Quote: I'll be posting the power tube reviews shortly, just waiting for the gold Russian tubes to arrive. =)  

Quote: Thank you for your kind words. Looking at their data sheets, the stock 6N6P tube draws 750mA compare to the 6H30Pi which draws 850mA heater current, which is not much of a difference. Empirically I never noticed a volume difference between the two (I'm using matched Novosibirsk...

Check out these 6J1 driver tube rolling reviews: http://www.head-fi.org/forum/thread/563884/little-dot-tube-amps-vacuum-tube-rolling-guide#post_7625993  

.

  5. CONCLUSION   5.1 Can’t Decide Which Tube to Buy?   To Little Dot’s credit, their Mk-series amps have an impressive number of tube rolling options and there are more than a few very informative threads dedicated to this topic.  I would recommend anybody interested in upgrading their...

  4. POWER TUBES   4.1 Overview   The power tubes reviewed in this guide only applies to the current production Mk series amps. Unlike their impressive flexibility with signal tubes, most current production Little Dot amps can only accept 6N6/6H6P power tubes with the exception of the...

  3. EF95 FAMILY   3.1 Overview   The EF95 family is the most versatile and widely available of the three families of tubes reviewed in this guide. I recommend beginning users to start tube rolling within this family because it has the most variety of manufacturers and models to choose...

  2. EF92 Family     2.1 Overview   The EF92 family tends towards a more neutral sound with an emphasis on great vocal presentation, but the sound quality can vary wildly between different manufacturers. This is the only family of driver tubes that can be used on the older (out of...

  1.EF91 FAMILY   1.1 Overview   Known for its linear and extended presentation in the top-end but sometimes suffering from ‘boombox’ bass, the EF91 family of signal tubes is a great choice for jazz aficionados looking for that crystal-clear treble and who prefer (or do not mind)...

Little Dot Tube Amps: Vacuum Tube Rolling Guide   A quick introduction: Who is this guide for? (plus some background)   When I purchased my first Little Dot amplifier in 2005 I was in a position many of you are in now.  I was new to high end headphones, and curious about the ‘tube’ sound...

Great episode. Kudos!

A quality alternative to the 6H30Pi -DR (which are incredibly expensive IMO) is the Electro Harmonix 6H30Pi Gold Pin. I've used them in my MkIII with good results, certainly much better sounding than the stock 6H6P.   - DoA

It was certainly the best amp Headroom made at the time. I was always struck by how enormous the enclosure for the amp is, it looks like a huge chunk of aluminum on your equipment rack.   - DoA

I used to have both the MS2i and the HD650, at the same time. Now I only have the HD650. So there. =)

You can do the 6H30Pi mod so you can use the much better power tubes on the MkIII.