NC502MP Amp - Need Help

[possumtaters]

I purchased an NC502MP amp a while ago, just hooked it up, and I’m having trouble liking the sound. My current setup is an Outlaw RR2160 amp, SMSL SU-9 DAC, and Revel F36 speakers. The sound in this configuration is wonderful. Instruments sound sharp and lifelike, with voices, imaging, and soundstage that are amazing. When I introduce the NC502MP amp in the mix everything is dull, with instruments sounding muted and very little stereo imaging/soundstage, like everything is being playing in mono. What’s strange is if I reverse the speaker wires, so everything is out-of-phase, things improve quite a bit, including the soundstage instruments, and voices, but you can tell the sound is not right, especially in the lower midrange and bass, because the speakers are not in phase. I opened the case of the amp and verified that everything is wired correctly, including the speaker connects and balanced inputs. I verified the DAC, amp, and balanced cables (Blue Jeans) all had the same pin out configuration, and also confirmed the continuity for each pin of the balanced cables. Does anyone have a suggestion on what could be occurring or how to fix things? I purchased the amp to reduce the footprint of my system, so everything could be tucked away until I wanted to use it, and so I also had a one and done amplifier, allowing me to stop upgrading and just enjoy the music.

 

[MrOtto]

DAC digital volume control problems? Try using a preamp? Use the pre-out on the Outlaw connected to the Hypex with DAC at 0 dB connected to the Outlaw.

 

[restorer-john]

Unless you can instantly A-B between your amplifiers, it's going to be difficult to isolate or track down what the problem is. A collapse of the soundstage is strange for sure, and, unless the NC-502MP is faulty in some way, that is hard to explain.

But, if the Outlaw gives you what you want and the Hypex doesn't, you'd have to seriously question why you'd pursue the NC-502MP path.

 

[Koeitje]

Sounds like either the SU-9 is doing something odd, or there is something wrong with your 502MP.

 

[MrOtto]

From SU-9 manual:
SU-9's MQA playback does not require additional software. You can use foobar2000 or Audirvana for MQA playback as it supports ASIO or WASAPI audio output. When playing MQA audio, it is suggested to adjust the volume of the computer to the maximum for the best audio output

Why only for MQA playback? Try in DAC mode, and disable PRE MODE, if you use it, and use a preamp. I think there is nowhere around a decent preamp for this level hi-fi sound reproduction.

SU-9 manual:
PRE MODE
Volume control enable or disable.Vol Fixed : In this mode, volume is fixed on max output level, and the SU-9 will ignore the volume operations. Vol Variable: In this mode, volume can be adjust by remote controller, and make SU-9 a pre-amplifier.

 

[Matias]

If you are doing too much digital attenuation, like -30 dB, then consider adding an analog attenuation, be it in the form of a preamp or a fixed in-line attenuator and use less digital attenuation.

To test this try connecting the pre-out from the Outlaw RR2160 into the NC502MP and use the Outlaw as a preamp.

 

[possumtaters]

From SU-9 manual:
SU-9's MQA playback does not require additional software. You can use foobar2000 or Audirvana for MQA playback as it supports ASIO or WASAPI audio output. When playing MQA audio, it is suggested to adjust the volume of the computer to the maximum for the best audio output

Why only for MQA playback? Try in DAC mode, and disable PRE MODE, if you use it, and use a preamp. I think there is nowhere around a decent preamp for this level hi-fi sound reproduction.

SU-9 manual:
PRE MODE
Volume control enable or disable.Vol Fixed : In this mode, volume is fixed on max output level, and the SU-9 will ignore the volume operations. Vol Variable: In this mode, volume can be adjust by remote controller, and make SU-9 a pre-amplifier.

Thanks everyone for your responses. Switching to DAC mode, and using the Sonos app for volume control, was the answer. Everything sounds awesome now!!!