Mixing makes of 6DJ8 tubes in preamp, and how to ascertain best position.

[LL21]

Spriritofmusic,

I suggest you tell Brent what sound qualities you are looking for the component to produce more of or less of...tell him what the existing stock tubes are...and ask him what he thinks about NOS options. He often DOES recommend different tube brands based on what you are looking for in sound terms.

 

[bonzo75]

Spriritofmusic,

I suggest you tell Brent what sound qualities you are looking for the component to produce more of or less of...tell him what the existing stock tubes are...and ask him what he thinks about NOS options. He often DOES recommend different tube brands based on what you are looking for in sound terms.

Lol you should warn Brent otherwise the discussion will go on forever

 

[Zero000]

Brent goes to great lengths discussing the sonic attributes of various tubes. Trouble is I found reality and Brent's descriptions to be two different things in practice.

Hardly surprising I guess. We're just as bad on the Lampi threads trying to discuss what we hear with various different valves.

I have spent quite long while over the years reading his website. I like it. True valve nut job, so respect is due

 

[Zero000]

BTW Marc if your think your valves are noisy try a projector LOL.

 

[spiritofmusic]

Spriritofmusic,

I suggest you tell Brent what sound qualities you are looking for the component to produce more of or less of...tell him what the existing stock tubes are...and ask him what he thinks about NOS options. He often DOES recommend different tube brands based on what you are looking for in sound terms.

Oh Lloyd...I'd quite like the tubes to make me more attractive to women, bring me riches and great health.
Short of THOSE...I'm already getting a lot of positives, especially in areas of sweetness, silkiness, saturated tonal color.
Critically, the vast majority of tube hash is gone leaving much more natural detail resolution.

No, my dilemma is that I wasn't expecting Brent to recommend a mix of brands.

The good news is I've already hit a sweet spot and if Lowrider's advice is correct, I just need to compare

Mullard-Mazda-Mazda-Mullard, versus
Mazda-Mullard-Mullard-Mazda, and see if I hit upon the best sound.

 

[spiritofmusic]

Lol you should warn Brent otherwise the discussion will go on forever

Maybe...however it seems Brent likes to talk more than me.

 

[Lowrider75]

Lowrider,
Left to right, 12 34
With 6s19p-v tubes at extreme right and extreme left
So, you would suggest one type at 1 & 4, the other type at 2 & 3?

I saw a pic of your preamp. The small signal tube layout is 12 Left, 34 Right. Not 1234.
So, left side is left channel with a gain tube and a driver. Right side is Rt channel gain and driver.
There is no way to tell which is gain and which is driver. I suggest use the Mullard on inside tubes. Those will be a match for left and right. Then you can swap 1 and 2, and 3 and 4 to see which sounds best. Always keep the tubes matching for left and right channels.

 

[Zero000]

Maybe...however it seems Brent likes to talk more than me.

He couldn't be trying to sell you something could he?

 

[spiritofmusic]

He couldn't be trying to sell you something could he?

Well, I need some 6N1P-EV and 6S19P-V tubes, but he couldn't help.

 

[spiritofmusic]

I saw a pic of your preamp. The small signal tube layout is 12 Left, 34 Right. Not 1234.
So, left side is left channel with a gain tube and a driver. Right side is Rt channel gain and driver.
There is no way to tell which is gain and which is driver. I suggest use the Mullard on inside tubes. Those will be a match for left and right. Then you can swap 1 and 2, and 3 and 4 to see which sounds best. Always keep the tubes matching for left and right channels.

Lowrider, so start
LEFT: Mazda-Mullard Mullard-Mazda :RIGHT
then try
LEFT: Mullard-Mazda Mazda-Mullard :RIGHT

and then decide?
PS Lowrider, I salute your forensic skills, the photos online of Nat gear number the fingers on my hands, to find a pic of Utopia chassis revealed is impressive.
Thanx for your invaluable feedback.

