Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Little Dot Tube Amps: Vacuum Tube Rolling Guide
New Posts  All Forums:Forum Nav:

Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 238

post #3556 of 7220
Quote:
Originally Posted by MIKELAP View Post
 

So gibosi how are those 6N23P doing thinking of getting some. and i bidded on some Amperex 6DJ8 you suggested the other day.

 

The Reflector 6N23P are really nice tubes. However, they are a bit brighter than the Amperex ECC88, and a little too bright for my taste. But others, who prefer a brighter sound, would like these. And this morning, I finished burning in the Tesla PCC88. These too are very nice tubes, quite similar to the Amperex, but I think the Amperex flow a bit better. That is, the Amperex are a bit more liquid and fluid than the Tesla. So for now, the Amperex are my favorite, and then, Tesla, Reflector, Mullard and Siemens. 

post #3557 of 7220

Alright, while everyone's now officially jumped onto the ECC88 bandwagon, I'm still investigating the -just as expensive- ECC83 family (12AX7).

 

Since I proved that these tubes do miracles in my amp, I figured I might as well skip beating around the bush right away (not buy a gazillion $8 tubes and just watch them pile up and never be used) and get the best tube I could in that family directly! If the best doesn't cut it, then the whole family gets publicly shamed. So yeah... I got a Telefunken ECC83/12AX7. And even though I got a "good" deal on it, I'm won't say how much I paid for it lol!

 

The thing is that the Telefunken 12AX7 tubes aren't rare, but there are like no NOS ones anymore, so people just keep exchanging the same old tubes, and those are just getting weaker and weaker every year... Most of ebay buys or sells pairs that barely test in the good range for $100! It is the land of dubious tube tester results and always-different-values, a land I hadn't known before. Granted, those Telefunken tubes have the reputation of lasting forever -hence the sheer number of used ones available- and even a weak tube can last a lifetime (I've seen the 100000 hours figure a few times, yes that's five zeros).

 

So basically, I paid a bit extra (again, still an OK deal) to get a very strong -stronger than the nominal "new" values which is still less than the actual "new" values- tube with good silk writing, and from the best time and place: Tele ECC83 made in Berlin around 1960 with ribbed plates and a small logo. I figure I could always sell it for more than what I paid for it anyways, so it's not like it's money lost...

 

What saddens me is that I'm going to run into the exact same problem with the ECC88/6DJ8 family lol... Yeah, you can get single or pairs of orange globe Amperex for decent prices, but not strong or close to NOS, with a good guarantee of what you're buying or with a good resell value. A pair of Philips Holland ECC88 I'd been looking at on ebay this weekend (tested strong, equivalent to late 60s orange globes) was eventually sold for almost $60! That's just too much for basic used tubes that don't even carry some symbolic brand name like Amp'ex, "Bugle Boys", Telefunken or whatever...

 

Anyway, the hunt is on, I guess; but I may be done with the "3 pairs every week" craziness lol!

post #3558 of 7220
Quote:
Originally Posted by Audiofanboy View Post
 

Alright, while everyone's now officially jumped onto the ECC88 bandwagon, I'm still investigating the -just as expensive- ECC83 family (12AX7).

 

The thing is that the Telefunken 12AX7 tubes aren't rare, but there are like no NOS ones anymore, so people just keep exchanging the same old tubes, and those are just getting weaker and weaker every year.

The new Black Diamond Series will be out soon for the rolling...

 

post #3559 of 7220
Quote:
Originally Posted by TrollDragon View Post
 

The new Black Diamond Series will be out soon for the rolling...

 

Huh, fascinating! Marketing ploy or true high end new production? Who knows...

 

What is interesting is that it looks like the frame grid version of the 12AX7/ECC83; it looks like the ECC801S basically (which can cost a 4 digit figure for a pair btw).

post #3560 of 7220
Quote:
Originally Posted by gibosi View Post
 

 

This looks great, but we would really like to see the inside of your adapter.

