Loud pop/screech when powering on amp

Hello All,


I have an Audio Refinement Multi 5. I just bought her used in pristine condition a couple months ago. I get a loud pop when I turn it on. But the last couple of days there's almost like a weird screeching sound right after the pop . Everything sounds. fine when I play music/movies, but I'm a little concerned if this is a bad sign. I'm also a little concerned if this is harming my speaks. I have had other amps that pop and I know this is normal. I always turn her on last and turn her off first and volume is always low when powering on and off. I only use the power button in the front when done for the night. I have not turned the main power button off since connecting her. I have a Shunyata power cable plugged directly into the wall on the amp. I have an Audioquest Powerquest 303, should I maybe try plugging the amp into that, would that help? I also did turn off the main power switch on the back this morning and will try when I get home to see if this helps when I power her up...


Thanks in advance for any advice...


Best Regards...


Try the original power cord oriented per the manual -red dot on hot side of outlet.

Is there an option to enable soft or delayed start on the amplifier?

If it doesn’t run hot at idle I’d leave it on 24/7 (along with at least your preamp) until you get this sorted to minimize the possibility of damaging your speakers.  I’d go right to the source and call Audio Refinement directly.  Best of luck finding a solution. 

Sounds like a leaky cap.  Get it looked at before you blow your output stage transistors.

Thanks for the replies! @noromance i don’t recall seeing anything about red dot hot side? Do you think using the original power cable will help?

@soix the manual does recommend turning off the front power switch when finished because she does run warm. Maybe leaving it on though would better? My fear is speaker damage not so much the amp. 

@erik_squires i wouldn’t know where to get her looked at? It’s an older amp not manufactured anymore? Where could I even try to get someone qualified to give it a look? Any ideas? I live in NH…

Sorry my friend but I have no idea.  Call a local stereo shop, if you can find one.

thanks for the replies! @noromance i don’t recall seeing anything about red dot hot side? Do you think using the original power cable will help?

@kingbr , I am not sure if this is what noromance was referring to, but if the outlet is wired correctly, the narrow slot (to plug into) is the HOT one and the wide slot is NEUTRAL.


Thanks @immatthewj , so why would the original power cord make any difference do you think? 

Thanks @erik_squires, ya I guess that’s the best place to start local shop. 

So when I got home I flipped the main power switch in back on. Then the front power button. Still the pop but no after screech sound. I would describe this as something close to the sound of a quick drag of the needle across an album on a turntable. But again after switching off the back power switch this morning and turning her back on today no screech. Weirdly it almost seems like the pop only comes from my right front speaker. Not 100% sure so next time I’m going to listen to try and confirm that.

Maybe this is normal. My Earthquake Cinenova Grande does the pop thing and Joseph S said that’s completely normal. It was when the screech sound was added that I became concerned…

Thanks again All for helping. I got this amp for under 1K for my second system, so if I have to replace it it wouldn’t be the end of the world. However if she damages my SF Sonetto’s, now I got HUGE problems😬😳

Regarding the red dot, this is from the manual…

“For best sonic results, correct orientation of the AC plug is important. The prong with the red dot should be connected to the "hot" connection of your wall socket.”

Maybe it’s a Euro thing or something.  If you end up needing service maybe reach out to member bigkidz as I think he does repairs.  

Thanks so much @soix! Never saw this in the manual and never heard of this? But again the Shunyata cord plugs in the same way as the stock cord, no?

Any idea how I could contact bigkidz?

I think bigkidz is based in New Jersey, isn't he?  That would almost be in road trip range from New Hampshire.

Thanks @noromance and indeed @immatthewj NJ is road trip from NH😊!

@bigkidz if you’re available any chance you’d be interested in a 5 channel amp checkup/repair?



I agree with @erik_squires  that is possibly a leaky cap and it should be looked at ASAP before DC damage to the unit or even speakers occurs. My experience has been progressive deterioration starting with some noticeable distortion to a pop during turning off and on, or intermittent during playing.   You state it is an older unit.  If it has never been recapped that is my best guest.  You can try The Service Department in CT.  They service many out of production high end electronics. However, your brand is not listed, they are pricey, and it may not be cost effective to use them.  In addition, their turnaround time is long since their flight pattern is full. They do excellent work.  I used them for recapping Krells before I traded them in.  They use higher quality parts than Krell and there was some improvement in SQ after they serviced them   

30 Unquowa Hill St.
Bridgeport CT.

I used Steve at theservicedepartment to recap and fix a recall issue on an older Krell KAV 250 AMP.  He did a great job and is a super nice guy. The only thing is that he has a long wait list. And you'll probably pay at least what you spent on your amp for a recap/refurbish.

@kingbr  , is the "pop" you are getting  being heard through both speakers, or only on one side?

+1 on the leaky capacitor.   I had the same problem on an old USA Antique Sound Labs 845 tube amp.   The culprit was one of the capacitors, but I don’t recall which one.   I just had them change all of them out.   Then I sold that amp, not because of the squeal/pop, but just because I was moving on to another stage in my gear.

. . . well, if it is a cap, you could probably replace it yourself, and it probably wouldn't be a real hard DIY.  You could get an affordable cap checker on Amazon and then you could take the bottom (or top) off of your unit and check all the caps against each other (assuming that there are at least two of each).  Then if you find one measuring wildly different than the other one, you could get a replacement from PCX (Parts Connection).  I only suggest this because if I was able to do it, probably almost anyone could.

@immatthewj it seems only 1 side. Appreciate the info on the capacitor, gotta tell ya opening and going inside anything electronic is WAY above my paygrade😳. I did try AR’s website (I honestly didn’t think they were still in business) and sent an email last night, so I’ll see if they reply and what they suggest…

Question though, with a leaky capacitor would the amp still play and sound fine? Because it does there’s no static or anything?

