I do this frist thing when I pull the box.........if you can
I use hot glue....what ever you uses.... put in the paper gaps.... were the wires exit the tran......When the hot glue drys...the wire well be held tite........... here 2 ML tran.....I can get the hotglue in side the paper...an drys... now...........in the pic
.
before you move any wires....or even cut the zips....
I have old bass tran ...that just was removed..DOA..hart brak.... now that papers so dry .....the wire can move an break ...an you can kill the tran....
jestsaying....thanks Andy
I use hot glue....what ever you uses.... put in the paper gaps.... were the wires exit the tran......When the hot glue drys...the wire well be held tite........... here 2 ML tran.....I can get the hotglue in side the paper...an drys... now...........in the pic
.
before you move any wires....or even cut the zips....
I have old bass tran ...that just was removed..DOA..hart brak.... now that papers so dry .....the wire can move an break ...an you can kill the tran....
jestsaying....thanks Andy
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I'd double check all interconnect cables on that channel, reversing and straight, could be a poor ground. I had this happen a couple a times, can drive you nuts, other thing I would check is the ground wire connection in the wall recepticle, plug and interface. make sure you have a solid ground.
If the amp was just turned on, but no music was playing then the voltage difference between blue and yellow wires should be essentially zero; both at safety ground potential, right? or am I missing something.
The attached pic shows some tubing slipped over the blue and yellow wires…was this the factory build method you were describing?
When you turned on the amp power, were you inputting any audio to it?
Also, what type of amp is it? Does it use a safety ground?
Attachments
Yes, that looks like the factory-applied PVC tubing. At some point, but possibly not at the same time, Acoustat began sheathing the wires that ran up into the panels to reduce corona effects. If memory serves correctly, at the very least, all Spectras were build this way, with the front and rear stator wires bundled separately and covered with PVC tubing. I even developed a custom-made tool for grabbing the end of the wires to pull them through the tubing. Not an easy job, especially on the double-stacked models Spectra 44/4400 and 66/6600.
If there was no signal applied to the amplifier when you turned it on, and you observed an arc on the largest transformer, there is something very wrong in your system. With no signal applied to the interface, there should be no high voltage to create an arc, no matter how bad or damaged the insulation may be.
Therefore, I am back to suspecting that your amplifier is oscillating into the speaker load, which is, in effect, an input signal creating high voltage, which is then arcing. It is probably a very large signal that is causing a breakdown of the insulation. I suggest you try a different brand of amplifier to determine if you have a compatibility problem. I have no familiarity with your Cinepro brand.
In regards to the PVC tubing, this is a generic item. Try Digikey or Mouser, both are on-line electronics distributors.
Or ....Or Go to a pet store an get fish tank air pump tubing....... An lowes has
some
.....that's a ezey fix................
But sounds like your amp .....don't like what it sees
......it not the frist amp that....has turned an run away from panles, ESLs type speakers.....But it to bad..
These old Acoustats can sound great.
I wish some time in the past 30 years ....a pr of these Acoustats would have not worket...... are something....every time I tried to get away from them...
I get a pr for almost nothing $$ wise.....an thay play just good a nuf....to drag me right back again.....
Poor Me....Hehe.. Someof the best sound I have ever had....me in my room.............Justsaying
.Good luck
some
.....that's a ezey fix................
But sounds like your amp .....don't like what it sees
......it not the frist amp that....has turned an run away from panles, ESLs type speakers.....But it to bad..
These old Acoustats can sound great.
I wish some time in the past 30 years ....a pr of these Acoustats would have not worket...... are something....every time I tried to get away from them...
I get a pr for almost nothing $$ wise.....an thay play just good a nuf....to drag me right back again.....
Poor Me....Hehe.. Someof the best sound I have ever had....me in my room.............Justsaying
.Good luck
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Aragon 4004 MKII have enough voltage for Acoustats?
Hi guys,
Reading through the thread now but wanted to see if anyone knows if my Aragon should do ok with 1+1's? I used to run 2+2's off it and never had any issues. I did notice slapping sometimes when I was pushing them kinda hard.
Wanted to know if anyone knows the voltage it is capable of.
Thanks!
