Electronics > Projects, Designs, and Technical Stuff
Calculating transformer winding ratio for 600 ohm > 8 ohm
(1/1)
RockyRaccoon:
I have designed an amplifier with an output impedance is around 600 ohms. I want it to drive an 8 ohm speaker, so I am trying to calculate the proper transformer winding. I’m finding very little information on this so I’ve come here to ask for help — how do I calculate the proper transformer winding ratio to turn a signal with 600 ohms of resistance to a signal with 8 ohms of resistance? If it’s a common enough ratio I’ll order it but if not I have a machine that I use to wind guitar pickups that I’ll use to make it myself. Thanks!
Benta:
The rule is that impedance transformation is the square of the winding ratio.
In your case sqrt(600/8) = N.
RockyRaccoon:

--- Quote from: Benta on January 25, 2019, 06:27:39 pm ---The rule is that impedance transformation is the square of the winding ratio.
In your case sqrt(600/8) = N.


--- End quote ---

So I’m understanding you properly, the ratio should be 8.66:1?

600/8 = 75 and the square root of 75 is 8.66

Thank you.
DaJMasta:
Exactly.  You can find RF transformer calculators around the net that will confirm this, also can give you an idea of losses for a given core material.  Here's one that gives you a bit more than just turn ratio, but there are many options: https://www.changpuak.ch/electronics/broadband_transformer_matching.php


For good low frequency response, you're going to want a good number of turns.
floobydust:
You won't get a lot of power, maybe a few W at most unless your 600 ohm source is capable of a lot of output voltage, like a Pultec EQ.
To experiment, a 120V-12.6V power transformer is around 9.5:1 turns ratio. So 600 ohm input and 6.6 ohm output.
Navigation
Message Index
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod