How quiet is your Rogue Sphinx?

I have a new Rogue sphinx, I don't recall the unit I demoed to be especially noisy but I do find my unit to have some noise despite other owners describing the model as 'dead quiet'.

In both 'standby' and 'on' there is a quiet though audible hum coming from the right hand half of the unit (maybe I can hear it through the vent on the top). You need to put your ears pretty close to the unit though.

There is also a similar hum to be heard through the mid/bass unit, audible about 2 feet away. This is aside from the more common 'hiss' that is also present. Oddly if I turn my balance control left all the way, the hum becomes much louder through the right speaker only and can be heard about 10 feet away. If I turn the balance to the right the original hum in the left speaker actually decreases in volume!

I am used to speakers having a hiss but the question I ask is do any other sphinx owners notice this extra layer of hum/buzz that varies with the balance control in this way? Is your actual amplifier unit dead quiet or does it have a faint hum also?

Just trying to figure out if my unit operates typically or otherwise.

Thanks in advance.
I would suggest calling Rogue directly to discuss this. They are extremely customer focused and honest, and will do anything reasonably possible to address your concerns.
You indicate that you purchased this new. You should take it back to the dealer (if you bought it locally), and if the problem exists when the dealer hooks it up they need to address the issue. If it can't be duplicated, the dealer should be able to advise you so you can determine what system interaction is causing this.

Also, if you are comfortable doing this, power down the unit and remove the power cord, then remove and reseat all of the tubes. It may resolve or alleviate your problem.

As Bill_k suggested Rogue has great customer service, and you can call them too.
Well here we go...I will never purchase another Rogue product. I purchased a used Sphinx and it was probably the most regretful purchase I ever made. In Rogue's defense, I never gave it enough time to fully break in (I bought it fairly new). I also heard swooshing and popping sounds coming from the left channel. When changing the inputs from the front panel knob, the right channel completely cut out. I sent this back to Rogue where they assured me they fixed the problems and after that, could not duplicate them in their shop. I sold the integrated last week and the gentleman who purchased it HEARD EXACTLY THE SAME THING AS I DID. Wtf? How could that be? But gets better.....

Four times, FOUR TIMES when Rogue said they would call me back for updates, or returning my call, whatever, they failed to do so. In my audio experience, probably the worst customer service I ever had the displeasure of dealing with. I know other people have had better experiences, and that's great. Not this audiophile.
By the way, the gentleman who purchased my Rogue Sphinx had to send it back to Rogue less than one week after he got it.
I have been in contact with Rogue the last few days. Nick has been very fast with email responses and has told me that the Sphinx unit should have no noise. He suggested that interference on the AC line might be affecting the transformer but has said if it is shown to have an issue then they will look at it.

I will take it to the store I got it from and see how it compares to their floor unit. Rogue will give me a shipping label if there is an issue.

What alerted me to the hum initially was the fact I could hear it with the unit in standby mode, a little disconcerting.
So let me get this straight: any hum or hiss you hear becomes inaudible once the music starts playing? When you're actively/critically listening, can you discern a sonic deterioration because of the hiss/hum? If not, stop micro-managing and enjoy your Rogue.

You have one of the better tube integrated out there for its price. You're going to have SOME hum or hiss. Hell, my MLA Statement hybrid integrated (originally $11500) has some hum when it's on. Does it screw up the music?


Rogue is one of the most personable customer service entities out there. They'll help make things right as best they can.

It is quite true that the hum does not interfere with the music, my only issue is that if the unit is not operating as it should then I would definitely prefer to get that rectified, Rogue so far has been exceptionally helpful with emails answered within minutes sometimes.
I had a very similar issue. My Sphinx buzzed from the left speaker more loudly than the right, and when I turned the balance all the way to the left, the right speaker buzzed louder. I didn't keep the unit, and I've been hesitant to explore Rogue products since. To be fair, it was only one unit, but your experience gives me further pause.


Interesting that you seemed to have ha a similar issue too. Did your unit hum also? Did you have Rogue inspect that unit?
The hum coming from inside the amp is likely coming from the transformer. Noise or distortion on the AC line from light dimmers, small appliances, refrigerator can cause this. The only way to know in this case is to remove your amp from a shared AC line. Or it's possible that the factory transformer may be mounted in such a way that it produces noise; (a common occurrence). When playing your system, you don't hear the hum because the music is louder than the hum.

