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Ducatista47
11-05-2006, 11:35 AM
This goes out to any interested EL84 users. I have a single ended EL84 amp, a Grommes PHI-26. I have done some tube rolling and have finally found a real winner.

At the suggestion of the designer, I tried the Soviet era 6P14P-EV. That is 6n14n-EB, more or less, in cyrillic. I obtained examples from Europe at: http://www.audiotriodes.com/

EL84M tubes and new Electro-Harmonix stock are in no way the equivalent of these NOS 6P14P-EV units, despite E-H (New Sensor, actually) now using the old Reflektor factory in Saratov where these were manufactured.

Noise is low to the point of extinction. In my amp's triode mode, the improvement over EH or JJ's was not subtle. Night and day. Tone is in a whole different class and power, mysteriously, is up at least 6dB, maybe much more. The tubes will make the trip over just fine, as the specs for mechanical toughness are off the scale. These were designed for military field use, after all.

The only strange thing about them is warmup. Even a lengthly warmup does not prevent the volume level from starting off very low and building up to normal after one song or so. At least on my amp. So wait for it. Playing music seems to do the trick. Again, no explaination.

There are plenty of Russian sites that have this tube, but I don't trust them personally. I can vouch for Audiotriodes, and their shipping was dirt cheap. The prices are in Euros, just use a converter to figure it out if you are not located in Europe.

The bad news is that guitar amps are burning up NOS tubes at a furious rate, and the new stock plant is having "Russian" troubles. http://www.6moons.com/industryfeatures/newsensor/newsensor.html

Clark in Peoria

scott fitlin
11-05-2006, 11:56 AM
I agree with you about NOS tubes. I have a piece that uses a 12AX7A, it comes with either a Ruby or Sovtek, they were OK, then I got some NOS Amperex 12AX7A,s from the `60,s. WOW, what a difference, not subtle either. Everything just sounds sooo right, so acoustic, so natural, easy on the ears, yet really dynamic and crystal clear beyond anything i have ever experienced.

So, because I am aware of the fact that NOS tube supplies are being depleted quickly, and once gone, thats it, they are gone, I ordered enough of a supply to last me a LONG time!

Found something you like? Buy a stock of it to last you a long time is all I can suggest!

:D

Ducatista47
11-05-2006, 12:17 PM
Nice advice, Scotty. I should have added that while some NOS tubes, like WE 300B's, are not tempting at the prices offered, the 6P14P-EV is still plentiful. I bagged matched quads for the same or less, including shipping, as two matched pairs of current offerings, at least at local price comparisons.

I got two quads, wish I could have afforded more. At least they are expected to last 5000 hours each.

Guess I could mention I also picked up two 6N1P's which ended up being ancient Orel pieces. Have not had time to try them yet. I don't expect them to be as good as my Sovtek dash EB's, but they were almost free and shipping was already a done deal.

Clark

Hoerninger
11-05-2006, 12:26 PM
May be it's of interest:
The 6P15P can be used instead of the 6P14P. You only have to care that PIN 1 is used for g1. It's said that it sounds warmer.
(Data sheets are attached).
____________
Peter

Ducatista47
11-05-2006, 12:35 PM
May be it's of interest:
The 6P15P can be used instead of the 6P14P. You only have to care that PIN 1 is used for g1. It's said that it sounds warmer.
(Data sheets are attached).
____________
Peter

Thank you, Peter. I'll look over the sheets. If I can find 6P15P-EV's I will give them a try.

Let me generally recommend, highly, this tool: http://www.duncanamps.com/tdslpe/
It is free, very easy to use, and the data sheet links are fantastic. The .exe file is tiny.
Download at the bottom of the page, then update the file when it starts.

Clark

scott fitlin
11-05-2006, 12:46 PM
All I know is it amazes me at the quality of things made decades ago.

Once I started using vintage tubes, there was absolutely NO going back.

My ears tell me some of the things from the past, well, they really had it right.

I LOVE vintage tubes.

