About 6n1 tubes.

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cafyon

About 6n1 tubes.
« on: 18 May 2011, 03:43 pm »
Hello,

I have a HCT HMS-100 hybrid amp (OEM of Fatman iTube or Dared MP-5) with Chinese 6n1 tubes as input. It's time to replace these 6n1 tubes. When I search for them on the net, I come across three tubes:

- 6n1j (or 6n1 j-grade, it's said)
- 6n1p (or 6n1p-ev)
- 6h1n (I have no idea about this one. It's said it is the Russian equivalent  :dunno:)

Although HMS-100's manual comments under the exact title as follows...
The Use Vacuum Tube: 6N1 (ECC85) x2
...as far as I know there are NO direct, 1-to-1 western replacements for 6n1 tube.
BTW, Fatman iTube's manual, also, suggests the same.

I want to ask, what do "j" or "p" (or 6h1n itself) stand for in those 6n1 tubes' designations?
Are they direct, 1-to-1 replacements for 6n1 tubes in my HCT amp?
A different route which I won't be fond of: Shall I look for ECC or 12xxx tubes?

BTW, I noticed that the input tubes on Dared MP-5 are 12AX7. But I have no idea whether MP-5's and HMS-100's circuits are equivalent or not!

:wave:

JakeJ

Re: About 6n1 tubes.
« Reply #1 on: 18 May 2011, 08:24 pm »
Welcome to AudioCircle, cafyon!

Sorry I can't answer your question, all I found was this: http://frank.pocnet.net/sheets/095/6/6N1.pdf and I don't read chinese.  The 6N1P has very similar electrical ratings but they aren't an exact match so it will depend on whether the mfr will recommend it or not.

Not much help, I know, but maybe someone else can chime in.

skriefal

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Re: About 6n1 tubes.
« Reply #2 on: 19 May 2011, 12:45 am »
- 6n1p (or 6n1p-ev)
- 6h1n (I have no idea about this one. It's said it is the Russian equivalent  :dunno:)

There is no "6H1N".  Those are actually 6N1P tubes.  The Cyrillic characters do look like an "H" and an "N"... but they actually translate to an "N" and a "P".  So "6H1N" and "6N1P" should be considered to be two ways of referring to the same tube... with one (the former) being incorrect but nonetheless relatively common.

6N1P-EV is just a 6N1P that has been tested and rated for more heavy-duty use.

Nels Ferre

Re: About 6n1 tubes.
« Reply #3 on: 19 May 2011, 12:47 am »
6N1P circuits can usually take a 6922 or 7308. Do not try a 6H30- they draw more current.

JerryM

Re: About 6n1 tubes.
« Reply #4 on: 19 May 2011, 01:07 am »
There is no "6H1N".  Those are actually 6N1P tubes.  The Cyrillic characters do look like an "H" and an "N"... but they actually translate to an "N" and a "P".  So "6H1N" and "6N1P" should be considered to be two ways of referring to the same tube... with one (the former) being incorrect but nonetheless relatively common.

6N1P-EV is just a 6N1P that has been tested and rated for more heavy-duty use.

skriefal is right. A 6N1P is frequently branded as 6Н1П . As the final symbol is not a common keyboard character, we get 6N1.

The 6N1P is very close to the 6DJ8, but demands much more heater current.

Have fun,

Jerry

Steve

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Re: About 6n1 tubes.
« Reply #5 on: 19 May 2011, 01:26 am »
skriefal is right. A 6N1P is frequently branded as 6Н1П . As the final symbol is not a common keyboard character, we get 6N1.

The 6N1P is very close to the 6DJ8, but demands much more heater current.

Have fun,

Jerry

Actually there are some major differences, although some use them interchangeably. Whether the conditions are optimal depend upon the particular design used.

1) As mentioned above filament current is more, so make sure the filament supply/regulator will work.

2) The plate voltage rating is much higher with the 6n1p than 6dj8. The plate voltage used in a particular 6n1p design/circuit may be too high for the 6dj8, unless the plate current is at or below a certain value, typically 6.0 ma or .006 amps.

