Aleph 30 gain

I just did some measurements on my Aleph 30 amplifier.
In the service manual, it says that the gain in single ended mode is 26dB. However in my amp the gain is only about 10 (20dB).
Is there something wrong with my amplifier? I did ground the -input, but I didn't have any speaker or resistor coupled to the output of the amplifier. And I don't have R8 or R1 installed in the circuit.

Isn't the gain of the amp (in SE-mode), reffering to the schematic, set by R7, and R3 in parallel with R6. About 21,92dB?

The service manual can be found here.



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By now there are probably a dozen different layouts floating around. The layout I did was originally for an Aleph 2 with some of the features of the Volksamp 60. I don't remember exactly, but I think I called the thread "Aleph 2 (and others) as a project." Someone asked if the layout would work for other Alephs--I believe the consensus was yes.
Use any layout that makes you happy. I'm listening to four copies (i.e. two pairs of monoblocks) of those boards even as we speak. Sonny Rollins (no, we're not related) on now. Next up: Max Roach.