N72 Rev 3.0 Now Shipping. Must read!

[lynyrd]

WOuld I be correct in assuming that new parts J5, J6, and D4 are to be installed? My other question would be, is there supposed to be a shunt at J5 and J6?

[tpryan]

You have to install D4 to get +48V for phantom power. Install J5 and J6 if you want to be able to switch input impedance between 1200 ohms and 300 ohms. You'll have to wire T1a pins 2, 3, 4, and 5 to the PCB and install jumpers at J5 and J6 to make that work. Jumpering across J5 and J6 so that T1a pins 3 and 4 are connected gives 1200 ohms. Jumpering both J5 and J6 so that T1a pins 2 and 3 and pins 4 and 5 are connected gives 300 ohms. If that's not clear, check the schematic. If you don't want to worry about these jumpers, just wire the transformer as shown in the current instructions.

[lynyrd]

Thanks for the quick reply

[Karl]

...just got 3 done last weekend and had no issues. I notice that there are no more clicks in the gain switch, nice!!! I hope that's normal (Tim?). They sound identical to my older N72 as well.

Thank you Seventh Circle!!!

[tpryan]

I notice that there are no more clicks in the gain switch, nice!!! I hope that's normal (Tim?)

Yes. Also, you can usually get rid of the pops on a 2.x rev N72 by reversing C12. The PCB pads are small, however, so be careful removing it. Much safer to snip the cap out and replace it if you're interested in trying the mod.

[jmoore]

What's this new option about?

We'll be offering the kit with a custom wound CineMag PC mount transformer instead of the Carnhill part. It'll be much easier to assemble and offer greatly extended high frequency response (-3dB at about 120K). It has a smaller core, however, so it saturates sooner.

The new instructions won't offer anything that isn't already in the sticky except some new photos, which are still at least a week away.

I'm sorry if this question has already been answered, but do you have any sort of ETA on the release of this "new" version?

[Philo]

Install J5 and J6 if you want to be able to switch input impedance between 1200 ohms and 300 ohms. You'll have to wire T1a pins 2, 3, 4, and 5 to the PCB and install jumpers at J5 and J6 to make that work. Jumpering across J5 and J6 so that T1a pins 3 and 4 are connected gives 1200 ohms. Jumpering both J5 and J6 so that T1a pins 2 and 3 and pins 4 and 5 are connected gives 300 ohms.

If that's not clear, check the schematic. If you don't want to worry about these jumpers, just wire the transformer as shown in the current instructions.

Just to be clear, if we do this wiring using J5 and J6, we still install 2 jumpers on the input transformer (6 to 10, and 8 to 9), but leave off the jumper from 3-4. Instead, pins 2-5 all have their own separate wire to the holes, as do 7 and 10.

Is that right?

That's how I did it, anyway.

[analogical]

Learned about the tape and Screws on the backside the hard way >.<

Basically If your N72 is in the rack's #1 slot, beware the mu-metal shielding of the power supply!