[helljudgement]

Just saw Auris Nirvana specs, It uses EL34 tubes which are not direct heated tubes (DHT), no wonder it has very low noise. For DHT tubes like 300B, Class A linear powered, it's almost impossible that you can eliminate noise/hum without sacrificing sound quality. CMIIW.

My 2c. I've tried quite a few headphone amps over the years. These are the ones I owned/tested more than once.

• DNA Stratus
• DNA Starlett
• WA2
• WA5
• WA6SE
• HA300 mki
• EC Studio B
• Schiit Vali

All amps are tested with hd800. ZMF Verite and a few planars are also used on some of these amps. The ones that exhibit noticeable noise are the Cayin and Vali.

I've tried two different HA300, both in show conditions, one quite a bit quieter the other exhibit a very noticeable amount of noise regardless of output impedance. Noise dropped significantly when using planar. The EC, DNA and Woo amps are dead silent regardless of gain and these are DHT.

 

[Palyodgree]

This time last year I had placed an order for one of Steve’s Dekerts Decware 300-B headphone amplifiers fully aware of the 12 month plus wait time , Two months into inline waiting a Cayin 300-B came up for sale used locally i was curious about . Waiting another 10 months I finally realized I couldn’t handle it so I popped over for a listen. He used the Cayin dual purpose as a headphone and speaker amplifier driving a pair of Klipsh RF-7 speakers . He also had a David Berning 1watt per channel amplifier I preferred driving those Klipsh speakers.

Headphones that he had on hand Sennhiser 600 , Foxtex 900 and Focal Utopia all three performered well none revealed any buzz or noise at all though using the Klipsh speakers a normal hiss was noticable at low to moderate gain with no music playing expected with such high efficiency .

Noise issue‘s today are so much more prevalent then decades ago , every wire and cable is an antenna, WiFi , RF the environment is saruated with it not to mention substandard building and home electrical issues like ground loops .

Hopefully the few here having issues with their Cayin 300-Bs can resolve them , it is a very good amplifier.

 

[mfgillia]

Edit :
Just saw Auris Nirvana specs, It uses EL34 tubes which are not direct heated tubes (DHT), no wonder it has very low noise. For DHT tubes like 300B, Class A linear powered, it's almost impossible that you can eliminate noise/hum without sacrificing sound quality. CMIIW.

Cheers

Just did a quick scan of the Auris Nirvana thread and did note some owners reported issues with noise and hum so I tend to think its not a 300B versus EL34 issue.
https://www.head-fi.org/threads/auris-nirvana-el34-amp-in-the-house.887621/page-4

From reading these threads over the years, it appears every popular tube amplifier produced commercially has had noise and hum issues plaguing at least some of their customers. I spent a great deal of time recently researching Ampsandsound products coming close to buying a Bigger Ben. Ultimately though, I decided against it primarily due to number of complaints related to noise and hum issues.

I did end up going with the Cayin HA-300 MKII after talking with Zach at ZMF and other happy owners who have had very positive experiences with their first and second generation HA-300s. Unfortunately, there does seem to be a certain amount of luck involved in buying a quality tube amplifier that will work well in one's home without suffering through excessive noise issues.

 

[linziyi]

BTW, on this hum issue, do we feel confident in assuming this has nothing to do with "DC offset"? Just curious.

What is the DC offset and how do I test it?

 

[ken6217]

The same could be said of those sensitive headphones.. should their manufacturers also state that they may hear humming with some amplifiers?

I think it is up to the responsibility of potential buyers to try equipment out before purchasing. Receiving a dud is another matter of course. We've been in this game long enough to know matching of audio gear is part of the process.

Come on. We're living in the real world. Tell me how most, if not all people are able to listen to equipment beforehand? Maybe if you're lucky enough to have a friend that has the component. the vast majority of components are purchased online through dealers.

It is incumbent upon the manufacturers to point out that sensitive headphones will hear a hum. And no, it is not normal for this to happen. I can buy hearing a hum externally from a transformer.

 

[ken6217]

I just tried my old Aeon Open @13 ohms. Dead quiet. I also swapped out my XLR cable for a 4.4mm headphone cable and there is still the hum. Not quite as loud, but still very evident.

 

[helljudgement]

I think it is up to the responsibility of potential buyers to try equipment out before purchasing. Receiving a dud is another matter of course. We've been in this game long enough to know matching of audio gear is part of the process.

Unfortunately that is often not up to us. Unless you're in a location where there's a lot of audio shop or know a hobbyist who have the specific gear you're interested in, chances are you're going in blind. In an ideal world for audio, everything we ever wanted will be there for us to trial to our heart's content but that's not how the the real world works.

 

[justanut]

No because competently designed amplifiers within sufficient parameters should not induce noise.

It's incumbent of the enthusiast to understand the context of operation. impedance matching, single ended topology, tubes especially DHT are inherently noisy, etc.
Whatever 2 o'clock means is important contextually. If you listen at 100dB nominal 120 peak, you are deaf, and are at the extreme threshold for noise.

If you're listening at 70dB nominal 85 peak, and noise is present, that is intrusive and a fault lies somewhere.

Agreed. You explain it better.

Come on. We're living in the real world. Tell me how most, if not all people are able to listen to equipment beforehand? Maybe if you're lucky enough to have a friend that has the component. the vast majority of components are purchased online through dealers.

It is incumbent upon the manufacturers to point out that sensitive headphones will hear a hum. And no, it is not normal for this to happen. I can buy hearing a hum externally from a transformer.

Also agreed that this is not normal and there is no evidence to suggest this is a design / manufacturing issue. I think what other owners like myself with no issues are doing, is to try and help pinpoint the problem if possible as this is a very bulky item to be sending back to dealers or worse, to China!

