[GDuss]

Right on! A $5.00 tube that slaps ya in the face!

Love it!!

Yep, that's pretty much what happened last night.

 

[GDuss]

If you like them and they are cheap....buy a few...they won't go bad.

In some cases the shipping is more than the tube!!!

Sometimes silence is the best thing, until you have all of those tubes that you want of course

I'm shutting up now for real.

 

[DecentLevi]

In case anyone may want to try GEC KT66, here seems like an especially good deal
https://www.canuckaudiomart.com/details/649564801-2-vintage-gec-kt66-output-tubes/images/2456118/

 

[JazzVinyl]

Any brand preferences on the 6BL7s?

The regular GE's are great. Older Sylvania "Flat Plates" tend to develop noises (hard to find good ones), but later Sylvania's are fine. Many brands are actually GE re-brands...

 

[L0rdGwyn]

Jupiter caps are in. The 82K resistors run underneath the caps, there is a terminal below them so the resistors have a path to ground, I folded over two of the top lugs and covered them with heatshrink to use as anchors for the caps with zip ties. Worked out really well, the caps are too heavy on their own.

Hard to say definitively, but I do feel there is more air and space with the Jupiters, not going to swap these out like I did the resistors! Regardless, very happy with them and the audible changes my modifications have made so far

Last but not least will be to rectify and filter the AC to DC for the driver filaments. Would have considered doing it today, but the mail was delivered late and probably better to break up the work anyway, won't get to it until Monday or Tuesday.

 

[JazzVinyl]

Jupiter caps are in. The 82K resistors run underneath the caps, there is a terminal below them so the resistors have a path to ground, I folded over two of the top lugs and covered them with heatshrink to use as anchors for the caps with zip ties. Worked out really well, the caps are too heavy on their own.

Hard to say definitively, but I do feel there is more air and space with the Jupiters, not going to swap these out like I did the resistors! Regardless, very happy with them and the audible changes my modifications have made so far

Last but not least will be to rectify and filter the AC to DC for the driver filaments. Would have considered doing it today, but the mail was delivered late and probably better to break up the work anyway, won't get to it until Monday or Tuesday.

Oh! The Jupiters replaced the Russian 'Paper In Oil' caps?

Appears to be another successful surgery, doctor! Excellent work!

On the DC heater change...can you rectify 1/2 wave DC? You have some AC and some DC there. Maybe you can, just never thought of trying that. And the Voltage Drop, will not be too much?

Again...Great Job, LG!!

 

[Monsterzero]

In case anyone may want to try GEC KT66, here seems like an especially good deal
https://www.canuckaudiomart.com/details/649564801-2-vintage-gec-kt66-output-tubes/images/2456118/

I got excited there for a minute. Theyre of different constructions. No idea how different they sound from one another,but I think I'd prefer a pair of the same construction. Good price though.

 

[leftside]

LOL...no problem GDuss...
6N7 is a dual triode as the 6SN7/12SN7/12SL7's are. But they have a "common cathode". The others have a cathode/grid/anode for each triode. 6N7 has two grids, two anodes but one cathode.
So does the ECC31 tube. 6N7 requires an adapter due to the common cathode. 6N7 has an amplification factor of 35, 6SN7 is 20 and 6SL7 is 70.

https://frank.pocnet.net/sheets/127/6/6N7.pdf

You can see one pin labeled "K" for both cathodes.

Compare that to 6SN7 datasheet:

https://frank.pocnet.net/sheets/127/6/6SN7GT.pdf

Two pins are labeled K (cathode).

6N7 is a good sounding tube in the GOTL...I am going to try a Deyan made adapter to put 2x 6N7's in the SN7 socket, one for L and one for R, to see if the stage benefits from separate bottles.

My upcoming amp will be able to take the 6N7 in the 6J5 sockets. Ships next week. I should be able to compare two 6N7's (in the 6J5 sockets) vs a single 6N7 (in the 6SN7 socket with an adapter).

 

[mordy]

Should be interesting to hear if there is a difference in sound.

 

[JazzVinyl]

My upcoming amp will be able to take the 6N7 in the 6J5 sockets. Ships next week. I should be able to compare two 6N7's (in the 6J5 sockets) vs a single 6N7 (in the 6SN7 socket with an adapter).

That sounds great LS...!!

What powers in the new amp...er....what is the rest of the configuration?

Cheers!!

 

[DecentLevi]

Well the 6N7 has won me over. I guess I should shut up about it and buy more while they're still cheap.

I'll mention again that (at least on F.A. amps), I really prefer the RCA over Ken-Rad 6N7 black metal tubes, for a more of a natural tone and realistic bass vs. somewhat extra lush with the K-R's, but this too may vary on Glenn amps. I still have both to compare later when mine arrives.

I regret nothing!

