Impedance Matching / Voltage & Speakers

Hey Guys,

              I have these dynaudio 340's and my amplifier puts out 85w @ 4 ohms and 170w @ 2 ohms. I emailed dynaudio to see if 85 watts would be sufficient and they said it would be ok but it wouldnt unlock the true potential of the set unless i get over 150 watts to them. Now if i use a transformer to match impedance it will raise the voltage and lower the current to the speaker but leave impedance the same... will this damage my speakers? Do you recommend that I try this out and see how it works.

I have gotten alot of information from this site:

http://www.bcae1.com/trnimpmt.htm

But i am still very unfamiliar with the concept of it all, any help would be great. Has anyone used transformers to match impedance before? what was the outcome of it all?

Thanks,

Mike

Yeah I am not trying to drive a subwoofer im trying to drive the Dynaudio 340 set (3 way component set).

Thanks,

Mike

Shouldn't be a problem - in theory.  Use a 1:1.41 ratio transformer, and you'll get about 170 watts to your 4-ohm speakers, without overstressing the amp.  You'll lose a little power from the transformer, since some energy is consumed setting up the magnetic field in the primary winding, but it shouldn't be much. Such "insertion losses" tend to be less than 1 dB.

The problem will likely be size and cost.  A large part of the audio transformer market caters to hobbyists building tube amps for home use, or other similar small-output amplifiers.  The highest-capacity audio transformer I've found so far is only good for 100 Watts, and weighs about 8 pounds.  I couldn't find a cost for the 100W transformer, but even the 30W ones seem to be around $75 each.

I suspect that if there were a market for what you're trying to do, there would be car audio manufacturers all over it, since so many people have amplifiers that are two-ohm stable in stereo, and most car speakers (except subwoofers) are 4-ohm only.  If there were a cost-effective way to impedance-match a two-ohm stable amp to 4-ohm speakers to get the maximum power out of the amp, we'd see ads for such a device plastered all over CA&E and the other magazines.

Scott Gardner