3) The transconductance is some 4 times greater with the 6dj8 than 6n1p. The plate resistance of the 6n1p is some 4 times that of a 6dj8. Miller capacitance is also 20% or so greater. This needs to be taken into account as the frequency response could be much worse for a given design.

Cheers.

 

JoshK

Re: About 6n1 tubes.
« Reply #6 on: 19 May 2011, 01:48 am »
As I see it the 6N1P isn't really a 6DJ8/6922 so much as its own tube that is somewhat similar in gain.  Its a betweener, somewhere between a 2C51 and a 6922.  Supposedly sounds great in the right circuit though. 

JoshK

Re: About 6n1 tubes.
« Reply #7 on: 19 May 2011, 01:49 am »
The russian 6N23P is the equivalent of the 6DJ8.

richidoo

Re: About 6n1 tubes.
« Reply #8 on: 19 May 2011, 04:38 am »
I had a preamp that used 6N1P. The manufacturer said no other tube would work. So I compared the stock tube to 15yo Svetlanas and to vintage military 6N1P from the 60s. They all sucked. The manufacturer changed the design soon after to use more common tubes. Those were the only 6N1Ps that I was aware of at the time, but maybe the Chinese Shuguang 6N1 tube is better. I love their 12au7 as used in EE products. Certainly the fatman was voiced using the Shuguang tube rather than a russian. I'd stick with it. Grab an extra so you won't miss any tunes it one fails. ;)

JoshK

Re: About 6n1 tubes.
« Reply #9 on: 19 May 2011, 04:54 am »
I don't mean to be combatitive, but the 12au7 is one of the highest distortion tubes in extant (and not just pleasing low order, but substantial high order distortion as well), at least amongst those used in audio, while the 6N1P is quite linear (low distortion).   All the reports I've read about the Chinese 6N1Ps haven't been kind in terms of reliability while the soviet era 6N1P-ev's are suppose to be bullet proof.  Go figure.

richidoo

Re: About 6n1 tubes.
« Reply #10 on: 19 May 2011, 05:07 am »
Yeah, you have to figure the circuit in any comparison of tubes. I searched for 12au7 tubes for a long time and didn't like the warm vintage sound, nor teles or cleartop RCAs. The EE tubes were excellent in the EE minimax. Since all 6N1Ps sounded awful maybe the circuit had more to do with it than the tubes. I've read some great things about 6n6p, but i don't know if it is related to 6n1P

mark funk

Re: About 6n1 tubes.
« Reply #11 on: 19 May 2011, 10:08 am »
If you are looking for some 6N1Ps made in the CCCP (Russina) in 1977 I have some for sale!
PM me if you want some.


                                                                                    :smoke:

JakeJ

Re: About 6n1 tubes.
« Reply #12 on: 19 May 2011, 03:39 pm »
Thanks, Guys!

I knew there would be some answers out there.  I had read the arguments that the 6N1P was/was not a direct sub for the 6922.  But in learning about tubes I came to realize that a direct substitute must have all the electrical parameters matched or it's not really a direct sub.  Some circuits will handle tubes that are slightly different but that is just the nature of electronics, they can be forgiving to some degree.

So it would seem you need to find the exact tube to replace yours and your choices are somewhat limited.  Maybe with some research you will find a particular batch or run of these tubes is better than the rest and can buy some of those.  And I'll second richidoo's recommendation of buying some extras if you can afford it.

JoshK

Re: About 6n1 tubes.
« Reply #13 on: 19 May 2011, 04:32 pm »
I've read some great things about 6n6p, but i don't know if it is related to 6n1P
the 6n6p has more in common with the 5687 and 6n30p (often written 6h30pi) but again not quite the same. 

tomsum20

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Re: About 6n1 tubes.
« Reply #14 on: 19 May 2011, 05:08 pm »
The HCT/Fatman small amps use ECC85 (AKA 6AQ8) in place of the 6N1s. They are readily available and cheap. I have a couple of these little amps.

Tom

2wo

Re: About 6n1 tubes.
« Reply #15 on: 31 May 2011, 04:39 am »
I have a pair of "gold Lion" labeled 6DJ8, that i have had for 20 years or so. I just got a DAC kit with a 6N1. The 6N1 has a very distinctive internal structure and it is identical to the Gold Lion down to the smallest detail...John