So, here is the lowdown on the resistors. The four I had to try were the Kiwame carbon film, TKD metal film, Vishay metal film, and Audio Note tantalum nitride thin film. As I got started, I decided I just didn't have it in me to swap all of these resistors in one sitting, so I'd do an abbreviated A-B for now and started with the Kiwame (since I had read much about them on DIY Audio forum), then I would put in the Audio Note tantalum, I figured these were the most expensive so I might as well keep them in the amp, not expecting to hear an undeniable difference...

Got listening to the Kiwame, "hmm, this sounds pretty darn good, smooth, laid back, spacious, and satisfying" I thought to myself, not really attributing any of it to the resistors. Went and swapped in the Audio Note tantalums in much more permanent fashion, clipped the ends and everything. Came back in to settle down, and immediately felt something was lost. The sound was brighter, more aggressive, a little less spacious, albeit probably more revealing.

At this point, pretty far into the afternoon having not eaten lunch, thought it could be my ears/brain playing tricks, but I had to be sure. So I ate, put the Kiwames back in, but left the Audio Note with one end attached for the sake of easily swapping one for the other. Sure enough, with the Kiwames back in place, my sense of satisfaction with the sound returned. I made this swap three or four more times with the same results, the Kiwames despite being $1 compared to $18 for the Audio Note (uh yeah, I spent $18 on a resistor) have a smoother, warmer, more laid back sound. The tantalums are brighter, more aggressive, and less spacious to my ears. I feel very confident at this point this was not some placebo, I expected the Audio Note resistors to be better.

So, apparently the 22K resistors do matter and do change the sound. Of note, the Kiwame are carbon film and 5W, the Audio Notes are tantalum nitride and 2W. Those crazy guys on DIY Audio were right...

Edit: wow, rereading this post, what I am hearing aligns very well with what Dsavitsk had said about the Kiwame versus metal films in two identical circuits. Never thought there was anything to this, I'm a bit shocked.

https://www.head-fi.org/threads/carbon-film-vs-metal-film-revisited.121104/

Hmmm, @2359glenn have you ever tried the Kiwame carbon film resistors in your amps - provided any compatibility? And LG this didn't mention if you compared the TKD and Vishay resistors.

 

[leftside]

That sounds great LS...!!

What powers in the new amp...er....what is the rest of the configuration?

Cheers!!

I'll create a separate thread after I've been listening to it for a week or so, but basically.
- Two chassis (power and amp)
- Can take 2-6 power tubes. 5998/6AS7 selector switch
- Drivers: 2 * 6J5 or 2 * C3g or 1 * 6SN7. Selector switch for these tubes and also 6SL7, 12SL7 and 12SN7.

 

[JazzVinyl]

I'll create a separate thread after I've been listening to it for a week or so, but basically.
- Two chassis (power and amp)
- Can take 2-6 power tubes. 5998/6AS7 selector switch
- Drivers: 2 * 6J5 or 2 * C3g or 1 * 6SN7. Selector switch for these tubes and also 6SL7, 12SL7 and 12SN7.

Sounds good!! I say keep the content here!

 

[L0rdGwyn]

And LG this didn't mention if you compared the TKD and Vishay resistors.

Yes, I did not get to them, too much to do in one days work, swap the caps, replace the resistors, also redid the wiring for the driver filaments. At some point, I will get some alligator clips and probably a few more resistors to try, will make for a much more rapid A-B comparison, quite interested now that I have heard a difference. Very possible though the audible change is more related to the resistor material than the particular brand.

I think the Lampizator DAC is also contributing, but with the changes I've made, resistors caps and otherwise, my GOTL has taken a decidedly warm and smooth turn sonically, and I am really enjoying it, sounds very natural to me.

 

[DecentLevi]

There is more to come @DecentLevi has ordered all the adapters in existence.

Not every adapter, just these, (LOL)
- (1x) MHLD6 / CV1101 to 6SN7 adapter
- (1x) Dual 6J5 to 6SN7 adapter
- (2x) EL11 to 6SN7 adapters
- (2x) EL12 Spez to KT66 adapters
- (4x) EL12 to KT66 adapters
- (4x) EL3N to KT66 adapters
- (4x) EL38 to KT66 adapters
- (4x) EL39 to KT66 adapters
- 2X ECC88 / 6N23P to 6SN7
- 1x 6N7 (VT-96) to 6SN7

Deyan thus far has been superb to work with. He assures me he has top quality materials (much silver and no brass or nickel crap) and he offered a reasonable package deal on the above. I was told I can also use the 6N23P, E88CC, 6CG7 in the ECC88 adapter and the EL32 adapter has to be dual, like the 6J5 / L63 / 6C5 adapters, as well as EL11. Luckily EL34 and KT(xx) series don't need adapters on my upcoming amp.

Although I have heard something about EL34 and KT66 being wired different?