Hi guys,
Reading through the thread now but wanted to see if anyone knows if my Aragon should do ok with 1+1's? I used to run 2+2's off it and never had any issues. I did notice slapping sometimes when I was pushing them kinda hard.
Wanted to know if anyone knows the voltage it is capable of.
Thanks!
An amplifier suitable for the 2+2 should also be suitable for the 1+1. However, keep in mind that the 1+1 will not play as loud, and will not have the same bass extension. Therefore, you will experience 'slapping' sooner than you would with the 2+2.
FYI - the 'slapping' is merely the diaphragm reaching its excursion limit, and doesn't do any real harm to the panel. However, this is an indication that you are driving the speaker at or near its limit, so caution is advised so as not to cause any damage to the audio transformers. In some cases you might be able to reduce the slapping by re-shrinking the diaphragm, but even for a 1+1 in 'perfect' condition, you will still experience this effect at some point.
I can't answer your question about the voltage output of your amplifier, but I think the above answers are more pertinent to your situation.
Hello Everyone,
Andy, thank you so much for starting this thread and offering your advice and knowledge to others, this is a fantastic resource for Acoustat owners!
I originally purchased a pair of model 2 speakers in 1979 and have enjoyed listening to them since then. When they were brand new, I had a problem with one of the panels making buzzing noises once the speaker was fully charged up. A close examination of the panel revealed that a bit of melted plastic had dripped down from where the wires were attached to the plastic frames in manufacturing. This obviously occurred when the panel was laying flat and not vertical as they are mounted in the speaker frame. I was able to break off the plastic bit that was causing the problem, fixing the panel and allowing me to enjoy the speakers instead of returning them to Acoustat for repairs.
A few years back I purchased a pair of 1+1s so that I could use them (with the better medallion transformers) as my main speakers and then rebuild the older model 2s into single panel rear surround speakers and possible a center channel speaker as well. Unfortunately, one of the panels on these newer speakers also had a buzzing vibration when fully charged. I spent many hours unsuccessfully trying to find loose wires, cracked frames, or plastic bits like on my original panel causing the issue. I retensioned the panel as well to no avail. Eventually I gave up and opened the panel up, finding another plastic drip just like the one on my original speakers. Unfortunately, it was completely invisible from the outside, and the panel was now non-functional even though I had found the root cause of the buzzing. I ended up putting my original model 2 panels into the 1+1 frames and have been using them that way ever since. I have yet to try setting up a one panel speaker for my rear surrounds.
The original owner of the 1+1s, who had purchased them new, had never had any problem with the speakers and became very upset, thinking that I was trying to scam a refund. I don't know if the problem only came to light because they were originally in a higher humidity environment, or if my AC power was at a slightly higher voltage causing higher bias voltage and more panel excursion, or if it was some other reason. I can say that if anyone is experiencing similar buzzing problems that this can be a cause as well as the usual loose wires that people have found. Certainly if I have encountered it in two different speakers manufactured a number of years apart, that it must be happening in other speakers as well.
Over the years I have had voltage multiplier capacitors fail, causing a partial loss of bias voltage and sound output, and one time one of the big resistors on the output of the bass transformer failed as well. Overall though, considering the years of use they have had, I consider them to be very reliable. Hopefully other people can benefit from my experiences here as well. Andy, did you ever encounter anything like this in the factory?
Take care,
Doug
Andy, thank you so much for starting this thread and offering your advice and knowledge to others, this is a fantastic resource for Acoustat owners!
I originally purchased a pair of model 2 speakers in 1979 and have enjoyed listening to them since then. When they were brand new, I had a problem with one of the panels making buzzing noises once the speaker was fully charged up. A close examination of the panel revealed that a bit of melted plastic had dripped down from where the wires were attached to the plastic frames in manufacturing. This obviously occurred when the panel was laying flat and not vertical as they are mounted in the speaker frame. I was able to break off the plastic bit that was causing the problem, fixing the panel and allowing me to enjoy the speakers instead of returning them to Acoustat for repairs.
