Anthem AVM70 Review (AV Processor)

[peng]

Just curious:
Is there a comparison/measurements of AVM 70 SINAD of RCA vs XLR? I know AVM 90 performs better on RCA out...
The unit tested by Amir in this thread seems to be the early with AKM DACs. Later Anthem switched to ESS - is there a measurable change in SINAD, or about the same? Has anyone measured?

Trying to understand how much I will lose, if I switch to XLR cables to resolve the humm/buzz. I purposefully purchased RCA cables in the hopes to be better, did not expect humm/buzz from speakers...

I used RCAs for a few months before switching to XLR, never had hum/buzz issues with RCA. Imo, you should try to find the root causes first and solve it, balanced output don’t really eliminate the causes it just cancelled it though not always completely. As to SINAD, going to XLR you may lose a couple dB but may be not, assuming you could fix the hum/buzz issue. I expect the units that use the ES038Q2M will do better on the bench but I would not expect audible differences.

 

[ban25]

Hi all!

I received my AVM 70 today, and I am joining the club of proud owners.
Setup was easy, I am yet to calibrate with ARC Genesis.
I have one problem and I am looking for help.
There is very slight but annoying hiss/buzz from all speakers, constant and not changing with volume +/-. It is bearly audible at the MLP, but distinct at close distance less than 1/2 meter.
I would like to eliminate this noise. Let me describe the setup.

1. All interconnect cables are RCA at the moment, lengths are from 0.5 meters to 0.75 meteres. All HDMI cables are 8K certified But cheap brand HAMA, lengths are 1 and 2 meteres.
2. AVM 70 L/R and Subs L/R preout are connected to STR preamp for HT Bypass.
3. AVM 70 Center and Surround L/R are connected to MCA 525 Gen2.
4. HDMI sources: a) Blu-Ray Player; b) Dune HD Pro 8K.
5. HDMI eARC to TV Samsung QN900B.
6. Anthem STR L/R preout are connected to STR amp.
7. Anthem STR Sub L/R out are connected to a pair of subwoofers.
8. All equipment is plugged into the same power bar, which has NIF filtering, surge protection, and DC blocking.

I did troubleshooting, and narrowed down the source of hiss/buzz to be the HDMI eARC connection to the TV.

If I unplug the HDMI eARC from AVM 70, there is no noise whatsoever.

TV has only two cables plugged HDMI eARC and cable TV.
Unplugging the cable TV does not make a difference, it is an optical cable to the TV box, and a short antennae cable to the TV.

Question: will a better HDMI cable eliminate hiss/buzz?

Additionally, I have some XLR cables, and tried them out. I connected AVM 70 L/R pre out XLR to XLR of STR preamp. The hiss/buzz from L/R is eliminated to about 98% - still some, but it is more a hiss now, and only audible at a distance of 10-20 centimeters. Noise from centre and surround channels remains, as they are still connected via RCA.

Please help with above, how to eliminate the hiss/buzz from the system.


View attachment 495136

You have a ground loop being introduced by your TV through the copper HDMI interconnect. It could be caused by your TV being on a different circuit from your AVP/AMP, or it could be caused by something else connected to the TV. If you have a cable TV connection, that is a common source of problems.

The easiest fix is to switch all of your AVP/AMP interconnects to XLR.

 

[peng]

You have a ground loop being introduced by your TV through the copper HDMI interconnect. It could be caused by your TV being on a different circuit from your AVP/AMP, or it could be caused by something else connected to the TV. If you have a cable TV connection, that is a common source of problems.

The easiest fix is to switch all of your AVP/AMP interconnects to XLR.

I agree, but I am ocd, if I had a ground loop issue I had to find the reason, it could be something as simple as rearranging the interconnects and other cables, but it could be time consuming to find the more complicated ones so XLR is often a quick fix for normal people lol..

 

[vddobrev]

I used RCAs for a few months before switching to XLR, never had hum/buzz issues with RCA. Imo, you should try to find the root causes first and solve it, balanced output don’t really eliminate the causes it just cancelled it though not always completely. As to SINAD, going to XLR you may lose a couple dB but may be not, assuming you could fix the hum/buzz issue. I expect the units that use the ES038Q2M will do better on the bench but I would not expect audible differences.

I agree, must find the root cause. In a way, I already know it, it is the TV HDMI connection, eARC out from AVM70, to eARC in on the TV. If this is unplugged, noise is gone.
TV is with 3 prong plug, Anthems are with two prone plug...
I ordered XLR cables, will arrive next week.

 

[vddobrev]

You have a ground loop being introduced by your TV through the copper HDMI interconnect. It could be caused by your TV being on a different circuit from your AVP/AMP, or it could be caused by something else connected to the TV. If you have a cable TV connection, that is a common source of problems.

The easiest fix is to switch all of your AVP/AMP interconnects to XLR.

Thanks for replying. The TV is connected to same power strip, but it is a 3 prong plug, while Anthems are 2 prong.
Nothing else connected to the TV, except the HDMI eARC and cable TV cable, which I rulled out, noise is there even when cable TV is unplugged.

 

[peng]

Thanks for replying. The TV is connected to same power strip, but it is a 3 prong plug, while Anthems are 2 prong.
Nothing else connected to the TV, except the HDMI eARC and cable TV cable, which I rulled out, noise is there even when cable TV is unplugged.

In my experience, the often mentioned two prong-three prong, connecting a ground wire to chassis of units together etc., kind of methods are hit and miss (I mean in some of those more complicated issues) because of multiple reasons related to how ground paths are still there regardless, so once you know it is truly a ground loop causing the hum/hiss, using balanced cables is the quickest way to solve the issue. Hopefully your XLR cables will fix it for you, most likely it will anyway.

 

[motogp34]

For calibration, would you use the stock mic or a UMIK-1 ?

 

[nathan]

For calibration, would you use the stock mic or a UMIK-1 ?

If you mean for ARC-G, I dont think the UMIK is recognized by Anthem Room Correction Genesis.

 

[Descartes]

For calibration, would you use the stock mic or a UMIK-1 ?

The reason they include a professional microphone is that it is tailored to their unit. So definitely use the one they provided

 

[motogp34]

Ok, no problem. I used the UMIK mic with Dirac before because it was better than the stock one.

 

[motogp34]

Is there an upgraded Mic or just the stock one ?

 

[Descartes]

Is there an upgraded Mic or just the stock one ?

The stock one

 

[Sal1950]

Is there an upgraded Mic or just the stock one ?

Mostly these mics don't need to be lab grade. They're most effective at measuring the very large response swings in the bass range
do to room modes and such and having the DRC software supply the best correction possible. Often these swings can be +/- 6dB or better.