transformer build thread

[nige2000]

im inclined to go 1:1 but 1:1.6 is fine too if theres no negative effects

[abraxalito]

1:1.6 has the advantage you can turn it round if you ever need 4dB attenuation. 1:1 is boring in comparison...

[nige2000]

lol
wouldnt want to be boring:)

[nige2000]

https://www.aliexpress.com/item/5sets-l ... 8908635863

say theyd make to order

[abraxalito]

If they're making them then we can specify much smaller diameter wire and hence use smaller cores. Want to give it a go?

[jkeny]

If they're making them then we can specify much smaller diameter wire and hence use smaller cores. Want to give it a go?

Sounds like a good plan depending on their pricing
Would same spec transformer be needed for PCM5102 DAC output?
What about TDA1387 DAC output (probably buffer before it?)

[abraxalito]

Let's list the requirements and see how many we can fulfill with one trafo, it can have a few taps (depending on the bobbin's complement of pins).

So do we want only unbalanced output and 2VRMS? Or how about allowing 1VRMS output for better compatibility with direct feeds into poweramps (where the DAC's the volume control) ?

Then the primary needs to be at least 2VRMS but perhaps 4VRMS if you're using balanced DACs in anti-phase.

[jkeny]

Let's list the requirements and see how many we can fulfill with one trafo, it can have a few taps (depending on the bobbin's complement of pins).

So do we want only unbalanced output and 2VRMS? Or how about allowing 1VRMS output for better compatibility with direct feeds into poweramps (where the DAC's the volume control) ?

Then the primary needs to be at least 2VRMS but perhaps 4VRMS if you're using balanced DACs in anti-phase.

Good questions. Got a stinker of a cold & heading o bed. Will mull over & get back to it tomorrow.

[jkeny]

Can't a trafo perform balanced & single ended duties by connecting the two side of the secondary balanced windings in series?
What are the design restrains to doing this?

[nige2000]

Let's list the requirements and see how many we can fulfill with one trafo, it can have a few taps (depending on the bobbin's complement of pins).

So do we want only unbalanced output and 2VRMS? Or how about allowing 1VRMS output for better compatibility with direct feeds into poweramps (where the DAC's the volume control) ?

Then the primary needs to be at least 2VRMS but perhaps 4VRMS if you're using balanced DACs in anti-phase.

would a power amp not need more than 1vrms, would have assumed that would be approx where moderate vol levels would be

surely would be safer going with 2vrms output transformers?
i doubt we will be using balanced dacs in anti-phase any time soon