Linking 664 and 552 in 12 channel mode

[Derek H]

OK, did some digging for you and figured it out.. Read pages 109 and 110 from the 664 manual. https://cdn.sounddevices.com/wp-content/uploads/2019/01/664-ug1.10.20.pdf

 

Look at the second paragraph here:

 

So this explains it. The difference is expected and due to impedance shift. You say the Master knob on the 552 has no effect? That's too bad. Perhaps you could have a custom cable made that takes the outputs of the 552 from either the Hirose 10-pin or from the two XLR or TA3 mix outs (wouldn't matter which just an output that can give you the full line level) and then take that into the 664's link input following the wiring diagram in the manual. The Master knob would then work to make any trim adjustments between the two machines. I would still check with Sound Devices to make sure this would work or if you need that 10K resistor in the TA5 to enable the connection or something. 

 

Good luck!

 

I think the best solution, that I'm sure you've considered, would be to buy a used CL-6 for the 664. Or a CL-12 if you can find it and you're working in a stationary mode. Of course that will add more bulk to the setup. What you're trying to do was not originally part of the plan for any of these machines. The link IO port is a nice addition but that was made without consideration for the fact that you might want to do what you're doing with the direct outs. 

[Phillip C Dent]

1 hour ago, Derek H said:

You say the Master knob on the 552 has no effect?

The master knob on the 552 has no effect on the stereo output of the 664.  It only affects the stereo output of the 552.

 

1 hour ago, Derek H said:

I think the best solution, that I'm sure you've considered, would be to buy a used CL-6 for the 664. Or a CL-12

Agreed, but both are hard to find these days, and I found this 552 for $500 and thought it would be worth a try.  It also gives me the added benefits of all the 552 outputs and stereo record capabilities for backup.

 

thanks for your input

[Philip Perkins]

And 5 trafo preamps, which is why I got one to use with my 664.

[Phillip C Dent]

So I talked to Dennis at Sound Devices the other day and explained the issue. After some research he called me back and said that the 10dB discrepancy between the stereo outputs of the 664 and 552 are due to the different impedance of the units. I asked if he could think of any fix for it - maybe different wiring for the link cable or some kind of work around. He said not that he could think of and that’s just the way it is.

[Derek H]

Yup. Did you see my suggestion about trying to use one of the line outputs on Monday?

[Phillip C Dent]

3 hours ago, Derek H said:

Yup. Did you see my suggestion about trying to use one of the line outputs on Monday?

Yes I did. Thank you for that suggestion, but I think that it's more than I want to get into.  I asked Dennis about doing something like this, but he wasn't sure about it.  Linking the two machines together did not give me the results that I expected, but I'm making it work for my application.