Converting stereo single ended to balanced mono?


Hi, I have three Thiel 3.5 stereo equalizers (bass boosters). These are single ended only. I was wondering about the benefits of trying to convert two of them to balanced mono operation. Is it possible? Is it worth it? What are the options for doing this? What are the pros and cons of these options? Are there any other upgrades that might be considered if and when these conversions might be done?

https://www.stereophile.com/content/thiel-cs35-loudspeaker-measurements

As always thanks in advance.

unsound

Showing 1 response by atmasphere

You could do this with some modification, but there really isn't a good way to do it otherwise. The problem is that you have to invert the signal to one channel in order for a balanced output to be produced from the pair of channels.
One way do solve that, assuming a single-ended input, is to wire the input circuits of the two channels as a single differential amplifier- with each output then driving their respective channels. This assumes a discrete solid state circuit. And you might need a negative power supply to make it happen.
Another way would be to use an line transformer driving the two inputs. This is by far the easiest way to do this but the transformers that are worth it aren't cheap. Jensen makes the best- its either that or Lundahl. If the secondary driving the input of the EQ has a center tap that would be helpful, but a pair of resistors would do as well.  PM me if you need more info.