Balanced to Single Ended converter

[rajan-]

During the last few days of the end year shut down, I am finally getting down to building a quality Transformer (Jensen jt-11p-1) based Balanced to SE converter.

The plan is to make the converter do Balanced to SE (with a pot to reduce gain match). this way we can use the high voltage output (normally excess of 4v) on regular SE devices.

and use the same in reverse (SE to Balanced) I believe this is a technique used in certain pre-amps

some of my personal use cases include.

this can be used on balanced source (Tascam ADDA), that I can connect to SE Head phone amp as well as DIY Pre-amp
I can also use it to connect SE Preamp to Balanced / Bridged mono power amps

This is based on a Jensen input transformer, that can be configured in multiple ways.

So far, I did one channel to see how / if it works ok, and its been a success


next would be to finish second channel and install inside a cabinet

 

[Hari Iyer]

What are the turns ratio ?

 

[rajan-]

What are the turns ratio ?

1:1

 

[rajan-]

Both channels completed.
After successful testing with the head phone amp, moved it to the main speaker system. And called Agam for an inhouse performance

TV -> Tascam ADDA -> Balanced to SE converter -> Pre Amp -> Power Amps

My Amp Camps are Amps are connected in Parallel mono setup, puts out 8 watts with a higher damping factor than Bridged mono mode or Balanced mono mode.

Had to turn down the pre amp volume as input voltage has gone up.
Also had to reduce Sub Gain.

Staggering improvements in performance. The Dynamics and control have significantly gone up.


Next stage would be to change the dual gang volume pot in the transformer circuit to something better, Alps will be natural choice, unless I can get a stepped attenuator at a decent price.

Anyone who has a balanced Source should try this with (may be with a cheaper 1:1 input transformer) and see if it makes a difference to their system. IMHO its a low effort high return gear. and its easier to replace the transformer with a better one later.


the inspiration for this came from a few different places and requirements.
Linn Klimax, Decware, PreAmps with input transformers, pro audio gear / removing Humming

 

[Hari Iyer]

Both channels completed.
After successful testing with the head phone amp, moved it to the main speaker system. And called Agam for an inhouse performance

TV -> Tascam ADDA -> Balanced to SE converter -> Pre Amp -> Power Amps

My Amp Camps are Amps are connected in Parallel mono setup, puts out 8 watts with a higher damping factor than Bridged mono mode or Balanced mono mode.

Had to turn down the pre amp volume as input voltage has gone up.
Also had to reduce Sub Gain.

Staggering improvements in performance. The Dynamics and control have significantly gone up.


Next stage would be to change the dual gang volume pot in the transformer circuit to something better, Alps will be natural choice, unless I can get a stepped attenuator at a decent price.

Anyone who has a balanced Source should try this with (may be with a cheaper 1:1 input transformer) and see if it makes a difference to their system. IMHO its a low effort high return gear. and its easier to replace the transformer with a better one later.


the inspiration for this came from a few different places and requirements.
Linn Klimax, Decware, PreAmps with input transformers, pro audio gear / removing Humming

If you are using a volume pot, then go for a constant Impedance wiring, else your input impedance will keep changing based on the position of the wiper.