[Andykong]

Hi Everybody. I just got one cayin HA-1A mkII since about 3 weeks. I think I've read all this thread before buying one^^

First gorgeous piece of gear <3

Some trouble of noise floor that I almost solved :
- something looking like white noise => by plugging the pre-out to something (luna eclipse help a little, cayin C5 helps a lot..)
- Noise coming from my computer through the USB of my dac (Xonar essence STU) => using toslink and remove the USB cable from the dac. (other usb dac same problem ex dragonfly black)

I've still some low noise lookings like ground loop that are quite audible with HD800s and getting higher when rising the gain knob. I've tried to use a Furman AC210 and it doesn't change anything. still listenable... But a bit anoying^^.

Next step find some great 12au7, because I find some part of the sound too recessed ^^

Nice work, tube amplifier is relatively more prone to interference than solid state amplifier. The first trick you did is to remove "open loop" which is a problem that you won't find in solid state amplifiers. I always thought the switching power supply of the PC is evil and USB cable is a lesser problem. Did you use standard USB cable from computer accessories shops? If that is the case, maybe a not-so-expansive aftermarket USB cable can also solve the problem. I am not recommending anything exotic, only something like the Super USB cable. In my experience, some DACs didn't implements appropriate filters to eliminate the noise transmit from the digital source (especially computers), a well constructed USB cable with "One twisted pair for data and one twisted pair for power, individual screens for minimal interference" structure might solve the problem.

I agree with @Pictograms that the trouble shooting guide from PS Audio is one of the best publicly available tool to deal with ground hum, I have recommended that to several HA-1Amk2 and HA-300 customers having similar problems. Maybe you can start with a cheater plug, once you have confirmed the problem, you'll have a better idea on what should be done.

 

[Andykong]

We would like to thank all our friends, customers and partners for your continuous support throughout the year. We shall take a short break to reunion with our family and celebrate the Chinese New Year. We shall resume office on 14th February 2019.

 

[Orang_sabar]

Hi Everybody. I just got one cayin HA-1A mkII since about 3 weeks. I think I've read all this thread before buying one^^

First gorgeous piece of gear <3

Some trouble of noise floor that I almost solved :
- something looking like white noise => by plugging the pre-out to something (luna eclipse help a little, cayin C5 helps a lot..)
- Noise coming from my computer through the USB of my dac (Xonar essence STU) => using toslink and remove the USB cable from the dac. (other usb dac same problem ex dragonfly black)

I've still some low noise lookings like ground loop that are quite audible with HD800s and getting higher when rising the gain knob. I've tried to use a Furman AC210 and it doesn't change anything. still listenable... But a bit anoying^^.

Next step find some great 12au7, because I find some part of the sound too recessed ^^

I think it is electrical grounding issue. I used to have that issue in my audio setup. I just contact electrical services to add grounding cable to my home electrical system. Then the issue was solved.

 

[noobchu]

Hi everybody , thanks for all your advise.

I've already read the psaudio trouble shooting guide. I'm french and there is no Hum X equivalent here^^ or I didn't find it. I'll try to fix it later, it's ok to listen to with the knob set on low gain.

I've a last question : Is it important to change the 2 12au7 at the same time with matched pair tube ?

I Mean it's V1 and V2, I can just first change the V1 which is the most significant in the sound characteristic ? no ?

or the right channel went in one of the tube and the left in the other. ^^

 

[TylersEclectic]

Hi everybody , thanks for all your advise.

I've already read the psaudio trouble shooting guide. I'm french and there is no Hum X equivalent here^^ or I didn't find it. I'll try to fix it later, it's ok to listen to with the knob set on low gain.

I've a last question : Is it important to change the 2 12au7 at the same time with matched pair tube ?

I Mean it's V1 and V2, I can just first change the V1 which is the most significant in the sound characteristic ? no ?

or the right channel went in one of the tube and the left in the other. ^^

I had an issue with ground hum and narrowed it down to the RGB LED lights in my keyboard. I turn those off and don't have any issue. But it was a pain figuring out what was causing it... started by unplugging every device from my MacMini(2018) one at a time excluding the DAC, then once determined it was the keyboard randomly turned off the LED lights and voila, no more hum...outside of new tube hum...which I'm hoping will go away soon...or I may have to pick up some more tubes.

