• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

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

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
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?
 
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. :)
 
Here's the tube's that I thought were compatible. Please correct me ..

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.
 
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).
 
Last edited:
Here's what low end tubes the amp has installed now

I have two 6N4 power tubes and one 6N14 driver tube.
Can I use this EL84: [FONT=arial, helvetica]Preferred Series 7189 (Premium EL84)
trans_1x1.gif

and this 12AX7:
[/FONT]
Tung-Sol 12AX7?
 
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.
 
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*EL84/6P14/6BQ5

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

The amp I have currently has a 6N4 and 2 6P14 tubes.
On this site : Russian and Chinese audio tubes

They clearly said the chinese 6P14 or russian 6P14P are equivalent to the 6BQ5 / EL84 ...

On those : 12AX7/6N4 China BEIJING!! and 12AX7 6N4P ECC83 China NOS Tube

They said the chinese 6N4 and 6N4P can be replace with a 12AX7 / ECC83 / ECC803 ...

But on this one : Tube audio 12AY7 Electro-Harmonix

They said the russian 6N4P is more like a 12AY7 ...

The 12AY7 have less noise but less gain than the 12AX7. Amplification factor of 40 VS 100 ...

Electro-Harmonix make very good tubes since a long time !

Cheers,

Alain. :)
 
Last edited:
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.