Dear Sirs,

My set-up as follows:-

Computer as source (wavelab 6.0) (usb output)
M-audio fast track pro (convert usb to coaxial - apogee cable)
Lavry DA11 (coaxial in & balanced XLR out)
MC2 MC1250 power amp
Harbeth Monitor 40 (4 ohms)

It is shown in the manual of MC1250 that its sensitivity for rated output (4 ohms) is +6dBu (1.54v). Hence, the proper maximum volume of DA11 is around 40 by referring to the manual of DA11.
On the front panel of MC1250 there are two rotary peak level encoders so that I can adjust the volume. But I still prefer using remote to the control the volume via DA11. I found that when I turned the volume of MC1250 to maximum (i.e. peak level to 0dB), the sound was already very loud when the volume of DA11 was set to around 28.
Is the sound quality of setting the peak level on MC1250 to 0dB and limiting the max volume of DA11 to around 30 better than turning down the volume on MC1250 (lowering the peak level) and increasing the volume of DA11 to maximum 56?

Many thanks

Ken

Thank you for contacting me directly by email at: techsupport@lavryengineering.com

Here was my answer:
"In a situation like this, the optimal settings are usually a combination of some attenuation at the power amp and keeping the maximum level setting of the DA11 below “56” or the Absolute Maximum input level of the amplifiers.

The best place to start is to set the DA11 to “01” and adjust the attenuators on the amplifier until you achieve a workable acoustic “low volume” from the speakers. I would recommend contacting Harbeth to ask them for the “Absolute Maximum input level” before the attenuators; because it is possible that if you use some attenuation, you will still not achieve the same maximum output level as the rating of 1.54V with no attenuation. It is also possible that 1.54V is the “Absolute Maximum input level;” but there is no way to be certain without contacting the manufacturer. If the Absolute Maximum input level is higher than 1.54V, it could allow you more adjustment range (above “40”).

If turning the attenuators on the amplifiers down affects the quality in a noticeable manner with the DA11 set to “01,” try setting the DA11 to Unbalanced Pin 2 Hot mode (turn Pin 3 “off”). Please be sure the amplifiers are “off” when you change this setting- it could produce a “pop.” The balanced input of the amps will retain the vast majority of their noise rejection qualities, and the resulting level will be 6dB’s lower. This would allow the amplifier’s input attenuators to be raise 6 dB’s for the same acoustic level/DA11 Volume setting."

Brad Johnson
Lavry Engineering Technical Support