Is this the end of 70 or 100 volts systems?

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Hi cbdb,
Same as the Toronto area. Store owners normally get someone to install the speakers for next to free, and if you see 70V matching transformers, you're dealing with someone up on something. DJs did a lot of these installs too, but they never figured out that the big transformer was needed, or included in the paging amps.

Just a wide trail of smoking amplifiers and bar owners determined not to pay for their own problems. Lovely business.

This "invention" does zero to protect an amplifier as many have noted. I'd loccve to see those vent if installed in a 200 watt + system. :)

-Chris
 
This "invention" does zero to protect an amplifier as many have noted. I'd loccve to see those vent if installed in a 200 watt + system. :)

-Chris

It looks like the amp is a Lab Gruppen FP14000, capable of around 7KW/ch.


If that amp was turned up, it'd be able to exceed the DC rating of their installed capacitor. The problem doubles when you remember the main cap is polarised.
Capacitors don't like being reverse-charged, and tend to make their discomfort known in a big way.

Does anyone else feel this product is seriously unsafe?

Chris
 
How can long cable runs be used, when voltages are low and currents are very high? Furthermore, individual speaker power adapting isn't possible anymore and thats just one of the features of a 70 or 100 volts system, surely if you are going to use many equal speakercabinets, just for esthetic reasons.
The unit price is too high for just trying out.
I've ever seen a low z distribution system for stores. It was built with ceiling speakers, each with an impedance of about 40 (fourty) Ohms.
For a two times 4 Ohms amp, it was possible to connect a total of 20 loudspeakers. , enough for a medium store or restaurant. Since the power needed in a store or restaurant is not very high and cable length mostly do not exeed 50 metres, normal speakercables can be used.


In the video, wiring is not very transparant. For the demo, the speakers could have been simple wired in series/parallel. At time 0:38 two wires seem to disappear in the table. Whats under the table? For me it's an unbelievable story.
 
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I have sold and installed many of my bread-and-butter 100W PA heads, in cheap owner commercial galleries; I live smack in the middle of Buenos Aires La Boca Tango/Tourist district and have the market cornered he he :) , a dozen installations within 200 meters around.

Since many want to spend peanuts, I install the regular 4 ohm output head ,
729947421_3b87010507_z.jpg

have an electrician run 1.5mm^2 speaker type wires to different areas through conduit , short the ends :eek: or connect a single 8 ohm small speaker there (think cheap whizzer cone "full range" or car door type 5" or 6") and along the path I cut open *one* wire (usuallly the Red one) and insert another speaker in series.
Rinse and repeat as needed.
So total impedance remains between 4 and 8 ohm, of course.

As in: 4 lines , 2 speakers each, 8 speakers total, 4 ohm total load, 12W available to each speaker, and so on, mix and match.

Typically longest line is not more than 40 meters.

So I meet "no 70/100V lines" , "light weight" constraints ... I guess I should start charging $31000 each, shouldn´t I? :p

Oh, I see, no "4000W" :(
 
It looks like the amp is a Lab Gruppen FP14000, capable of around 7KW/ch.


If that amp was turned up, it'd be able to exceed the DC rating of their installed capacitor. The problem doubles when you remember the main cap is polarised.
Capacitors don't like being reverse-charged, and tend to make their discomfort known in a big way.

Does anyone else feel this product is seriously unsafe?

Chris

What DC? The only reason that video may be real is that amp: rated for 2 ohms and "Comprehensive protection scheme including current, voltage, DC, temperature, short circuit and open load warnings."

It may be able to drive .25 ohms at lower powers.
 
What DC? The only reason that video may be real is that amp: rated for 2 ohms and "Comprehensive protection scheme including current, voltage, DC, temperature, short circuit and open load warnings."

It may be able to drive .25 ohms at lower powers.
When an amp is goiing in protection, or is current limiting, the output is not an amplifiied copy of the input signal. There's a word for it, distorsion.
 
An amp goes into protection because of current draw, so if the amp can provide 60 amps and its only putting out 10 volts peak it can drive .2 ohms without protection kick in, distortion will probably be higher but not clipping, and again this is not hifi. but you will only get 500 watts out of a 5000 watt amp (estimating).
 
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Hi cbdb,
Some amplifiers use fold-back current limiting (Marantz did) to more closely follow the SOA curve. More protection because low volts and high current always means a load fault. Of course, it was also time delayed to allow for phase angle.

-Chris
 
It's becoming more fantastic. Z-Audio from Switserland states not only that you can connect up to 40 loudspeakers , but also a shortcircuited loudspeaker has no influence. Real magic!

ZERO OHM - Z-AUDIO



Aus Kanada kommend, präsentierte ZERO-OHM erfolgreich ihre neue "Magic Box". Es hat schon fast etwas mit Magie zu tun, denn das Gerät ermöglicht bis zu 20 Stück niederohmige Lautsprecher paralell an einen normalen Endverstärker anzuschliessen! Die ZERO-OHM Box hat zwei Kanäle und damit ist es möglich mit einem 2-Kanalverstärker bis zu 40 Lautpsrecher zu betreiben. Dazu kommt noch, dass kurzgeschlossene Lautsprecher keinen Einfluss auf die restlichen angeschlossenen Speaker haben - wirklich "magic"!

Das Gerät gibt es für Leistungen von insgesammt 4'000 Watt und in Kürze wir auch eine kleinere Version mit insgesamt 2'000 Watt erhältlich sein.

Damit ist man in der Lage, komplett auf 100V-Linien verzichten zu können. Die Klangqualität steigt dadurch merklich und es können auch grösser dimensionierte Lautsprecher zum Einsatz kommen. Wenn man dann noch die Ausfallsicherheit bei Kurzschluss dazugewinnt, dann schlägt bald die letzte Stunde für herkömmliche 100V-Installationen.
 
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is this really working: Zero-Ohm_MS-4R.
connect multiple low impedance loudspeakers to a normal audio amplifier, without the use of line transformers.
YouTube

No, because the whole point of high voltage systems is to be able to use cheap thin wires over long distances. With paralleled 8 ohm speakers you'd need thick wires, and also individual fuses to protect against wiring fires.

Putting a toroidal 5:1 step-down auto-transformer in a box isn't rocket science. There may be some smarts for the short-circuit protection, although I suspect they just use the transformer primary resistance for that :) They claim a patent, but can't find the patent number anywhere. (There is this one, but its clearly nonsense: EP2688313A1 - Passive loudspeaker multiplexer
- Google Patents
)

I note they use neutrik SpeakON connectors rated at 40A rms for their outputs, which with 20 8 ohm speakers in parallel is a limit of 640 watts into 0.4 ohms, much less than the 2000W they claim.
 
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