MHDT Havana owners.....question

Mine came with the GE JAN 5670W tube. I found it quite nice and relaxed. I then tried a Tung Sol 2C51 and it is much more precise and accurate. Not "tubey" at all. I recently bought some Russian 6N3PE (6H3NE) tubes for very cheap ($1.25 each) and they are my new fave. Wonderful detail, 3d sound, realistic. Really good.

What the Havana is sitting on is important to the sound. Try some different supports like firm and light vs cushion or inner tube. They all have different sounds.

Lastly, I also swapped out the dac chips for a better spec pair. Not expensive, but very worthwhile. This is a seriously good dac that competes well with my vinyl rig. Totally enjoyable to listen to for hours without fatigue.

I first read about those tubes from a guy on Head-Fi. In the big long thread on the Havana over there, he had this posting:

"But I want to tell you about a tube I just got in the mail a couple of days ago. I am listening to it at this very moment. First I AM Shocked!! I took out my bendix 2c51 and poped this in and I was not expecting much (for 3.00 for two tubes= 8.00 shipping=11.00 total) I can not believe my ears!!! This tube sounds every bit as good as the bendix(maybe better). I gave the other to my friend with one of these dacs so he can listen also. I expect the same response from him in his high end system when he gets back to me.
The Tube???---the Russian 6np3-e--- it is important that you get the E- model and not the other ones.( there is a 6n3p, a-6n3p-i, and a 6n3p-dr) I have only tried the E model. And I am not sure the other models would sound as good. At such a cheap price. I can't see why anyone would not at least try them. You should leave your dac on all night so the tube can cook some (improved bass). It seems to sound better after about 15 or 20 hours burn in. I understand that there may be some out there that disagree. But I feel that this is the bargin of the century for a tube for this DAC."

I got mine on eBay and there are quite a few sellers there. Cheap. Just do a search for 6N3P-E. They come in a box that is branded PAANO in Russian with the number 6H3NE on the box. All these different numbers are very confusing...