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Marco
30-12-2015, 19:38
Sorry for the daft question, but it's something that's always confused me, if an SUT has 20db worth of gain, what is its step-up ratio? Conversely, if an SUT has a step-up ratio of, say, 1:10, how much gain does it have?

Cheers! :cool:

Marco.
CageyH
30-12-2015, 19:45
Useful page here:

http://www.sengpielaudio.com/calculator-amplification.htm
Arkless Electronics
30-12-2015, 19:48
20dB is x10 ;)
In a 1:10 step up the turns ratio will also be 1:10 i.e. if there's 100 turns of wire on the primary (cartridge side) there will be 1000 on the secondary.
The impedance transformation is the square of the turns ratio though... just to complicate matters
Marco
30-12-2015, 19:49
Useful page here:

http://www.sengpielaudio.com/calculator-amplification.htm

Cheers, but I've no idea how to use that (dunno the required input info). Essentially, I just need a direct answer to my questions :)

Marco.
Marco
30-12-2015, 19:53
Hi Jez,


20dB is x10 ;)


So does that mean the step-up ratio is 1:10?


In a 1:10 step up the turns ratio will also be 1:10 i.e. if there's 100 turns of wire on the primary (cartridge side) there will be 1000 on the secondary.
The impedance transformation is the square of the turns ratio though... just to complicate matters

I hear ya, mate. Just trying to work out the gain on something :)

Marco.
Arkless Electronics
30-12-2015, 20:02
Hi Jez,



So does that mean the step-up ratio is 1:10?



I hear ya, mate. Just trying to work out the gain on something :)

Marco.

Yes.

But remember that dB are logarithmic. 40dB would be 1:100, 30dB 1:30 and 60dB 1:1000
It's different again for power ratios :D
Marco
30-12-2015, 20:22
Ok, cheers. I get that.

Just to double check... So, the higher the step-up ratio figure, the more the gain, i.e. an SUT with a step-up ratio of 1:20, will have more gain than one rated at 1:10, yes? :)

Marco.
Arkless Electronics
30-12-2015, 20:38
Ok, cheers. I get that.

Just to double check... So, the higher the step-up ratio figure, the more the gain, i.e. an SUT with a step-up ratio of 1:20, will have more gain than one rated at 1:10, yes? :)

Marco.

Indeed. If the number before the : sign is one then it's the same as saying x10 or x20 voltage amplification.
Marco
30-12-2015, 20:49
Ok, cool! :thumbsup:

Marco.