 

Sorry but i did not take any photos from inside. I think that the most important thing is how are everything connected.

 

Left channel B7G to B9A

5 - 1

1 - 2

2 - 3

3 - 4 via switch

4 - 5 via switch

 

Right channel B7G to B9A

5 - 6

1 - 7

2 - 8

 

B9A pin 9 is connected to switch. Via switch you can take grounding for 6.3v tubes from little dot chassis. And here is a kind of diagram to show how the switch should be connected and how you solder wires to triple ON OFF ON switch. Sorry for non-steady hand and bad drawings.

1000

I tested also that if switch is in wrong position, heater just won't work and nothing got broken.

 

Btw, i really like sound of JJ electronic ECC83 S tube, that little what i have had time to listen.


Edited by Artsi - 10/17/13 at 1:59pm
post #3561 of 7220

Here is a link to these 12AT7 Telefunken branded tubes. It looks to me that these are mainly rebranded GE , National and Phillips tubes. Prices range from $20 to $99 each. They are NOT the real thing but carefully rebranded with the latest Swiss technology to look like Telefunken tubes.

 

"Impress your friends"

 

http://www.telefunken-elektroakustik.com/products/tubes/

post #3562 of 7220

I can see the same thing on my couple of Yugoslavian 6HM5 : a flash on one tube for only 1 seconds.

 

Are very nice and cheap tubes, but today is arrived a couple of Eico GE 6AV6 year 1958, and i'm in love.

http://www.ebay.it/itm/Eico-GE-6AV6-matched-pair-tubes-Very-Rare-12AX7-half-section-GE-Sonics-1958-/281189717133?pt=Vintage_Electronics_R2&hash=item417836948d

 

 

I think is the same tube 1958 GE owned by Gibosi.

 

For my ears, this is the "best ever...", all is perfect, soundstage and vocalist positions 3D, sound transparent and detailed, cristal highs and extended, but is an impression of an half hour,

 

Eico aren't cheap tubes, but if you want to try a couple, soon you will forget the price cost, but not quality sound:wink_face:

 

 

 

 

Quote:

Originally Posted by mordy View Post
 

My Yugoslavian Ei 6HM5 tubes finally arrived after 17 days. They are easy to use; just set the amp for EF95 and plug them in.

First impression is that they sound good with strong bass and that the tubes are very musical. Full review has to wait until they are burnt in.

 

What is most impressive however, is the fireworks display every time I turn on the amp. There is a huge flash that could scare you if you did not expect it, and then the glow dies down to a normal level.

 


This flash-up happens in a second or so. Set my camera for burst mode to take six pictures at a time. I am apologizing for the blurry pictures but you get the idea.

 

The other thing is that the build quality seems to be less precise than other European tubes but the sound does not seem to suffer.

 

Interesting tube.....

post #3563 of 7220
Quote:
Originally Posted by Iron58p View Post
Are very nice and cheap tubes, but today is arrived a couple of Eico GE 6AV6 year 1958, and i'm in love.
http://www.ebay.it/itm/Eico-GE-6AV6-matched-pair-tubes-Very-Rare-12AX7-half-section-GE-Sonics-1958-/281189717133?pt=Vintage_Electronics_R2&hash=item417836948d
 
 I think is the same tube 1958 GE owned by Gibosi.
 
For my ears, this is the "best ever...", all is perfect, soundstage and vocalist positions 3D, sound transparent and detailed, cristal highs and extended, but is an impression of an half hour,
 
Eico aren't cheap tubes, but if you want to try a couple, soon you will forget the price cost, but not quality sound:wink_face:

 

Yes, I have these tubes, GE 6AV6 rebranded as EICO. And until I began to roll 6-volt double triodes, I considered these to be my NO 1 tube. :)

post #3564 of 7220
Quote:
Originally Posted by Artsi View Post
 

B9A pin 9 is connected to switch. Via switch you can take grounding for 6.3v tubes from little dot chassis. And here is a kind of diagram to show how the switch should be connected and how you solder wires to triple ON OFF ON switch. Sorry for non-steady hand and bad drawings.

