance from the impulse delay, but not height.
The image got higher, just as you would expect. The stand and deliver stands elevate the speakers a bit and my goal here was to get the acoustic advantage of the stands without the ugliness of a pair of hovering speakers. Arcici stands elevate the speaker even higher, so a simple panel swap doesn't quite get you there. But the Arcici stands are also ***-ugly and damage your speaker frames and grille cloth.
Sheldon
The image got higher, just as you would expect. The stand and deliver stands elevate the speakers a bit and my goal here was to get the acoustic advantage of the stands without the ugliness of a pair of hovering speakers. Arcici stands elevate the speaker even higher, so a simple panel swap doesn't quite get you there. But the Arcici stands are also ***-ugly and damage your speaker frames and grille cloth.
Sheldon
Hi, I basically lived on the thick-wool-carpeted floor with ESL63 on factory stands, for several years right after graduation. So that was fine. Then nomadic life began and I switched to Monitor Audio Studio (nearly as coherent) and then fullrange drivers. If anyone has fullrange or other "coherent" speakers I would suggest as an experiment to lay one or both down flat to fire upward "omni"; soundstage should then float midair above and beyond the speakers (I described several in the fullrange photo gallery). With dipole panels this would be tricky to do or conceptually weird, but one might try listening while lying on the floor....