[tlarwa]

I just received my first ever tube amp, a Musical Paradise MP-301 Mk2.  Per the instructions, these are the tube types it takes:

V1 and V2 accept 6J8P, 6SJ7, 6SD7 and 5693 pre-amp tubes. V3 and V4 accept 6L6, KT66, 5881, EL34, 6CA7 and KT77 power tubes

To be honest, this means nothing to me.  I have no idea what the characteristics of different tubes are.  I listen to jazz, progressive jazz, singer-songwriter stuff, classic rock (Chicago, Elton John, Traffic, etc.).  No techno, speed metal, etc.  I'm driving a pair of Frugal Horns (very efficient).  The amp,has stock tubes now, which are (per the specs):

Tubes (Default)   6L6 (6P3P) x 2, 6J8P x 2

I'd like to pick up a spare/different pair of both the power and pre-amp tubes, and don't really want to spend a ton of money.  I'm open to hunting for NOS or used tubes if I can get the most bang for the buck that way.  I'd appreciate any suggestions on what to look for, and any tutorials on what the different tubes will provide in terms of sound (and the plusses/minuses of each).

Thanks for your help!

Tom

[FullRangeMan]

My 2 cents are:
EL34 is a very sweet sound tube and low power, it is not a powerful tube.
KT66 is a very linear tube.

[medium jim]

It appears that you currently have Russian 6L6's.  5881's are in the 6L6 family and are typically bottom end heavy, yet have shimmering highs. The EL34's are the same as the 6CA7's and are a very musical and sweet tube.  Some can be a bit pushed or forward in the mid's.

The KT77 is a slightly higher power EL34 and has similar characteristics. Based on what you listen to, the EL34's make sense.

Not at all familiar with the preamp tubes and would recommend buying a few sets of each to try or "Roll" to see what you like. 

In most cases the preamp tubes will have a greater effect in the overall tone and soundstage than the output tubes. 

Welcome to the tube world!

Jim

[tlarwa]

Thank you for the advice.  If I look for tubes, do I just go by the tube type designation (e.g. KT66, EL34, 6L6, etc.) and know that they will be compatible?  In other words, is there any other designation I need to look for that is more specific?  Just want to make sure I don't buy tubes that won't work with my amp.  Again, I am totally new to this!

[medium jim]

Personally, I would look for a matched set of Mullard  reissue EL34's.  A very musical tube, but natural and neutral.

Jim

[Ericus Rex]

There's a very long thread about tube rolling in this amp.  You'll have to google it.  I think it was over on headfi.org but I'm not sure.  Essentially, most people had problems with hum when they rolled the preamp tubes.  You may have to stick with the 6J8P.  It also can run quite hot so be sure it's ventilated well.

As for power tubes, I've used all the types you mention except the KT77 in my amp (not this particular brand).  My favorites are the Gold Lion KT66 reissue and the Siemens/RFT EL34 (this is the only EL34 I've really liked.  you can find them on ebay).  The 6CA7 'fat bottles' (true 6CA7s, not EL34s) sound quite good too.  Since this amp is auto biased, you'll have to buy matched pairs.

Another to consider is the russian 6L6 called the 6P3P.  I prefer the Gold Lions and Siemens over them but the 6P3P is good and cheap.

[jazzwave]

I have new one the MK 3 version, I rolled 2x 6L6 (stock, Shuguang) with Gold Lion re issue KT66, and 2x 6J8P(China stock)  with JAN Philips 6SJ7WGT...for this budget amp ,
Got some improvement, sound more open, quite silent no hum.