[sunneebear]

I just received an H10. It sounds really great with my Spirit Labs (Franken-Grado) 32 ohm phones. Very clear and dynamic.

One issue. It has some pretty pronounced transformer hum coming from the case.

The audio output is extremely clean/black with no hum but I can easily hear the case hum from several feet away.

Is this common with the Gustard?

Thanks!

Bad transformer or wrong voltage. Need to check it asap.

 

[olek]

  Glad to hear that it is not common.
 
Do you know the difference between major and minor surgery?
 
It's minor when someone else has it.
 
Thanks...

Love your joke, thanks!

 
As for humming, other than poor chap that received his 220V H10 actually configured for 120V (ouch), nobody else ever mentioned humming.
I know that mine was always quiet as a mouse - not a trace of vibration of any kind from it. I think you are likely going to have to deal with exchange. I know, it stinks.

 

[mandrake50]

  Love your joke, thanks!

 
As for humming, other than poor chap that received his 220V H10 actually configured for 120V (ouch), nobody else ever mentioned humming.
I know that mine was always quiet as a mouse - not a trace of vibration of any kind from it. I think you are likely going to have to deal with exchange. I know, it stinks.

I can't tell whether mine is turned on or not. Neither audible noise nor case vibration is evident. I just tried putting my ear directly on the top of the case... really, nothing. It surprised me, in fact.

 

[mourip]

  Love your joke, thanks!

 
As for humming, other than poor chap that received his 220V H10 actually configured for 120V (ouch), nobody else ever mentioned humming.
I know that mine was always quiet as a mouse - not a trace of vibration of any kind from it. I think you are likely going to have to deal with exchange. I know, it stinks.

Thanks for the helpful reply. I bought it used and so I am pretty sure it is set for the right voltage but I can check.

 

[tvnosaint]

Contact the seller.

 

[mourip]

Thanks. I did that first and am waiting to hear back.
 
Does anyone have Gustard customer support contact info?

 

[mourip]

I got in touch with Tina from SHENZHEN AUDIO. She is asking the factory about the issue. I told her that I bought the amp used but she is still helping me. Very nice service from them.
 
The seller said that he noticed the noise also but it did not bother him since the amp sounds so good.
 
I guess that the ball is in my court now. It is a wonderful sounding amp and a bargain at the $200 I paid so I may just live with the buzz. It is only a physical chassis buzz and the audio through the phones is silent.
 
Oh well...
 
Thanks to those who offered suggestions.

 

[ginetto61]

Hi ! a crazy DIY idea. Single new mains transformer outside the box, like some Schiit amps and this one.
 
http://img04.taobaocdn.com/bao/uploaded/i4/18102019350595033/T1.UQMXalgXXXXXXXX_!!0-item_pic.jpg
 
This will keep vibrations and emi far from the circuits. 
If you use a EI trype it will offer also better suppresion of the mains noise. 
I nice 60-100VA should be very good.
It is also a reversible mod.
Regards,  gino

 

[mourip]

  Hi ! a crazy DIY idea. Single new mains transformer outside the box, like some Schiit amps and this one.
 
http://img04.taobaocdn.com/bao/uploaded/i4/18102019350595033/T1.UQMXalgXXXXXXXX_!!0-item_pic.jpg
 
This will keep vibrations and emi far from the circuits. 
If you use a EI trype it will offer also better suppresion of the mains noise. 
I nice 60-100VA should be very good.
It is also a reversible mod.
Regards,  gino

 
Good idea. I have used outboard transformers in the past for DIY mods. I might try to add some dampening under the transformer casings first.
 
Oddly if I take the cover off most of the buzzing is gone. The cover must act as a sounding board for transmitting\increasing the vibration.

 

[ginetto61]

Good idea. I have used outboard transformers in the past for DIY mods. I might try to add some dampening under the transformer casings first.
Oddly if I take the cover off most of the buzzing is gone. The cover must act as a sounding board for transmitting\increasing the vibration.

 
Hi !  well then try: 

1. some weight on the cover to absorb its vibes.   
2. to decouple the cover from the chassis.  Or
3. to put some pads on the transformers.  I think they sell pads with one sticky side that you can cut of the shape you want. 

Good luck !
Bye, gino 

 

[mourip]

I put a Mapleshade brass weight on the chassis and it helped. Oddly when I first turned it on there was less buzz than yesterday. I am starting to think that my AC has a bit of DC in it...
 
Thanks for all of the suggestions. Sorry to divert the thread!

 

[swannie007]

"Dirty" AC circuits can create harmonics that can manifest themselves in odd, and sometimes destructive, ways. Perhaps this might be the case here. AC filters could help but may be expensive. If you can, take your amp to another location(friend/family) and plug it in there and see if it still vibrates. If it doesn't vibrate, then your AC supply is the problem, if it still vibrates then obviously your problem is elsewhere. Just m 2c worth. Cheers.

 

[olek]

   
Good idea. I have used outboard transformers in the past for DIY mods. I might try to add some dampening under the transformer casings first.
 
Oddly if I take the cover off most of the buzzing is gone. The cover must act as a sounding board for transmitting\increasing the vibration.

 
Try not tightening front/side screws all the way upon reassembly, leave them 1 or 2 turns loose.
I find that on my H10 last couple turns are causing slight bending of the casework that can cause, for example, volume control to bind a little. Leaving strategic screw or 2 a tiny bit loose fixes that (they are still under tension there and will not vibrate free).
 
Chances of this helping your problem are like, 10%, but hey, it is free and easy to try!

 

[mourip]

   
Try not tightening front/side screws all the way upon reassembly, leave them 1 or 2 turns loose.
I find that on my H10 last couple turns are causing slight bending of the casework that can cause, for example, volume control to bind a little. Leaving strategic screw or 2 a tiny bit loose fixes that (they are still under tension there and will not vibrate free).
 
Chances of this helping your problem are like, 10%, but hey, it is free and easy to try!

I like cheap and easy!
 
The brass weight has taken the buzz down to a very low level but I will also try the screws.
 
I am pretty sure that I have some DC om my mains and so will probably look in to some sort of filter. Evidently toroidal transformer are the most suseptible and the H10 has two. AVA makes something called a HumBuster. Might try that...

 

[willowbrook]

I have a thermal metal extension material that I have received from Burson, but unfortunately I've sold my H10. It is still wrapped in original wrap, unopened. If anyone wants them, shoot me a PM. Just pay for the shipping fee and Paypal (if you wish not to gift).