Transformer hum can not be heard thru the speakers. However, your balance control hum may be the same problem I experienced with my Perseus Magnum. After about a year of ownership, a hum developed thru the right speaker. When I panned the balance control left/right I could cause the hum to vary in volume.

I sent it to Rogue and it turned out to be a bad VC. It was replaced and no problems since then.
Thanks to all for suggestions and information. I will try the amp at a friends house to see if that changes anything as the first step to finding the issue.
I am a "humaphobe" and will not tolerate hum in hifi gear. I have 2 amps (tube and SS) plugged into a PS Audio Humbuster III (mostly for transformer hum in the SS amp...used rarely only for outdoor deck speakers), and my tube amp (Jolida jd502p) is extremely quiet can stick your ear on the tweeter and barely detect it's on. Any issues remotely like the ones described here would drive me nuts, so my sympathies.
From Simao: "Hell, my MLA Statement hybrid integrated (originally $11500) has some hum when it's on. Does it screw up the music?"

Ummmm.....yes, it does.

My Rogue had a hum so easily heard from the listening seat that it was actually distracting. Any amplifier I've had that had a hum was distracting. To me it's like listening to vinyl with all the clicks and pops....sorry, I don't want to spend my money listening to that.

Also, let me make another thing perfectly clear. In addition to the hum, the Rogue made "swooshing" and "popping" sounds from the left channel with or without music playing. There was obviously something defective with the amp. Not just transformer hum. I'm with Wolf. I detest ANY noise other than music coming from my speakers. It's way to distracting and removes me from the emotional connection.

I was at a friend of a friend's house about 15 minutes from my home about a month ago. He has a system that retails for somewhere just south of 300K. He played vinyl on his $30Kish 'table. Every album he played sounded like crap. Yes, garbage, because of all the pops. Way too distracting.

Who chose your screen name here?
So an update on the humming sphinx.

I took it to the audio store and compared it to their shop floor model, both units demonstrated the same unit hum and noise from the speakers. The conclusion by the store associate was that it was a bit noisier than he expected but hadn't especially noticed though I think he had noticed the hum from the left speaker was louder than that in the right. He felt the unit hum was the transformer but was a bit perplexed by the hum from the speakers especially how the hum increased on the right side when the balance was turned all the way left!

Anyway I will assume for now that the unit is operating to spec even if it a bit noisier than ideal, I have provided Rogue with the details, although it is interesting that Rogue felt the amp should have no noise but the two units examined do give off some noise.

Only if the balance control was turned entirely left would the hum be audible over quiet music at close listening, in practice I don't use the balance anyway so it is not an issue. Overall I feel the sphinx could be quieter but for me the noise does not affect the music, it is simply not loud enough. Maybe Rogue could change something in the amp to quiet things down a bit in the future. If I had been more aware of the noise upon initial demo I might have been persuaded to try quieter models but as it stands I like the amp so its good for now.
Big_katydid; Transformer hum does happen with some amps and you should try to find a device like the PS Audio Humbuster (which I believe is discontinued).

As for the volume control related hum, I would send this unit to Rogue for warranty repair. This very similar hum on my preamp was the result of a faulty part. Rogue does not make the volume or balance pots, they buy a batch of ALPS pots. They may tell you to swap out the tubes and clean the contacts and other troubleshooting tips, but in the end, this is their problem.

They are a very reasonable group of guys and they want their customers to be happy with their products, so they should have no issue with servicing the unit. If it was me, I would tell them this hum was unacceptable.
Yep, don't convince yourself the speaker hum is acceptable, as your pre should never have left the manufacturer exhibiting hum. Gear is just too expensive not to work perfectly, and that means no hum.

I had a transformer hum issue with one of my M180 amps. I sent the amp back to Rogue and they replaced the transformer. After that the amp was fine for the entire time I had that system.

