[rnros]

In Vali2 I hear quiet background hum, irrespective of volume setting, with many headphones, with many tubes, on high gain. Low gain is always silent.
The tubes don't hum in other amps and I can't do much about the power supply so I try to use low power as much as possible.

I'll get back to you with more detail after I try some different combinations tomorrow. I have also noticed that some tubes have showed more noise in the Vali2 than other amps, including Lyr1, which also has AC heaters. On the other hand, I have noticed that some tubes lost some borderline noise after use in the Vali2. My sense is that these are borderline tubes to begin with. As for power, you can at least test going direct to the wall sockets in several different locations. There are other options also.

 

[HOWIE13]

I'll get back to you with more detail after I try some different combinations tomorrow. I have also noticed that some tubes have showed more noise in the Vali2 than other amps, including Lyr1, which also has AC heaters. On the other hand, I have noticed that some tubes lost some borderline noise after use in the Vali2. My sense is that these are borderline tubes to begin with. As for power, you can at least test going direct to the wall sockets in several different locations. There are other options also.

Thanks. I tried a few different locations but no joy. Sadly not possible to change the wall transformer as I think it's specially made for Vali2.

 

[rnros]

  Thanks. I tried a few different locations but no joy. Sadly not possible to change the wall transformer as I think it's specially made for Vali2.

Well, process of elimination... If it sounds the same straight into the wall in several locations, then it's not the power.
I don't bother with any power conditioners for the Vali2, only an isolation strip. I'll get back to you...

 

[HOWIE13]

 
Well, process of elimination... If it sounds the same straight into the wall in several locations, then it's not the power.
I don't bother with any power conditioners for the Vali2, only an isolation strip. I'll get back to you...

Thanks-I'll be interested in your findings.

 

[Magic77]

I recently purchased a VALI 2. I think it's great! I also own a Lyr-1. I made some comparisons between the two, and am liking the Vali 2 more right now. Does anyone else own a Lyr and a Vali 2?

 

[claud W]

I owned an original Lyr and rolled a bunch of NOS tubes in it, but I think my Vali 2 with 1974-75 Russian Reflectors or Voshkod sounds better. I do not have any hum or other extraneous noise with my Vali 2. I do have it plugged in to a Furman power conditioner, but it was inexpensive at $107 from Amazon. I think there is a pic of it earlier in this thread. I did have a motor boating sound at one point before I got the Furman, but moving the power cords around got rid of it.

 

[Magic77]

I owned an original Lyr and rolled a bunch of NOS tubes in it, but I think my Vali 2 with 1974-75 Russian Reflectors or Voshkod sounds better. I do not have any hum or other extraneous noise with my Vali 2. I do have it plugged in to a Furman power conditioner, but it was inexpensive at $107 from Amazon. I think there is a pic of it earlier in this thread. I did have a motor boating sound at one point before I got the Furman, but moving the power cords around got rid of it.

Yeah, the Vali 2 is really great. I was also going to get the Reflector 6922 from the tube store. They have them for $59.99 each. Not sure if that's a very good price. My original Lyr is sounding old I guess. Where did you get your Reflector tubes?

 

[claud W]

Got tubes on Ebay . They were shipped from the Ukraine. I would rather pay more from a reputable source like the Tube Store. 

 

[IPA-60-IBU]

I hope I'm not breaking any forum rules here, but I could sell you some of my russian tubes. 50$ for a tube is literally 25 times more than what I've paid for them...

 

[WayTooCrazy]

I paid $60 for my India BEL E88C I think it was.

I do like the more "tubey" sound vs stock, but the stock one makes the TH-X00 sound less syrupy.

 

[rnros]

  Thanks-I'll be interested in your findings.

@HOWIE13
OK, did some combination testing to the point that I absolutely convinced myself (at least), about the Vali2 and background noise or hum. Of course, this is related to the headphone impedance.
 
Short answer is that the Vali2 is very quiet, to the point of no perceptible background noise or hum, IF the tubes are quiet. This confirmed my previous opinion but I wanted to revisit the issue to be certain, sometimes we can learn to ignore a little bit of background noise if the overall sound performance is good.
 
