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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 377

post #5641 of 7334
Quote:
Originally Posted by gibosi View Post
 

... maintaining the correct internal left and right orientation ...

 

The tube doesn't really care which triode system you use for left contra right channel.

post #5642 of 7334
Quote:
Originally Posted by Oskari View Post
 

The tube doesn't really care which triode system you use for left contra right channel.

 

As I don't have power tubes in my hybrid, I always try to err on the side of caution when giving my 2 cents. But now that you mention it, it is obvious: The tube doesn't care. lol :)

post #5643 of 7334
Quote:
Originally Posted by Oskari View Post
 

 

The tube doesn't really care which triode system you use for left contra right channel.

 

Thanks Oskari (and gibosi) for stating what I should have known for sure...ah well, can't ever be too careful when making adapters!...

 

Cheers.


Edited by hypnos1 - 3/28/14 at 9:28am
post #5644 of 7334

They sourced years ago for their transceivers. I doubt they ever manufactured their own.

post #5645 of 7334

I should have my c3g tubes and adapters potentially tomorrow, Monday at the latest based on tracking! :atsmile:

post #5646 of 7334

ECC40

 

I wonder... Am I the only one rolling these tubes?

 

Anyway, I now have about 15 of these in my possession and thought I might share some of my observations.

 

In the late 1940's and into the 1950's, these were manufactured in at least 5 Philips factories: 

 

Eindhoven, Holland (factory symbols: "4", "5" and "H". The "H" appears to be a miss-shaped 4, as they look and sound the same to me.)

 

Sittard, Holland (factory symbol "+")

 

Chartres, France (factory symbol "±", that is a "+" on top of a "-")

 

Suresnes, France (factory symbol "F")

 

Hamburg, Germany (factory symbol "D")

 

And in addition to Philips, Tungsram also made this tube. However, I have yet to spend any quality time with mine.

 

By the late 1960's it appears that most of Philips' ECC40 production seems to have been located in Chartres, as the vast majority of the tubes I see from that time were manufactured there. And into the 1970's, some tubes were also manufactured at Suresnes and the Ediswan factory in Britain, according to one vendor, but I do not have any of these, so I am not sure.

 

Generally, I like the Chartres-made tubes the least. I find the highs to be a bit over the top. The Hamburg-made tubes have the airy highs and dryish mids typical of German-made tubes, and although, this is not my favorite sound signature, still, it is quite nice. And the Holland-made tubes seem to do everything quite right (to my ears).

 

Last night I spent several hours with a Suresnes-made tube and was surprised to discover that I really liked it. Interestingly, the Suresnes-made tubes look rather different than the tubes from all the other Philips factories. The bottle is shorter, the plates are somewhat different, and the metal work above the top mica and below the bottom mica is also different.

 

1952 Suresnes production compared to 1955 Eindhoven

 

 

 

And the ECC40 metal-base variants also look different.

 

Early 1950's Suresnes production compared to 1951 Hamburg

 

 

I hope others will try these tubes and let us know what they think. To begin, I can easily recommend the Suresnes, Hamburg and the various Holland tubes. :)


Edited by gibosi - 3/28/14 at 1:48pm
post #5647 of 7334
Quote:
Originally Posted by mab1376 View Post
 

I should have my c3g tubes and adapters potentially tomorrow, Monday at the latest based on tracking! :atsmile:

 

Hey mab, I don't know who's more like the proverbial "cat on a hot tin roof" - you or me!! Can't wait!!...

 

As for me, my Sylvania 6SN7GT-VT231s are waiting in my local post office, so tomorrow we could both be having an interesting time :C3GS vs ???..., and Psvane CV181-T MKII v Sylvania. The suspense is just TOO much...this rolling game sure does get the juices flowing (not to mention nervous exhaustion!!).

 

GOOD LUCK!


Edited by hypnos1 - 3/28/14 at 1:54pm
post #5648 of 7334

I just noticed the voltage reading on my multi meter that the length of the wires are affecting the voltage reading at 12'' = 6.35V and at 20" = 5.98V.

Does it mean if i connect my adapter wires closer to the PCB would have a little bit better sound maybe.

post #5649 of 7334

Or the shorter the signal path the better?

post #5650 of 7334
Quote:
Originally Posted by i luvmusic 2 View Post
 

I just noticed the voltage reading on my multi meter that the length of the wires are affecting the voltage reading at 12'' = 6.35V and at 20" = 5.98V.

Does it mean if i connect my adapter wires closer to the PCB would have a little bit better sound maybe.

 

Again, I am certainly not an expert, but it is hard for me to believe that 8 inches of wire causes that large of a voltage drop. I have to believe that something else is causing this. But there are others here who know much more than I.... :)

post #5651 of 7334

I find that different tubes give different voltage readings at the tube pins. When I change a tube I adjust the pot to read the correct voltage at the tube. The LED readout or multimeter reading is usually a bit higher measured at the voltage regulator. As an example, the 6P6N-IR as a driver needs 6.3V, but the voltage regulator value has to be 6.45V to achieve this at the breadboard socket in my case.

 

Regarding wires I am skeptical. IMHO a foot or two should not make a difference. Me thinks some fancy interconnects work as tone controls....Of course, then you have silver.....


Edited by mordy - 3/28/14 at 3:20pm
post #5652 of 7334

I tried again measuring using even longer wires and again it dropped even lower.Same here G i'm not an expert but  this suggest to me that the shorter the signal path the better maybe no effect on sound quality.You mentioned about 6N6 as a driver tube i would like to try these if you or anybody can post the pin connections since Mordy(sorry Mordy) is having fun with his new driver tubes while i'm bored waiting for my parts from Chinada.Thanks!

post #5653 of 7334
Quote:
Originally Posted by i luvmusic 2 View Post
 

I tried again measuring using even longer wires and again it dropped even lower.Same here G i'm not an expert but  this suggest to me that the shorter the signal path the better maybe no effect on sound quality.You mentioned about 6N6 as a driver tube i would like to try these if you or anybody can post the pin connections since Mordy(sorry Mordy) is having fun with his new driver tubes while i'm bored waiting for my parts from Chinada.Thanks!

 

6H30-type tubes have the same pin-out as a 6DJ8.

post #5654 of 7334
Quote:
Originally Posted by gibosi View Post
 

 

6H30-type tubes have the same pin-out as a 6DJ8.

So i can connect pin 4 and 5 to  - and + from external PS and pin 9 no connection?Thanks!


Edited by i luvmusic 2 - 3/28/14 at 4:05pm
post #5655 of 7334

Sorry to say that i will be busy listening to 6n6 driver tube Holy schiit it works no hum dead silent...

 

 

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