NEW Vali Schiit AMP!!!
Jan 12, 2014 at 11:19 PM Post #2,884 of 4,971
  Well, I just ordered HiFiMAN HE-400 
dt880smile.png
 So, more tests to come...
Thanks for sharing man!

Be careful about using a receiver. One thing is that they usually do not have a separate amp for the headphone jack but instead have resistors in series between the amp itself and the headphone jack. So one asks, why and is there a downside.
Most headphones cannot handle the enormous power levels that can come out of receivers/speaker amps. So to protect the headphones and not increase the cost of the product by incorporating a proper headphone amp, resistors are used to limit the power. The downside is that dynamic cans do not have a flat impedance curve. So a can that has an impedance peak in the bass will have a bass boost that one might think sounds good, but experienced ears will hear a less controlled bass due to the loss of damping resulting from that resistor. If you put those cans directly on the speaker taps and turn up the volume, you risk hurting your ears and smoking you cans. Orthodynamic cans like the HE-400's that you are getting tend to be resistive and have no such impedance curves and should not have issues with FR peaks or damping. Orthos tend to be less sensitive so many people will put them directly onto the speaker taps of a lower power amp like an Emotiva Mini. A Can like an HE-6 can take a lot of power, much more than the HE-400. I'd be very careful of putting any cans directly on the speaker taps of something that can deliver as much power as the Onkyo. You would have to learn about figuring out the proper L-PAD or T-PAD as appropriate to use with the exact combination of Amp and Cans. I have a pair of HE-500's hanging of my Vali and it works well, although not earsplitting loud, I believe your HE-400's will be more sensitive, hence louder.
 
Edit: I see more info was added to this thread as I was typing up this post.
 
Edit more: I just looked up the impedance curve for those cans and they are not too extreme. Still a simple series resistor is not the best approach and the value in the amp may not provide enough attenuation for a 250 Ohm can, so be careful with that volume knob. YMMV.
http://www.innerfidelity.com/images/BeyerdynamicDT880250ohm.pdf
 
Jan 12, 2014 at 11:31 PM Post #2,885 of 4,971
  Be careful about using a receiver. One thing is that they usually do not have a separate amp for the headphone jack but instead have resistors in series between the amp itself and the headphone jack. So one asks, why and is there a downside.
Most headphones cannot handle the enormous power levels that can come out of receivers/speaker amps. So to protect the headphones and not increase the cost of the product by incorporating a proper headphone amp, resistors are used to limit the power. The downside is that dynamic cans do not have a flat impedance curve. So a can that has an impedance peak in the bass will have a bass boost that one might think sounds good, but experienced ears will hear a less controlled bass due to the loss of damping resulting from that resistor. If you put those cans directly on the speaker taps and turn up the volume, you risk hurting your ears and smoking you cans. Orthodynamic cans like the HE-400's that you are getting tend to be resistive and have no such impedance curves and should not have issues with FR peaks or damping. Orthos tend to be less sensitive so many people will put them directly onto the speaker taps of a lower power amp like an Emotiva Mini. A Can like an HE-6 can take a lot of power, much more than the HE-400. I'd be very careful of putting any cans directly on the speaker taps of something that can deliver as much power as the Onkyo. You would have to learn about figuring out the proper L-PAD or T-PAD as appropriate to use with the exact combination of Amp and Cans. I have a pair of HE-500's hanging of my Vali and it works well, although not earsplitting loud, I believe your HE-400's will be more sensitive, hence louder.
Edit: I see more info was added to this thread as I was typing up this post.

Good post. Very helpful. Sounds like I'm going to need to stick with Vali after all that hype of mine :wink:
 
Jan 12, 2014 at 11:39 PM Post #2,886 of 4,971
  Good post. Very helpful. Sounds like I'm going to need to stick with Vali after all that hype of mine :wink:

One just needs to know what they're getting into as not to hurt ears or cans. Heck, you just bought an amp dedicated to driving cans. With the right information and twiddling it is possible to use a receiver with cans, but as we know you just bought a nice solution with the Vali. It's time for me to get a listening in 
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 before it's time to turn in.
 
Jan 13, 2014 at 12:02 AM Post #2,887 of 4,971
Anyone here experience a case where the vali started to ring w/o touching it? I have to unplug and re-plug in the headphone to get it to go away.
 
Jan 13, 2014 at 12:08 AM Post #2,888 of 4,971
  Anyone here experience a case where the vali started to ring w/o touching it? I have to unplug and re-plug in the headphone to get it to go away.

Yes, its very normal I think for the Vali to ring without touching it. For example: Put your headphones on whilst connected to the Vali and place your head near the amp. Talk from a normal tone all the way to yelling towards the amp. It will start ringing depending on how loud your voice is. This is micro-phonics from the tubes, completely normal.
 
Jan 13, 2014 at 12:12 AM Post #2,889 of 4,971
Really.. I have to do couple tests, maybe open it up to check if the tube is down and push it down.  Hopefully that would reduce the ringing.  If not I may have to send it back to Schiit, look like the newer releases have much less ringing according to the recent posts.  The price you pay for being early adopter :).
 
Jan 13, 2014 at 4:29 AM Post #2,890 of 4,971
Hi Guys,
According to micro-phonics issue you can do a simple mod.
Take some silicone tubing (like the ones used in medical stuff), cut the tubing in sizes of the vali tubes then cut them in length, so you can wrap them around the tubes.
Voila, no more ringing :)
 

 
 
 
 

 
Jan 13, 2014 at 7:19 AM Post #2,891 of 4,971
The tubes will always be microphonic and will always ring regardless what you do to them LOL Some tubes ring more than others, just the way it is.
 
Jan 13, 2014 at 9:08 AM Post #2,892 of 4,971
I emailed Schiit to see if they'd do a microphonics dampening kit. Curious to see their response.
 
Jan 13, 2014 at 9:31 AM Post #2,894 of 4,971
  Hi Guys,
According to micro-phonics issue you can do a simple mod.
Take some silicone tubing (like the ones used in medical stuff), cut the tubing in sizes of the vali tubes then cut them in length, so you can wrap them around the tubes.
Voila, no more ringing :)
 

 
 
 
 

 
Going on my experience using Blu-Tack....
 

 
... I like your idea of using silicon tubing, as it's a much cleaner way to add some mass to the tubes that might dampen the movement of the glass.
 
But... My Blu-Tack has only reduced the duration of ringing for any given stimulus - significantly - but it has not eliminated the ringing.
 
Problem:  The elements inside the glass tubes can still vibrate, no matter what you do to dampen the movement of the glass.
 
Jan 13, 2014 at 10:18 AM Post #2,895 of 4,971
Maybe in future versions schiit can add something around the tubes that will keep them from moving, instead of users doing that them self. Maybe like a plastic clip that re-moveable that keeps the tube from moving during use. Unless they change the whole tube layout to the tubes that stand straight up.  I do have interested in the vali but not if I have to manually find a way to make the ringer stop.
 

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