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Dark Voice 339 - Page 115

post #1711 of 2364
Quote:
Originally Posted by Contrails View Post

Nice.

What DAC is everyone else using? I am using HRT MS2. I was thinking of upgrading to Audio-gd NFB 3.2 Any other recommenations around that price that go well with the 339 and he500?

At this moment i use my hm602 as my source..i use the line out so it bypasses its internal amping!.its excellent!

 

But am now looking into somthing better for my 337..am waiting for a quote for a very special one of a kind custommade dac-amp combo..an all in one enclosure (two of their products combined into one) with an external HUGE powersupply...and then i will be selling both my hm602 and 337..but first the right price..waiting is killing me!

but i understand the natural sounding metrum octave dac goes very well with a tube amp..like the 337 or 339. And nowthey have version mk2..with usb now.

post #1712 of 2364
Quote:
Originally Posted by telecaster View Post

 

It is great news that twisting heater wiring improve hum with EF800, that's the only reason why I didn't like the EF80/EF800, because they sound absolutely fabulous in the amp!

I tested my EF80 mullard and TFK EF800 and they DO sound good! Such bass that is thunderous and dynamic, with neverending highs. I only dislike the hum I get and maybe after prolonged time of listenning a small degree of listenning fatigue due to the dynamic nature of the sound presentation.

 

I will replace the heater wire ^^

 

Wall-E, you're the man!

 

About the bias voltage, it seems you are running the bias on the hot side. As it applied to the cathode, if I understand correctly, it is then a negative votage.

The more the tension is near zero, the hotter the bias is, and the more current is going to the plates. If you're bias point was -2.18V, and you are running at -1.85V, you run the tubes with a hot bias, and you should have very dynamic sound, improved gain and lowered distorsion, but it "could" (that I don't know) lessen the ltubes life and be fatiguing on the transformaters.

 

As it is if you didn't experience ill effect, or didn't saw the tube plate going red, then your bias is not that hot.

 

While the soldering gun was at reach, I rewired the EF80 adapter so I can use my EF800 directly with my modded 6J5 driver 339...

You're absolutely right!

The cathode resistor is the component that determines plate current.The plate resistor(30 or 33K) is selected to obtain required gain and plate voltage
when the bias voltage is small it cause more anode current to flow, making the tube physically hot if this max level is exceeded for too long the anode will glow deep red and eventually melt, but this not gonna happen! you can control the current by measure the voltage drops across plate resistor and divide this by plate resistor in ohm so with my battery biased cathode (1.805V) for (EF800/6as7g) voltage drop across plate resistor(33K) is 52.5V, so let's count it 52.5 : 33000 = 1.59mA this is how "hot" actually cold biased it is, in the same way measure the cathode follower power tube the measured voltage drop on the cathode resistor is 90V, 90 : 470 = 191mA, as the twin triode are connected in parallel the current is 95.5mA for each half which is hot but still below the (6as7g) maximum 125mA.

 

Have to do the same with my adapters, my ef 80/800 were lying in the drawer since July because the hum issue but now problem solved, maybe make another one with better parts?

How was the 6SJ7adapter project? u had some small trouble isn't it and a bit of bad luck too wink.gif, the adapters looks adorable, good job!


Edited by WALL-E - 3/24/13 at 11:16am
post #1713 of 2364

So, I've been watching this thread for a while and considering purchase of a 339 for some little time, waiting for dust to settle on issues and opinions....

my gear addiction for the tubies is starting to wear thin and I'm about ready to pop open the wallet once again, LOL.blink.gif

 

I guess this thread is where I might get the best considered response on where best to purchase the 339?

 

I'm having a tough time making the decision between the Woo WA7 vs the La Figaro 339.

Any recent opinions about that comparison?

 

 

Thanks, fellas!

smile.gif

post #1714 of 2364
Quote:
Originally Posted by WALL-E View Post

You're absolutely right!

The cathode resistor is the component that determines plate current.The plate resistor(30 or 33K) is selected to obtain required gain and plate voltage
when the bias voltage is small it cause more anode current to flow, making the tube physically hot if this max level is exceeded for too long the anode will glow deep red and eventually melt, but this not gonna happen! you can control the current by measure the voltage drops across plate resistor and divide this by plate resistor in ohm so with my battery biased cathode (1.805V) for (EF800/6as7g) voltage drop across plate resistor(33K) is 52.5V, so let's count it 52.5 : 33000 = 1.59mA this is how "hot" actually cold biased it is, in the same way measure the cathode follower power tube the measured voltage drop on the cathode resistor is 90V, 90 : 470 = 191mA, as the twin triode are connected in parallel the current is 95.5mA for each half which is hot but still below the (6as7g) maximum 125mA.

 

Have to do the same with my adapters, my ef 80/800 were lying in the drawer since July because the hum issue but now problem solved, maybe make another one with better parts?

How was the 6SJ7adapter project? u had some small trouble isn't it and a bit of bad luck too wink.gif, the adapters looks adorable, good job!