 

[Lowrider75]

Lowrider, so start
LEFT: Mazda-Mullard Mullard-Mazda :RIGHT
then try
LEFT: Mullard-Mazda Mazda-Mullard :RIGHT

and then decide?
PS Lowrider, I salute your forensic skills, the photos online of Nat gear number the fingers on my hands, to find a pic of Utopia chassis revealed is impressive.
Thanx for your invaluable feedback.

Let's slow down and make sure I'm looking at the right preamp.
It says Nat Utopia, middle of page there's a two chassis preamp.

Dropbox

www.dropbox.com

4 6DJ8
2 6s19p-v

 

[Lowrider75]

The 6s19p-v are in the middle in this Nat.

 

[spiritofmusic]

I can't access that link, but yes, Nat Utopia.
Tube layout is as you describe.

 

[Lowrider75]

Lowrider, so start
LEFT: Mazda-Mullard Mullard-Mazda :RIGHT
then try
LEFT: Mullard-Mazda Mazda-Mullard :RIGHT

and then decide?
PS Lowrider, I salute your forensic skills, the photos online of Nat gear number the fingers on my hands, to find a pic of Utopia chassis revealed is impressive.
Thanx for your invaluable feedback.

Without instructions from the designer, that's worth a try. FYI,
the Mullard has a warm sound with not much high-end extension. The Mazda will be more transparent with airy highs.

Change them one at a time until the music sounds more focused.

 

[spiritofmusic]

So, just these two permutations?

 

[bazelio]

That Mullard isn't typical overly warm Mullard fare in the applications I've used it. It doesn't have the snap and dynamism of the Mazda, but it has more body, isn't syrupy, and detail is reasonably good. This is why I suggested the combo to Marc. All that said, tubes don't have a sound. It's always the entire circuit that creates the sound. Marc just needs to try some combinations and see what he hears. At this point, it's been (over)analyzed to death while still being complete shots in the dark (e.g. the assumption the inside-outside is mirrored left to right). Note to self to avoid NAT given the apparent total absence of comms.

 

[Lowrider75]

So, just these two permutations?

That Mullard isn't typical overly warm Mullard fare in the applications I've used it. It doesn't have the snap and dynamism of the Mazda, but it has more body, isn't syrupy, and detail is reasonably good. This is why I suggested the combo to Marc. All that said, tubes don't have a sound. It's always the entire circuit that creates the sound. Marc just needs to try some combinations and see what he hears. At this point, it's been (over)analyzed to death while still being complete shots in the dark (e.g. the assumption the inside-outside is mirrored left to right). Note to self to avoid NAT given the apparent total absence of comms.

What type of Mullard is it?
Longplate square getter, Longplate O-getter,
Shortplate?

 

[spiritofmusic]

Brian, proof is always in the pudding.
Tbh, I'm gonna just stick to these two combinations, and see what transpires.

Re not going Nat...well, I can't deny comms are poor w them. What I also can't deny is how good the sound is.

Good news is that my teething issues are behind me, and SQ is massively enhanced. I've now ordered some '80s NOS gold pin Voskhod Rockets 6N1P for my SE2SE monos, and if I can drag tube bias voltage info out of Nat, I'm seriously considering the Mayer Elrog 211 tubes.

 

[spiritofmusic]

What type of Mullard is it?
Longplate square getter, Longplate O-getter,
Shortplate?

Lowrider, sorry I can't help there, I only buy the things.

 

[tima]

Tim, there's my issue. Nat Audio are in Belgrade, almost never answer emails, noone speaks fluent English.

Tbh, I'm not sure what I should be asking...the stock tubes are all one brand. The last thing I was expecting Brent to recommend was two brands of 6DJ8 tubes. Hence my quandary.

Hmmm ... too bad about the manufacturer.

Did BJ say why he recommended two different brands of 6DJ8 when stock is all the same? That's kinda strange. Mullards and Mazda - that's something you'd do when you only have two of each left. Using one to compensate or counter balance for the other.

Four NOS '70's Amperex 6922 Orange Globes would have done the trick for not much dinero.

But, sounds like you're settled with what you have. Have fun rolling.