[Maxvla]

Quote:

Can't really say without knowing how much current the Valhalla can deliver. Just because it can swing 30 volts peak-to-peak doesn't mean it can deliver the appropriate current for a given load.
 
But assuming that it could (and doubt that it could nor would it need to into low impedance loads), here's what the 30 volts peak-to-peak translates into in RMS watts (W) and milliwatts (mW):
 
32 ohms: 3.5 W
100 ohms: 1.13 W
200 ohms: 563 mW
300 ohms: 375 mW
600 ohms: 188 mW
 
se
 

Thanks much Steve. I thought there might be some formula, which it appears there is. One other quick one, if you don't mind. I've always been perplexed as to why Little Dot lists it's MKVI power output at 120ohms (5W). Would you mind giving me 70V P-P outputs at 32, 70 (Hifiman HE-6) and 300 ohms? I've owned this amp for nearly 2 years and never really knew the power ratings at the impedances I actually use.
 
Thanks again,
 
Chris
 
ps. for your reference (page 5 and 6) Manual: http://dl.dropbox.com/u/6037680/Little%20Dot%20MK%20VI%2B%20Reference%20Guide.pdf

 

[volume]

I need some coparisons with Woo Audio WA6, also want to know what Grado's sound like with this tube amp.

 

[kingtz]

So...who wants to be the first to start tube rolling the Valhalla?

 
(I know they say it's not recommended, but surely it can't be absolutely impossible, right?)

 

[Steve Eddy]

 
Quote:

Thanks much Steve. I thought there might be some formula, which it appears there is. One other quick one, if you don't mind. I've always been perplexed as to why Little Dot lists it's MKVI power output at 120ohms (5W).

 
Couldn't tell you. Perhaps they feel it's a sort of middle range or something. Though interestingly, 120 ohms is the IHF spec for headphone amp output impedance. It's also possible that that represents the highest amount of current it can supply at that voltage swing, which would be just under 300 mA.
 
Quote:

Would you mind giving me 70V P-P outputs at 32, 70 (Hifiman HE-6) and 300 ohms? I've owned this amp for nearly 2 years and never really knew the power ratings at the impedances I actually use.

 
Sure.
 
32 ohms: 19 W
70 ohms: 8.75 W
300 ohms: 2 W
 
Of course in order to deliver the power above into 32 and 70 ohms it would have to be able to deliver 1 A and 500 mA respectively.
 
If we assume based on the 120 ohm figure that it can only deliver 292 mA, then those figures change to:
 
32 ohms: 1.4 W
70 ohms: 3 W
 
The 300 ohm figure would remain the same if it can only swing 70 volts peak-to-peak because that only represents 117 mA which is well below 292 mA and the power into 300 ohms is limited by voltage swing.
 
Again, this is only assuming it can deliver 292 mA so don't take it as Gospel.
 
se

 

[Maxvla]

Hm.. very cool. Thanks for indulging me

 
I had always for some reason thought 300ohms would be about 2W, but had no basis whatsoever. It was just a gut feeling.
 
I won't take it as gospel, promise!

 

[Steve Eddy]

 
Quote:

Hm.. very cool. Thanks for indulging me

 
I had always for some reason thought 300ohms would be about 2W, but had no basis whatsoever. It was just a gut feeling.
 
I won't take it as gospel, promise!

 
You're quite welcome. And thanks for the beer!
 
Quote:

I had always for some reason thought 300ohms would be about 2W, but had no basis whatsoever. It was just a gut feeling.

 
It's just some simple math is all.
 
Just take your peak-to-peak voltage and divide it by 2. That gives the peak voltage. Divide that by the headphone impedance. That gives you the peak current. Square that and multiply the headphone impedance by it. That gives you the peak power in watts. Divide that by two and that gives you the RMS power in watts.
 
se
 
 

 

[MashBill]

Mine shipped today and should arrive on the 8th!  I will be using it with AKG K702 and K701 cans, so I will post my impressions after proper break-in.
 
Bill

 

[baka1969]

Subscribed

 

[wgb113]

I'll have to dig out the white gloves that came with my Quad speakers.
 
One more day...

 

[Skylab]

Quote:

So...who wants to be the first to start tube rolling the Valhalla?

 
(I know they say it's not recommended, but surely it can't be absolutely impossible, right?)

Based on my recollection of the tubes being used (I tried to check, but their website is down), there is basically no tube rolling, due to the tubes used.

 

[Clayton SF]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif

Based on my recollection of the tubes being used (I tried to check, but their website is down), there is basically no tube rolling, due to the tubes used.

 
Yes, I read that as well. I was wondering what the 6N1P and 6N6P equivalents are and if the Valhalla can tolerate any tube other tubes than those.

 

[Clayton SF]

Quote:

I'll have to dig out the white gloves that came with my Quad speakers.
 
One more day...

...and then you'll have the whole 3-day weekend to enjoy your Valhalla;
...and white gloves; and maybe a microfiber cloth.
 
Without the tubes installed one is give a chance to peer effortlessly into its subterranean inner-werks. It's like coming across 4 vacant missile silos.

 

[Skylab]

There is no direct western equivalent of either tube.  If the amp is designed for the 6N1P, you can't use the 6DJ8/6922, as you will just burn them up.  And there is no close equivalent to the 6N6P - I think the 5687 is remotely close, but I can't find an English datasheet on the 6N6P.
 
In any case, the amp is designed for the tubes in it.  Rolling in this case is a bad idea.  Nothing to be gained other than trouble.

 

[Clayton SF]

Quote:

 
Is Valhalla your only headphone amplifier?

I wish I owned only one headphone amp but I own many others as well. I usually amp roll rather than tube roll.

 

[hodgjy]

 
Quote:

 I usually amp roll rather than tube roll.