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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 436

post #6526 of 10509
Quote:
Originally Posted by TrollDragon View Post

So I have this shaft with a sealed bearing in a pillow block, there is too much torque on the bearing, it gets hot and starts to squeal. I put a fan or two in front of the pillow block to blow away the heat, now the bearing is quiet...

Does this not seem like a problem?

The properly designed bearing would have a grease nipple on it to apply some of Titans oil as it is designed to take the load.

Which reminds me of an old gir...
Never Mind. tongue.gif

No need to worry if i ever use a fan i will use one of this.:biggrin:

images?q=tbn:ANd9GcRQGVifnWxfQjo9cnV6S6AwNQoCrAMscmjKZnlww0DZfwTtjw5VKg

JUST KIDDING TD!:tongue_smile:

post #6527 of 10509
That will work providing you can drive enough kerosene into it at a decent rate...
biggrin.gif
post #6528 of 10509

Maybe this machine will take care of the cooling of 3 6080s........

 

http://www.wired.com/images_blogs/autopia/2012/02/Facility-2-4x5.jpg

 

All kidding aside, my amp is cool to the touch with the A/C on and a room temperature of 72F with the 4" fan on. Have to see how it works with two 6080s.

 

Yesterday ran the amp 9 hours without problems.

 

PS: If you are curious what this is, it's a wind tunnel to test jet engines in cold weather ingesting ice and rain.

      http://www.wired.com/2012/02/ge-heads-north-for-new-jet-engine-ice-test-facility/


Edited by mordy - 6/11/14 at 5:34pm
post #6529 of 10509
Quote:
Originally Posted by CITIZENLIN View Post
 

I think they are the same but the tube on mine are unevenly sticking out.

 

Still looking for hidden ON/OFF switch on adapter. LOL :):o2smile:

 

 

 


Hi, i found the seller to be very friendly but we also had one tube with a slightly cracked base holding the pins but which still worked.I hope you get to enjoy your C3G's very soon.I have experienced them to be very resolving with good presentation of freq. spectrum.

post #6530 of 10509
Quote:
Originally Posted by TrollDragon View Post


The Coax Out from the X3 should be very nice into the Arcam for sure, I would have rather had an Optical on the X3, not for any specific sound difference from Coax, I just like Toslink cables... smily_headphones1.gif

Enjoy the 6HM5's when they arrive.
beerchug.gif

The 6HM5s just arrived. I haven't had much time with them yet, but judging by the first session, these are going to be my "keepers". And they were the cheapest - if they live up to their initial promise I might get a couple of spares whilst I can.

 

Thanks for the tip.

post #6531 of 10509
Quote:
Originally Posted by sgbwill2 View Post
 

Hi guys. Seen as the 7 pin extenders/socket savers were lost in transit I decided to remove the brass rings. After much deliberation I got them off and now the 6sn7's and c3g's fit and no extenders are needed. Now I'm just wondering how people have removed the metal casings on the c3g's? Thought I would ask in advance just in case I break the tubes removing them.

 

Thanks

 

Hi sgb.

 

Was intrigued as to how you removed those rings...I'm sure your fellow MKIII owners would be grateful for any advice, if interested in the latest 'super' mods!

 

Quote:
Originally Posted by tjw321 View Post
 

The 6HM5s just arrived. I haven't had much time with them yet, but judging by the first session, these are going to be my "keepers". And they were the cheapest - if they live up to their initial promise I might get a couple of spares whilst I can.

 

Thanks for the tip.

 

Good to hear you like the 6HM5s...certainly about the best straight replacement for the (much inferior) stock.

 

It seems a lifetime ago now since gibosi first gave these a try, but despite fear of repetition I must urge you to continue the quest...as you must have gathered by now, we have found MUCH better still. If funds permit, the C3G driver is WAY ahead, and improves yet again with 6SN7s as power tubes (the 6AS7G/6080 may be just a step too far for you?!). And there are adapters available for both said driver and power...and if sgbwill2 has found a (not too difficult)  way to remove those rings, you may not have to worry about the additional 'extenders'.

 

Just food for thought, lol?

post #6532 of 10509
Quote:
Originally Posted by hypnos1 View Post
 

 

Hi sgb.

 

Was intrigued as to how you removed those rings...I'm sure your fellow MKIII owners would be grateful for any advice, if interested in the latest 'super' mods!

 

 

Good to hear you like the 6HM5s...certainly about the best straight replacement for the (much inferior) stock.

