[Galapac]

I prefer pentode mode myself.
Triode was a bit “soft“ for my tastes In terms of power wheras pentode seems ”bolder”, if that makes sense.

 

[lostrockets]

I prefer pentode mode myself.
Triode was a bit “soft“ for my tastes In terms of power wheras pentode seems ”bolder”, if that makes sense.

Definitely a different sound, what tubes are you using with pentode?

 

[Galapac]

Definitely a different sound, what tubes are you using with pentode?

I mainly use 6L6GC/EL34 varieties with E80CCs up front but I moved my amp to take the E80CCs as they require a bit more power.
The amp runs cool to the touch so I have no issues and have been running this setup for about 5 months now.
My favorite 6L6GC/EL34s are:
Svetlana Winged ==C== EL34 original, not the rebrand.
RCA 6L6GC black plate
Sylvania 6L6GC

Here is a link where I shared what I did to use EL80CCs and 6SN7s.

Post in thread 'Elekit TU-8200 DX Headphone/Speaker Amp Review'
https://www.head-fi.org/threads/elekit-tu-8200-dx-headphone-speaker-amp-review.722633/post-16850879

 

[lostrockets]

anyone compared the winged c to any other el34s or even new production? how about the nos 6L6 to new production?

got some 5881s on the way to try out. also looking for some nos 7581s.

so far my favorite are nos amperex 12au7s with gold lion kt77s

 

[Dimu]

So I finally decided to swap output transformers in my amp which I got from Victor more than a year ago. Really like the sound! If money is no object this one is a recommended upgrade. Also parasitic noises went down to next to nothing. And it fits nicely with my big power transformer.

Separate thanks to Victor for using high quality wire in the transformer upgrade kit. It made a difference.

I've been enjoying this amp for years and I am not planning to stop, it is just awesome! In fact I have a sealed backup unit sitting in the closet

 

[UntilThen]

I see you are using TFK EL12 spez.

I am a fan of using Telefunken EL12 spez in Elekit TU8200. I have 3 pairs of those bought in new original TFK boxes.

Though I have other good tubes such as GEC KT88 and Mullard EL34 double D getters and Tung Sol 6550 1960s, I still return to the EL12 spez very often.

 

[Galapac]

So I finally decided to swap output transformers in my amp which I got from Victor more than a year ago. Really like the sound! If money is no object this one is a recommended upgrade. Also parasitic noises went down to next to nothing. And it fits nicely with my big power transformer.

Separate thanks to Victor for using high quality wire in the transformer upgrade kit. It made a difference.

I've been enjoying this amp for years and I am not planning to stop, it is just awesome! In fact I have a sealed backup unit sitting in the closet

Wow! Long time, no post.
Glad to see you are still among the living.
How would you compare the performance now compared to pre Lundahl?

I did that upgrade first when I bought mine along with your recommended bridge diode upgrade to use the E80CCs and love my TU-8200 with different EL34/6L6GC combinations.

 

[Galapac]

I see you are using TFK EL12 spez.

I am a fan of using Telefunken EL12 spez in Elekit TU8200. I have 3 pairs of those bought in new original TFK boxes.

Though I have other good tubes such as GEC KT88 and Mullard EL34 double D getters and Tung Sol 6550 1960s, I still return to the EL12 spez very often.

Any other recommendation for EL12 spez or is that THE tube to have in that class?
I see also Tungsram in EL12 but not sure of their performance.

I also just built the TU-8600S and using that with WE 300Bs and that is one sweet amp but that is for another thread.

 

[Dimu]

Yes I like EL12 a lot, even though it is not a fit for this amp strictly looking at the datasheet. But it sounds great and I have not had any trouble with it yet. My other big favorite is GEC TT21 which is similar to KT88. But I had trouble with a pair of TT21 after a while. GEC KT66 is very nice too. I don’t like EL34 sound, 6L6 sounds better to my ear. Never tried TungSol but I would imagine I would like it. Tried some other tubes but nothing else is noticeably better than 6L6. So EL12, TT21/KT88 and KT66 are my favorites. And I don’t buy any tubes that are not at least 40 years old, most of my EL12 are from 1954. EL12 is a good thermal fit for this amp, it runs much cooler than with big tubes like TT21.