A few years back I purchased a pair of 1+1s so that I could use them (with the better medallion transformers) as my main speakers and then rebuild the older model 2s into single panel rear surround speakers and possible a center channel speaker as well. Unfortunately, one of the panels on these newer speakers also had a buzzing vibration when fully charged. I spent many hours unsuccessfully trying to find loose wires, cracked frames, or plastic bits like on my original panel causing the issue. I retensioned the panel as well to no avail. Eventually I gave up and opened the panel up, finding another plastic drip just like the one on my original speakers. Unfortunately, it was completely invisible from the outside, and the panel was now non-functional even though I had found the root cause of the buzzing. I ended up putting my original model 2 panels into the 1+1 frames and have been using them that way ever since. I have yet to try setting up a one panel speaker for my rear surrounds.
The original owner of the 1+1s, who had purchased them new, had never had any problem with the speakers and became very upset, thinking that I was trying to scam a refund. I don't know if the problem only came to light because they were originally in a higher humidity environment, or if my AC power was at a slightly higher voltage causing higher bias voltage and more panel excursion, or if it was some other reason. I can say that if anyone is experiencing similar buzzing problems that this can be a cause as well as the usual loose wires that people have found. Certainly if I have encountered it in two different speakers manufactured a number of years apart, that it must be happening in other speakers as well.
Over the years I have had voltage multiplier capacitors fail, causing a partial loss of bias voltage and sound output, and one time one of the big resistors on the output of the bass transformer failed as well. Overall though, considering the years of use they have had, I consider them to be very reliable. Hopefully other people can benefit from my experiences here as well. Andy, did you ever encounter anything like this in the factory?
Take care,
Doug
All sorts of foreign matter can get stuck inside the gap between the stators and the diaphragm. Bits of plastic or glue from the panel itself, dead bugs, hair, etc. can all cause buzzing, rattling etc. And, if the foreign object is even slightly conductive (like bugs or hair), it can also cause localized leakage, which usually manifests itself as a sizzling, hissing or ticking sound.
At the factory, panels were routinely blown out with compressed air to remove debris, but the process was obviously not always 100% effective. And of course, over time, bits of plastic or glue can work loose and cause trouble. These problems often show up after the speaker is moved or handled. A thorough vacuuming of both sides of the panel is always a good idea whenever there is a problem or the grille cloth is removed for any reason. This needs to be done with the speakers completely discharged so as to remove any electrostatic holding force that might be exerted on the foreign matter. I make it a habit to vacuum the outside of the grille cloth on my speakers every few months, just to reduce the accumulation of dust that might work its way into the interior of the speaker. And it doesn't hurt the appearance of the speaker, either!
Other than some periodic cleaning of dust and debris, Acoustat panels are incredibly reliable compared to virtually any type of speaker, and particularly compared to other brands of ESL's.
In both of the panels that I had this issue it could be clearly seen that the plastic bits were actual drips of plastic/glue from the manufacturing process. They were both still firmly attached to the panel where the stator wires were glued on and had to be broken off to be removed. Blowing out the panels with compressed air would not have affected these at all, and it was obvious that they had been there right from the beginning when the panels were first assembled.
I completely agree with you about the reliability of Acoustats, they are an amazing design. It really is a shame that they are no longer being produced.
Take care,
Doug
this is some info I found on the web................
here my qus...........if the Acoustat coting was Ampex tape coating....would not any other tape coating work?
I never new the coating was made for Ampex magnetic tape
but for sure the 500mg res .....in the bias in my setup has be dropet to 10-60mg to get better sound out of the panels....an one more diode an cap added
here more info.................in the pic...I like the reworked bias feed...hehe
Audio Asylum Thread Printer
Audio Asylum Thread Printer
Actually the coating used was never proprietary, but according to Andy (as I recall) it was only made available to Acoustat because of a connection with Ampex that either Jim or his partner( whose is now deceased, but was a nice guy). Apparently Ampex was not given to allowing the coating to be used by others. I am sure that to Ampex it was very proprietary as this was during the time when analog tape was the medium of choice and competition was fierce.
