what tubes should I upgrade a mini watt with I currently have the stock 6p14 and 6bq5

[jerrynsr]

Well I got my first WiFi tube amp. Its an APPJ. It has the stock tubes. What tubes do you recommend for an upgrade? For my initial test I have a pair of Realistic MINMUS 7 speakers I ran them with my old Magnavox amp that I salvaged from a console stereo when I was in college. They seemed to be efficient speakers back @ 1984. Should I go with El84 or something else ?
I will upgrade the 6p1 driver too. Should I go with 12ax7 or something else?

[Alain Poitras]

Originally Posted by jerrynsr

Well I got my first WiFi tube amp. Its an APPJ. It has the stock tubes. What tubes do you recommend for an upgrade? For my initial test I have a pair of Realistic MINMUS 7 speakers I ran them with my old Magnavox amp that I salvaged from a console stereo when I was in college. They seemed to be efficient speakers back @ 1984. Should I go with El84 or something else ?
I will upgrade the 6p1 driver too. Should I go with 12ax7 or something else?

You can't change the original tubes of your amplifier without modifying the circuit ... All tube are very different, you must use the good types but from a different brand if you like.

Cheers,

Alain.

[jerrynsr]

I was wondering what manufacturer of tube would sound best in this amp.

if 'm wrong I would like to know. I'm relatively knew at valve type amps.
I thought these tubes were compatible:

Power: 2*EL84/6N4/6BQ5

Driver: 1*12AX7/ECC83/ECC803/6P14



The amp I have currently has a 6N4 and 2 6P14 tubes.

[Bas Horneman]

What sounds best you have to determine for yourself.

A good starting point would be The 6P14P-ev as an EL84. And say something like the Tung Sol or Golden Lion 12ax7.

[Bas Horneman]

Power: 2*EL84/6N4/6BQ5

Driver: 1*12AX7/ECC83/ECC803/6P14

Should read:

Power: 2*EL84/6P14/6BQ5

Driver: 1*12AX7/ECC83/ECC803/6N4

[TheGimp]

It depends on which version of the MiniWatt you have. The earliest version is supposed to be the PA0803A with 6J1 and 6N1 tubes.

A later version had 6005 (6AQ5) output tubes, followed by the latest version with 6BQ5 and 12AX7 (PA0901A).

If you have the last version you can swap the tubes as mentioned.

The earlier versions are not compatible with the 6BQ5 (6P1P has a different pin out and 6005 is only 7 pin).

[jerrynsr]

I have two 6N4 power tubes and one 6N14 driver tube.
Can I use this EL84: Preferred Series 7189 (Premium EL84)
and this 12AX7:

Tung-Sol 12AX7?

[TheGimp]

Presuming that the 6N4 is the chinese version of the soviet 6N4P, and pins 4 and 5 are tied together with the other heater connection pin 9, then any 12AX7 or equivalent should work as the preamp/driver.

You should be able to substitute any 6BQ5/EL84 or equivalent for the output tubes. The only caviat is that some suppliers are calling tubes that are pin compatible EL84 or 6BQ5 and they are not voltage compatible (6P43P is an example of such a tube which can not be substituted).

Those 7189s are actually 6P14P-EV that have been tested to meet spec and should be fine.

The Tung-Sol should be fine as well.

[rvrazvan]

6p15p instead of 6p14p

[TheGimp]

NO! 6P15 has no internal connection between K and G3. You can destroy the tube if there is no jumper between these two pins on the socket.

An amp designed for 6P15p compatibility can run both. An amp designed for EL84 will most likely not have the jumper.