 

It seems a lifetime ago now since gibosi first gave these a try, but despite fear of repetition I must urge you to continue the quest...as you must have gathered by now, we have found MUCH better still. If funds permit, the C3G driver is WAY ahead, and improves yet again with 6SN7s as power tubes (the 6AS7G/6080 may be just a step too far for you?!). And there are adapters available for both said driver and power...and if sgbwill2 has found a (not too difficult)  way to remove those rings, you may not have to worry about the additional 'extenders'.

 

Just food for thought, lol?

Thanks for the words of encouragement - much appreciated. I've only had the Little Dot for about 2 weeks and I have 4 sets of drivers and 2 sets of power tubes. I don't think there is really much chance I'm going to stop there. ;)

I should get at least one set properly burnt-in, though. I'm particularly keen to give the Mullards some more time as, based on others' impressions of them, they should suit me to a tee. So my short term goal is to give the Mullards more chance to shine, and to see how the 6HM5s go.

Longer term - who knows? :D  It'll be a few months before I'm tempted by any "major surgery" though... 

post #6533 of 10509
Quote:
Originally Posted by hypnos1 View Post
 

 

Hi sgb.

 

Was intrigued as to how you removed those rings...I'm sure your fellow MKIII owners would be grateful for any advice, if interested in the latest 'super' mods!

 

 

Hi hypnos,

 

It wasnt all too difficult really. All I did was I undid the screws at the back of the amplifier so the panel can partially come off (as wires still keep it attached) then I undid the alan key screws at the front and then took off the volume knob (using an alan key again as theres a small hole on the knob which has an allan key screw in it) after this you can completely remove the front cover (after detaching the volume control from the front cover by un-bolting it). After this I undid the screws on the top of the amplifier which fixes the board of the little dot in place. After this you can slide the whole board backwards as the front panel no longer obstructs the movement as only the volume control device is attached which is small enough to fit through the amplifier chassis. The wires quite often got tangled on some of the other components within the amplifier when sliding the board back so I would take care and don't yank it (I suggest using a screw driver to manipulate the wires around the components so you can slide it back far enough). Once the board is slid far enough back you can access the screws which hold the brass rings in place (2 per brass ring) easily as the 8 small circular holes on the base of the amplifier are all located directly above the screws (I always thought they were part of some sort of ventilation though it is clear they were drilled as access to attaching the screws for the brass rings). After the brass rings are removed just put it back together again :) (though make sure when you put the volume knob back on that you have the volume device turned all the way to the left and that it is pointing to the 0 volume mark). After this no extenders are needed for either the front or back tubes and looks much better than having the extenders (+ saves some money).

 

Hope this helps. Sorry for no photos but I don't fancy taking it all apart again :D

 

Btw thanks for your guide on removing the metal covers on the c3g's hypnos I decided not to use any glue and they work fine once in the adapters. (shame though that there isnt much tube glow from these c3g's)


Edited by sgbwill2 - 6/12/14 at 2:07pm
post #6534 of 10509
Quote:
Originally Posted by philiptw View Post
 

 

Hey there,

 

I took the exact same steps of gear acquisition as you :-)

 

As my signature states, my source is the DX90.

 

The Mullards will indeed become better and better as they burn in further.

Personally I found the Voskhods to not be as fully "bodied" as the Mullards, and the detail can be just a tad too much for my personal taste at times (can become fatiguing IMO).

The Mullards have been sitting in my Driver slots the most since their arrival and I think that suggests something.

 

I rolled 6H30Pi-EHs for my power tube and I think there is not a dramatic difference in sound when compared to the stock tubes.. but I am using the 6h30pi for now and keeping the stock power tubes as backups.

 

Enjoy the journey of tube rolling.. before the upgraditis bug hits again.. which has already done so for me... haha!

I've been getting a bit frustrated with my Mullards because I couldn't get a decent sound out of them. They're still burning in, so that could be some of it, but I just tried them for the first time with the 6H30Pi power tubes......Wow - now I understand :D. Maybe it's just a coincidence and they just burnt in enough just before I swapped the power tubes, but I don't care - Right now I'm enjoying Eddi Reader more than I ever have before! Of course, tomorrow I'm going to have to try her with the 6HM5s...

There really is no end to this journey once you've started, is there? Well, except for full-blown upgraditis. :) 


Edited by tjw321 - 6/12/14 at 2:17pm
post #6535 of 10509
Nice very nice!

The journey down the rabbit hole has only just begun. biggrin.gif

What gain are you running the amplifier at? They come default at 3, it wasn't until I switched mine to 5 before it started to really open up. The 10 setting got too loud too fast, so I switched mine back to 5 and that's where it has been ever since.

