[telecaster]

Maybe try other ef86?

About the hum in noisy driver, anyone is brave enough to try this mod?
It's about the noise induce in the drivers by the heaters power.

1. Creating a virtual center tap
2.Elevating the reference of the heater voltage

https://www.head-fi.org/threads/darkvoice-336i-336se-tuberolling-partii.348833/post-16182719

I know it is performed on the 336se, but the idea should be the same for the 339.

I for sure will try his diode mods on the 6as7g socket in Order to slow start the filament heating. But it's another mod that the hum noise mode. It's for protection g tubes from arcing.

I tried the elevated heater, the hum is now minimum of the minimum, and should never be a problem anymore for me.
Super happy!

It is still not still tombstone silent when volume pot is wide open, but it's pretty much as good as can be. Practically hum is now a non issue for the 339. But looking at others testimonies, hum never was a problem for 339 users to begin with!

This mod just reduces it drastically ^^

I advise for the novice to only do the center tap mod, as it is a huge improvement over the stock heater noise.

Here is a photo. Just follow the guide : https://www.head-fi.org/threads/darkvoice-336i-336se-tuberolling-partii.348833/post-16182719
You need to make sure to disconnect the heater from the ground at the driver socket.
And no need to disconnect or change the led at all.

And here is the elevated heater in my amp :
I also wire a diode in the 6080 socket in order to protect the tube from arcing. It's a like a time on the B+ while the heater is heating the filament if I understand correctly.

So on the photo above, the 100K resistor and negative leg of the 10uf green cap is connected on the ground bus. You can see both 100ohm blue little resistors on the heaters, and the big red carbon resistors is the 220K connected to the + lug of the second last power cap.

Just for information the B+ is around 140V at the second last cap and the elevation is 40V

 

[bpiotrow13]

@telecaster wow, not sure if I am able to fully understand, but this is really unique knowledge!

 

[L0rdGwyn]

I tried the elevated heater, the hum is now minimum of the minimum, and should never be a problem anymore for me.
Super happy!

It is still not still tombstone silent when volume pot is wide open, but it's pretty much as good as can be. Practically hum is now a non issue for the 339. But looking at others testimonies, hum never was a problem for 339 users to begin with!

This mod just reduces it drastically ^^

I advise for the novice to only do the center tap mod, as it is a huge improvement over the stock heater noise.

Here is a photo. Just follow the guide : https://www.head-fi.org/threads/darkvoice-336i-336se-tuberolling-partii.348833/post-16182719
You need to make sure to disconnect the heater from the ground at the driver socket.
And no need to disconnect or change the led at all.

And here is the elevated heater in my amp :
I also wire a diode in the 6080 socket in order to protect the tube from arcing. It's a like a time on the B+ while the heater is heating the filament if I understand correctly.

So on the photo above, the 100K resistor and negative leg of the 10uf green cap is connected on the ground bus. You can see both 100ohm blue little resistors on the heaters, and the big red carbon resistors is the 220K connected to the + lug of the second last power cap.

Just for information the B+ is around 140V at the second last cap and the elevation is 40V

Nice job @telecaster , glad it worked out.

 

[telecaster]

Nice job @telecaster , glad it worked out.

Thanks to you for offering such a nice and cheap upgrade for all of us!

 

[MJS242]

A long time ago I bought some tubes and the packaging included this foam holder. I was never sure what it was called, but I always liked putting tubes on it.

Recently I discovered it's a test tube /vial holder and you can buy them on ebay (maybe you guys know about this).

This one you can find here:

https://www.ebay.com/itm/Vial-Organ...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

This is perfect for those of you that like to listen to tubes and not music, or maybe you just want to show off your unhealthy tube buying problem.

 

[hp4fun]

A long time ago I bought some tubes and the packaging included this foam holder. I was never sure what it was called, but I always liked putting tubes on it.



Recently I discovered it's a test tube /vial holder and you can buy them on ebay (maybe you guys know about this).



