ESS AMT foil damaged

dieringe

Member
2002-03-31 11:59 am
I have an older pair of ess air motion tranformers.
While trying to put them into a case, I pulled the wire a bit too hard, so that the foil is now broken near the connectors at 2 points.
Does anybody know how I could possibly mend this? Soldering is not possible. Is there anything you can use to connect aluminum foil (or whatever it is)?

If it is not possible, maybe somebody knows if there are replacement foils for these (old) speakers available? they are from the "Performance Series 5". The foil itself is about 33x75mm.
 

dieringe

Member
2002-03-31 11:59 am
WIRING?

:confused: :headbash:

anybody knows how they're wired?
I found means to reconnect the strips, but end with either zero ohms or no connection.
I once had a little bit of sound, but very weak
and don't remember how I did it

# | | | | | | | | |----------wire1
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |
# | | | | | | | | |----------wire2

^
|
broad strip

where are there connections between strips?

wire1 and wire2 can't possibly be connected to the same strip! but the other (working) one looks like this. is there an isolation between 2 strips?
I can't see anything else I can connect the lower
wire to

are all visible strips really 2 layers isolated from each other?

I thought the current should have the same direction on all strips?

please somebody explain this to me
 
I'd start with the Patents:

<a href="http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1='3636278'.WKU.&OS=PN/3636278&RS=PN/3636278">US Patent 3,636,278: ACOUSTIC TRANSDUCER WITH A DIAPHRAGM FORMING A PLURALITY OF ADJACENT NARROW AIR SPACES OPEN ONLY AT ONE SIDE WITH THE OPEN SIDES OF ADJACENT AIR SPACES ALTERNATINGLY FACING IN OPPOSITE DIRECTIONS</a> Heil, Oskar <hr width="95%" align=center><a href="http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1='3832499'.WKU.&OS=PN/3832499&RS=PN/3832499">US Patent 3,832,499: ELECTRO-ACOUSTIC TRANSDUCER</a> Heil, Oskar <hr width="95%" align=center>

You will need a tif viewer like <a href="http://www.alternatiff.com/">Alternatif</a>

Also have a look at <a href="http://layneaudio.hypermart.net/prod03.htm">Layne Audio: Speaker Parts and Repair</a> Scrool Down to ESS.

Hope this helps

Regards
James
 
The European distributor is Audio International in Frankfurt. They don't have a web page, but the phone number is in most issues of HobbyHifi or Klang und Ton. I believe it is 069/503570.

Hifisound in Münster also carry AMT as well as replacement diaphraghms. Their link is www.hifisound.de.

What kind of project are you working on? Is it the small or the large AMT?

Greetings,

Eric
 

dieringe

Member
2002-03-31 11:59 am
thanks

...for the answers.

i give up repairing them and will order the replacement foil from Achenbach in Friesenheim. it's 90 euros, but probably worth it.

this are old speakers from the Performance Series. I only have the 2 speakers and have yet to find a project to use them.
does anybody know something simple?
(I have never built speakers before, only electronics)
 

lieven

Member
2002-08-11 4:42 pm
Belgium
if you know the high-cut-off frequency of the lower band speaker (traceable with freq-sweep from cd, pc or freq-generator + micro and pc-software or freq-analyzer), apply cut-off frequency to both speakers (!!! both connected via x-over!!!) holding micro in the middle between both speakers.
Connection with loudest signal is the right way.
Otherwise they are phase-opposed and will cancel each other.

X-over insertion is important because x-over may turn phase 180 degrees (changing + to - or red to black)
 
Projects

Well, there is the AMT-V and AMT-V active project from Klang und Ton but looking at the impulse response, these designs muck up the excellent temperoral performance that can be achieved with the AMT.

I just visited Audio International in Frankfurt and listened to their I.2 speakers. These are a smaller version of the time-corrected I.3 speakers that were tested in the current issue of Hobby Hifi.

The sound is increadibly transparent. On the other hand, it jumps at you and I can imagine it will be too aggressive in the long run. I also listened to a smaller design by them with the AMT2. It was not as spectacular but, being more laid back, might also have its virtues.

Anyway, the I.2 should be pretty easy to make, it consisting mainly of a bass reflex box that holds two 17 cm Excel magnesium membrane woofers. The AMT 1 simply sits on top. The woofers are a special version made exclusively for Audio International. I think they are 230 Euros each, so if you already have the AMTs, you should figure about 1300 for four woofers, the wood and the XO.

Eric
 

dieringe

Member
2002-03-31 11:59 am
the Hobby Hifi version is just too complicated and
too expensive for me.

I'd like to make a box for the AMTs, no volume,
just to close them in the back.
then make an extra box with a single bass driver, up to 1500-2000Hz, probably reflex.
is this a good idea? has this been done before?
 
I was thinking the same.
It´s too expensive and too complicated. 3 more drivers and a crossover for a three way is too much.
Why do you want to close the tweeter is there a reason for that?
I will probably make an extra box with two peerless HDS205 woofers in each. They can go up to 1500. I will put them in a separate bass reflex enclosurewith a horn type tube, I have read they are better than the streight ones.
The peerless woofers are 91dB and have very flat response so the crossover will be very simpleand the end sensitiviy will be around 95- 96 I hope but at 4 Ohm.
 
dieringe said:
the Hobby Hifi version is just too complicated and
too expensive for me.

I'd like to make a box for the AMTs, no volume,
just to close them in the back.
then make an extra box with a single bass driver, up to 1500-2000Hz, probably reflex.
is this a good idea? has this been done before?

Well, the I.2 is almost that. It has two woofers, i.e. a little more complicated. On the other hand, the AMT1 just sits on top with no case at all, i.e. acting as a dipole radiator.

Eric
 

dieringe

Member
2002-03-31 11:59 am
promitheus said:

Why do you want to close the tweeter is there a reason for that?
I will probably make an extra box with two peerless HDS205 woofers in each.

I have to close them because they are different. Its an older version.

Why two woofers? For sensitivity?
If I dont need sensitivity, I could as well use
one woofer and put a resistor before the tweeter - right?
 

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dieringe

Member
2002-03-31 11:59 am
THE FOIL

yeah theres only two, but whats in between?
which way is the current going?
I couldnt find out with a multimeter.

resistance violet cable to opposite (top) side is 2.5ohms (half resistance). very good.

blue cable to violet is zero or infinite depending on whether I connect the blue to the next strip (lower left end) or not.

the connections come up at the edge but seem to be connected to the SAME strip (can't be true)

at the red dot I made the cut, because this strip SEEMED to go through, but didn't (two layers!).

nelson, please, ask your wife! :smirk:


every foil fold has two aluminum strips inside.

here is a scan of the foil after HOURS of maltreating:
 

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