Schiit Valhalla Tube Rolling thread.
Nov 25, 2016 at 8:44 AM Post #541 of 2,716
I got a pair of HD800 after the 800S came out and the price dropped. ATOMICBOB speaks highly of the HD650.

Aren't the Open Alpha headphones rather low impedance? I thought the Valhalla paired well with high impedance headphones that like large voltage swings? I do not wish to discourage you, experimentation is great fun, but they may pair better with your Vali 2.


I was Looking at the HD 600's and 650's, I really Liked the way they paired when I tried them at the Nashville meet. Still not out of the Question. I Bought a Pair of the Fostex TR series which is what the Alpha's are Based on and what I will use for the Project. I Really like the way the basic Fostex HP's out of the Box sounded with the Valhalla. They are not exactly efficient though.  I have them Plugged into my Vali 2 at work Right now. Yes, very Slow Day. If anything I will have a very Nice set Closed HP's for work.
 
Nov 28, 2016 at 2:45 PM Post #542 of 2,716
This has probably been discussed before but I have a question. I am considering getting socket savers for my Valhalla 2. How do you go about extracting the socket saver from the amp if you have an issue with them? It is hard enough getting tubes out when need be.
 
Nov 28, 2016 at 2:51 PM Post #543 of 2,716
Something like this:
 


Be careful though, otherwise:
BUZZ!!

 
 
Nov 29, 2016 at 7:12 PM Post #545 of 2,716
This has probably been discussed before but I have a question. I am considering getting socket savers for my Valhalla 2. How do you go about extracting the socket saver from the amp if you have an issue with them? It is hard enough getting tubes out when need be.


I've used a pair of hemostats (serrated jaws) with no problems.
 
Dec 1, 2016 at 12:16 AM Post #546 of 2,716
This has probably been discussed before but I have a question. I am considering getting socket savers for my Valhalla 2. How do you go about extracting the socket saver from the amp if you have an issue with them? It is hard enough getting tubes out when need be.


@Mediahound did sell "tube Puller/Pliers" (http://www.head-fi.org/t/781613/tube-puller-tool-pliers).
Tube rolling certainly has become much easier with them. I'm sure it will help with socket savers as well.
 
Either shoot him a PM or check ebay for something similar.
 
Dec 1, 2016 at 12:19 AM Post #547 of 2,716
 
@Mediahound did sell "tube Puller/Pliers" (http://www.head-fi.org/t/781613/tube-puller-tool-pliers).
Tube rolling certainly has become much easier with them. I'm sure it will help with socket savers as well.
 
Either shoot him a PM or check ebay for something similar.


Yeah, you can PM me. :)
 
Dec 3, 2016 at 2:49 AM Post #548 of 2,716
Hi all,
 
Just a heads up. I spoke to Nick at Schiit about possibilities for swapping the output tubes (6N6P) in the Valhalla 2. He said to be careful not to use tubes which exceed the heater current of the stock tubes (750mA).
 
In particular, this means you should NOT use 6N6P-I or 6N6P-IR (900mA), nor 6N30P or 6N30P-DR (850mA) - despite what the manual may say.
 
Dec 3, 2016 at 11:05 AM Post #549 of 2,716
  Hi all,
 
Just a heads up. I spoke to Nick at Schiit about possibilities for swapping the output tubes (6N6P) in the Valhalla 2. He said to be careful not to use tubes which exceed the heater current of the stock tubes (750mA).
 
In particular, this means you should NOT use 6N6P-I or 6N6P-IR (900mA), nor 6N30P or 6N30P-DR (850mA) - despite what the manual may say.

 
Does it affect only the lifetime of tubes or the interior parts of the amp. If only decreased the lifetime of tubes, that's ok since such tubes are not expensive.
 
Dec 3, 2016 at 4:02 PM Post #550 of 2,716
Does it affect only the lifetime of tubes or the interior parts of the amp. If only decreased the lifetime of tubes, that's ok since such tubes are not expensive.

Not just the tubes unfortunately. The windings on the transformer which power the tube heaters are rated for a certain current, so if you exceed that current the transformer may get hot, smell funny and eventually fail.
 
Dec 3, 2016 at 4:51 PM Post #551 of 2,716
Not just the tubes unfortunately. The windings on the transformer which power the tube heaters are rated for a certain current, so if you exceed that current the transformer may get hot, smell funny and eventually fail.


Ok, I see. Thanks.
Do you know the power of the transformers? Website says: Two internal power transformers with over 2,000uF of filter capacitance
But what I saw for other brand always give the power according to Walt.
 
Dec 3, 2016 at 7:09 PM Post #552 of 2,716
 
Ok, I see. Thanks.
Do you know the power of the transformers? Website says: Two internal power transformers with over 2,000uF of filter capacitance
But what I saw for other brand always give the power according to Walt.


The 2000uF indicates how much filtering there is on the power supply (to get a stable DC voltage from the AC line).
Some information at this link on the transformers:
 
"Because of our chosen tubes, the heater current is significant—about 3A—so it was best to treat it to a separate transformer. The heater transformer is the smaller of the two. The larger transformer is dedicated entirely to the HV supply, which along with almost 2.000uF of filter capacitance gives us a nice stable power supply with a lot of reserves."

 
The heater transformer provides 2.7A of current (2 x 6N1P at 600mA, 2 x 6N6P at 750mA) at 6.3V =~ 20W of power. To be safe in rolling tubes one should certainly keep the total current draw from all four tubes below 2.7A. But Nick suggests keeping the current draw of each tube below that of stock, which suggests that the input and output tube heaters are on separate transformer windings. In any case his advice is quite clear: do not exceed the heater current of the stock tubes when changing the output tubes.
 
Dec 3, 2016 at 7:33 PM Post #553 of 2,716
 
The 2000uF indicates how much filtering there is on the power supply (to filter out noise on the AC line).
Some information at this link on the transformers:
 
 
The heater transformer provides 2.7A of current (2 x 6N1P at 600mA, 2 x 6N6P at 750mA) at 6.3V =~ 20W of power. To be safe in rolling tubes one should certainly keep the total current draw from all four tubes below 2.7A. But Nick suggests keeping the current draw of each tube below that of stock, which suggests that the input and output tube heaters are on separate transformer windings. In any case his advice is quite clear: do not exceed the heater current of the stock tubes when changing the output tubes.

 
Thank you very much for the explanation!
 
Dec 3, 2016 at 11:37 PM Post #554 of 2,716
  Hi all,
 
Just a heads up. I spoke to Nick at Schiit about possibilities for swapping the output tubes (6N6P) in the Valhalla 2. He said to be careful not to use tubes which exceed the heater current of the stock tubes (750mA).
 
In particular, this means you should NOT use 6N6P-I or 6N6P-IR (900mA), nor 6N30P or 6N30P-DR (850mA) - despite what the manual may say.

So I bought tubes that are labeled 6N6P / 6H6PI .......are these okay ?
 
Dec 3, 2016 at 11:52 PM Post #555 of 2,716
Yes, there is a source of confusion there.
 
The stock Russian tube, which is OK, is called 6Н6П which can  be transliterated to 6N6P but also sometimes spelt out as 6H6n or 6H6Pi (since the last letter is a pi symbol).
On the other hand, there is also 6Н6П-И or 6Н6П-ИР which transliterates as 6N6P-I or 6N6P-IR - these are the ones to avoid which require extra heater current.
 
If you just check the Russian letters on the tube you should be able to see you have the right one.
 

Users who are viewing this thread

Back
Top