GordonW
11-06-2006, 06:57 AM
The long warmup may be a sign of future trouble...

IIRC, 6P14s and 7189s have slightly MORE heater current draw than standard EL84s. Don't know if it's ENOUGH more to cause a problem, but what you're describing, sounds a LOT like low heater voltage... which would be EXACTLY what would be happening, if there was too much draw. And the output tubes would be the first ones to be affected... pre-amp tubes have more "leeway" on heater voltage, than power tubes.

Ducatista47
11-06-2006, 02:37 PM
Thank you, Gordon, that is very interesting. I have the luxury for the moment to ask the amp's designer about this issue, so I will do so.

If low heater voltage is what is going on, and I don't doubt your observation for a second, he may have a workaround.

The only complication in all this is my CD player. It's a JoLida with tube output, and if past history is any indication, it may share in the blame here.

Clark in Peoria

alexkerhead
11-06-2006, 06:30 PM
It is common for NOS tubes to have better tonality than newly made tubes.
Most tubes, said or relabeled are made for guitar amps these days and the sound(lack of) defintely shows when used in music amps.

Glad you found good tubes, it is definetely not easy.

I have a small Admiral 2xEL84 amp and I had a lot of trouble finding good tubes until I found some NOS military grade tubes, and it sounds great now.

spkrman57
11-06-2006, 07:08 PM
I have found the Russian Electro Harmonix EL84 to sound quite good in my Almorro A205 single ended pentode.

Just my 2 cents !

Ron

Ducatista47
11-06-2006, 09:19 PM
I have found the Russian Electro Harmonix EL84 to sound quite good in my Almorro A205 single ended pentode.

Just my 2 cents !

Ron

They are very good tubes. A lot of listeners think the JJ's are the best sounding, but I like the E H tubes much better. All I'm saying is that in my amp the E H tubes were blown away by the old Soviet military spec tube. I just hope they don't destroy the amp...

Sounds like you are a fellow tubehead with a really sweet amp! :applaud:

Clark

GordonW
11-07-2006, 10:47 AM
Thank you, Gordon, that is very interesting. I have the luxury for the moment to ask the amp's designer about this issue, so I will do so.

If low heater voltage is what is going on, and I don't doubt your observation for a second, he may have a workaround.

The only complication in all this is my CD player. It's a JoLida with tube output, and if past history is any indication, it may share in the blame here.

Clark in Peoria

I think I'm about to have an occasion to test this theory... got a Lafayette LR800 tube receiver here, that used 7189s. We're about to order Ruby Tubes EL84MRs (basically 6P14s) for it, for a budget rebuild. Should get to test those tubes against normal EL84 and such, as for heater draw (just disconnect the B+ voltage, and test the heater current, with each of the three tubes, 7189, EL84 and 6P14)...

If I can get the tech to do this for me while he's fixing the LR800, I'll do it...

Regards,
Gordon.

moldyoldy
11-07-2006, 03:56 PM
....snip.....The (http://The) bad news is that guitar amps are burning up NOS tubes at a furious rate......

Clark in Peoria

Hi, Clark,

In defense of my fellow musicians, couldn't you just say NOS supplies are drying up rather than blame it on the pickers? In the case of EL84s, they're way more common in hifi apps than MI anyway, an EL84 MI amp is a pretty rare bird. After all, tube harmonic distortion is considered an absolute necessity by many musicians including myself, while audiophiles can easily do without it (and by technical definition should). I don't think you'd find listening to music produced entirely by SS gear through a tube amp in your living room to be very satisfactory at all.

I'll see how many spare NOS El84s I have, and will send them to you as I've only one amp that uses them. It could take awhile though, as I have more tubes than time.

I feel much better now....carry on!

FenderBender in the dark

spkrman57
11-07-2006, 04:08 PM
They are very good tubes. A lot of listeners think the JJ's are the best sounding, but I like the E H tubes much better. All I'm saying is that in my amp the E H tubes were blown away by the old Soviet military spec tube. I just hope they don't destroy the amp...