Something else you might want to play with because it does change the sound. I like my volume control between 10 and 11 o'clock for a really nice listening level and that's with 5 gives me.

beerchug.gif
post #6536 of 10509
Quote:
Originally Posted by TrollDragon View Post

Nice very nice!

The journey down the rabbit hole has only just begun. biggrin.gif

What gain are you running the amplifier at? They come default at 3, it wasn't until I switched mine to 5 before it started to really open up. The 10 setting got too loud too fast, so I switched mine back to 5 and that's where it has been ever since.

Something else you might want to play with because it does change the sound. I like my volume control between 10 and 11 o'clock for a really nice listening level and that's with 5 gives me.

beerchug.gif

I haven't tried changing the gain yet. I'm at about 10 O'Clock with my HD 600s which seemed reasonable and with four sets of drivers and two sets of power tubes I had enough variables to play with. I don't think I'll ever go back to the stock power tubes (not because they were terrible, but I don't feel any need to do that experiment any more), and I'm down to a choice between the Mullards and 6HM5s for pole position in the driver's seat - with the Voskhods taking the wheel for the occasional special circumstance (basically, if I fancy a bit of a change...). Now I think could be a good time to explore the gain switches.

 

It's kind of funny that the plan was to play with the switches first, and then try the tubes as and when they arrived....but they all arrived within a day or two of ordering except for the ones which I paid for delivery, and came from just a few miles away. Next day delivery from Serbia to the UK was free!

 

Thanks for the help, assistance and advice. :beerchug:

 

A quick question for the experts - I read somewhere that part of the tube burn-in process was getting them hot enough to activate the scavenging coating on the inside of the tube to collect up the last few molecules of non-vacuum. The last time I used the Mullards I ran them for about 8 hours so they were good and hot, but they sounded pretty rough. The next time I use them, they sound smoother than a very smooth thing. Could the burn in have continued after I stopped listening, or does there actually have to be an audio signal going through them.?

post #6537 of 10509
Quote:
Originally Posted by mordy View Post
 

Maybe this machine will take care of the cooling of 3 6080s........

 

http://www.wired.com/images_blogs/autopia/2012/02/Facility-2-4x5.jpg

 

All kidding aside, my amp is cool to the touch with the A/C on and a room temperature of 72F with the 4" fan on. Have to see how it works with two 6080s.

 

Yesterday ran the amp 9 hours without problems.

 

PS: If you are curious what this is, it's a wind tunnel to test jet engines in cold weather ingesting ice and rain.

      http://www.wired.com/2012/02/ge-heads-north-for-new-jet-engine-ice-test-facility/

That's not gonna work it only have 7 tiny fans......:atsmile:

post #6538 of 10509
Quote:
Originally Posted by tjw321 View Post

I haven't tried changing the gain yet. I'm at about 10 O'Clock with my HD 600s which seemed reasonable and with four sets of drivers and two sets of power tubes I had enough variables to play with. I don't think I'll ever go back to the stock power tubes (not because they were terrible, but I don't feel any need to do that experiment any more), and I'm down to a choice between the Mullards and 6HM5s for pole position in the driver's seat - with the Voskhods taking the wheel for the occasional special circumstance (basically, if I fancy a bit of a change...). Now I think could be a good time to explore the gain switches.

It's kind of funny that the plan was to play with the switches first, and then try the tubes as and when they arrived....but they all arrived within a day or two of ordering except for the ones which I paid for delivery, and came from just a few miles away. Next day delivery from Serbia to the UK was free!

Thanks for the help, assistance and advice. beerchug.gif

A quick question for the experts - I read somewhere that part of the tube burn-in process was getting them hot enough to activate the scavenging coating on the inside of the tube to collect up the last few molecules of non-vacuum. The last time I used the Mullards I ran them for about 8 hours so they were good and hot, but they sounded pretty rough. The next time I use them, they sound smoother than a very smooth thing. Could the burn in have continued after I stopped listening, or does there actually have to be an audio signal going through them.?
You are most welcome, LD's are great amps, explore every feature and get the sound that works for you.

The silver part of the tubes is the Getter Flash that is done at the factory with an induction heater during manufacturing. You couldn't get the tube hot enough with use and there none of the initial barrium left in the tube.

Getter Info
http://www.wikipedia.org/wiki/Getter

I don't "burn-in" tubes personally, I plug them in and enjoy right from the start, others here have an idea as to how long different tubes take to reach optimal sound.