Headphones used for test (impedance noted):
Senn HD600 (300 Ohm), AKG K7XX (62 Ohm), Oppo PM3 (26 Ohm), GR07 (IEM) (50 Ohm).
 
All four HPs were used with the same set of (quiet) tubes on the Vali2 and the Lyr1. After that series, the HD600 and the AKG K7XX were used for another sequence on only the Vali2, with an additional 8 tubes of various brand and type, all of which were quiet with the exception of one tube with a borderline noise/hum.
 
Level for each HP was set at a typical dynamic range of 50-80 decibels with peaks at 85-90. Vali2 was always set to high gain. Background noise was checked by cutting the signal at this volume level. To help determine if the background was absolutely quiet, after background level was noted, volume level was turned down to zero, and/or hi gain was switched to low gain, to see if there was any perceptible background change. (Of course, if you open the volume all the way, some low level hiss or hum will be heard, but this testing was to determine background at typical listening levels.)
 
Results: HD600 completely quiet, also the AKG K7XX surprisingly, given the low impedance of 62 Ohm. The Oppo PM3 with the very low impedance of 26 Ohm, showed just a very small level of background, in the category of 'very, very slight', or 'almost imperceptible', not a level that I would actually notice if I wasn't looking for it, or anything that takes away from it's performance. The GR07 IEM had a background level that was noticeable but still suitable for quality listening.
 
With regard to background noise, performance was fairly consistent between the Vali2 and the Lyr1. Again the Vali2 was tested at high gain, the Lyr1 has only high gain mode. With the Vali2 on low gain, everything is quiet.
 
If interested, I can list the tubes used but since all the quiet tubes gave the same result, I thought it was of secondary importance. So, (HOWIE13) there is a disconnect between my experience with the Vali2 and your experience. Not sure what the answer is. This test was using the Gumby to feed the Vali2, both were powered from an isolation strip into a wall socket used only for audio.
 
Last points: I do like the Vali2 for it's performance and convenience. I use it often to evaluate new tubes, since you can evaluate the triodes separately (one for each channel). So, I have a good bit of experience with it. However, IMHO, it is not up to the level of the Lyr1, or the other Schiit tube amps, but a very impressive little tube amp for $169.

 

[HOWIE13]

 
@HOWIE13
OK, did some combination testing to the point that I absolutely convinced myself (at least), about the Vali2 and background noise or hum. Of course, this is related to the headphone impedance.
 
Short answer is that the Vali2 is very quiet, to the point of no perceptible background noise or hum, IF the tubes are quiet. This confirmed my previous opinion but I wanted to revisit the issue to be certain, sometimes we can learn to ignore a little bit of background noise if the overall sound performance is good.
 
Headphones used for test (impedance noted):
Senn HD600 (300 Ohm), AKG K7XX (62 Ohm), Oppo PM3 (26 Ohm), GR07 (IEM) (50 Ohm).
 
All four HPs were used with the same set of (quiet) tubes on the Vali2 and the Lyr1. After that series, the HD600 and the AKG K7XX were used for another sequence on only the Vali2, with an additional 8 tubes of various brand and type, all of which were quiet with the exception of one tube with a borderline noise/hum.
 
Level for each HP was set at a typical dynamic range of 50-80 decibels with peaks at 85-90. Vali2 was always set to high gain. Background noise was checked by cutting the signal at this volume level. To help determine if the background was absolutely quiet, after background level was noted, volume level was turned down to zero, and/or hi gain was switched to low gain, to see if there was any perceptible background change. (Of course, if you open the volume all the way, some low level hiss or hum will be heard, but this testing was to determine background at typical listening levels.)
 
Results: HD600 completely quiet, also the AKG K7XX surprisingly, given the low impedance of 62 Ohm. The Oppo PM3 with the very low impedance of 26 Ohm, showed just a very small level of background, in the category of 'very, very slight', or 'almost imperceptible', not a level that I would actually notice if I wasn't looking for it, or anything that takes away from it's performance. The GR07 IEM had a background level that was noticeable but still suitable for quality listening.
 
