Dear all,
I'm trying to differentiate between 6N6P and 6N6P-I. What I've read so far here, the "I" versions have higher cathode dissipation - is it true ? I mean wherever I look for 6N6P datasheet, I can find it, but no datasheet for 6N6P-I.
The circuit I want to build is this one here, a pretty simple, forgiving one and I'm not sure if my NOS 6N6P-I tubes would just fit into that 1:1 (instead of originally planned 6N6P without the "I").
Schematics - that black circuit diagram
I'm trying to differentiate between 6N6P and 6N6P-I. What I've read so far here, the "I" versions have higher cathode dissipation - is it true ? I mean wherever I look for 6N6P datasheet, I can find it, but no datasheet for 6N6P-I.
The circuit I want to build is this one here, a pretty simple, forgiving one and I'm not sure if my NOS 6N6P-I tubes would just fit into that 1:1 (instead of originally planned 6N6P without the "I").
Schematics - that black circuit diagram
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The version -I, is the same anti vibration/pulse valve, at the sound level it is less than 6N6P, smaller bulb with less capacity to dissipate heat, a little more power, somewhat less quality in audio than 6N6P but it may sound good better than chinesse , equal pins, directly interchangeable without need of no change in the circuit Possibly the tolerance between triodes is greater. 500h life.
I have compared the sound in the BIJOU Head-Amp
I have compared the sound in the BIJOU Head-Amp
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I assume you have read this entire thread, which, I thought, provides the answer to your question; post #3 summarizes it very well. So, I’m not sure why you are asking, are you looking for something specific?
Post #24 provides a link to tube data which includes the 6N6P-I. I believe the “I” version is a 6N6P that is tested and qualified for specific characteristics that suited Impulse duties, and it may have a cathode coating enhanced for higher emission. In this duty it is rated for 500 hours. Since it is not qualified for audio use it may (or may not) have off specs parameters if used as “regular” 6N6P. I have not studied the performance curves of the two versions of 6N6P, but there seems to be differences. Check it out.
Since you have the I-versions, I don’t think you will hurt the amplifier by trying them carefully, listen and measure for excessive current.
Fernan: Suffix I is for Impulse, K is for vibration, per post #14. Interesting to know you have used and compared both versions. Did you check and compare the plate currents?
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YES, I would instead go with them quietly, carefully in V cathode heaters, I think 120V for -I
Hello Francois!
I did not know -K, if I read something about shock vibration the use of -I and not the normal one.
I did not take measurements, I took the same for granted,
(or differences such as others for example -EB and not -EB)
I noticed more heat, but no more power in the ears,
I thought it was because of the larger large plates, tucked into the smaller bulb.
The SRPP circuit can make a lot of difference in driving even with 6N6P.
(I had no more interest in them, having good 6N6P in stock)
Best Regards
Fernan
Interesting! Do the 6N6P-I have larger plates than the “regular” one. I have not seen a 6N6P-I, but assumed both versions would look exactly the same. No? I thought only the cathode was modified or greater pulse current.
Only photos can be published through URL :?
My assessment was incorrect, the plates are the same size, the bulb is a little smaller in -I,
(re- don't pay attention having good 6N6P either)
Well, this is one of the main drawbacks of this forum: no persistence. Everything can only be linked pointing to an outside site and if these fail or get suspended, the golden info is lost - which is exactly the case in post #2's links.
(Same with images).
Object not found!
The requested URL was not found on this server. If you entered the URL manually please check your spelling and try again.
If you think this is a server error, please contact the webmaster.
Error 404
www.mif.pg.gda.pl
Thu Apr 16 11:43:03 2020
Apache/2.2.12 (Linux/SUSE)
Meanwhile I found a photo on the internet from a bunch of 6N6P-I tubes & an original old Russian datasheet paper of them, I managed to figure out the differences between the two. (And I also found a direct comparison PDF about them but this needed a little bit more time, digging long on the net).
My questions are answered now, thank you
Would you be kind enough
to share this information with those of us that tried to help you?My impression from a couple of years ago (I ditched the I-version at once after comparing):
The 6N6P is a formidable tube for audio. Warm, lush and a pleasure to listen to.
The I-version has a glassy sound signature, which marks specially the upper middle and treble to sound slightly agressive.
In my ears a pain to listen to.
First impessions don´t last very long, and then you wish yourself back to the non-I-version.
The only manufacturer I know who has the I´s in high regards is B.A.T., and I really don´t understand why.
Just my 5 cents
The 6N6P is a formidable tube for audio. Warm, lush and a pleasure to listen to.
The I-version has a glassy sound signature, which marks specially the upper middle and treble to sound slightly agressive.
In my ears a pain to listen to.
First impessions don´t last very long, and then you wish yourself back to the non-I-version.
The only manufacturer I know who has the I´s in high regards is B.A.T., and I really don´t understand why.
Just my 5 cents
Would you be kind enough
I thought you already have the info. How can I upload PDF ? I'm trying to figure out something here..
Just for you..
Thanks much! I got it. Good luck.
My impression from a couple of years ago (I ditched the I-version at once after comparing):
The 6N6P is a formidable tube for audio. Warm, lush and a pleasure to listen to.
The I-version has a glassy sound signature, which marks specially the upper middle and treble to sound slightly agressive.
In my ears a pain to listen to.
First impessions don´t last very long, and then you wish yourself back to the non-I-version.
The only manufacturer I know who has the I´s in high regards is B.A.T., and I really don´t understand why.
Just my 5 cents
Thanks for the feedback.
As a nice gift from the seller I got 2 6N6P-s also in the box (the non-I versions). And I also have 2x JJ ECC99 so I think I'll just listen to all and then we'll see which of these suit my subjective listening the best.
Per the linked datasheet, the -I and the non -I versions of the tube are identical with only the heater beeing different. Heating power is increased by one Watt (.75A vs .9A heating current, 4.72 W vs 5.67 W). This will run the cathode much hotter and allow higher cathode pulse currents - and will reduce lifetime as a consequence. The -I version seems to be developed for missile applications as there are additional specs available for vibrations and accelerations even with specified vibration frequency ranges.Just for you..
Would be interesting to compare both tubes with the I version having a reduced heater voltage to run both with the 4.7 W nominal heater power of the 'normal' 6N6P. Maybe sonics get more similar then.