I personally don't believe in Headphone, Cable or especially Electronic device burn-in ie DAC's, SS Amps etc...

So others might chime in here with some times for you or just do as I do, leave the tubes in and enjoy the music. biggrin.gif
post #6539 of 10509
Quote:
Originally Posted by TrollDragon View Post


You are most welcome, LD's are great amps, explore every feature and get the sound that works for you.

The silver part of the tubes is the Getter Flash that is done at the factory with an induction heater during manufacturing. You couldn't get the tube hot enough with use and there none of the initial barrium left in the tube.

Getter Info
http://www.wikipedia.org/wiki/Getter

I don't "burn-in" tubes personally, I plug them in and enjoy right from the start, others here have an idea as to how long different tubes take to reach optimal sound.

I personally don't believe in Headphone, Cable or especially Electronic device burn-in ie DAC's, SS Amps etc...

So others might chime in here with some times for you or just do as I do, leave the tubes in and enjoy the music. biggrin.gif

One of my early posts on Head-Fi:

 

"I multi-task. I burn-in while listening to music...:wink_face:"

 

http://www.head-fi.org/t/651769/the-fiio-x3-thread/4995#post_9793341

 

This is the first time I've ever run pink noise through anything to burn it in. But with 2 pairs of head-phones, 4 sets of drivers, and 2 sets of power tubes and only a couple of hours a day to listen, I was in a hurry. :p

 

I have noticed that a far bigger effect than the burn in one comes from just getting the tubes seated properly. That might be where the huge improvement in the Mullards came from. I clean the contacts on my tubes with a contact cleaner when I get them, but a couple of re-insertions may well have helped improve contact - or I may just have not done a very good of seating them the first time. There are so many variables, it's just too easy to fool yourself.

 

Anyway, whatever the reason, I'm enjoying it too much. I had to get up at 5am this morning, so staying up late (1am) last night listening to music was probably not my best idea ever. I just..didn't...want...it...to...stop. :eek: 

post #6540 of 10509
Quote:
Originally Posted by sgbwill2 View Post
 

Hi hypnos,

 

It wasnt all too difficult really. All I did was I undid the screws at the back of the amplifier so the panel can partially come off (as wires still keep it attached) then I undid the alan key screws at the front and then took off the volume knob (using an alan key again as theres a small hole on the knob which has an allan key screw in it) after this you can completely remove the front cover (after detaching the volume control from the front cover by un-bolting it). After this I undid the screws on the top of the amplifier which fixes the board of the little dot in place. After this you can slide the whole board backwards as the front panel no longer obstructs the movement as only the volume control device is attached which is small enough to fit through the amplifier chassis. The wires quite often got tangled on some of the other components within the amplifier when sliding the board back so I would take care and don't yank it (I suggest using a screw driver to manipulate the wires around the components so you can slide it back far enough). Once the board is slid far enough back you can access the screws which hold the brass rings in place (2 per brass ring) easily as the 8 small circular holes on the base of the amplifier are all located directly above the screws (I always thought they were part of some sort of ventilation though it is clear they were drilled as access to attaching the screws for the brass rings). After the brass rings are removed just put it back together again :) (though make sure when you put the volume knob back on that you have the volume device turned all the way to the left and that it is pointing to the 0 volume mark). After this no extenders are needed for either the front or back tubes and looks much better than having the extenders (+ saves some money).

 

Hope this helps. Sorry for no photos but I don't fancy taking it all apart again :D

 

Btw thanks for your guide on removing the metal covers on the c3g's hypnos I decided not to use any glue and they work fine once in the adapters. (shame though that there isnt much tube glow from these c3g's)

 

All I can say is...WELL DONE! You did a fine job with those rings. A good deal of care is obviously needed when sliding back that board, but certainly doable.

Luckily I have the MKIV SE, so I don't have that particular problem - our tube rings and plate come off nice and easily from the top :regular_smile :. But I was hoping you could enlighten your fellow MKIII owners...which of course you have!!

 

Glad you managed to remove the C3Gs from their prison...sure looks much prettier, lol! - even if there isn't much glow :frown:. But if you want gorgeous glow, just take the 6AS7G high road...your mind would be blown in more ways than one - guaranteed! And your C3Gs would say a BIG "thank you"...

 

ps. Sorry if I'm stating the obvious (again), sgb, but please be extremely careful if you remove the tube and it separates from the base...as I mentioned before, the base can appear to fit on the tube in any position... just ensure the 'church windows' line up perfectly, and all is well.

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