In search for very quiet tubes one might have to select JJ E88CC , i.e. either
scan them yourself or find a vendor willing to select quiet ones.
I was just wondering whether the JJ E88CC had improved recently, not so much where to buy them.
A few years ago, I was on a quest to find the lowest noise current production tubes, and the JJ E88CC was one of the tubes I measured. I've re-posted the data below, showing noise histograms for both the JJ 5751 and the JJ E88CC. The E88CC samples were highly variable, and even the best E88CC were no better than the 5751. The E88CC (and 6DJ8) have the reputation of being low noise, probably because there used to be good NOS ones. But among tubes I've tried, it just isn't the case. If low noise is the goal, there is no reason to prefer them over the JJ 5751 or JJ ECC83.
But if they've improved, I might measure them again. I measure JJ 5751 frequently, and they've stayed about the same (which is good).
Scott
A few years ago, I was on a quest to find the lowest noise current production tubes, and the JJ E88CC was one of the tubes I measured. I've re-posted the data below, showing noise histograms for both the JJ 5751 and the JJ E88CC. The E88CC samples were highly variable, and even the best E88CC were no better than the 5751. The E88CC (and 6DJ8) have the reputation of being low noise, probably because there used to be good NOS ones. But among tubes I've tried, it just isn't the case. If low noise is the goal, there is no reason to prefer them over the JJ 5751 or JJ ECC83.
But if they've improved, I might measure them again. I measure JJ 5751 frequently, and they've stayed about the same (which is good).
Scott
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It has been said before:
Most vendors who sell JJ tubes do not do Extensive testing.
And how many of them have sold all their old stock?
Eurotubes does Extensive re-testing.
The owner and his son have been to the JJ factory in Slovakia may times.
They work together. Eurotubes is a major customer of JJ.
The factory is constantly improving their manufacturing equipment and processes.
Better tubes, more repeatable, etc.
By the way, a lot of the JJ tubes use spiral wound filaments.
I first discovered this when I purchased an ECC82, probably over 10 or 15 years ago.
One of the early companies that produced the 12AU7 equivalent specified spiral wound filaments.
How many of you knew that?
How long ago, and where did you get your JJ tubes?
Just sayin'
Most vendors who sell JJ tubes do not do Extensive testing.
And how many of them have sold all their old stock?
Eurotubes does Extensive re-testing.
The owner and his son have been to the JJ factory in Slovakia may times.
They work together. Eurotubes is a major customer of JJ.
The factory is constantly improving their manufacturing equipment and processes.
Better tubes, more repeatable, etc.
By the way, a lot of the JJ tubes use spiral wound filaments.
I first discovered this when I purchased an ECC82, probably over 10 or 15 years ago.
One of the early companies that produced the 12AU7 equivalent specified spiral wound filaments.
How many of you knew that?
How long ago, and where did you get your JJ tubes?
Just sayin'
Last edited:
I updated our list of tube noise measurements to include more data. We had the opportunity to measure a collection of 24 NOS 6DJ8 types (6922, E88CC, E188CC) that had been previously selected for low noise. These premium tubes included Telefunken, Philips, Siemens, Amperex, and Valvo tubes from the 1960s and early 1970s. A tube enthusiast and collector spent much time and money assembling this collection, which is definitely not representative of typical NOS 6DJ8 tubes now available. They had an average input-referred noise of 0.61 µV rms, with a ±0.21 µV rms sample standard deviation. There were 9 tube sections which measured < 0.5 µV rms.
The 6DJ8 has a reputation for low noise, and this collection of tubes shows why. Current-production 6DJ8 types we’ve tested haven't been as good. The attached figure shows a noise histogram for these 24 NOS tubes, with a few very noisy sections omitted, since they would lie off the right of the graph. There are also some photographs of this collection under test.
Cheers,
Scott
The 6DJ8 has a reputation for low noise, and this collection of tubes shows why. Current-production 6DJ8 types we’ve tested haven't been as good. The attached figure shows a noise histogram for these 24 NOS tubes, with a few very noisy sections omitted, since they would lie off the right of the graph. There are also some photographs of this collection under test.
Cheers,
Scott
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