Transformer/Summing box help!

[pjleavitt]

Hey everyone!  So about 2 years ago i built a summing mixer using 10k:10k edcor transformers in to a "Classic API  2 Channel ACA & Booster"
that went off without a hitch and everything works great!

Now i've come upon 8 triad A-67J 600:600 transformers that i was thinking about adding to the summing box to get a different flavor if i wanted so before wiring them all into the summing box i simply wired them to some DB25 Dsubs at 600:600 and basically just patched them in between my interface and the inputs to the edcor's on the summing box just to see what they sounded like.  Now for some reason the volume has gone up a ton and all the high end is gone...

Is there some sort of issue with running the 2 sets of transformers?  interface -->600:600triad --> 10k:10k Edcor --> 2 Channel ACA & Booster?

The Edcor's are in the unit to unbalance the signal to send to the  2 Channel ACA & Booster so the one side of the secondary is going to ground to unbalance, could that have something to do with it?

any help is appreciated as i'm not the most experienced DIY'er!!

Paul

 

[pjleavitt]

anybody?  this is driving me crazy!!

 

[radiance]

So you did wire the triad A-67J correctly?

It sounds like an impedance mis-match. What do the outputs of your interface look like?

 

[pjleavitt]

yea i wired it 600:600... triple checked! 
the interface is a Frontier tango 24 which should drive 600 ohms fine...  right now its going trs 8 channel to dsub snake into the triads out of the traids into the summing box inputs which currently go to the edcors.  Do you think bypassing the edcors could solver the problem?  i didn't think there would be any problems just having 2 transformers going into each other since outboard gear does this all the time when you patch things together....

 

[MikeClev]

Do the Triad 600:600s need to be terminated with a 600 or so ohm resistor to work correctly?

 

[pjleavitt]

hrmmmm, i don't know?  does that just involve putting a resistor across the 2 secondary wires?

 

[MikeClev]

Yes...  then the 600:600 will see the correct impedance on their secondary