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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 434

post #6496 of 10574
Quote:
Originally Posted by manizkrishnan View Post
 

Hello, I recently bought Russian Tubes 6Zh1P-EV = 6J1P-EV ( 6Ж1П-ЕВ ) an quality equivalent of the EF95 / 6F32 and NOS RUSSIAN TUBES 6N6P-I ( 6Н6П-И ) an quality equivalent of the ECC99 / E182CC for my liitle dot MK III amp. Can i install these tubes with out changing anything? You seems to know lot about tube rolling. any help would be really appreciated.

I just went through the whole tube rolling thing. 6zh1p are better than stock driver tubes and 6n6P-I are really good my favorite of all. I recently got a pair of 6HM5 (tall )from EB suggested by few guru on this thread and indeed they are my favorite combo. 6N6P-I & 6HM5 (got them for 5 USD ea.). Then there are other options.... 6SN7 as power tube.

post #6497 of 10574

Thanks for the reply. I have not received my tubes yet. I will try these tubes for a while. So i can just replace the stock tubes with these tubes right? No need to change anything inside the amp?

post #6498 of 10574
Quote:
Originally Posted by manizkrishnan View Post
 

Hello, I recently bought Russian Tubes 6Zh1P-EV = 6J1P-EV ( 6Ж1П-ЕВ ) an quality equivalent of the EF95 / 6F32 and NOS RUSSIAN TUBES 6N6P-I ( 6Н6П-И ) an quality equivalent of the ECC99 / E182CC for my liitle dot MK III amp. Can i install these tubes with out changing anything? You seems to know lot about tube rolling. any help would be really appreciated.

 

Yes, you can use the 6J1P-EV and the 6N6P-I in your Little Dot without changing anything.

post #6499 of 10574

I'm sure many of you know the feeling. You turn on your beloved system, and somethin' is wrong. What, the left channel isn't working! What could the problem be? Speakers? PC? Bad connection? Did you finally kill the LD?

 

Well, u didn't listen to TD, and you did this crazy stuff and ran one channel on 12V and the other on 6V, and you used a 2.5A tube (with ext PS) where the max is 1.25A. How much does it cost to send it back to China? How do you contact LD? How long will it take to get it fixed? Could it be one of those pesky resistors (shudder)?Is it cheaper to buy a new one? MKIII or IV?

 

Perspiration, anxiety, worry. How can I listen to mediocre sound in the absence of the LD?

 

Well, let's see. Pull out all the external stuff, pull on all the wires, change all the tubes to OEM stuff. PC? - no, it works both channels. LD? Only the right channel. OK, I'll rewire the 6832 adapter; while I'm at it I'll add some some heat shrink insulation; seems less messy than turquoise nail polish - or red nail nail polish. Slap everything together. Perspiration. Doing a mental check: Can't remember any electronic acrid burnt smell, no poof or loud crackle. All three heaters light up. OK - turn on the sound. Sounds good, BUT ONLY THE RIGHT CHANNEL. Panic.

 

Well, it got to be something simple. Maybe. Didn't smell anything acrid, right. Of course, it must be that one of the E95 jumpers underneath worked itself loose or corroded. You just had to demonstrate that drum solo to one of your grand children, didn't you? Check - nyet; everything in place. Still NO LEFT CHANNEL. What's next? Check all the cables to the LD - everything OK. Calm down, take a few deep breaths, think about something else (can't). RELAX, RELAX.

 

To make a long story short: On the back of my 35 year old Sony amp is a slider switch that switches on and off an external equalizer loop. The LD is connected to this loop. Turns out that the switch corroded and killed the left channel. A few pushes back and forth cleared up everything. Hurray! Everything works! Need to get the super advanced hi tech super mods in place again - 12.6V 12SN7GT, 6.3V 6080, and the 6832 in it's new red clothes.

 

Relief...RELIEF....RELIEF

 

Another day in the life of a Little Dot owner.....


Edited by mordy - 6/9/14 at 9:42pm
post #6500 of 10574

Thank You :) I am so excited now.

post #6501 of 10574
Good to hear mordy it was only the tape monitor switch on the receiver.

You would definitely know the smell of cooked resistors, they have a unique smell that lingers. When electrolytic capacitors go, its usually with a bang sometimes as the metal can flys off. Other times its just a loud hiss and a nasty smell of cooked electrolyte.

Time to pick up a little contact cleaner for the switches on the receiver.
beerchug.gif
post #6502 of 10574
For anyone interested in the C3G tubes, I'm selling my two with 6ak5 adapters. Pm for a way to save some scratch on importing and wait times.
post #6503 of 10574

So I've now got 3 sets of drivers:

 

Mullard M8100 with 10 hours of burn-in

Voskhod 6ZH1P-EV with 4 hours of burn in

Stock Tubes with 20 hours of burn in

 

At the moment, Voskhod >> Stock > Mullard. So, I know I'm nowhere near fully burnt-in on any of the tubes, but I'm surprised that the stock ones are still (a little) better than the Mullards at this point in time - and that the Voskhods are so good with so little burn-in time. Can I expect the Mullards to catch up after some more hours burn-in? Or will they start to shine with the 6H30Pi power tubes? (which have *just* arrived BTW - I was expecting a few more day's playtime with the drivers first - I bet if I'd been desperate for them they would have taken weeks).