A 'pop' is a DC offset (try hooking a flashlight battery across a speaker to get the idea). A 'screech' is a decaying oscillation. While some amps pop on startup, if it is only in one channel that's not associated with healthy electronics, and the screech is a more serious and imminent problem. You need to get your amp serviced ASAP or risk not only a more severe amp problem, but damaging one or both of your speakers. As others have mentioned most decent shops have extended wait times, so you ma want to find a temporary replacement amp on your local C-List. 

@kingbr - I can take a look but I do not have an interest in buying one  LOL

@noromance - PM me  Or look through other posts and you will find my business name  then google that for contact info

Thanks All! Love the comic relief😂! Can’t help it have always referred to my fear as she😂

Thanks @bigkidz. I’m waiting on a response from AR. I may just cut my losses and try to find another 1Kish 5 channel. The screech has not come back yet😬. It’s a second system so no great sense of urgency other than protecting my SF’s..

Thanks @panzrwagn! I’m looking around the C list now…am I doing damage by playing it? Everything sounds fine while it’s playing? Maybe just leave it on for now rather than power off?

I have had cases where I bought used and device worked for a short time then developed issues. I would not be surprised that owners are inclined to sell at first sign of a problem before it has a chance to fully develop. You just never know buying used directly. Which is why it is always a good ideas to be sure to have some form of suitable recourse if a problem develops after buying used, especially for big ticket items. It may or may not be the case here. Just saying....

Another recent thread asked about "disciplined audiophiles" .  Being disciplined is always a good idea when buying big ticket items either new or used.

Thanks @larry5729 ​​​​@mapman. I just reached out to the guy I bought it from (bought it here). He was really great so I’d like to believe he’s better than that and didn’t try to offload it…I’ll see if he responds. It’s my second system and I paid under 1K, so though that’s a lot of money, it’s not the end of the world. And I can always fall back on the Outlaw 550 for just over $800 with shipping🤷🏼‍♂️.

Waiting to hear back from AR (emailed and called but was on hold for 20+minutes with interludes of music and a recorder woman’s voice speaking French🤦🏼‍♂️🔫😂)


Let caps drain for a few minutes after you unplug the amp but before you open it. 

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Let caps drain for a few minutes after you unplug the amp but before you open it.

Actually, what the tech from Cary Audio told me many moons ago was that the caps would discharge faster if you left it plugged in (for a while) after you turned it off. But if one was really going to work on it, a shunt to manually discharge caps would be a good idea.

I’m waiting on a response from AR. I may just cut my losses and try to find another 1Kish 5 channel.

If you decide to cut losses you should jump on this — excellent amp at a very attractive price…

I believe the amp is > 10 years. As for opening and trying to diagnose/repair myself, this is most definitely WAY over my pay grade. Again weird thing is it’s playing and sounding fine. Would it do that if it had issues???


@soix I actually saw that McCormack on Audiomart. However that one is up there in age as well, no? And seller has it rated 7/10. A little hesitant but that one is definitely on my list. Think that’s a solid amp?

I actually saw that McCormack on Audiomart. However that one is up there in age as well, no? And seller has it rated 7/10. A little hesitant but that one is definitely on my list. Think that’s a solid amp?

McCormack amps are very solid and reliable, and I’d be surprised if you didn’t get at least another 10 trouble-free years out of it. Plus, SMcAudio is available to consult with and do repairs in the unlikely event anything happens. The amp looks to be in very good shape, and personally I wouldn’t hesitate to buy it if it’s not viable to fix your amp.  It’s a steal at the asking price IMHO.

if it is a blown cap, why would the amp still play and sound fine?

Sorry, OP; I don't know enough about electrical theory and function to answer that--I only know how to change parts assuming I can identify the correct ones.

I will say that I had an old preamp that was spitting and popping (but it did play) and I was talking to the tech at Cary about it (this was back when they would talk to you on the phone) and he actually did mention the possibility of a cap being bad.  So I guess it is possible that a cap could be on the way out but not completely gone?  I don't know for sure on that, and in the case of that preamp I just alluded to, it was actually some ancient worn out tubes.

@kingbr -- I hope you find out the issue, but if I were in your shoes, I would NOT continue to risk my SF Sonetto's.  For goodness sakes, disconnect those speakers ASAP.  If you want to continue to experiment with possible issues, connect the cheapest pieces of crap you can buy tomorrow off of Craigslist.  I've seen permanent damage done to high end speakers due to an ongoing sudden "pop" from the amp.  It baffles me that some brands accept a "power on pop" as normal or OK.  I'm not an electrical engineer expert or speaker driver manufacturer, but that sudden "pop" can't be good...it just can't.  Just my two cents worth.  Keep us updated!


Fidelis Audio is in Nashua and is an excellent bricks and mortar audio store.  For a small processing fee they will pass the amp along for repair to Jim Fuller whose shop is Fuller Sound out of Waltham, MA.

I just used Jim to update the caps on my speakers and am quite happy with the upgrade.  But it's an old amp and cost may or may not be prohibitive.

Thanks so much for all the thoughtful replies!

@jetter I have bought from Fidelis Nice to know they can assist. To your point might be cost prohibitive.

@soix Thank you for the details on the McCormack. So tempted on that. I reached out to the seller to ask how old and if he’s the original owner…

So many things to think about??? And again maybe this is normal?? Joseph S of Earthquake flat out stated there will be a pop on startup. Still nothing from AR which is now Focal/Naim I guess. Stay put, have someone look at the AR, McCormack, or Outlaw???🤦🏼‍♂️🤷🏼‍♂️