Upgrade insert (old mixer)

[matthopkins]

Hello how are you? I'm new to this forum. I have an old 70s mixer (Hudson csl) it is cool and I like the sound (melodium transformer) I plan to improve some points because it is asymmetrical (-10dbm) and it bothers me on the inserts outputs, the level Is -6dbm which is very fair for my compressor. I would have liked to know if you have a solution to it? I thought of putting a small amplification system on each insert but perhaps you DIY pro have a more interesting solution?


This is what I found as a schema, but I do not know if it would fit for my case
https://sonelec-musique.com/electronique_realisations_preampli_ligne_002.html

I attach the console diagrams

Thank you. 

 

[moamps]

The simplest solution is to use a voltage amplifier with  6dB or so gain based on a single opamp (5534 type), powered from channel strip's power supply (+/-17V) and built on a small board attached somewhere on the channel strip. (or using half of the second schematic on link you posted for each channel strip, for example)
The amplifier should be inserted on position of  R23 (330ohm).

 

[abbey road d enfer]

In addition, you'll need to attenuate the return signal by the same amount. You don't want to do that passively, because the tone controls want to see a low impedance source. So you need to insert an attenuator and a unity-gain buffer before capacitor C9.

 

[KrIVIUM2323]

Maybe you could use That 1206/1646 balanced line driver/receiver(if you want to go balanced for your insert sends/returns)?

 

[abbey road d enfer]

Maybe you could use That 1206/1646 balanced line driver/receiver(if you want to go balanced for your insert sends/returns)?

Technically, it's an excellent solution, but practically, it involves adding one 1/4" socket.

 

[KrIVIUM2323]

Abbey road,
yeah you are right.

And if you take it from a cost point of view it can built up pretty fast as the OP should have to build a separate box and probably another ( pair) of psu to power them up.

This said it really solve the gain and balancing problem with just two chips (by channel) and some capacitors/resistors on a perfboard, with really good transparency.

 

[matthieu68]

Hello, I apologize for the delay, the response notification went into the spams. Thanks for your reply a T pad at the entrance would not work from the blow?

Now in the meantime another idea had come to me, if I take my output direct output I recover these 6db missing, I just have to enter a new tracks.

But by this method my compressor Retro me still delivered too much signal, despite the output at minimum, in this case a T pad could do the trick?

Thank you again and again sorry for the delay