post #6504 of 10574
Quote:
Originally Posted by tjw321 View Post
 

So I've now got 3 sets of drivers:

 

Mullard M8100 with 10 hours of burn-in

Voskhod 6ZH1P-EV with 4 hours of burn in

Stock Tubes with 20 hours of burn in

 

At the moment, Voskhod >> Stock > Mullard. So, I know I'm nowhere near fully burnt-in on any of the tubes, but I'm surprised that the stock ones are still (a little) better than the Mullards at this point in time - and that the Voskhods are so good with so little burn-in time. Can I expect the Mullards to catch up after some more hours burn-in? Or will they start to shine with the 6H30Pi power tubes? (which have *just* arrived BTW - I was expecting a few more day's playtime with the drivers first - I bet if I'd been desperate for them they would have taken weeks).

 

What is "great" for one person is often just "so-so" for another, even given the same amp, tubes and headphones. And so it is hard to predict which tubes will be "your" favorites. For now, it is best to withhold judgement until all of them have been burned in, and then you can do a shootout to figure out which is best given your ears and gear.

post #6505 of 10574
Quote:
Originally Posted by gibosi View Post
 

 

What is "great" for one person is often just "so-so" for another, even given the same amp, tubes and headphones. And so it is hard to predict which tubes will be "your" favorites. For now, it is best to withhold judgement until all of them have been burned in, and then you can do a shootout to figure out which is best given your ears and gear.

Thanks - will do. The shootout is (at least) half the fun, after all :beerchug: 

post #6506 of 10574

Another update on the use of subminiature dual triode vacuum tubes with eight thin flexible leads in the LD amps. IMHO this approach of solderless connections should make it easy for anyone to try these type of tubes.

 

All you need is 1mm heat shrink tubing and 18 gauge solid copper wire + one 9 pin tube socket saver/extender and a breadboard.. A cigarette lighter can be used as a heat source for shrinking the tubing. (It would be possible to make the leads a little longer and do away with both the breadboard and socket extender and just stick in the appropriate leads directly into both driver tube sockets.)

 

Cut the tubing to cover the flexible leads, cut up little pieces of 1" copper wire. Insert the copper pieces into the heat shrink tube, leaving 5mm exposed wire sticking out. Heat and serve.

 

Here the 6832 does it's octopus imitation:

 

Look, new shoes! (I did scrape off the little oxidation from the flame)

 

 

Close-up of wiring into socket extender. A little tricky to get the right order, but not too difficult.

 

 

Action photo. It is not necessary that the flexible wires are absolutely straight as long as you can thread the sleeve on. The heat shrinking makes for a tight good fit. If you want to change tubes, just pull out the socket extender the same as any other tube.

 

These little submini tubes are not visually appealing, but sound wise they can stand their own against anything we've tried, including the priciest icons. If you haven't heard one yet, give it a try. You may be in for a surprise.....

post #6507 of 10574

Hi tjw321,

 

Based on experience most tubes need 30-50 hours of burn in to stabilize. The Voskhods are an exception - they need 110-120 hours of burn in. And the 6832 submini came into it's own after some 70 hours...

 

Patience, patience


Edited by mordy - 6/10/14 at 11:49am
post #6508 of 10574
Quote:
Originally Posted by mordy View Post
 

Hi tjw321,

 

Based on experience most tubes need 30-50 hours of burn in to stabilize. The Voskhods are an exception - they need 110-120 hours of burn in.

Thanks - I had a feeling that I'd read that the Voskhods were supposed to take a bit longer - that's why I was a bit surprised that they were appreciably better than the Mullards after a much shorter burn in time. Maybe the Mullards need a bit more contact cleaning. I have too much burning in to do....so many tubes, so little time :D

post #6509 of 10574
Quote:
Originally Posted by CITIZENLIN View Post
 

Looks like I am onto a long ride of back and fort emails with "happydiy998".

I just received two emails with different tunes

The first one said

 

========

Hello,

We will ship one pair tomorrow again,

please kindly ship back the two pcs you received to following address:

Ms. Tse Yuk Chi, Shop 20, G/Fl., Fullview Garden Shopping Centre, 18 Siu Sai Wan Road, Hong Kong. 00852 92166680

tomorrow or the day after tomorrow, we will send you tracking number,

any questions, please kindly contact us again,

Thanks&Best Regards,
Vanessa

 

- happydiy998
====
 
Then I asked her to make sure they work before she them out replacement. This is her 2nd email within 2 hours from previous email
 
=======
 
Hello,

This adapter is made by hand, so every item can not look exactly the same, and meterial can not be find easily, I will ask our technical person becareful when he makes the adaters,

We sold several pairs, now only you says they are not work, we want to test the adapters, would you please ship it back for a check? we did tested it before delivery,

my suggestion is to refund you money fully, and you send back the adapters to us to check, when we confirm the adapters are defective, we will send another pair for free, if not, we will send you money for the shipping cost you spend, is that ok?

