I have an Anthem A5 and when I turn it on there is a slight "hum" if you put your ear close to it. From 3 feet away it’s unnoticeable. It's in the amp, not in the speakers. Is this normal?
After all this, my problem isn't a ground loop, bad ground, or anything external. Reading my email to the repair shop will explain; Hi Morris, Ok, I’ve exhausted my resources and have isolated the problem. I have a dedicated AC line I tapped from that powers my tankless water heater. This is a new line installed about 4 weeks ago and the water heater is the only thing powered by it so I ran an extension cord to the Anthem. The only connection after the Anthem is speakers. No input connections what so ever. The “hum” is in the amp AND audible through the speakers, all 5 channels. I still have my Integra DTR 50.3 and for giggles, unboxed it and connected it. Again, AC line into the Integra and speaker wires to the corresponding speaker. Result, DEAD QUIET! I went a step further and connected the Integra to the wall (not the dedicated line), same result. Another step further and connected the AC line to the Torus, Torus to the Integra, Oppo BDP-103 Blue Ray to the Integra, speakers connected. Again, DEAD QUIET!! My comparison is a $700.00 Integra AVR to a $4,000.00 Anthem amplifier. Conclusion; there is something going on internal to the Anthem. No question about it. It’s something common to all 5 channels. Lets review the chain of events…. When I lived in my condo, you serviced the Anthem and it worked beautifully! Had there been a “buzz”, I would have noticed. I’m POSITIVE of this! I moved to this house and upon installation, I found the Surround Right channel dead, so I brought it to you. Then technicians finding was everything was good. Considering the contradiction, you recommended the technician disassemble and reassemble the amp. Up to this time, I never heard a “hum” from the amp. Again, I would have noticed it. As soon as I got it home, connected everything, I heard the “hum” immediately and brought it back. You called me and said there were no problems and I took a leap of faith doubting my own observations. I’ve never heard a “hum” from an amp before. You stated all amps have a little bit of noise if you put your ear close enough. I wondered why I could hear it from my seating position. Were my ears that good? Possibly but, thats when I put my ear close to each and every speaker and discovered the same “hum” from the amp, I heard coming from each and every speaker. This is when I brought it back to your shop. In addition to the “hum”, the right side front panel ear was loose which got fixed. Immediately when I put it back in the system, the “hum” was apparent and I tried to describe it best I could. Again, doubting my own judgement, I gave it a day or so. I came to the realization that what I was hearing was not normal. It all became real to me today when I put the Integra in the system! To add icing on the cake, the technician neglected to install one of the housing screws and your office lady, had to mail it to me. It arrived today and I installed it. Morris, I’m at a loss on what to do at this point. It’s clear the amp is not functioning properly. A piece of gear of this caliber should be light years better than the Integra it replaced in my system, and it was, until the technician disassembled and re assembled its innards. I need to know how we are going to address this. I’m very upset and exhausted at this point and ready to send it to Anthem in Canada. Before I do, I need to know what you can offer for a solution. I know this will get resolved, the question being by who and at what cost. I’ve thrown a lot of $$ at this already. Thank you and I look forward to resolving this expeditiously.
Not likely to be DC on the line, but if you think it is, I have a PS Audio Humbuster I can sell you which did not solve my problem. For toroidial transformers, the mounting position is sensitive to hum, try rotating the right tranny around its axis for minimum hum, and the tightest position of the mounting nut may not be minimum hum. You can also order polymer washers from Herbies to better damp the hum, If the Anthem is 15 years old, it may also be the filter caps which may need to be replaced.
For those who have offered advice, education, and information, I am very thankful. I've tried everything almost imaginable to find the source of the "hum". I've deduced the problem to it's source being my original assumption. Doubting myself provided a lot of experience and I'm sure useful education for myself or someone else one day. I decided to send the amp to the factory where the technicians who will repair my amp work on only one brand, the one they specialize in, their own!
The shop did not reply to my email. I became more upset by the hour and decided to send it back to its creator who will surely find and fix the problem. Stay tuned as I will surely post again when my Anthem amp returns and is functional again.
Lesson to learn here; don't take a Ferrari to a Chevy mechanic!