Sounds like you are a fellow tubehead with a really sweet amp! :applaud:

Clark

Most of my friends like JJ/Tesla while I don't. You have to be happy with what works for you!

Almorro single ended pentode is only 5 watts(3 really good watts/chnl). But it sounds good enough for most 97db or more efficient speakers.

I just found a mint MC225 and sent it to Terry DeWick for total checkout and having all the necessary work done to make it good or better than new!

Can't wait to try it out on the 240Ti's I will have soon!

The Russian tubes referenced in this thread did not work well for me, but could be the design of the amp also!

Regards, Ron

Ducatista47
11-07-2006, 08:13 PM
Hi, Clark,

In defense of my fellow musicians, couldn't you just say NOS supplies are drying up rather than blame it on the pickers? In the case of EL84s, they're way more common in hifi apps than MI anyway, an EL84 MI amp is a pretty rare bird. After all, tube harmonic distortion is considered an absolute necessity by many musicians including myself, while audiophiles can easily do without it (and by technical definition should). I don't think you'd find listening to music produced entirely by SS gear through a tube amp in your living room to be very satisfactory at all.

I'll see how many spare NOS El84s I have, and will send them to you as I've only one amp that uses them. It could take awhile though, as I have more tubes than time.

I feel much better now....carry on!

FenderBender in the dark

Moldy,

You are preaching to the choir here. I have a 1977 Mesa Boogie 100/50 watt with graphic, Hammond spring reverb, export transformer and all. Bought new, and I still have the corespondence from Randall and Rayven Smith, including the hand drawn schematic I asked for. When I say I'm into tubes, I mean into tubes. No one in their right mind wants to hear ss distortion.

I just don't think that tubes which are destined to deliberately distort need to be the very tubes which will yield the sweetest undistorted tone on the planet. And shouldn't be. NOS tubes for music reproduction are a very finite resource. Being able to take more punishment before failing is a very different criteria from producing accurate but musical reproduction in the home. On that basis I think NOS audio tubes are partially wasted when used for musical instrument amps destined for distortion. The NOS tubes can do either job well, but newer tubes can not do justice to SET amps when the best possible stable performance is called for.

I have no personal need to deprive any particular individual of their prized old tubes, but I do thank you for your offer. In fact, I wouldn't dream of taking anyone's tubes, but I would like to lengthen the period in history that they are available for sale. It is the trend that I am unhappy about. A tube that will last for years in hi-fi use could be dead glass and metal in the first leg of a tour. I remember Mick & Keith telling Guitar Player their SVT's were pretty much rebuilt after every night on the tour. That is not good news when it concerns a finite resource.

Clark

scott fitlin
11-08-2006, 11:09 AM
Thats why I use a line level component, with a tube, instead of tube amps. Tubes in line level gear offer the taste of tube flavor, but last a long time.

Amps in my application, long hours, hard use, tubes do not last. And vintage tubes are a finite source, and as many are now learning the joy of vintage tube sound, I see the source drying up even faster.

When it comes to 12AX7A,s Im partial to Amperex and RCA, both are absolutely amazing sounding. The tubes made now, well, I found them to be too much tube coloration, I used Sovtek, JJ, Ruby, and Electro Harmonix.

The old tubes sound natural, clean, and smooth, yet extremely dynamic, in that real sort of way only tubes do. Vocals through my vintage tubes have an acoustic sound, something I have grown very fond of, and Im getting this sound out of CD,s no less. Vinyl can sound absolutely incredible.

They always used to say that McIntosh stopped making tube amps when they did, because they couldnt get good tubes anymore. In my listening comparisons, the new tubes, well, they are tubes, but they dont really sound the way tubes sounded when tubes were really it! I like tubes from the 1960,s!

The right tubes are some powerful magic, at least I think so.

