The Logos panel has a advantage and disadvantage ad the same time, The panel is curved and that courses that under bending the mylar comes very close to the back stator ,on the other side you can pushed the panel to a flat panel ,that is important because now you can put the mylar under tension on the stator.
Because I change the filtering for the Logos in a 2 way filtering I use the whole panel without tweeter . (if you will keeping your tweeter in the middle you can cut out the mylar in the middle) .
The spacers I used are for the back stator 2.0 mm thick and for the front 1.5 mm . I have tried to used thinner ones but that resulting in noises and sparkles because the mylar is too close to the backstator ,almost against.
So you need double sided adhesive tape from 3M (VHB tape) with a thickness 1,5 mm and 2.0 mm and 12 mm and 6 mm wide. (online shop UK; www.williamhayes.co.uk[url] also o...hickness . [url]www.freeflightsupplies.co.uk/
It is not always easy to get the tape on the right thickness , I use 3M RP62 foamtape which is 1.5 mm thick (william hayes) and on that VHB acrylaattape from 0.6 mm thick (
www.van-Asperen.nl) total 2.1 mm (practical 2.0 mm)6mm wide.
6mm wide clear tape /1.5mm thick also from 3M 4915F (william hayes)
Coppertape 3M with conductive adhesive 6mm wide (
www.conrad.de or conrad.nl)
You must work on a flat surface table .
We begin with the tape on a clean ,undamaged back stator ,
Around the stator we use the 12 mm/2.0 VHB tape (leave the protective plastic on the outside on his place) , we make 4 strips in the left/right part of the panel and 5 strips in the middle. For making these stripes we use the 6 mm/2.0 tape .Don't forgot the 2 vertical lines in the middle ,you can use here the 6 mm tape (if you cut out the middle for the tweeter then use 12mm tape here.). Alongside the 12mm tape you put 10mm isolation tape .Be sure that the surface where you put the tape is clean .I make the follow partitions ; left/right part of the panel; strokes 40/50/50/40 (4 strokes approx in mm).In the middle 5 equal strokes .
In mine case I have mount the membrane wire (the red one ) soldered on 2 short pieces of copper tape on the stator because I choose for hold the conductive (alu film) layer to the inside of the stator so that you can always make a conductive layer on the outside of the mylar by your self if you don't like the alu film layer . If you trusted the alu film layer it is easier to mount the wire after you put the stator on the mylar.
At least put at the end of the stator, through the holes ,on both ends a thin iron wire where you can hold the stator on .
If this is ready we start with the mylar . You must work on a flat clean surface from at least 1.50 m (5 ft) by ap 2 ft . Important ; it depends of how you make the wire connection how you put down the mylar ,it is only conductive at one site ! And that is the site that shins like a mirror. I had the conductive alu layer up but you have then made the copper/wire on the stator if you choose for the easier way you have to put the alu conductive layer down. You stick the mylar on the surface with thin wide tape normal used to wrapped parcels . You started in the middle , stick the tape approx 25 mm on the mylar .Look at the picture below . I stretched the mylar to 34 mm wide(is unstretched 30mm) . Stretch the mylar more on the short site not over the long site , only if needed to remove wrinkles. Bit for bit you stretch the mylar to 34 mm equal over the total length .
If the mylar is stretched well without any wrinkles en clean the mylar as a mirror and remove dirt and grease so that the tape is holding under tension. You have to lay down now the stator on the mylar ,remove the protection of the tape carefully and lay down the stator on the mylar ,you can hold the stator through the iron wires you putted on.,it is very important not to move the stator after touching the mylar so I have made a small wooden board to guide the stator . Put down the stator till it is flat on the mylar and put some weight on it to prevent that the stator is coming up. I used heavy flat tiles with buckets filled with water . Leave it there for at least 12 hours so that the tape can become stronger to hold the mylar on its place . So the next day is an exiting one to see of it works well . Losing the tape which the mylar is fitted on the surface equally over the whole membrane , turn the stator and then you can see of there is indeed tension on the mylar. Check if the red wire make connection with the mylar with a universal ohm meter. Go with a roller over the mylar/tape so that the tape is holding good on the mylar. Then cut the mylar approx 5mm from the edge of the tape . To avoid invert between membrane and stator you bend the mylar to the inner side over the tape ,use double sided thin (photo) tape and keep away the mylar from the stator, you cannot avoid wrinkles but that doesn't matter . Put then isolation tape around the edges of the membrane. If you want to use the original tweeter in the middle of the panel you have to cut out the mylar where the tweeter comes ,leave the upper en down site of the membrane ,use a very sharp knife.( in this case you have to use 12mm wide tape on the vertical strokes)
So …...If it is alright you have done the most difficult part of the work, now you only have to place the spacer tape on the other stator .Use around the stator 12mm wide,1.5 mm thick tape , I use for the right /left part only 1 spacer tape 6 mm wide and for the middle 2 rows and of course the vertical ones. Do not remove the protection layer on the tape ! I hold the 2 stators together with plastic clams (see photo , wire gutter,the one normally used to guide lamp wires) all over the long site from the panel ,it works very well and you can always remove this stator to clean or change your panel.
Now the most exiting ….does it work , go for it and listen …...
I tell you the 2 attempts I made before it works ;
The first time I used 0.04 micro clear mylar and coated it with thin layer of grafit spray , I used the spay 2 times before it works. I made 3 part ions and a tape thickness for the front ; 1.5 mm/back 0.65 mm (advise from Scott) It sounded oke but there was a lot of noise and spetters if I bend the panel to fit the cabinet .It seems that the mylar was touching the stator .
The second time I raise the membrane tension and made 4 partitions (one small one from 30 mm) ,in the middle section 3 partitions ,use metalized mylar 0.1 micron , same space between the stators.
The noise and hissers were less but not gone and there were sparkles between the front stator and membrane by higher volume so I raise the space between the front stator and membrane till 1,5 mm and the sparkles were gone but the hisses and noise were not when bending the panel completely to fit . The overall sound was very good .
The thirth time I increase the space between the back stator /membrane till 2.1 mm (put 0.6 mm on 1.5 mm tape) ,make 4 partition/strokes in more or less equal ways and in the middle where the bending is the biggest , 5 strokes and stretcher the mylar more in the short direction then in the length .And now …................... marvelous !
View attachment 15951
where I put a new membrame .It is not difficult ,takes some time but you don't need special tools only the right mylar and tape . Let me know of you are interested and I shall tell what parts you need and where to buy it and how to do it .