Rogue said too that they'd apparently had some bad transformers make it into some amps. Regardless of whether the other amp in the store was noisy, I'd send the unit to Rogue for inspection or repair.
I've emailed Rogue again and as both units demonstrated the various noise I have asked if they think this warrants a return, I guess the ball is in their court so to speak, there is plainly an audible hum and the odd unequal hum from the speakers, if that is enough to convince Rogue their is an issue then so be it and I could send the unit to be checked/repaired, part of me does think that maybe that is just the design of the unit, admittedly that's not optimal but I'm currently not willing to start playing around with retail returns over something that doesn't actually affect my listening, I do however understand how some would not find it acceptable, $1500 is not crazy money but you still expect a quiet unit, there are plenty of cheap amps that are silent.
My final thoughts on the matter...the transformer hum seems to be in the design and it's not a deal breaker. You'll only hear it when the amp is idle and maybe not at all from your listening position.

However, no amp especially new and in spec should deliver hum thru the speakers. We know definitively that it is coming from the amp since you have repeated the problem when using the balance control. (I hope you have tested this by swapping cables).

I have read many threads regarding the Sphinx and nobody has ever mentioned hum and my suggestion is that instead of asking Rogue, you tell them you are sending it back for service. If you don't have the unit repaired, you will never in good faith be able to sell this amp if you decide to upgrade.

interesting that your two issues cover both of my units observations and both were repaired. (The testing was thorough, cables/speakers were switched, even different power cords used.

I'll see how Rogue responds next.

"Humbusters" are discontinued, but I found mine after searching around a bit so they're still out there. Great bit of kit as they say.
"I have a new Rogue sphinx, I don't recall the unit I demoed to be especially noisy but I do find my unit to have some noise despite other owners describing the model as 'dead quiet'."

It's a new unit. That's all that matters. Don't settle for less than a unit that is doing everything you expected. Rogue needs to make it right. You don't need to be buying devices to quiet it down. Transformer hum needs to be eliminated and noise through your speakers needs to be eliminated by Rogue or they need to replace your amp. This is my opinion of course. It's ultimately up to you.
I did ask Rogue if in their opinion the noise was an issue, Nick feels that the amp is working as it should saying that some transformer noise is possible and that some noise from the balance is normal.

I still have a three year warranty and unless there is a consensus from sphinx owners of a problem that is apparently fixable (say if somebody had the same issue and Rogue fixed it)then I'll currently accept the amp as it is, if the problem is noted later and is confirmed as fixable then I will look into it again.
Foster_9... "some noise from the balance is normal." Ridiculous statement, don't you think?

I've auditioned several preamps and an amp and the only noise I've ever heard was some hiss, and that came from the type of tubes being used.
I will be watching this with interest. I had been planning to get a Rogue Cronus Magnum direct from the company. Living in HI, I have no dealer and have been unable to hear the unit. I was going on rep and reviews. But the last thing I want to face are product and return issues it's too expensive and a hassle. I am now apprehensive over Rogue QC? I know that may not be fair but when I spend $2500 on some kit, I expect it to work as anticipated and represented. I want to know customer service will be supportive.
I'm glad I opened this thread at the very least it will make people aware of sphinx's noise and they can check it out for themselves specifically, it's the type of thing I wouldn't have thought of noting on a demo.

Regarding the hum you hear when you put your ear close to the amp, that may be normal. My Ayon Triton 1 has a very, very low hum that I can hear if I put my ear about six inches from the unit, but even then I have to listen closely. It is normal for that amp, so again, if you are hearing something like that then perhaps it is normal.

However, you also mention hearing a hum audible at 2 and 10 feet depending on the operation of the balance knob. That one I would have a difficult time accepting as normal. Again, if it were me I'd send the unit back.

With my M180s it was easy to ascertain that there was something wrong: one amp was quiet, the other had an audible hum that could be heard ten feet away. It wasn't a hum that was coming through the speakers, it was a hum coming from inside the amp itself. Concluding something was amiss was an easy call. I took the amp into the shop here, they called Rogue, returned the amp for repair, and that was all it was to it. As I mentioned before, we eventually got feedback that some bad transformers had made it into some amps so Rogue didn't really question the issue, they just took care of it immediately.

I would like to add too that when I had a Rogue system I always found them to have excellent customer service, from handling that transformer hum issue to replying promptly to my emails about tube compatibility. Though I have moved on with my system I still consider them a good brand and could only imagine they will give you an honest assessment if you get the amp back into their hands.

Regardless of how you choose to address the issue, I hope you end up enjoying your system.


