Best sounding tube for low power?

[Kashtan]

Amplifier for headphones. A lot of time I devoted to studying the question - which valves are best for sound from low-power. I found next 2 favorits: PX4 Marconi-Osram 1 generation with barium anode (1920s) Sonatron 71a (171-A). Any body hear this tubes? Are there any better ones? Thanks. Best wishes.

 

[JonSnell Electronic]

The first thing you must do is decide what parameters you require as that alone determines the amount of distortion produced by the choice of valve.
The size of valve, anode area/cathode material determines the amount of power that can be produced and other parameters.
So, there is no best sounding valve.

 

[Norelco]

1626
Kenzie - ampsandsound

 

[Kashtan]

The first thing you must do is decide what parameters you require as that alone determines the amount of distortion produced by the choice of valve.
The size of valve, anode area/cathode material determines the amount of power that can be produced and other parameters.
So, there is no best sounding valve.

Agree.
On this moment definitely i thick only - output power 0.1-1 watts, and impendance 32-42 Ohm.
Other parameters - too width range of conditions.
Just best sound.

1626
Kenzie - ampsandsound

Thanks!
Great!
I don`t hear earlier about 1626 and VT-137.

 

[piano3]

The datasheets say 4.5 watts at 4% THD for a SE PX4- a bit better than 2A3. The Soviet 4P1L is very popular on this forum and there are a number of lengthy threads you can check.

 

[kodabmx]

I use 6N6P in my OTL HP amp...

 

[DocOct]

Thanks!
Great!
I don`t hear earlier about 1626 and VT-137.

Another good tube in that amp is the 12B4 tube using an adapter. It will yield a bit more power and is more open sounding. They glow nicer too!!

 

[piano3]

I used a 6n6p in a headphone amp too-but with an OPT.

 

[Kashtan]

The datasheets say 4.5 watts at 4% THD for a SE PX4- a bit better than 2A3. The Soviet 4P1L is very popular on this forum and there are a number of lengthy threads you can check.

PX4 first generation take much small power - 1 watt.
PX4 audio valve, power triode technical data
They sound too very better then next generations with much higher power.

 

[piano3]

I see; these must be very expensive though?

 

[kodabmx]

I used a 6n6p in a headphone amp too-but with an OPT.

I use this circuit The output is push pull though.

 

[Lingwendil]

How about trode connected 4P1L? Can do a single per side or parallel them as needed. Triode connected 6P15P will also come very close.

Hard to beat a triode connected 6V6 too.

Or, if you don't have to be SE, a nice little 6SN7 push-pull?

 

[Kashtan]

I see; these must be very expensive though?

Sure, overprice - much higher them $1000 usd a pair.
I don`t very long finding.

 

[piano3]

Very nice Koda, but will it really drive 32 Ohm 'phones?

 

[kodabmx]

Actually, yes it will. It can swing 40mA into the load which is only 50mW into 32R though. Still, 50mW is plenty for sensitive cans. My main set is actually 470R though so it'll push 750mW into them!

 

[Wavebourn]

Try 6P15P in triode mode. You will be surprised. Less problematic filament and bias than with 4P1L.

 

[nigelwright7557]

I use the EL84 in push pull for low power amplification.

 

[multi]

What is the max voltage triode connected 6P15P?.

 

[kodabmx]

Not sure what the max is, but I'm running a set at 260V or so and they're fine. Screen connected to plate through 220R.

 

[piano3]

I have some datasheets for the -ER suffix type which states 330 V for both anode and screen.

Also, 65 mA cathode current max, which is useful since most of the other datasheets just give a pulse current max. Maybe needs a bit of derating since the -ER has a slightly (800 mA) more powerful heater.