 

 

Thank you for this! :)

 

And I am now very hopeful that once I can connect pin 9 to the LD chassis ground, I will finally be able to run both triodes in one tube. I currently have a few singles, a Valvo PCC88 with a D-getter (but no visible tube codes), a Siemens PCC88, 1960, and an RCA ECC88, made in Holland, 1974, with a much simpler getter support assembly than the older tubes.

post #3565 of 7220

Regarding the ECC 83 mod hopefully at one point we will have a detailed how to for the mod visually seeing where the wires go where the ground goes the type of switches used  the type of sockets used ects. and hopefully trying to understand the schematic and what it means .Not being very knowledgeable in electronics dont really understand much but a simplified version with pictures  would help. Of course this takes time so theres no rush just putting it out there it would help others as well i am shure Thanks.

post #3566 of 7220

I used switch that looks like this. ON-OFF-ON type was mine, dunno is there just ON-ON available.

700

B9A socket, i tried to find best duration for tube rolling, i think.

CREATOR: gd-jpeg v1.0 (using IJG JPEG v80), quality = 90

 

In ECC83 mod Pin 9 is used as heater center tap. http://en.wikipedia.org/wiki/12AX7. In ECC88 mod it could be grounded, but can't see any reasons for that. I do not hear any humming or additional noise, even by touching tubes. 

post #3567 of 7220

More nice Soviet tubes in the house...

A quad of Svetlana 6Ж5П's have arrived from a great eBay seller in Bulgaria,

and it was nice to find all the pins were nicely cleaned before they arrived.

 

With the box as a backdrop...

 

 

Then you plug it in and the Magic Happens! (Click to show)

 

Since these tubes can only be run with a 2-7 strap, I took them down to the shop to solder some 30AWG wire wrap wire between pins 2 & 7. With the wire all stripped with a singe wrap around the pin 7, I applied the heat. What resulted was a nice sharp cracking sound, a large rift appeared in the glass and this tube was useless.

I heated another pin just for for schiit's & giggles, the same thing happened, a nice big crack appeared in the glass.

Thankfully I picked up 4 of them and I'm glad that this never happened with my USAF 6AH6WA's.

 

If you pick these tubes up, DO NOT TRY TO SOLDER THE PINS, I didn't attempt a second tube, it wasn't worth the risk.

I'll just put my switches in EF95 2-7 mode and away we go.

:beerchug: 


Edited by TrollDragon - 10/17/13 at 9:46pm
post #3568 of 7220

If i thought tube rolling is getting bored, then here is little list of tubes and variants, that should work now with my little dot. List is with heater currents and amplification factors.

 

6V tube types
 
ECC88 6DJ8 6N23P CV5358 M3624        0.35A 33x
E88CC 6922 CCa CV2492 CV2493 9622  0.30A 33x
E188CC 7308 CV4108                         0.35A 33x
E288CC 8223                                    0.47A 25X
ECC85 6AQ8 B719 6L12                      0.44A 57X
ECC86 6GM8 6N27P                           0.30A 14X
ECC189 6ES8                                   0.36A 31X
ECC804 6GA8 6/30L2                         0.30A 18X
ECC812                                          0.44A 50X
ECC865                                          0.44A 58X
ECC180 6BZ7 6BQ7 6BS8 6T27           0.40A 36X
6N2P 6CC41                                    0.34A 100X
6BK7                                              0.45A 40X
6BC8 6BZ8                                      0.40A 35X
PCC88 7DJ8                                     0.30A 33X
 
