Difference between one or two tubes in Amps

Off-Topic
1

Hello,

I have a hybrid amplifier here for testing.
It is only equipped with one tube from JJ Electronic (Ecc88).

The performance data is quite acceptable and it drives the planar headphones quite well, especially the DC Aeon R/T.

However, there are two things that bother me about the amplifier.
When I plug the R/T into the Little Dot 1+, there is a tonal musical way of listening to music that relaxes me and is fun to listen to.
And a great resolution that goes deep.

When I plug the R/T into the amp I’m testing, I notice that the sound is kind of good and kind of not.
The bass is extremely dominant and the mids are a little more distant than usual, as are the highs.
So it feels like I’m standing 5 metres away from the stage.

The next point is when I plug the Emu Purpleheart headphones into the Little Dot, similar to the R/T described above.
Nice and smooth, musically rich and full of sound.

Then when I plug them into the amp I’m testing, it starts to sound mainly muddy, less musical, even more distant from the stage than with the R/T.
And now I was wondering what the reason could be?
The tubes themselves with the difference between one or two tubes.
The tube family itself? With the difference between Ecc88 and Ef92.
Or simply the amplifier construction or tuning?

At the moment I feel more like putting the amp I’m testing back in its box and returning it.
However, I am still looking for an explanation.
Also because the JJ tube is actually not bad and is built into well-known amplifiers.

1 Like
2

tubes, by default, add distortion. depending the tube, depends on to what effect.

i would say its amp design, and not 1 vs 2 tubes.

2 Likes
3

Okay, I almost suspected that a little bit.
If I use the Vali 2 as a reminder, the Vali was indeed better, but it had little effect on the tube.
This one reacts relatively well to the tube change, but it still inhibits something.

It seems to me as if it has a jam :sweat_smile:.
It probably can’t be due to the burn-in phase, can it?
The part was built in a relatively minimalist way, so a short burn-in phase of 20-30 hours should probably be enough, except for the tube, which is a bit worn.

1 Like
4

@joshua_g what are the primary reasons for the use of multiple tubes? I know it can often be left and right channel targeted…but what else?

1 Like
5

More power. Each additional tube adds more power. Both for pre-amp tubes and power tubes.

2 tubes vs 1 should add more tubyness in the pre-amp section for instance as it adds a little more distortion

Edit: there’s more, but I’m at work. Go into more detail later. That’s a very general discription

1 Like
6

So in the two years that I’ve been experimenting with tube amps after only having the Vali for a short time and also now with the test unit that only has one tube.
I have come to the conclusion that more than one tube on a hybrid amplifier or tube amplifier makes more sense than one.
Especially after having heard an Otl, this becomes very clear.
When I heard the Little Dot 1+ for the first time it was exactly that oh wow, if it had any more bite it would be perfect.

2 Likes