:D

alexkerhead
11-08-2006, 11:59 AM
Like I said earlier, most newer tubes are made for guitar amps and not musical amps.
Even if they do not say so, they are relabeled guitar amp tubes 80% of the time.
I have a pair of Sovteks in on of my tube amps and they are definetely colored with crayons. Best thing todo is find NOS tubes that were designed for old tube amps, tube receivers, and console tube amps.

moldyoldy
11-08-2006, 08:34 PM
Current unlimited ebay search results for el84 nos and 6bq5 nos. Note there's not a single one in Musical Instruments. Not definitive, but a pretty good indicator of who's depleting the NOS supply of this particular tube;

Ducatista47
11-08-2006, 09:21 PM
I was speaking generally about tubes suitable for both home audio and instrument amp use. Your point is well taken about EL84's. I was thinking about Vox AC30's and 15's, but I suppose they are relatively scarce in North America. Perhaps less so in Europe. I sure used to see my share in 1966 on local stages.

Clark

PS In the me be dumbass category, my Mesa amp is a 100 slash 60 watt, not 50. Broke rule one, know thy amp.

moldyoldy
11-08-2006, 10:06 PM
Understood. 6L6s, EL34s, and 6550s would be a different story.;)

Ducatista47
11-09-2006, 07:26 AM
I think I'm about to have an occasion to test this theory... got a Lafayette LR800 tube receiver here, that used 7189s. We're about to order Ruby Tubes EL84MRs (basically 6P14s) for it, for a budget rebuild. Should get to test those tubes against normal EL84 and such, as for heater draw (just disconnect the B+ voltage, and test the heater current, with each of the three tubes, 7189, EL84 and 6P14)...

If I can get the tech to do this for me while he's fixing the LR800, I'll do it...

Regards,
Gordon.

It will be interesting to me too. All the sheets I have found, going back all the way to Mullard, show the EL84, 6P14P-EV and the 6P14P to have the same 6.3v, 760mA specs. The Russian sheets are also listing tolerances for heater current, plus or minus 60mA.

It will be nice to know the reality. Thank you for the information and research! You have forgotten more than I will ever know. As in "He spills more than I drink." ;)

Clark in Peoria

Ducatista47
11-11-2006, 09:59 AM
I should have mentioned for the triode only folks here that pentodes can make truly excellent triodes.

Two of the grids are taken out by wiring them to other tube elements. Usually, one already is. If a circuit is designed for this option, it can be a marriage made in heaven. My Grommes amp has rotary knobs built in for each channel, on the chassis top right next to the tubes, to accomplish the task.

Here is a link to a nice article on the simplicities and complications of the approach, with something to say about EL 84's and EL34's in particular. It is written by a local high end (but sensible) company.
http://www.decware.com/paper16.htm
I think most readers here will find his opinions and observations interesting. It was nice to see efficient speakers equated with "sensible" speakers. Horn guys are going to say "I told you so" about that and an observation about what the ultimate system would be (Steve Schell take note). I think I'm already sorry I posted this...:D

Clark in Peoria

Hoerninger
11-11-2006, 10:12 AM
... that pentodes can make truly excellent triodes.

I would like to agree. I tried it with a Philips mono amp (2 x EL84). It sounded sweet. Max output is reduced, that was not an drawback for me.
____________
Peter

moldyoldy
11-16-2006, 10:52 AM
......Let me generally recommend, highly, this tool: http://www.duncanamps.com/tdslpe/
It is free, very easy to use, and the data sheet links are fantastic.....

As of 08/09/2006, version 1.1 became available if current users want to update. Handier than a used hankie!

Ducatista47
11-16-2006, 01:18 PM
Did you notice the search feature where you can insert parameters and get tube types that will build your design? So cool...
http://http://www.duncanamps.com/tdslpe/

Clark

moldyoldy
11-16-2006, 09:10 PM
Yeah, but haven't needed it yet. Of course, you've entered your EL84 parameters already, any luck? Maybe some obscure but plentiful substitute?

I really don't know why we worry, 2 or 3 sets of good tubes will likely outlast most of us anyway. Seems like I remember talk of 5-10K hours if biased right, but that was over 10K days ago.;)