I'm using this amp as a sub woofer amp for a passive sub. RCA's run to it from my pre-outs on my receiver. After listening to music and turning off my receiver, the SA-2 amplifier should turn off after 10 minutes of receiving no signal from the receiver. It doesn't. The switch is set properly to activate the standby mode. Other than this problem, the amp works fine.
Does the NHT sa-2 have it's own pre-amp? Because I'm wondering if the power off only works when it's own pre-amp is used? So when your receiver is connected it's shut off.
You could try something connected to it's own pre-amp (if it has one) and see if it goes off when there's no signal from that.
The schematic (rev A, sheet 1, lower right) for the NHT SA2 amplifier shows that the standby mode is activated by either the line level inputs or the speaker level inputs. The line is simply a splice off the 0.67V 50Hz drive prior to any user-adjustable low pass settings on sheet 2 (the high pass settings for "line out" happen after this line is picked off.)
The other option for the standby mode not working is that the switch on the back panel is broken into the defeat mode (the questioner already wrote the switch is in the right position) or the detection circuit (rev A, sheet 5, lower left) has a faulty component. Either of these problems would require circuit diagnostics.
×
Register and download the manual for free at audio.manualsonline.com
http://audio.manualsonline.com/manuals/mfg/denon/rcdm37.html
Self-powered would work but it would have to run on full-range amplifier (from the speaker posts) or Line Level signal (from the OUT RCA jacks) because this unit has no Sub-specific output. It's no bigge as the sub would naturally discard the higher frequencies via its own amp's and speaker
276 views
Usually answered in minutes!
×