I received this McIntosh C37 preamplifier to assess a complaint of muffled audio. I swept the frequency response of several inputs. I also compared the performance against a C2300 that was also in the shop.
In the photo below the C37 is on the bottom, and the C2300 on top. On the right are the frequency response plots. I used a digital audio interface to generate a test tone and passed it through the unit under test. The audio output of the preamplifier was again fed through the digital interface to the computer. I used SignalScopePro to plot the frequency response. As you can see, the C37 performed well. Check out the flat frequency response of the unit’s tuner input. The EQ applied to the phono inputs, seen in the lower plot, also looks good. This unit measured in the 0.002% distortion range. Very nice!
If you feel that your McIntosh C37 has muffled audio, or if any of your McIntosh equipment is not performing well or sounding “right,” contact Bob the Tech Audio for a thorough assessment and repair.
