Tha is Hannu, I tried to replicate that by using a piece of speaker wire. I slotted it into the socket and tried to jam it in using the ground pin on the actual power plug for the AVR, the. Connected the other end to the act casing by wrapping it round a screw. Didn’t perceive any difference but perhaps I didn’t make connection properly. After I try this DC blocker I’m going to go and buy a ground cable with plug with connecting loop so I can be sure of the connection and see if that works.
1 Like
I took my NAIM kit into the Anthem Shop this weekend. They have good reputation for having a low noise floor, both in their AVR and AVM range. I am thinking of replacing my Marantz SR7015 with either the MRX740 (pre-out) or going all the way for the AVM70.
I won’t go into detail on the AV comparison on this thread except but to say, AVM70 spacious, dynamic & engaging soundstage/cinematics.. Marantz better audio performance.
The main point was that with the AVM70 there was ‘no buzz’, problem solved.. With the MRX 740 there was a slight buzz but very feint. With the Marantz the usual buzz was present.
On the day, the audio performance of the Marantz kept me engaged. I am currently in 3.0 config.. If I had a proper AV room then I believe the AVM70 would be awesome..!
The AVM70 is a great piece of kit..
However if you are only using 3.0 and don’t have plans to go 7.1, as a minimum, then maybe consider whether av or music is your priority.
2 channel av into a good Naim streamer like a NSC222 via optic, would be another option, since you have a NAP300. Better 2 channel quality, rather than multi channel, is worth investigating.
Av systems can develop hum and all cable runs and routings should be thoroughly checked.
I experience hum if anything is out of kilter.
Advice I received was simply to use phono to phono even with Anthem processor and 5 channel amp rather than xlr, with front l/r run via a NAP250DR.
I have recently updated my av thread, maybe take a look?
AV upgrade (from Linn) - Anthem AV + NAP250DR + S400s
I use NAC272 NAP300 for hifi. I added a centre with NAP v175 and am planning to swap my focal arias for Proac Response D48 to go with some D18s for the rears. I will find a proac response cc1 somewhere else. Longer term I plan a pair of Proac response D2s for surround. The D18 and D2 are in separate listening zones but for ‘movie night’ and Top Gun 3 I would bring things together… In the nominal 3.0 or 3.1 the buzz is only with the TV or movies as processing with the avr listens to the info for all the channels instead of processing with hifi processor I ignore too much channel and potentially range. I will check out your thread.
Dear Sound Hound, I will try Marantz 2.0 to NAC 272 with optical cable. I’m also interested in your comment on your thread of using phono cable to din for interconnect from AVR…
phono to phono…no din or xlr utilised! as always…keep it simple!
1 Like
Please please please, watch out for this.
I’m not sure about the latest Naim equipment, or indeed anything but my own situation to be honest, my AV amp seriously compromised my 2 channel system. You don’t need hum or other obvious symptoms, just be very diligent and take time to listen before and after AV connections are made.
I’ll get back in my box now 
I think the AV box is just for processing multi channel. The hum/buzz in my case is only when using AVR pre as input. For hifi the AV is not selected and when so there is no hum/buzz. FYI AV processor without the power amp section = no buzz. Not saying i’d use AV processor for hifi, just good tno know the absence of power amps in the AV box leads to no buzz.
Hi musta
Yes, understand. You may have missed what I was trying to say.
Whenever you connect something into your Naim system you run the risk of creating an issue it the single earth that Naim relies on is compromised.
An example is if your av amp is also earthed and connected to your Naim system by pretty much anything except optical. You’ve then got 2 earths in your music system and I would suggest you listen carefully for an impact.
If you don’t then it’s all good!
J
Thanks Jay. This topic of earth in the naim equipment illudes me. I tried earthing the AVR chassis and it didn’t do anything to the buss so moved away from that approach. I heed your warning but am curious where the earth is in my naim system?
My AV system does not connect with my 2 channel system, which is in another room.
The AV system has a 5 channel amp + Naim amplifier, for the 7 channels of my AV system; all works well. The occasional issue of hum in my AV system, has nothing to do with any Naim item.
1 Like
Quite the system there!
The Superuniti and the 272 would tradionally be your grounds if set to ‘chassis’. Not sure how it’s all working as they share that common wall socket. I’m out of my depth!
1 Like
You know, after reading your comment Jay, i checked the grounding switch. It was set to floating. I changed it to chassis and the buzz went away. Still the usual hiss but that’s fine.
I’d tested this before and it didn’t change anything. Today i got my NAP v175 back from the service centre. Weird thing, it had a 3cm length of loose wire rattling around in there.. It also had a problem with the power switch. They removed the wire which wasn’t supposed to be there and secured the PCBs and secured the IEC AC switch.
The combination of this and the ‘Chassis’ selection on the NAC272 made the difference. I was thinking about moving to an AV8805, or Oppo, or AVM70 to solve the problem.. don’t need to now.
Thank you.
1 Like
Great news!
It has been known to happen - you can sometimes get things stuck in the narrow gap under the transformer. That won’t even dislodge with compressed air…