It’s the time of year for saving money!
I wish I had a baseball cap that had the words “Hum Patrol” emblazoned on the front. I’d wear it any time I had to suss out a hum problem in one of my audio set-ups. Last week I would have worn it a lot.
The hum problem suddenly appeared one evening about twenty minutes into HGTV’s “House Hunters International.” My wife, Suzanne, turned to me and said, “What’s that noise?” That noise was a 120 hz hum. Next day was hum patrol day.
The symptoms were as follows: The hum was only present when the source was the Anthem AVM-20 pre/pro. The hum went away when the AVM-20 was powered down. The hum did not go away even when the AVM-20 had no source devices connected to it – nothing but the AC cord and the 7.1 analog outputs going to a Parasound P-7 multi-channel preamp.
I did all the standard stuff, like floaing the ground, reversing the plug, trying different power cords, and connecting a wire between the Parasound and Anthem to establish a common ground-plane. Nothing worked to reduce the hum, except turning the Anthem off. After what always seems like way too much time, I came to the conclusion that nothing I could do was going to solve hum problem. So, I chickened out and took the AVM-20 out of the system.
Downstairs at my test bench the AVM-20 was silent as a grave. No hum. Now, that is what I call a system incompatibility.My solution was to punt – I pulled out my longtime fave Meridian 561 pre/pro to take its place. What a lovely, understated piece of audio gear! And 561s are dirt-cheap these days on the used market. I see them go regularly for less than $300.
The Meridian 561 works beautifully as a Direct TV digital decoder. It recognizes all the standard digital codecs including DTS (not that I’ve ever heard of Direct TV using DTS – it’s pretty much a Dolby Digital, AC-3, THX world for Direct TV’s audio stream), and the Meridian 561 has all that covered. Also the Meridian is so quiet – to hear any noise at all I needed to turn it up too 100 (the highest volume possible) and all I got is a very low-level hiss.
The more time I spend with the Meridian 561, the less likely I am to go back to the Anthem. Not that a fully working Anthem wouldn’t be the Meridian’s sonic equal, but much of what the Anthem does I don’t need or use (such as a built-in FM tuner). The Meridian does just enough to be an outstanding Direct TV decoder (which was the Anthem’s primary function) without all the extra stuff. Factor in that I actually like the original Meridian MSR remote and you have a nearly ideal solution for that system.
If your primary video sources are Satellite or Cable TV and a Blu-Ray player, using the Meridian 561 as the audio interface for video could be an elegant low-cost solution for you as well. One word to the wise – don’t get the Meridian 565 instead of a 561. The 565 was one generation earlier in production (but at the end of its run it did have an option for 24-bit rather than 20-bit DACs) and lacks the input flexibility of the 561, but is priced about the same on the used market.
Just a note on this. I traced my hum problem to my preamp as well. Turn the preamp off or disconnect it and the hum goes away. Reconnect it, even with nothing connected, and the hum is back. Then I disconnected my cable TV and ran it through the filters on my power conditioner and every issue that I though was related to the preamp disappeared.