This one you can find here:

https://www.ebay.com/itm/Vial-Organizer-Storage-Rack-Foam-Stand-24mm-Diameter-Holder-25-Hole/353320528483?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

This is perfect for those of you that like to listen to tubes and not music, or maybe you just want to show off your unhealthy tube buying problem.

Need FDA approval?? or emergency use only.

 

[jonathan c]

This is perfect for those of you that like to listen to tubes and not music, or maybe you just want to show off your unhealthy tube buying problem.

Is there a way that I can listen to the tube without amplification or music?

 

[Galapac]

A long time ago I bought some tubes and the packaging included this foam holder. I was never sure what it was called, but I always liked putting tubes on it.



Recently I discovered it's a test tube /vial holder and you can buy them on ebay (maybe you guys know about this).



This one you can find here:

https://www.ebay.com/itm/Vial-Organizer-Storage-Rack-Foam-Stand-24mm-Diameter-Holder-25-Hole/353320528483?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

This is perfect for those of you that like to listen to tubes and not music, or maybe you just want to show off your unhealthy tube buying problem.

Nice for photos but all my tubes are boxed away except for what I use.

Looks like the Bendix dealer has more than one set and his second set is as high as it was the last day of the previous auction. Will it go higher? Tune in next week folks!
https://www.ebay.com/itm/4-Vintage-...p-Tube-Quad-NIB/313439993061?autorefresh=true

 

[qingcai]

Comparing these two photos...

339



339i



The only obvious change is they have added an additional RC to the B+ filter circuit. In the Darkvoice (and as far as I can tell, the La Figaro 339), the filter goes:

CRCRC-CRC

Which I thought was peculiar as the fourth and fifth capacitors in the filter are directly connect to one another, meaning they are in parallel, meaning the capacitance is additive, there is no filter. I wondered to myself "why didn't they throw a resistor between the two to decouple the capacitors?" There is really no downside, it will just add additional 120Hz noise suppression. Well seems they thought the same thing because they added the resistor so now it goes:

CRCRCRCRC

The mains transformers appear to be larger, so perhaps there is additional B+ and the bias points have been altered? Cannot say without measuring it. They might have altered the output capacitance, but it isn't obvious, can only spot 6.8uF caps but I believe there are others hidden in the center transformer shroud.

By and large though, the circuit is the same.

for 339i, I dont see any wire come from the central transformer. does the central transformer exist ?

thanks

 

[L0rdGwyn]

for 339i, I dont see any wire come from the central transformer. does the central transformer exist ?

thanks

I believe that is where the output capacitors are housed but I have not had the amp in front of me to check myself.

 

[qingcai]

I believe that is where the output capacitors are housed but I have not had the amp in front of me to check myself.

thanks, I just found a picture in massdrop, there are 4 capacitors sit in the middle block.

 

[qingcai]

the guy saying he copied from head-fi. but I did not see it on head-fi .

 

[Galapac]

Post deleted

 

[Galapac]

This thread has been asleep for awhile...time to wake it up...

I got a chance to listen to the TF6080s this weekend and although not a bassy tube which is something I like, the detail retrieval is very strong and to me separation of the instruments seems more pronounced in a front to back emphasis as opposed to left/right separation. I would not consider this a strong tube for rock but would be an excellent choice IMO for classical or jazz if that is what you lean towards to. Clarity is a string point with this tube.

Bonus points for photo ops as this tube shines very bright as the getters seem more exposed compared to other 6080s.

 

[telecaster]

This thread has been asleep for awhile...time to wake it up...



I got a chance to listen to the TF6080s this weekend and although not a bassy tube which is something I like, the detail retrieval is very strong and to me separation of the instruments seems more pronounced in a front to back emphasis as opposed to left/right separation. I would not consider this a strong tube for rock but would be an excellent choice IMO for classical or jazz if that is what you lean towards to. Clarity is a string point with this tube.

Bonus points for photo ops as this tube shines very bright as the getters seem more exposed compared to other 6080s.

Nice! Are they greys or black plates?
I saw a pair going for less than 80 yesterday! For my LCD3 I think they are just the bomb for all gendra of music. I love the details too ^^