With regard to background noise, performance was fairly consistent between the Vali2 and the Lyr1. Again the Vali2 was tested at high gain, the Lyr1 has only high gain mode. With the Vali2 on low gain, everything is quiet.
 
If interested, I can list the tubes used but since all the quiet tubes gave the same result, I thought it was of secondary importance. So, (HOWIE13) there is a disconnect between my experience with the Vali2 and your experience. Not sure what the answer is. This test was using the Gumby to feed the Vali2, both were powered from an isolation strip into a wall socket used only for audio.
 
Last points: I do like the Vali2 for it's performance and convenience. I use it often to evaluate new tubes, since you can evaluate the triodes separately (one for each channel). So, I have a good bit of experience with it. However, IMHO, it is not up to the level of the Lyr1, or the other Schiit tube amps, but a very impressive little tube amp for $169.

 
Thanks for doing such a comprehensive test. I would say about 10 of 15 of my tubes hum using the HD600 and 650 with high gain and can only assume either my amp is faulty or there is a mains problem. I don't however get such a consistent hum with any other amp so maybe it's the amp.
On the other hand I don't hear hum with my AKG702 and I do agree the amp sounds good when I don't hear the hum. Fortunately, I can usually manage to get adequate volume with low gain when there is no hum.

 

[rnros]

Glad it was helpful. Hard one to figure in your particular situation. Especially with the HD600, that HP is so, so quiet for me. Easy answer would be that 10 of the 15 tubes have some noise. Although that seems a very high percentage! However, if the other amps you are using have DC heaters maybe that explains the improved performance with the tubes in question.
 
Reason I'm questioning the possibility of the tubes being the culprit is that if it were the power or the amp, wouldn't the problem manifest with all the tubes to some degree?
 
The nine tubes I used represent six tube types, four are commonplace straight plug-ins, and two require an adapter. (Actually, the two types that require an adapter are more consistently quiet than the other four  types. I note that because I would always include any adapter in the list of suspects.) Tube types included 6DJ8, 6922, 7308, 6N23P, 6N3P-E, and WE396A. BTW, I did not include any of the 6N1P/6N5Ps (600mA heater filaments) in this test, but I have tried a number of these in the past and I have never had an issue with any of them in the Vali2.
 
Good luck, I hope you can find the source of the noise. Perhaps the tech folks at Schiit can offer some information or assistance?

 

[HOWIE13]

  Glad it was helpful. Hard one to figure in your particular situation. Especially with the HD600, that HP is so, so quiet for me. Easy answer would be that 10 of the 15 tubes have some noise. Although that seems a very high percentage! However, if the other amps you are using have DC heaters maybe that explains the improved performance with the tubes in question.
 
Reason I'm questioning the possibility of the tubes being the culprit is that if it were the power or the amp, wouldn't the problem manifest with all the tubes to some degree?
 
The nine tubes I used represent six tube types, four are commonplace straight plug-ins, and two require an adapter. (Actually, the two types that require an adapter are more consistently quiet than the other four  types. I note that because I would always include any adapter in the list of suspects.) Tube types included 6DJ8, 6922, 7308, 6N23P, 6N3P-E, and WE396A. BTW, I did not include any of the 6N1P/6N5Ps (600mA heater filaments) in this test, but I have tried a number of these in the past and I have never had an issue with any of them in the Vali2.
 
Good luck, I hope you can find the source of the noise. Perhaps the tech folks at Schiit can offer some information or assistance?

 
Thanks- I use Vali2 now mainly for listening in bed at low volume as it's so convenient to position on my bed table. I'm mostly using low gain anyway so hum not a problem at present.
Most of my tubes are 6DJ8 types and do sound very good in Vali 2. I thought about sending  the amp back to Schiit but Schiit UK appears to no longer exist and I don't want to send it abroad.
Cheers-appreciate all your input.

 

[Bleether]

Hey guys i've been out of the headphone game for a while now, but i just purchased the AKG K-712 and looking for an amp to pair specifically for these phones.
 
Is this amp good enough to drive it or do you recommend something else?
 
Did a lot of searching before posting, couldn't find a good answer for an amp for these phones.