*Solved* 2nd N72 low output

[BeachB]

I've just built the 2nd of 2 N72s. The first one worked straight off the bat, and the second one does too - however, the second has low output. I had a synth output a sinewave to an amp which was miked, and measured the levels for both N72s on a DAW. The first one registered -4.5 db and the second was -19.7 db. Both channels were cranked all the way up.

Here are some things that have been checked: tests in #44-#47 of the assembly manual passed, the jumpers are consistent, and the wires for the input & output transformers are going to the right points. I read a recent thread involving this issue that indicated someone checked pins 2/3 of CONN1 and found 39 ohms resistance. On both of my N72s pins 2/3 of CONN1 have 51 ohms resistance. Also, following the recent thread Pins 2 to 3 of CONN2 give 0v, Pins 2 to 3 of CONN1 give +47.3v with phantom power on, and Pins 2 to 3 of CONN1 give 0v with phantom power off. Again, from the other thread R16 gives the very low value of 39 ohms on the "bad" N72 and gives the specified 604 ohms on the good one. The markings on the resistors are the same across both N72s and there are no obvious shorts on the "bad" one. I don't have a good explanation for this because I checked all resistors before stuffing. Finally R15 checks out at 1.5K on both N72s.

In contrast to the previous thread, I did not hear what I would call distortion. I did a "check 1-2" voice test and the bad N72 gave a nice rich sheen to the signal, which I assume is the standard pre-amp color.

Regarding the tests about the transistors, I have not done them because I don't have a good understanding of what the collector, base and emitter would be for the various components. Thanks for any assistance.

*Solved* Not exactly sure but I suspect a loose jumper at J2 or something as that's the only thing I undid/redid aside from some general multimeter probing around there and R16. Both N72s now generate same level off of test tone.