Distributed Horn Speaker system, Pwede bang ordinary transformer?

[Woots29]

may isesetup kami na 20 pcs na horn speakers

im thinking of using 70 or 100v transformers

pero triny ko ung 12-0-12 12A as input to amp then 110 output nya

while connected to horn 12-0-12 2a

gumana naman. pero suitable na ba ito? 

[labgruppen]

pwede sya siguro with amplifier power up to around 70W(@8ohms). tapos mas maganda siguro mag insert ng HPF (fc at 120Hz or higher, 24dB/oct) sa input ng amp. ngayon yung horns mo dapat ay connected sa 0-12 lang tapos yung 0-220V ang gamitin mo na taps. this way with 20horn/traffo combo hindi mao-overload ang amp mo (assuming minimum 8ohms ang amp mo).  sample illustration below with horn speaker @16 ohms.



btw, anong amp ang gagamitin mo? baka kaya nyang mag drive ng 70/100V systems directly without transformer sa bridge mode. this way yung transformer per loudspeaker na lang ang kailangan mo.

[Woots29]

100 watts per channel ang gagamitin ko sir. kungsabagay stereo naman yung amp, divide nalang sa 10 horns per channel.

may nakita akong amp nun sir na may cap between amp and trafo. pwede bang ganun sir?

anyways sa expenses hindi ko sure baka mas mahal ung ganito kesa 70volt systems

any ideas sir? +1 for ilustration

[labgruppen]

kung bridgeable yung amp, i prefer the setup below..



this way, mae-eliminate main traffo, thus lower cost and lower power losses.

sa unang config, yup pwedeng mag series ng cap between traffo and amp.  pwede rin sa config sa taas, between amp and line.

regarding costs, baka mas mura ang power transformer kaysa sa audio transformer kasi yung audio transformer designed to operate at frequencies way lower than 60 hz, thus bigger core and higher cost. tapos kung bridgeable pa yung amp, yung config sa taas ay sa tingin ko ay mas mura na kesa sa dedicated amp and parts (traffos) na pang 70V system. Yun nga lang you can't go lower than 60Hz, pero ok lang since horn loudspeakers can't go that low.

[Woots29]

baka 100 meters apart horn speakers sir ok lang bang walang main trafo?

sa tingin ko di ko p[wedeng ibridge sir kasi baka ayaw ipagalaw ung amp.

konzert 502 ung gagamiting amp

[Woots29]

BTW

trafo resistances available here:

12-0-12,12 amps         0-110-220

 0.5ohms                     15.5 ohms   

12-0-12, 2amps           0-110-220

1.4 ohms                      123ohms

[labgruppen]

ic, 4 ohms stable ba yung 502?

[Woots29]

ic, 4 ohms stable ba yung 502?

opo. kaya nya ang 4 ohms

[labgruppen]

ok.. baka ayos na ito. 10 speaker per channel. equivalent to 6.4 ohms (ideal computation) loading per channel. since mababa yung dc resistance nung 12-0-12 12 amp traffo,  kailangan nga talaga ng capacitor. (magdradraw kasi ng malaking current kahit sa output dc-offset voltage lang ng amp. series caps prevent this)



EDIT.
BTW, since medyo malayo yung distances, pwedeng gamitin yung 220V sa lahat ng traffos (instead of 110V) to further minimize line loss. and 120Hz HPF before the amp is still highly recommended kahit may capacitor na sa output.

[Woots29]

ok po maraming salamat. report ko ito ke boss update kita sir

[tony]

yung traffo connecting to your amp's output should have bigger cores than those traffos feeding the satellite speakers....

[tony]

100 watts per channel ang gagamitin ko sir. kungsabagay stereo naman yung amp, divide nalang sa 10 horns per channel.

may nakita akong amp nun sir na may cap between amp and trafo. pwede bang ganun sir?

anyways sa expenses hindi ko sure baka mas mahal ung ganito kesa 70volt systems

any ideas sir? +1 for ilustration

kung 100 watts at 4 ohms yan, voltage is 20, so your choice of 24 volts is good......to mitigate the effect of output offset voltage, capacitors in series is used, imho, just one cap will do...

then 24 : 220 has a ratio of 9.1, the impedance ratio then becomes 1 : 84, so that a 4 ohm is reflected as 335ohms at secondary....

for the satellites, i suggest you use multi-taps instead....220/12,9,6,4,3,

taken together the impedance's of the 10 satellites should add up to 335 ohms to make s good match...

[tony]

^so 10 satellites should have a reflected impedance of 3350 ohms primary each,using 16ohm satellites,  turns ratio of transformer then becomes [3350/16]sqrt = 14.5

so a 220v/15volt small traffo is actually needed...but a 220/12volts will work as well....

[Woots29]

yung traffo connecting to your amp's output should have bigger cores than those traffos feeding the satellite speakers....

yes sir. mas malaki core nun

we followed the schematic in reply #8 kaso

huli na ng mabalitaan kong naka 24v lahat ng trafo

sa ngayun di pa ginagamit ung sinetup namin

pero any big effects dun sa 24v out?

[tony]

^that will work....

[Woots29]

ok thanks sir kungsabagay may fan naman ung amp +1

[Woots29]

heto po ngyari sa amp

[j a y k e z]

OT: boss woots more pecture please

+1 sa mod  

[Woots29]

cge later