impedance matching transformer

[masudasim1]

Hi all

I have a QSC  audio amplifier (RMX 4050HD) and an acoustic transducer having input impedance of approx 180 oham at resonant frequency. QSC amplifier can provide about 2000 watt to 2 oham load (speaker) . If i directly connect transducer to amplifier, i only get 50-60 watt output. I require atleast 600-700 watt power  so i need a matching transformer (probably step-up transformer) b/w transducer and amplifier.

Can any one kindly suggest charecteristic parameters (e.g. winding ,core , insulation etc) of transformer most suitable for my application?
Is there any software availavle for design of such transformers?Most software available on net are for RF matching transformers

Note:My operational frequency band is  about 3-5 KHz

Best Regards

 

[Hero999]

Does it need to be a sine wave?

There are probably cheaper and more effective options such as an h-bridge IC designed for motor control.

 

[masudasim1]

Thanks for reply . Yes it needs to be pure sine wave with as less distortion as possible

 

[Hero999]

You need to have a peak voltage of at least 502V to get 70W RMS into a 180 Ohm load. The amplifier would have to be designed for 63kW RMS into 8R for that voltage. You won't be able to find an audio amplifier with that power level.

You could use an impedance matching transformer with an ordinary audio amplifier or build your own amplfier. I don't know what's the best core material to use for 3kHz to 5kHz, it's a little on the high side for laminated steel but is low for ferrite.

The Wikipedia article linked below gives the formula for a calculating the turns ratio.
http://en.wikipedia.org/wiki/Impedance_matching

The minimum number of turns on the primary is determined by the peak flux density the core can handle before going into saturation. This occur under the highest powrer level, at the lowest frequency.
HEre are some articles with the calculations you require. THe theory is basicaly the same for any transformer with a magnetic core.
http://focus.ti.com/lit/ml/slup126/slup126.pdf
http://www.fairchildsemi.com/an/AN/AN-4140.pdf
http://en.wikipedia.org/wiki/Transformer
http://ludens.cl/Electron/trafos/trafos.html

 

[masudasim1]

Thanks for the reply and material you provided.