Unfortunately that is often not up to us. Unless you're in a location where there's a lot of audio shop or know a hobbyist who have the specific gear you're interested in, chances are you're going in blind. In an ideal world for audio, everything we ever wanted will be there for us to trial to our heart's content but that's not how the the real world works.

Yeah true as well.. just too used to Singapore with easy access. That's the risk with blind purchases, you've got to do so much research and keep fingers crossed.

 

[Erwinatm]

My 2c. I've tried quite a few headphone amps over the years. These are the ones I owned/tested more than once.

• DNA Stratus
• DNA Starlett
• WA2
• WA5
• WA6SE
• HA300 mki
• EC Studio B
• Schiit Vali

All amps are tested with hd800. ZMF Verite and a few planars are also used on some of these amps. The ones that exhibit noticeable noise are the Cayin and Vali.

I've tried two different HA300, both in show conditions, one quite a bit quieter the other exhibit a very noticeable amount of noise regardless of output impedance. Noise dropped significantly when using planar. The EC, DNA and Woo amps are dead silent regardless of gain and these are DHT.

I never tried EC and DNA, didn't have a chance to hear it in my country. I have listened to Woo WA5 1st gen with standard tubes a few years ago. I remember I could hear a little hiss with Grado though. Yes, it is more quiet than the HA300.

TBH, I prefer HA300 than WA5. Faster pace, tighter bass IMO.

 

[Erwinatm]

What is the DC offset and how do I test it?

DC current entering speakers instead of AC. It could damage drivers.

 

[Erwinatm]

Come on. We're living in the real world. Tell me how most, if not all people are able to listen to equipment beforehand? Maybe if you're lucky enough to have a friend that has the component. the vast majority of components are purchased online through dealers.

It is incumbent upon the manufacturers to point out that sensitive headphones will hear a hum. And no, it is not normal for this to happen. I can buy hearing a hum externally from a transformer.

Hum coming out from transformer most likely caused by bad transformer or electricity.

Again, for your case, I suggest you bring your amp to dealer or technician to be checked.

 

[Palyodgree]

Unfortunately that is often not up to us. Unless you're in a location where there's a lot of audio shop or know a hobbyist who have the specific gear you're interested in, chances are you're going in blind. In an ideal world for audio, everything we ever wanted will be there for us to trial to our heart's content but that's not how the the real world works.

Sure it’s not easy trying out components and wire before you buy , relying on chat forums and times over enthusiastic hype though some dealers are more then willing to lend components for home audition new and used floor models sent courier.
I belong to a group of nine other enthusiasts we lend each other some of our stuff to try out . Though there is only two of us that use headphones we both have a speaker based system also. Just recently I was able to home trial several different dacs and was able to directly compare the ones I liked best with each other . Belonging to this group has helped me get off the Merry go round , post a comment on your local audio forum and form a group , it’s great , new friends , different systems , music , drinks , good smoke it’s all good ..

 

[paradoxper]

BTW, on this hum issue, do we feel confident in assuming this has nothing to do with "DC offset"? Just curious.

Highly unlikely. Due to the nature of their transformers, they provide many advantages. Rolling out the rectifiers to ensure non-defect would be prudent steps before resorting to sending the amp out for service.

To be clear, those whom don't understand the tube nature and variability, don't get it.
The context of operational behavior matters.

There should be no present hum with adaptive impedance during a normal course of playback.

Extra is simply extraneous. If you'd like to criticize the circuit and topology for not implementing a better noise rejection, regulation, this is fair ground, you damn better be able understand these functions of principle.

A. Swap tubes in process of elimination
B. Check sources and double check assertion of noise
C. Pinpoint origin of noise through impedance switching (Most likely)
D. Isolate noise and address ground faults. (Most likely)
E. If all fails, then bitch more, rightfully.

You and @ken6217 should meet up to trouble shoot.
I feel Ken is too short tempered with complications due to compounding factors.

 

[ken6217]

Highly unlikely. Due to the nature of their transformers, they provide many advantages. Rolling out the rectifiers to ensure non-defect would be prudent steps before resorting to sending the amp out for service.

To be clear, those whom don't understand the tube nature and variability, don't get it.
The context of operational behavior matters.

There should be no present hum with adaptive impedance during a normal course of playback.

Extra is simply extraneous. If you'd like to criticize the circuit and topology for not implementing a better noise rejection, regulation, this is fair ground, you damn better be able understand these functions of principle.

A. Swap tubes in process of elimination
B. Check sources and double check assertion of noise
C. Pinpoint origin of noise through impedance switching (Most likely)
D. Isolate noise and address ground faults. (Most likely)
E. If all fails, then bitch more, rightfully.

You and @ken6217 should meet up to trouble shoot.
I feel Ken is too short tempered with complications due to compounding factors.

Who me???? I’m always short tempered. I have this crazy little defect in my personality where when I spend money I expect what I paid for.

Cory, btw I bought the VC African Blackwood. That’s the first home run I’ve hit in a long time. Absolutely incredible sounding. Definitely better than the lighter woods.

 

[paradoxper]

Who me???? I’m always short tempered. I have this crazy little defect in my personality where when I spend money I expect what I paid for.

Cory, btw I bought the VC African Blackwood. That’s the first home run I’ve hit in a long time. Absolutely incredible sounding. Definitely better than the lighter woods.

Your defect is unique.

I'm waiting for you to dwell back into the Abyss. Glad you're happy with VC. Still one of my favorites. I like monkeypod the most. Drooling over the Macassar.

But it'd be lovely to have your amp running as functionally designed.