 

[TylersEclectic]

Been really enjoying this amp! I just need to get the tubes right, will be ordering more tubes soon. Currently have all Tungsol tubes in all positions. Also the HD820 were on loan and not mine. They are a fun listen though.

 

[jasonho]

@Andykong

How does kennerton Odin sound when paired up with this amp?

Do you have any reseller in sg carrying this?

 

[UsoppNoKami]

Just sharing:

Schiit Freya preamp with:
2x Tung Sol VT231 BGRP gain stage
2x Mullard ECC33 output stage

Cayin HA-1A mk2 amp with:
2x 12au7 Telefunken (smooth plates)
2x EL84 amperex bugle boy treble clef
1x RCA 13DT5 rectifier

Beautiful warm, airy and detailed sound with deep, solid bass on the Focal Elex, Quad ERA-1, Hifiman HE-560, Arya, HE-6SE and HE1000SE.

 

[TylersEclectic]

Just sharing:

Schiit Freya preamp with:
2x Tung Sol VT231 BGRP gain stage
2x Mullard ECC33 output stage

Cayin HA-1A mk2 amp with:
2x 12au7 Telefunken (smooth plates)
2x EL84 amperex bugle boy treble clef
1x RCA 13DT5 rectifier

Beautiful warm, airy and detailed sound with deep, solid bass on the Focal Elex, Quad ERA-1, Hifiman HE-560, Arya, HE-6SE and HE1000SE.

What adapters are in your Cayin for the 12au7s? And why? I'm relatively new to tubes so curious to learn more!

 

[UsoppNoKami]

What adapters are in your Cayin for the 12au7s? And why? I'm relatively new to tubes so curious to learn more!

They are socket savers

 

[TylersEclectic]

They are socket savers

Thank you! I'll have to look into those...

 

[mbphotox]

Using a tube amp myself (connected to my soundcard in the computer), I had some annoying sounds too. They could be eliminated by using a so-called DTI (dual transformer/isolator). http://artproaudio.com/product/dti-dual-transformer-isolator/
Just ordered a second unit because my home theater rig in the living room has the same issue with the studio speakers there.

Maybe this helps.


P.S.: If my Destiny Audio Aristaios mk II ever dies on me, I'll get the Cayin HA-1A.
Amazing piece of art that looks better than ANY headphone amp I have ever seen before.

 

[pichu]

Has anyone got to compare this to entry level Glenn, Feliks, Amps&Sound, etc tube amps? Thoughts?

 

[Pictograms]

Using a tube amp myself (connected to my soundcard in the computer), I had some annoying sounds too. They could be eliminated by using a so-called DTI (dual transformer/isolator). http://artproaudio.com/product/dti-dual-transformer-isolator/
Just ordered a second unit because my home theater rig in the living room has the same issue with the studio speakers there.

Maybe this helps.


P.S.: If my Destiny Audio Aristaios mk II ever dies on me, I'll get the Cayin HA-1A.
Amazing piece of art that looks better than ANY headphone amp I have ever seen before.

That ART isolator looks very cool, I may go and get one to try. I’ve used some other of there products in the past and they are great for the price.
What kind of sounds did it eliminate, I get various noise sometimes at different times in the day, I’m pretty sure it relates to my apartment neighbors... but who can be sure.

 

[Orang_sabar]

Hi all,

Today I made horrible mistake.
I accidentally plug the 12au7 tube in 12dt5 cayin ha1a mk2 tube socket, and I plug the 12dt5 in 12au7 socket.
Then the 12dt5 tube socket release electrical spark, smoke and burn smell.
Then i realize that I make mistake and switch back the tube.
Currently I don't hear sound problem.
But is it will be alright if I continue listen to the amp?
Do I make damage to my Cayin amp?


Thank you