Output transformer question.

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Hello everyone.

I have a rather not so professional question which arised also as a consequence of somewhat strange experiment.

I got a hold of broken arc lighter, which had two small transformers inside, glued in epoxy, it seems.
Turns out it had an issue with battery charging and it's value was not that high to try to ressurect it by any means.

Out of an itch I connected the high voltage windings to CSR8xxx Bluetooth receiver module from headphones which I had lying around and the originally primaries now used as a secondaries wired to small earbuds.

Even though volume was quite on a low side, there is something really appealing in sound I gets from this combo.

Technically everything is out of frames, the core material and turns ratio probably is completely not for audio.

Anyways, it seems that I should now compare this to something 'audio grade'.

What are the options on market for such duty, does anybody know?
Do there exist such small output trafos? Say 150-600 ohm primary, 16ohm secondary or something like that?

That small.


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As I dont really have huge DIY scene around here, I bought kilo of welding wire (0,8mm, copper plated mild steel) and cut it into ~5cm pieces for centre of core, wound 10 layers (1500 turns, 150x10) of 0.2 copper onto it and as it is late, for a quick test wound 0.25mm wire, 15 meters I had, as a secondary. Then wrapped welding wire around the coil forming outer core.Sound compared to direct headphones connection was more mellow, with this nice soft bass similar to SE mosfet follower loaded by CSS.
I've also experimented with transformers for driving headphones - I began with 2:1 step down for feeding headphones from my mobile phone. Definitely it improved my enjoyment of the music. I used ferrite cores as they were readily available, and cheap - PQ20 and PQ26 were two I tried.
The advantage of a toroid is very low leakage inductance. The disadvantages are - impractical to wind them yourself and seemingly very small ones aren't easy to find. I have some 10VA for driving headphones, they're the smallest I could find in custom - I'd never consider taking them alongside my mobile.
I ended up with winding small step down transformers, with ability to switch to autotransformer connection (to connect like Pass' M2 does).

Simple step down - exercises mind in stereo expansion equals /quantum physics/ leaving me attached to basic me formula, with pair of Aces in my pocket.

Autoformer connection - seems like magnetic discharge of parallels embedded within stereo paraplexum - duty cycle of two hands for one Heart is possible at price of understanding that "Defensive Personalities" are not easily forgiving the me versus you at 360 degree level.

Normally I use step down mode to enhance the copper by obeying steel core, whom is Iron Man for 2x3 of series 0,68ohm resistors (one for channel) symbolizing that future is expensive electrocharge for everything except linear string of Steel.. Made out of steel.. Stronger than anything.. Perfect for becoming part of psyche that equals Deus est Mortus, Logica Obtinet! (Balanced it works, Single Ended.. It starts with... A-Z)

Whenever I feel like being pushed out of Life due to pressure of every Pi value being eroded by politics of this Time, I use autotransformer connection where my position feels stable like within the Pi of everything that resists while charges, leaving me where I deserve to belong or more like I set/setting myself in that chair.
Then it emerges the Stereo in TimeSpace Continuum and is like Zodiac of Scales comparing the absolute Deus at a Time of being One.
Else I have a small R-core to wind, as I only got one, I am planning to use it for Stereo with heavy microphone/floating PSU biasing, just not this year. My research says that with bipolar supply it must be possible to reflex full stereo into a single point of Mass, therefore with dual rails the amplifier should be called The Duality. :)
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