The hum in my Prima Luna Prologue Premium integrated sounds like a constant 60hz. It is in both channels equally, Its amplitude is not affected by the volume control and muting the amp does not make it go away. My guess is that it's coming from the rectification circuit or some shielding did not get installed during manufacture. I bought it to power some 105db speakers. It is useless in this application.
The hum in my Prima Luna Prologue Premium integrated sounds like a constant 60hz. It is in both channels equally, Its amplitude is not affected by the volume control and muting the amp does not make it go away.
Now that sounds like a typical ground loop hum.
For the test below feed all the associated audio equipment from only one wall duplex receptacle outlet circuit. You can repeat the test later if you have more than one circuit you are using to feed your equipment and then check for hum again.
First disconnect all the source equipment from the inputs of the amp. With nothing connected to the inputs of the amp check for the hum. (I assume the amp uses a 3 wire grounded plug and power cord).
No hum?
Add/connect one piece of source equipment to the amp’s inputs. Check for hum. (In most cases the source equipment will use a 3 wire grounded plug and power cord that may be causing the ground loop hum).
Hum?
Disconnect that piece of source equipment from the amp’s inputs and then try another piece of source equipment and connect it to the amp’s inputs. Check for hum.
Hum?
If yes, good chance it is the integrated amp causing the ground loop hum problem.
If no hum, then it’s a good chance it is the first piece of source equipment you connected to the amp’s inputs.
Try all other pieces of source equipment and check for hum.
If no hum, then start reconnecting the source equipment, that did not cause the hum, back to the amp one piece at a time to the amp’s inputs checking for the hum.
If by chance you have a CATV cable box or a SAT dish box connected to the audio system in anyway start there first. Disconnect the incoming coax cable from the receiver box. This a prime suspect for a ground loop hum problem. What happens is there is a difference of potential, voltage, from the incoming coax cable shield and the safety equipment ground at the wall AC power outlet. In most cases the coax cable shield is not ground properly outside at the grounding block on the outside of the house.
I’ve worked with the national distributer trying most of what you suggest (cheater plugs, with source, without source etc.). The only thing I haven’t done is unplug everything in my house. I’d bet green money that the integrated is the source of the hum. My Balanced Audio Technology integrated is silent using the same electrical circuit. The noisy amp is under warranty. It works well with normal speakers so I may try to trade it in for some quite tubes or the new Pass Labs 25 watt SS amp. Thanks for your concern and advice.
@jea48 - It sounds most like your last link. Does the PL integrated have separate tubes per channel? Or could a single tube cause hum in both channels?
Is your system connected to a cable box or satalite dish via RCA interconnects? Sometimes the cable companies don't ground their outside connections to the home. This can cause a hum that will heard through the speakers.
No, my system is not connected to a cable box. I've given up wanting to use this amp with my Klipsch. Will trade in for a Pass Labs XA25 SS amp ( I tried selling here on A'Gon but couldn't get a decent price).
I had a similar issue with a very late model, one of the last few made, BAT VK 500 WBAT pack SS amp some years back.
One of the two amps within the chassis had a hum when initially energized. Noticeable. Easily. Within 10 to 15 mins the hum lessend and lessend to near inaudibility within an hour. If you got right on top of it after then you could hear an ever so slight humming.
An ancilliary ground loop made it more e exasberating. Fixing the ground loop did not fix the humming along T former in one of the two amps though. Calling BAT and talking with Victor K his input was something loosened up up inside the channels T former. Somehow. Somewhere.
Victor also said, ensure your gear is on the same phase.
I had several dedicated power lines by then. Still, it hummed.
The hum never intruded into the audio. There was a bit of hash one could hear if immediately next to one of the loudspekars, but a foot or two away and it too was inaudible. Bacon sizziling sort of sound. Grunge on the power line. Adding in some passive PCs helped… but once more did not entirely irriradicate the hum or hash at the squeakers tweeters.
Nothing seemed amiss during listening sessions. The presentation was exceptionally good. Outstanding in fact, and I was running the big VK500 single ended from my preamp… not balanced by then. Formerly, it was being run fully balanced yet still the hum was present then too.
So the proposition was to pay round trip shipping to BAT, or something then close to $180, or live with the humming T former.
As it was not affecting the audio, I kept it for a while longer.
It was then the best sounding rig I had owned. So, I sold it all off and began building another one exclusively with tube monos instead of SS power. Smart, huh?.