12V tube types
 
ECC83 12AX7 B339 95-127-01 6L13 CM1        0.30A 100X
ECC82 12AU7 B329 95-126-01 CC82E CV491  0.30A 17X
ECC81 12AT7 B152 CC81E CV455                 0.30A 60X
E81CC 12AT7WA CV6091 6201                     0.30A 60X
E82CC 6189 M8136 6189W                         0.30A 17X
E83CC 12AX7WA 6057                              0.30A 100X
E180CC CV8431 7062                               0.40A 50X
E181CC                                                  0.40A 32X
ECC186 12AU7WA 7316                              0.30A 17X
ECC802S                                                 0.30A 17X
5751 GL5751 CK5751 CV4017                      0.35A 70X
5814A CK5814-A                                      0.35A 17X
5963 CV3900                                           0.30A 21X
5965 6829                                               0.45A 47X
6679                                                      0.30A 60x
7025                                                      0.30A 100X
12AD7                                                   0.45A 100X
12DF7                                                   0.30A 100X
6680                                                     0.30A 20X
6211                                                     0.30A 27X
12AZ7                                                   0.45A 60X
12AD7                                                   0.45A 100X
12AV7                                                   0.45A 40X
12AY7 6N4P                                           0.30A 40X
12DM7                                                   0.26A 100X
12DF7                                                   0.30A 100X
12DT7                                                   0.30A 100X
12U7                                                     0.30A 20X

Edited by Artsi - 10/18/13 at 8:39am
post #3569 of 7220
Quote:
Originally Posted by Artsi View Post
 

If i thought tube rolling is getting bored, then here is little list of tubes and variants, that should work now with my little dot. List is with heater currents and amplification factors.

 

6V tube types
 
ECC88 6DJ8 6N23P CV5358 M3624        0.35A 33x
E88CC 6922 CCa CV2492 CV2493 9622  0.30A 33x
E188CC 7308 CV4108                         0.35A 33x
E288CC 8223                                    0.47A 25X
ECC85 6AQ8 B719 6L12                      0.44A 57X
ECC86 6GM8 6N27P                           0.30A 14X
ECC189 6ES8                                   0.36A 31X
ECC804 6GA8 6/30L2                         0.30A 18X
ECC812                                          0.44A 50X
ECC865                                          0.44A 58X
ECC180 6BZ7 6BQ7 6BS8 6T27           0.40A 36X
6N2P 6CC41                                    0.34A 100X
6BK7                                              0.45A 40X
6BC8 6BZ8                                      0.40A 35X
 
12V tube types
 
ECC83 12AX7 B339 95-127-01 6L13 CM1        0.30A 100X
ECC82 12AU7 B329 95-126-01 CC82E CV491  0.30A 17X
ECC81 12AT7 B152 CC81E CV455                 0.30A 60X
E81CC 12AT7WA CV6091 6201                     0.30A 60X
E82CC 6189 M8136 6189W                         0.30A 17X
E83CC 12AX7WA 6057                              0.30A 100X
E180CC CV8431 7062                               0.40A 50X
E181CC                                                  0.40A 32X
ECC186 12AU7WA 7316                              0.30A 17X
ECC802S                                                 0.30A 17X
5751 GL5751 CK5751 CV4017                      0.35A 70X
5814A CK5814-A                                      0.35A 17X
5963 CV3900                                           0.30A 21X
5965 6829                                               0.45A 47X
6679                                                      0.30A 60x
7025                                                      0.30A 100X
12AD7                                                   0.45A 100X
12DF7                                                   0.30A 100X
6680                                                     0.30A 20X
6211                                                     0.30A 27X

 

And you can add PCC88 / 7DJ8. :)

post #3570 of 7220
Quote:
Originally Posted by gibosi View Post
 

 

And you can add PCC88 / 7DJ8. :)

Heating is little slower, but it should work.

 

I added some paint to my "little box". It does not look so much prototype anymore.

700

Double triodes do something positive things to music. I listened to Lindsey Stirling and Melody Gardot and nearly cried how good it sounds. Music comes more from outside your head and i easily forget that i wear headphones. Recording studio echos from walls etc seems to be more easily audible.

New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › Little Dot Tube Amps: Vacuum Tube Rolling Guide