Great info about the bias and how the current plate are fed in those tubes!

I know this can sound crazy but I am running a 25K plate resistor because I prefer the sound vs the 33K. I will take measurements before going battery bias for sure! All my tubes sounds beautiful that way except for the combination EF800 with cetron 7236 that seems edgy and incredibly speedy, maybe too much or so it seems to my ears.

 

The EF800 and GE6AS7G sound absolutely crazy! EF800 with GEC6080WA is to die for in term of musicality and depth, bass is articulate...

 

I rewired the heater to tight twisted, I also change all the modulation thin grey cable Inside the 339, including the small wire that goes to the power tube, with very thick and double screened Sommer cable. Now I don't have any hum with Telefunken EF800 and I just bought spares cause this tube is absolutely crazy good (slightly better than mullard EF80) in the 339!

 

Also I did a mod that I tought was not important but revealed itself beautiful it is to switch the green led to blue ones! It way more attractive looking that way hehe ^^

 

The 6SJ7 adapter is done, I have a spare ceramic tube base with teflon socket and I plan to make a 6J7 tube adapter just for fun. I want to know how the old tube sounds like, especially the pentode made for RF, the EF37A. It should look pretty cool with the wired grid cap on top of the tube!


Edited by telecaster - 3/24/13 at 4:20pm
post #1715 of 2364

Dogmeat,

 

What headphones do you have? Hd650/he500 would pair well the LF339.  Headfonia have done a nice review of the LF339.  

 

Also, I would recommend buying directly from yuking09.com 

post #1716 of 2364

How would you guys rate the

 

Red 5698 , EFK EF80 and the 6SJ7gt TS?

 

For 6SJ7gt TS, is this the only best for this type of tube? 

 

Thanks

post #1717 of 2364
Quote:
Originally Posted by telecaster View Post

Great info about the bias and how the current plate are fed in those tubes!

I know this can sound crazy but I am running a 25K plate resistor because I prefer the sound vs the 33K. I will take measurements before going battery bias for sure! All my tubes sounds beautiful that way except for the combination EF800 with cetron 7236 that seems edgy and incredibly speedy, maybe too much or so it seems to my ears.

 

The EF800 and GE6AS7G sound absolutely crazy! EF800 with GEC6080WA is to die for in term of musicality and depth, bass is articulate...

 

I rewired the heater to tight twisted, I also change all the modulation thin grey cable Inside the 339, including the small wire that goes to the power tube, with very thick and double screened Sommer cable. Now I don't have any hum with Telefunken EF800 and I just bought spares cause this tube is absolutely crazy good (slightly better than mullard EF80) in the 339!

 

Also I did a mod that I tought was not important but revealed itself beautiful it is to switch the green led to blue ones! It way more attractive looking that way hehe ^^

 

The 6SJ7 adapter is done, I have a spare ceramic tube base with teflon socket and I plan to make a 6J7 tube adapter just for fun. I want to know how the old tube sounds like, especially the pentode made for RF, the EF37A. It should look pretty cool with the wired grid cap on top of the tube!

Sorry are you referring to the EF80 instead of the EF800?

 

The 339 need tube biasing??

 

Thanks

post #1718 of 2364
Quote:
Originally Posted by snip3r77 View Post

How would you guys rate the

 

Red 5698 , EFK EF80 and the 6SJ7gt TS?

 

For 6SJ7gt TS, is this the only best for this type of tube? 

 

Thanks

 

Check the previous pages, it's all been done

post #1719 of 2364

EF800 is a better long lasting version of the EF80 made by telefunken.

post #1720 of 2364
Quote:
Originally Posted by Ultrainferno View Post

 

Check the previous pages, it's all been done

+1, lots of uselfull information in this thread, take the time to read it all...

post #1721 of 2364

I have been using my HD280s as the testing headphones before I plug in new tubes.  I put the RCA 6AS7G and 5693s in and listening to my HD280, wow! The bass is insane! What other headphones have you guys been using with amp besides HD650 and He500. 

post #1722 of 2364

All of them :D

post #1723 of 2364
Quote:
Originally Posted by snip3r77 View Post

How would you guys rate the

 

Red 5698 , EFK EF80 and the 6SJ7gt TS?

 

For 6SJ7gt TS, is this the only best for this type of tube? 

 

Thanks

I dont think u do a. Bad deal with any if the three..as ultrainferno said..and its been said in this thread a couple of times..ts sj7gt mesh plates are on top of many lists...but ofcourse it all depends on ur preferences of sound..

post #1724 of 2364
I emailed them a list. Hopefully they reply soon.

Are they fast with replies?
Quote:
Originally Posted by Contrails View Post

Snip3r77, vacuumtubes.com have 5998 for sale. They should have the other tubes as well. You can also try thetubestore.com. I usually just google the name of the tube and then visit the websites.
post #1725 of 2364
Redundant posr
Edited by snip3r77 - 3/25/13 at 9:53am
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