What I’m saying here is this…. Unless something is actually affecting the presentation, an outage, audible noise as with a ground loop, its gonna come down to just how pedantic one truly is about their outfit. If I could hear buzzes, or hums from my listening position, I’d have to get it fixed or get rid of it, if I could NOT hear anything from the LP, so what?
As its in an older home with an older home’s wiring there are tons of areas for electrical issues, provided it ain’t in the amp.
If you have hopefully a breaker box and not a fuse box, What I would try is: 1. Switching off every breaker except for the one (S) supplying power to the outfit. 2. have someone then switch each breaker back on and see if there is any change whatever as to hum from the amp, or noise at the speaker (s). 3. naturally, if with all breakers OFF and you still have hum in the amp, and or noise at the speakers with the volume dead low or mutted, then its time to send the amp off to Misassaugua NY and let Anthem check it out.
I’ve had to do that too with an Anthem Processor I owned some years back. They are great folks, but do keep in contact with them so everyone is on point during the assessment and or repairs, so it ain’t sent back with the same issue. My pre/pro came back with the same prob and had to go back again, but then better communication finally resolved the issue which was two fold on my end and one with the pre/pro. My TV provider, my home wiring and an firmware update or reconfig with the pre/pro.
Hopefully, your amp doesn’t weigh 140 pounds shipped.
Thank you blindjim, I’ve done every test I could come up with. The best isolation scheme was to only have the Anthem A5 connected to the speakers with no other component connected or plugged into house power. The hum was audible from the amp and coming through the speakers. The the Anthem was replaced with it’s predecessor, an Integra 50.3. With the Integra, no hum what so ever! why does a $4000.00 amp hum yet a "consumer" grade amp is dead quiet? the Anthem A5 is currently en route to Canada. I'll have a report in 2weeks or sooner. In the mean time, I'm having two 20 amp dedicated circuits installed so the amp will have plenty of power available.
***UPDATE*** Well, my Anthem A5 made it to its birthplace safely and today I had a conversation with one of the customer service reps. Sure enough, there WAS a problem. Replace a couple bad capacitors. I don't have the hard copy report yet but I'm glad they DID find a problem, confirming I wasn't imagining the "buzz", "hum", or whatever! As soon as I get the full report, I will list the problems here. Also, I located an Anthem P5 for a killer price that will be replacing this A5 so it will be going up for sale if the P5 checks out healthy upon arrival. STAY TUNED !.......
Just received the service report. All of the power supply capacitors (they look like long C-cell size batteries) needed replacing. It's like a new amplifier now. I understand the caps are what fails soonest in most cases. Funny thing, I just purchased an Anthem P5 that will probably replace this A5 and if so, will be up for sale....
***UPDATE*** My Anthem A5 will be here Friday but one caveat, just picked up my (new to me) Anthem P5 from UPS. OMG is it a BEAST! Holy crap, it's 130 lbs and just connected it up. This may not be the place for a review and I cannot articulate like the pros, just sharing my latest events. The Integra 50.3, my spare unit had to pacify me while the A5 was traveling from Los Angeles to Ontario Canada, it's birthplace. Sure it didn't sound anywhere as good as the A5 and as I yearned for it's return, fond this P5. Of all places, Craigslist. It came with 4 Audioquest Diamondback XLR cables. Why not 5 is a mystery. I'm not crazy about the Diamondbacks because they look like very early versions with choke type strain reliefs that clamp/screw together. In addition, a pair of Transparent Musicwave Super speaker cables, 12 ft length. These things are HUGE! Im curious to how they will sound compared to my Audioquest Type II speaker cables. I think I'll keep the Integra as a spare and put the A5 up for sale. I hate to since it's in near mint condition however, I'd say the P5 is a nice concession. Wouldn't you?
Just had my Levinson 23.5 serviced by an authorized Levinson repair center with many years of experience, capacitors were replaced not the big blue capacitors the medium smaller ones on the board 680UF 100V and other small transistors and resistors, there is no hum from the speakers at all, dead silent but when I opened the cover to look at the repair I place my ears on top of the amplifier I hear a slight hum you have to get really close to hear it. I assume it is normal maybe one day when I can afford a new amplifier I will have something to compare but I am happy with the Levinson 23.5 don't have any desire to replace except for a Levinson 33H.
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