NAD M33

The output level of the M33 is lower for a given decibel reading than you’re used to. If you are getting adequate volume at -20 dB, you still have 20 dB of room, so it seems there’s nothing to be concerned about.

The decibel readings on a preamp are in a sense arbitrary, and often are related only to the unit’s maximum gain.

From an engineering point of view, usually it is considered better for signal-to-noise ratio to be running any volume control at a higher, rather than lower, level. It means less gain is being thrown away.

If it were me, I’d be more interested in the sound quality at my usual listening level than the knob position required to get to that level. The exception would be if you can’t get enough volume to suit you . . . then, there would be a problem.

Thanks Mike. My typical listening ranges from 70-80dB SPL - occasionally louder. And that is the range where the amp really does start to open up; listening at 90 dB SPL is pretty loud but at that level it sounds terrific, so your explanation regarding an engineering point of view makes sense perfectly. 

What is the output of the phono cartridge that you are using?

I have an Audio Technica AT150SA cartridge:

Output Voltage: 4.0 mV

Load Impedance: 47 kΩ

Load Capacitance: 100 – 200 pF

Hi Freezoner

@mike_in_nc is correct - the volume indication is not something you should worry about. Think of it this way: when it indicates -65db - it is suppressing the line stage input to the amplifier by 65 db (not referring to how loud, but how much attenuation of the signal). For most speakers, it would be barely a whisper. I’m guessing 0 db through your Klipsch Heresy’s would border on painful.

I used to own the M33 in a system a while back and it was typical to run the volume between -35 up to -20 (with somewhat inefficient speakers). At -20, it was louder tthan I wanted for most music. Dbs are how professional rigs measure signal suppression.