Joekapahulu, you would be wise to. How is it that two regular guys like myself and the person I sold it to heard two different problems immediately but the pros who built the thing didn't after having it for five days? Thankfully Rogue is not charging him for the "second" repair however I do believe he had to eat the shipping cost to send it back. ????????? Really Rogue? Come on.

As you said Joe, that's something to think about considering where you live.
Very quit since I sent it back. I had it maybe a week and sent it back. To much noise with the volume pot which was audible through the speaker, same issues I had with Virtue M901(which I enjoyed alot more).
Foster_9... "some noise from the balance is normal." Ridiculous statement, don't you think?

Yes, Lowrider that is totally unacceptable, from a quality control perspective or any perspective.
Devilboy: so did the guy you sold the unit to actually get a repair?

I will give some feedback to my audio dealer (with the same noise in their unit) as to Rogue's response.

In this situation some people could insist on a return but to be honest the noise does not affect listening as it does not rise with volume increase. I think what bothers me is that there is some noise there and it's seemingly a tolerated part of the design which I think is sub optimal, in practice its not noticeable but the mere fact of its presence would bother many. In future I may just make sure that in any amp demos I actually get my ears up to the unit/speakers and play with the knobs a bit before I listen to anything playing!.....
I think that it a reasonable expectation to buy decent gear and not have it hum. I also think there is alot of gear out there that people accept with hum thinking thats the way it is (not necessarilly) and that the hum doesn't effect the music (it does; everything effects the sound); I don't think most of us understand "quiet" and "black background" until you really experience it. And, reviewers comment on "quiet" but they usually mean the sound of the music and not mechanical sounds. If reviewers commented on the mechanical sound as well, we'd have a nice little game changer.
Actually, as it is a very quiet morning I did test the amp, the hum does change a bit as you raise the volume (went to 12 oclock to simulate loud listening), however it is rises in the right channel and reduces in the left!

To be honest if my dealer asked me if I wanted to change gear I would consider it but they have a no return policy as they give home demos and as this is supposedly working to spec they might not accept that as a request. IT is a shame as the rogue sounds pretty good.
I think what is perplexing about the hum is just how asymmetric it is: turn the volume up and it rises (slightly) on the right, reduces on the left, if you then turn the balance to the left the hum becomes much louder on the right but unchanged at the left. The hum from the right speaker in that instance really is audible from several feet away but in practice I can think of no instance where I would listen to the left channel only.

Anyway something for potential sphinx buyers to test when they audition the model.
further to my last post, I have a rega brio in the TV room and the noise consists only of typical 'hiss', noticeable through the tweeter, little deeper in the mid unit and barely perceptible in the bass unit.

If I turn up the volume knob to maximum (no signal) there is no change that I can detect in the level of hiss and to the nature of the sound, it really does demonstrate to me how noisy the sphinx is, unacceptable by comparison.

the transformer hum you described in the perseus, did that give any noise through the speakers also? Or was it only the hum from the unit itself? I do wonder if my 'variable hum' is related to that which I hear from the unit.
I have a Rogue Cronus Magnum and have had it for years. It's been a perfect amplifier. I've been in contact with Rogue several times with questions and their customer service has been excellent. Devil boy's comments are the first negative comments I've ever read about Rogue anywhere.

I submitted a follow-up to my earlier note but it hasn't posted yet, so this reply may be redundant... we'll see which actually appears first.

A minor correction to your question, my amp was one of a pair of M180 mono blocks rather than a Perseus. The hum came only from inside the amp and was not transmitted to the speakers. The only sound coming through the speakers was the usual faint hiss from the tubes. Nothing unusual there. Once the faulty transformer was replaced both mono blocks performed flawlessly for the four years I owned them.

Going back to another of your posts, I wouldn't wait for the dealer to offer an exchange, I'd either tell them to get you a new one or handle returning yours to Rogue for inspection or repair. If they balk at that I'd call Mark O'Brien directly and tell him what's going on. But all of your posts describe an amplifier that I would not keep. They describe too, at least up to now, a dealer that I would be hesitant to keep too for that matter. Home demo or not, your dealer should work with you on getting this issue resolved. They may say that the unit is working to spec, but how do they know? Or get Mark O'Brien on the phone and ask him if this is up-to-spec performance standard. I've met Mark and visited with him for about an hour at a recent audio show. He proved himself to be committed to customer service when I owned a Rogue system and that feeling was only reinforced upon visiting with him. I told him that I had moved on from my Rogue system but wanted to take the opportunity to thank him for his support when I did own his products. I firmly believe that if you tell him that you are not happy with your amp, nor happy with the dealer representing him, he'll help you. Again, I would tell your dealer what you want done and if they don't help then go around them, and also lodge a complaint with Rogue about them while you're at it.

