C2A XLR conversion
- Thread starter pure love
- Start date
Paul Joppa
Moderator
Easy way is to get a 1 : 1 SE : balanced transformer
Would the solution be the same for the RCA input?
For RCA inputs, you'd want to use a higher impedance output transformer. For headphone output, you'd want to consider the output impedance of the amplifier and the load impedances of any headphones you intend to use. This would generally defeat the purpose of an OTL amplifier though.
XLR outputs is soldering in a different connector. Providing a balanced output is defeating the purpose of an OTL.
Maybe I'm misunderstanding when you say it defeats the purpose of an OTL, but in replacing the input RCA with an XLR, if we were okay with adding a transformer to the input, what exactly would be needed to make the XLR input usable?
Additionally, if the benefits of a balanced connection weren't necessarily desired and an XLR was soldered in the RCA's place for convenience, would that work safely with an upstream true balanced source or would there be reprocautions?
Additionally, if the benefits of a balanced connection weren't necessarily desired and an XLR was soldered in the RCA's place for convenience, would that work safely with an upstream true balanced source or would there be reprocautions?
Putting transformers at the output of an OTL amp defeats the purpose of having an OTL amp. The transformers at the inputs don't exactly do that.
Whether you can wire a source to an RCA jack without a transformer is really a question that should be asked of the manufacturer of the source component.
Whether you can wire a source to an RCA jack without a transformer is really a question that should be asked of the manufacturer of the source component.
If you add a transformer at the input of the C2A, then you will be able to use your balanced source and XLR cables. You will reduce the noise picked up by the cable between your source and the C2A, and you can break a ground loop between the two if such a thing exists (which it shouldn't). There will be no difference in the noise as it relates to the circuit itself. You will almost certainly lose some bandwidth by doing this though, and the input impedance of the C2A will drop for that input.
Okay, thanks for your time, Paul. Would the difference in bandwidth be drastic enough that this wouldn't be worth doing, even if the XLR are still meant to only be a convenience for the user? And how will that drop in input impedance come across in listening--would it show up as a loss of a couple decibels of volume, a quieter output, or something else; would it result in any changes to how the amp would be placed in a system?
Lower input impedance means that you are presenting a more difficult load for your source to drive. The input impedance would drop from around 50K to more like 10-15K, so you'd want a source impedance of no more than 1000 ohms or so. If your source impedance is nice and low, then that will help mitigate the bandwidth issues and any perceived loss of signal level. If your source impedance creeps up, then the bandwidth issues become more present and signal loss can become audible.
pure love
Member
@Paul Birkeland Do I understand this correctly; I can solder in an XLR instead of the 6,3mm to connect my headphones even if its still an asymmetrical signal going through?
You could also use a 6.3mm to XLR adapter.
