[Hikarii]

Hello everyone! I hope you are well.

I purchased this amplifier used, have demoed it at the person's house who sold it to me, they connected it in this way. HD800S -> Amp -> DAC (Chord Qutest) -> computer, which made it have zero noise whatsoever. Regardless of me changing the volume rapidly (which does create noise on my setup.)

Whenever I switch on my WA2 amplifier it seems to create lots of noise in form of 'hiss / electric noise' regardless of me not playing anything, even if I were to just plug in my headset without any output. Everything I've tried has not fixed the issue. I read that that OTL amps have an issue with constant noise. However, sometimes the noise goes dead silent and other times it gets louder than the music I play. (Not constant noise volume)

Currently connecting it this way.

Headset (primarily 1990 pro, hoping to use it on my Verite's) - > Amp > DAC (FIIO K11) *using optical cable and USB cable-> alternating between doesn't make a difference in noise* -> computer.

Things I've tried to eliminate noise:

- Isolating the power supply away from my computer. (still produces noise)

- Moving the entire amp away from the computer and into my laptop. (Still produces noise)

- Used multiple headsets of low and high impedance. (DT 1990, Audeze LCD2C *yes I am aware planars not the best idea for this amplifier*, among other headsets)

- Keeping all power supply cables into one extension cord from another wall.

- Turning off all lights, Bluetooth devices and mobile phones.

- Switching on the tubes and keeping them to warm up for 15-30 mins before playing anything on them and while are headphones connected (not sure if this makes a difference or not). (Manual stated one minute of warm is enough for it, still extended it for the sake of experimentation and no difference)

All attempts have not been fruitful, it has made little to no impact in terms of reducing/eliminating noise.

Everything I've tried was an amalgamation of many different 'solutions' others have tried in order to combat this 'problem' and I am out of options. If anyone has any idea what causes this it would surely drive away my current insanity from this noise.

Thank you for reading!

 

[jonathan c]

Have you cleaned the tube pins and the tube sockets? Have you tried other tubes? Is the output voltage of FIIO K11 too high for WA2?

 

[Hikarii]

I have tried the amplifier without the use of the FIIO K11 and the same result was found, seems that the FIIO after a while does stabilize the noise. I have not tried other tubes, I have purchased this unit two days ago and at their place it was great. No noise, no hiss. Which is why I found it weird that the second I took it home it had lots of noise, at first using my laptop without my computer being switched on reduced noise by a large margin. Though, second time I tried doing that has resulted in the same noise 'volume' as it does on my computer.

 

[tomb]

Tubes are, unfortunately, mechanical in structure and are susceptible to damage, especially when moved around. It can very easily be the tubes.

That said, you haven't really indicated any difference in noise from one channel to the other. Tube issues are rarely the same from one channel to the other, because a different tube is used for each (most of the time). If the noise is the same in both channels, then it is either your environment or a deficiency in your PC/source components.

Since you've used both optical and USB with the same issue resulting, I'd say your PC is not at fault. Either your FiiO is substandard in noise compared to the Chord and you never noticed it before, or the connecting cables (power or RCA) are not properly shielded and picking up noise (and you never noticed it before).

What kind of RCA cables are you using and are they markedly different from your seller's? Do you have a pair that are shielded you can try?

 

[Hikarii]

Hello Tomb, magically the distortion managed to eliminate itself. I thought it was due to the fact that the amp was on for a while (long operation = less reduction, that's how I imagined it). Though, switching off the amp as it has been on for eight hours meant that I'll put that to the test, lo and behold. It had zero noise, so I am not sure what has changed.

Two things I forgot to mention is that I am using a normal amazon RCA cable (RCA to RCA -> DAC to AMP) and that the DAC is brand new, as in just unboxed today. I wasn't aware that cables made a difference as lots call buying expensive 'cables' snake oil, which is why I thought the amazon one would grant no added benefit in comparison to an expensive cable.

From what I remember, I did glimpse the seller having a nice looking silver RCA cable. Oh and, they have supplied me with the same power cable they have used for the amplifier.

P.S: Noise was only made from the right driver, and it has been reincorporated yet again in small volume.

Kindest Regards,.