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Subwoofer Causing Amp to Stay On

I have an Audio Note Kit 1 300b SET Amplifier driving a pair of very efficent full range drivers. My entire system is plugged into a psaudio p5 regenerator, which plugs into a synergistic research orange duplex(floating ground). I recently added a pair of Klipsch C-310ASWi subwoofers(ungrounded) into my system via hilevel input, connected from my speakers binding posts. I’ve noticed that now that the subwoofers have been added, when I shut my entire system down, my speakers remain on with a slight hiss or static sound. The hiss will stop, and the speakers will turn off, if I unplug the power cord from the Audio Note, or unplug the subwoofers. I was not having this problem before the subs. So obviously they are the culprit. Anyone know what’s going on here? Old school style amp not liking the newer type amplifier inline? What are my options other than go wireless? Should I go wireless(subwoofer has built in option)? I also get slight transformer buzz from time to time from the psaudio p5, and now that my speakers wont shut up when off, it gets expelled through drivers and amplified into the room.
akwilson501
almarg's avatar
almarg
9,670 posts
 
... neutral ... is where the voltage differential is coming from.

Not sure about that. As is the case with most audio components AC neutral just goes to the primary winding of the power transformer in the amp and the subs, and nowhere else within those components, aside possibly for some sort of AC filter in the case of the sub. (Based on a schematic of one of the versions of the Kit1 amp that I looked at it does not have a filter on the incoming AC). And as shown in that schematic safety ground is connected directly to the amp’s signal/circuit ground, and therefore to all kinds of circuit points within the amp. And the same may hold true in the case of the sub, if it has a three-prong power cord and IEC receptacle. Or if safety ground is not connected directly to the sub’s circuit ground chances are it is connected to it via some low resistance, as is done in many designs. With that circuit ground connection in turn very probably going directly to the sub’s negative speaker-level input terminal, and from there to the speaker’s negative input terminal and the amp’s negative output terminal for the corresponding channel.

In any event, the cheater plug experiment is easy enough to do, and might be informative.

Regards,
-- Al


akwilson501 OP
50 posts
 
I was thinking an LOC from the amp to a wireless transmitter(rca) which would then send the signal to my subs. Klipsch makes one specifically for the subwoofers I have. Obviously I'll try the LOC directly to Subs first and see if that solves anything. Any opinions on wireless for subwoofers, if all else fails? A cheater plug will be the first thing I try tomorrow. Will update upon further trial and error. 
andrewkelley
276 posts
 
Try connecting the high level input to the amp instead of to the speakers binding posts. Also, are you using LFE out from any processor to the subs, this can cause issues. If none of that works try grounding the subs to the audio note w any extra speaker wire you have. Just a simple connection from chassis to chassis 

I’ve been in this same situation 
amg56's avatar
amg56
887 posts
 
Reading the OP’s initial post, the subs are connected to the speakers binding posts. Therefore, even when the amp is off, there is a current being initiated from the subs to the speakers.
The subs speaker cable need to be disconnected from the speakers and plugged into the amp LFE outputs. Or use the wireless option. I had a pair of REL subs and used their wireless option quite effectively. Plus I could place them in the room more effectively.

Anyway back to the issue, you are getting signal feed from the subs, which are
still powered in standby and “still listening” for the signal to take them from standby to ON. Your main speakers are playing the sub signal.

No huge problem, but don’t connect the subs to the speaker posts.

AG 🇦🇺




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