More important than output tube is E80CC input tube. I would take E80CC with 6L6 over any output tube with 12AU7. And as you can see in the pictures I power the whole thing from a beefed up transformer (not just higher current rating but bigger magnetic core) with additional caps for smooth power delivery with ample on-demand capacity. And all other components are upgraded including all caps, almost all resistors, and the pot. And soldered with lots of lead and silver throughout.

I mostly use the amp with Schiit Gungnir Multibit with USB buffer. And 8500 with Mullard 12AT7 in between, cranked up to boost second harmonic. When I use turn table it is hooked up via 8500 too which has significantly upgraded phono section.

 

[Dimu]

Wow! Long time, no post.
Glad to see you are still among the living.
How would you compare the performance now compared to pre Lundahl?

I did that upgrade first when I bought mine along with your recommended bridge diode upgrade to use the E80CCs and love my TU-8200 with different EL34/6L6GC combinations.

I think Lundahl is an improvement, I am definitely keeping mine. It was just about the only stock component I had left in my amp- everything else is not what came in the kit from Japan. I know Victor had worked a lot on making it happen, he tried different prototypes before he finally got it working well. And then he did this great job of figuring out a bracket, PCB and good quality wires.

I travelled a lot over last couple years so spent little time near the amp and did not have a chance to upgrade transformers until today. Actually I opened it up to deal with D7 rectifier problem and at the same time decided to throw in the transformers. If you check the pictures you will see I mounted it differently than Victor’s pictures suggest, I did that in order to minimize cable lengths. So my left transformer is oriented same way as right so that secondary is facing backwards.

As for D7 I have ordered an 8 amp part to try because my 3 amp part does not seem to be too happy after a while.

 

[UntilThen]

Any other recommendation for EL12 spez or is that THE tube to have in that class?
I see also Tungsram in EL12 but not sure of their performance.

I also just built the TU-8600S and using that with WE 300Bs and that is one sweet amp but that is for another thread.

I have not tried EL12 without the top anode cap.

I have tried Radiotron 807 which is good but not as good as EL12 spez.

Woo Audio offered to make the Teflon adapters for me and I might consider it because their adapters are just superb.

 

[Dimu]

I have not tried EL12 without the top anode cap.

I have tried Radiotron 807 which is good but not as good as EL12 spez.

Woo Audio offered to make the Teflon adapters for me and I might consider it because their adapters are just superb.

You cannot just stick tubes in without checking datasheet for compatibility. EL12 without top anode is not rated for anode voltage produced by 8200. EL12 spez has much higher voltage rating which is compatible with the amp. The problem with it is oscillations at around 1MHz. I’ll play with it to see if I can suppress it because other than that it is a really great match for the amp.

 

[jerick70]

EL12 looks interesting. I may try them, but I’m super happy with my Tungsol 7581As and Siemens E80CCs.

If I was going to spend more money on tubes, I think I would build the 300b amp and get some top end 300b tubes.

 

[UntilThen]

You cannot just stick tubes in without checking datasheet for compatibility. EL12 without top anode is not rated for anode voltage produced by 8200. EL12 spez has much higher voltage rating which is compatible with the amp. The problem with it is oscillations at around 1MHz. I’ll play with it to see if I can suppress it because other than that it is a really great match for the amp.

Yes I’m aware of that. That’s why I have stayed off EL12 but kept with EL12 spez.

In any case, EL12 spez is custom build for my tube amp and that’s not an Elekit.

 

[Dimu]

You cannot just stick tubes in without checking datasheet for compatibility. EL12 without top anode is not rated for anode voltage produced by 8200. EL12 spez has much higher voltage rating which is compatible with the amp. The problem with it is oscillations at around 1MHz. I’ll play with it to see if I can suppress it because other than that it is a really great match for the amp.

Checked those oscillations and confirmed that with Lundahl, E80CC and EL12 spez there are no high frequency oscillations. The only signals I see at 500KHz and above are present with amp disconnected from power, so these are induced from external fields.