Good luck,

I'll agree with Donjr, the customer service response is excellent.

Mark O'Brien did email me this morning. He suggests that the grounding for tubes and class D to be tricky and that in different environments there may be noise at the balance. He reckons that any sphinx in my set up would do the same. Perhaps its not ideal but as long as my unit is operating to spec then I can be assured that at least at future upgrade I can say it's working to spec.

On the topic of rogue I did also home demo the cronus magnum but I found it quite mushy sounding compared to the sphinx, maybe I'm not destined to be a full tube fan. I was actually surprised just how much softer the cronus was compared to the sphinx, still it made a street harp players recording sound incredibly seductive instead of biting.....and it made thinner or bright recordings much more manageable, but overall I prefer the more 'direct' sound of the sphinx.

I think being so used to SS that I'm used to the extra detail, plus im not sure I'm ready for hot 60lb metal and glass in my house!!

Glad to see that Mark got back to you. If he figures your amp is operating properly according to its environment then that would be good enough for me too.

Regarding your comment about extra detail and solid state, all I can say is that I think you might be surprised at the amount of detail that a properly set up tube system could deliver.

Glad though that it seems like the concern with your amp can be put to rest!



The transformer hum is audible close up, certainly not several feet away as was yours. The balance hum is more the issue, to be honest if I tried for an exchange with the dealer they probably would oblige especially as they also felt it was a bit noisy. However I do like the amp and find my system engaging (I actually got the amp after suffering a nait 3's excessive gain in the line input for years, actually not as I was using an attenuator! I finally had enough, bought the sphinx and am now able to listen to cd).

I'll probably ask mark a few more questions after the weekend.
BTW, if the transformer hum turns out to be DC on the line, there is now the Humdinger from AVA, that does what the Humbuster does (reportedly even better). If DC on the line isn't your problem, then it won't help you. But they have a 30 day return policy
Man, I was contemplating buying a new Sphinx or a used Audio Research VSi-55 for slightly more money. I ended up going with the Audio Research. I feel like I dodged a bullet. The Audio Research is dead silent.
Got to hear the Sphinx and pharaoh yesterday. Liked them both very much. Both were a bit larger than I expected but we're a lot of quality product for the dollar. Am considering downsizing my second system to an integrated and the rogues checked all my boxes.
Mapman, no contest between the Pharaoh and the Sphinx. The Pharaoh measures up to Rogue's high-end gear. You won't hear any complaints about hum passing thru the balance control. lol.
Low I didn't have time to compare in detail including noise levels but both sounded quite good. Pharoah is 3X the price and a good bit larger so to be expected. My dealer who traditionally sells a lot of reasonably pricey tube gear indicated the Pharoah was his absolute favorite sounding amp, which is saying a lot. Pharoah would be a reasonable choice to downsize my main setup where I have lesser need to downsize currently. Sphinx would be for my second system in teh family room were I to pull the trigger. It would fit into my cabinet there and allow me to forgo the TAD Hibachi monoblocks sitting separately on the floor crrently. The possible noise issues reported would be my only concern. I may just stay on the bench for now. These things will only get better over time.
The Sphinx is an entry level model, so I wonder if Mark would do any mods to it. With the Magnum models he upgrades the caps, power supply and adds cardas wiring.
Food for thought.
A late follow through to this thread. I did unfortunately abandon the sphinx primarily because of the noise issue, I feel it is an otherwise competent unit but that level of noise was simply unacceptable, a sub $1000 NAD unit by comparison was practically silent. The sphinx comes in V.2 now and is described as having a lower noise floor, I wonder if this is a remedy to the hum/hiss of the original. I'd recommend the sphinx still but if an asymmetric hum/hiss concern you from speakers then I would check the level on the original version carefully.