At the risk of being laughed off this forum,I would like to share some thoughts on the Eikona 2 and the VTL. I have had my Eikonas for about 6 months, and have tried various enclosures, but have not been happy with any of them. I decided to try the VTL from the Jordan website, though my version was 30mm shorter due to height restrictions. I was impressed with the bass extension, but not with the nasty resonance around 150Hz triggered by male voices and the lower string instruments. I spent 3 months experimenting with damping materials in various configurations, but was unable to eliminate it. About to give up on it, I remembered something I came up with over 60 years ago..Corrugated paper tightly rolled into a cylinder forms dozens of parallel tubes which allow sound to travel through it, acting as a kind of waveguide. If fitted into a transmission line, sound from the rear of the speaker will be conducted to the exit unable to bounce off any interior surfaces. If the path is long enough, the higher frequencies will be lost. I modified my VTLs in this way, cutting the tube at 45 degrees where sections intersect to form a sort of U bend. I can now listen to Shostakovich without the annoying colouration.I'm sure this system can be used in other enclosure designs with advantage.
Hi Sheiron - The VTL is designed to be used as specified on the plans and we have many happy constructors. The VTL is a coupled cavity TL, a design principle Ted had worked with regularly from the late 1960s onwards. It shouldn't require the cardboard filter. If it did, Ted would have designed it in (he patented a design of aperiodic enclosure whilst at Goodmans in the late 1950s.)
I think Proac did something similar with their speakers, many years ago, stuffing the reflex ports with drinking straws.
When you say you reduced the height, I assume that this only refers to the stand rather than any part of the enclosure itself? Have you tried modifying the wadding used in the cavity behind the Eikona? And can you confirm that it isn't a room effect?
I think Proac did something similar with their speakers, many years ago, stuffing the reflex ports with drinking straws.
When you say you reduced the height, I assume that this only refers to the stand rather than any part of the enclosure itself? Have you tried modifying the wadding used in the cavity behind the Eikona? And can you confirm that it isn't a room effect?
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Hi, Scottjoplin, I first tried them in the enclosures which I had used for the JX92, a sealed box. I also tried a discarded sub-woofer cabinet, and other enclosures that I have accumulated. I have not tried any enclosure designed for the Eikona apart from the VTL which I had to slightly modify.
I have Eikona VTL and had a problem with a peak, I'm guessing around 200Hz, this was cured by placing them flat against the front wall (the ideal position for them?) and farther away from the corners, it was a room reflection. How do you have yours placed? BTW, I'm a big Shostakovich fan
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Hi Scottjoplin, Interesting that you noticed a peak, I wonder if yours was cured, or "cancelled out" by moving the enclosures - just a suggestion. My resonance stayed wherever I put the boxes....even flat on their backs on the carpet. Again, after fitting the paper rolls, I can put them anywhere without a problem
Jordan Eikona 2 VTL
Hi Colin, I want to make it clear that my post was not in any way, a criticism of Ted's design. I had the pleasure of meeting him way back in the 'sixties. and spoke to him on the 'phone subsequently. I have used his speakers over the years, starting with the Jordan Watts module, the JX92, and now the Eikona. I mentioned in my post that I had reduced the height of the VTL by 30mm.- the enclosure itself. I accept that this may have contributed to the resonance. Yes I did try variations of the padding behind the speaker, including doubling the thickness, as the magnet was not in contact with it as shown in the diagram. For this reason also, I added "front to back" braces close to the speaker. With regard to " room effect" I can only say that the boxes are in the same position as they were....nothing has changed except for the addition of the paper tubes, which in my case were a great improvement. Thank you for your interest.
Hi Colin, I want to make it clear that my post was not in any way, a criticism of Ted's design. I had the pleasure of meeting him way back in the 'sixties. and spoke to him on the 'phone subsequently. I have used his speakers over the years, starting with the Jordan Watts module, the JX92, and now the Eikona. I mentioned in my post that I had reduced the height of the VTL by 30mm.- the enclosure itself. I accept that this may have contributed to the resonance. Yes I did try variations of the padding behind the speaker, including doubling the thickness, as the magnet was not in contact with it as shown in the diagram. For this reason also, I added "front to back" braces close to the speaker. With regard to " room effect" I can only say that the boxes are in the same position as they were....nothing has changed except for the addition of the paper tubes, which in my case were a great improvement. Thank you for your interest.
Obviously we can't guarantee the performance unless you follow the plans closely. Ted said to me once that these types of enclosure don't always behave the way you expect. It was developed over several versions, initially for Konus and then as the VTL design for DIY use.
If the tubes work, that's fine, you're damping the port. My feeling is that cavity damping would work better but if you have already tried it and this solution works for you in your room, go with that
If the tubes work, that's fine, you're damping the port. My feeling is that cavity damping would work better but if you have already tried it and this solution works for you in your room, go with that
I remember trying something I read about on a forum about 15yrs ago - to tame resonances in what looked like a Helmholtz trap in a goofy BLH design; - rolled up single face corrugated cardboard stuffed in the chamber. There were so many other issues with the design that I can't remember if / how much effect that had.
Yes, it can. You can mount it in the same was as the DCR shown on the blog
Project - Classical Jordan DCR - E J Jordan Designs
Project - Classical Jordan DCR - E J Jordan Designs
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