BOJACK EE-14 8 Ohm Audio Transformer 1300 : 8 Ohm for Voltage Amplification and Power Output (Pack of 10)

Arrived new.

600:600 versionI'm using these in a DIY direct box for a stereo mic (AT822). The mic brings the 2 unbalanced signals out on an XLR connector as ground, left, right (1, 2, 3), and has a specialized cable to break the 2 signals out into individual 1/4" plugs. These x-fmrs are used to convert that unbalanced signal into 2 balanced signals, in a single box, with the single XLR input - rather than needing to bring 2 identical DI boxes and the custom cable everywhere.For the price, I wasn't expecting it to sound as good as it does. There is no noticeable difference in the audio. Keep in mind that this is with a mic level signal. I have not tried these with a line level signal (or anything hotter for that matter).HOWEVER, don't bother trying to pass DC through these. I tried using this x-fmr in a class A tube circuit (12AX7 preamp), and although the tube was drawing barely 0.5mA, the core saturated and there was no bottom end below about 500Hz. So AC signals only for this one folks.

-0.3 dB loss through most of the audio range at around 0 dBm. Increases to -0.7 dB at 125Hz and up to -3.2 dB at 20Hz. Used it to add an isolated balanced audio output to a Boss Katana MKII amp. Might be a bit sus mechanically, would work best if soldered into a PCB. Other than that, a great little 600-600 xformer.

Primary DC resistance is 80 ohm, secondary DC resistance is 3 ohm. 100mV pp 1Khz sine wave produces 20mV pp. Voltage ratio seems to be 5:1 so that would be 25:1 impedance ratio, or 200ohm:8ohm. Attenuation seems flat to 400 kHz. Could use this for switching converter experiments, in addition to audio matching. Might be fun to try for transformer saturation guitar tones.

I used 6 in a home built, 6 channel, ground loop isolator. Output seems as good as it does without it.

Leads could have been attached with more care considering future manipulation. Would advisea continuity test before/after insertion and soldering. Seem a little delicate.Will see how they perform.

Great little signal transfer transformers. I tried to source them via the supply channels people would normally use for components and either they are difficult to find via specs or those companies don't offer these. I even wrote their support - didn't think to check Amazon first. Of course they are here!I used this to act as a signal transfer transformer to trigger a device from this ESP32 gizmo and this transformer is the only means I was able to convey the digital output from the ESP to the other circuit.

It has a sufficient audio frequency response. It has high efficient quality in that bandwidth. But because of its small size in the lower frequency around 20Hz, it has a little distortion.