One thing that I think bears mentioning, the stators on the Acoustat's never see 5kv, at least when driven by servos, the max voltage is around 1700vac rms before the stock amplifier clips. I am sure that the voltage on stators is more often less than 700vac. It may be that with the interfaces the stators see higher voltage and why they play louder. We have been using a higher voltage HV power transformer with the resulting output of about another 250vac per side. The diaphragm sees a much lower voltage, around 120vac as I recall, since it is charged from the 5kv p/s through a 500meg resistor. The interface uses the same resistor value.
here my qus...........if the Acoustat coting was Ampex tape coating....would not any other tape coating work?
I never new the coating was made for Ampex magnetic tape
but for sure the 500mg res .....in the bias in my setup has be dropet to 10-60mg to get better sound out of the panels....an one more diode an cap added
here more info.................in the pic...I like the reworked bias feed...hehe
Audio Asylum Thread Printer
Audio Asylum Thread Printer
Actually the coating used was never proprietary, but according to Andy (as I recall) it was only made available to Acoustat because of a connection with Ampex that either Jim or his partner( whose is now deceased, but was a nice guy). Apparently Ampex was not given to allowing the coating to be used by others. I am sure that to Ampex it was very proprietary as this was during the time when analog tape was the medium of choice and competition was fierce.
One thing that I think bears mentioning, the stators on the Acoustat's never see 5kv, at least when driven by servos, the max voltage is around 1700vac rms before the stock amplifier clips. I am sure that the voltage on stators is more often less than 700vac. It may be that with the interfaces the stators see higher voltage and why they play louder. We have been using a higher voltage HV power transformer with the resulting output of about another 250vac per side. The diaphragm sees a much lower voltage, around 120vac as I recall, since it is charged from the 5kv p/s through a 500meg resistor. The interface uses the same resistor value.
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![Acoustat%20pics[1].jpg](/community/data/attachments/426/426886-cbd7e1615146187627eb14ab839c1bd5.jpg)
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Warm greetings from Portugal, Acoustatman,
I am missing the Yellow/red wire from acoustat spectra panel: is it possible to fix this? Looks like whoever removed the panel from the speaker cut all the 4 wires short (coming from the top of the panel) and must have pulled the yellow wire with the red stripe with such force that there is a sorry looking hole left there. What sort of wire can I use to fix this and how? The other 4 wires are shorter, so once I join a wire to each one of them, what sort of insulation should I use to cover the joint? I have no idea of the voltages that will be present on these wires, but the red/yellow wire will have at least 5 kV!
Any help will be appreciated, thanks,
Alnasir.
I am missing the Yellow/red wire from acoustat spectra panel: is it possible to fix this? Looks like whoever removed the panel from the speaker cut all the 4 wires short (coming from the top of the panel) and must have pulled the yellow wire with the red stripe with such force that there is a sorry looking hole left there. What sort of wire can I use to fix this and how? The other 4 wires are shorter, so once I join a wire to each one of them, what sort of insulation should I use to cover the joint? I have no idea of the voltages that will be present on these wires, but the red/yellow wire will have at least 5 kV!
Any help will be appreciated, thanks,
Alnasir.
Ouch, that is very bad. The yellow/red wire is the high voltage bias connection to the diaphragm. As constructed at the factory, the conductive coating was painted off the edge in one small area. The bare end of the bias wire was laid down on top of the coating, and adhered with metal foil tape. Then the two halves of the panel were sandwiched together. Glue was used at the point where the wire exited to strengthen the connection.
I'm really not sure how to fix this. Can you supply a photo of the place where the wire should be? Perhaps this will give me an idea how to approach this problem.
black hole
super help needed now I have just found a hole in one of the 2+2 acoustat panels its about the size of a grid square any options at all? finding a replacement panel in NZ is impossible can I just snip the wire and run 3 panels can anyone tell me how to take panels apart and is this difficult?
also after vacuuming warm air blowing staring, glaring ignoring yelling cursing and threatening the rubbish bin one of the other panels isnt working either any suggestions there?
super help needed now I have just found a hole in one of the 2+2 acoustat panels its about the size of a grid square any options at all? finding a replacement panel in NZ is impossible can I just snip the wire and run 3 panels can anyone tell me how to take panels apart and is this difficult?
also after vacuuming warm air blowing staring, glaring ignoring yelling cursing and threatening the rubbish bin one of the other panels isnt working either any suggestions there?