Looking forward to hearing from you soon,

Thanks&Best Regards,
Vanessa
=======
 
Simple plug and play turning into nightmare. I don't like the direction its going . SIGH.....
 

 

Hi C.

 

Am SO disheartened you are going through the mill for something that should - and eventually WILL, mon ami - be bringing wonderful anticipation, then overwhelming joy, lol!

 

It's almost as if I talked it up when I mentioned some time ago that I hoped the adapter-makers did nothing to spoil the magic of these tubes...deja vu?!

 

I must admit I am not at all impressed with the examples you have shown...you MUST demand better - I am a real amateur, but even the ones I made (the first being a little 'Heath Robinson', admittedly!) didn't look too bad and WORKED!!...well actually, they were even more tricky because I attached the new (silver) pins direct to the tube pins...baptism of fire, you might say!

 

So COURAGE, my friend...  you will get there in the end, and it will all be worthwhile...:p.

 

 

Quote:
Originally Posted by mordy View Post
 

I'm sure many of you know the feeling. You turn on your beloved system, and somethin' is wrong. What, the left channel isn't working! What could the problem be? Speakers? PC? Bad connection? Did you finally kill the LD?

 

Well, u didn't listen to TD, and you did this crazy stuff and ran one channel on 12V and the other on 6V, and you used a 2.5A tube (with ext PS) where the max is 1.25A. How much does it cost to send it back to China? How do you contact LD? How long will it take to get it fixed? Could it be one of those pesky resistors (shudder)?Is it cheaper to buy a new one? MKIII or IV?

 

Perspiration, anxiety, worry. How can I listen to mediocre sound in the absence of the LD?

 

Well, let's see. Pull out all the external stuff, pull on all the wires, change all the tubes to OEM stuff. PC? - no, it works both channels. LD? Only the right channel. OK, I'll rewire the 6832 adapter; while I'm at it I'll add some some heat shrink insulation; seems less messy than turquoise nail polish - or red nail nail polish. Slap everything together. Perspiration. Doing a mental check: Can't remember any electronic acrid burnt smell, no poof or loud crackle. All three heaters light up. OK - turn on the sound. Sounds good, BUT ONLY THE RIGHT CHANNEL. Panic.

 

Well, it got to be something simple. Maybe. Didn't smell anything acrid, right. Of course, it must be that one of the E95 jumpers underneath worked itself loose or corroded. You just had to demonstrate that drum solo to one of your grand children, didn't you? Check - nyet; everything in place. Still NO LEFT CHANNEL. What's next? Check all the cables to the LD - everything OK. Calm down, take a few deep breaths, think about something else (can't). RELAX, RELAX.

 

To make a long story short: On the back of my 35 year old Sony amp is a slider switch that switches on and off an external equalizer loop. The LD is connected to this loop. Turns out that the switch corroded and killed the left channel. A few pushes back and forth cleared up everything. Hurray! Everything works! Need to get the super advanced hi tech super mods in place again - 12.6V 12SN7GT, 6.3V 6080, and the 6832 in it's new red clothes.

 

Relief...RELIEF....RELIEF

 

Another day in the life of a Little Dot owner.....

 

Hey mordy...PLEASE, PLEASE don't deliver such shocks...my poor old ticker can't handle it!

 

Had nightmare visions of the (MY!!) amp suddenly doubling as a toaster, given the punishment we are now meting out to the poor old thing(s)...

 

But SO glad it turned out to be just a minor hiccough...and that you did actually manage to find its source...a touch of Sherlock Holmes, or just plain GOOD LUCK?!

 

Cheers...

 

ps. Don't do it again...please! :eek:...and  :D

post #6510 of 10574
Quote:
Originally Posted by CITIZENLIN View Post
 

Looks like I am onto a long ride of back and fort emails with "happydiy998".

I just received two emails with different tunes

The first one said

 

========

Hello,

We will ship one pair tomorrow again,

please kindly ship back the two pcs you received to following address:

Ms. Tse Yuk Chi, Shop 20, G/Fl., Fullview Garden Shopping Centre, 18 Siu Sai Wan Road, Hong Kong. 00852 92166680

tomorrow or the day after tomorrow, we will send you tracking number,

any questions, please kindly contact us again,

Thanks&Best Regards,
Vanessa

 

- happydiy998
====
 
Then I asked her to make sure they work before she them out replacement. This is her 2nd email within 2 hours from previous email
 
=======
 
Hello,

This adapter is made by hand, so every item can not look exactly the same, and meterial can not be find easily, I will ask our technical person becareful when he makes the adaters,

We sold several pairs, now only you says they are not work, we want to test the adapters, would you please ship it back for a check? we did tested it before delivery,

my suggestion is to refund you money fully, and you send back the adapters to us to check, when we confirm the adapters are defective, we will send another pair for free, if not, we will send you money for the shipping cost you spend, is that ok?

Looking forward to hearing from you soon,

Thanks&Best Regards,
Vanessa
=======
 
Simple plug and play turning into nightmare. I don't like the direction its going . SIGH.....
 

I heard that tune before good luck!

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