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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 262

post #3916 of 5933
I don't think the pins nubs are causing your hum, if you had the tubes partially seated and they still hummed. It is probably just the tubes themselves.
post #3917 of 5933
Quote:
Originally Posted by TrollDragon View Post
 

 

Here's another one:

 

post #3918 of 5933

Just as a precaution, some tubes are more sensitive to RF noise than others. Do you have a portable phone (or similar device) near your amp? If so, try to move it.

 

You can also try to (if feasible) to lift up the amp and move it slightly in different directions to see if the hum decreases.

 

I get hum when I play at very loud receiver levels. To avoid it I found that turning up the amp til around 3 o'clock (below clipping) and keeping my receiver on a low volume setting helps, but then I am usually listening through speakers.

 

You could just turn up the volume without music and listen at what level hum appears.

 

Perhaps playing with the gain switches/settings underneath the amp will help to get a good volume on headphones with a lower main volume control setting.

post #3919 of 5933

Ho Oskari,

 

And I always thought the Philips Co invented the Phillips screwdriver! After all, they invented the compact cassette and the CD....

 

 

phillips-screwdriver-patent (1)

The screw was invented in the early 30’s by Henry F. Phillips, a Portland, Oregon businessman. He knew that car makers needed a screw that could be driven with more torque and that would hold tighter than slotted screws. Car makers also needed a screw that would center quickly and easily, and could be used efficiently on an assembly line. The Phillips screw was designed so that it could be driven by an automated screw driver with increasing force until the tip of the driver popped out without ruining the screw head. So what many consider a design flaw is actually a feature (at least if you’re a car manufacturer).

 

Looks like an interesting radio in the background. Blaupunkt?

post #3920 of 5933
Quote:
Originally Posted by mordy View Post
 

Looks like an interesting radio in the background. Blaupunkt?

 

Surprisingly enough, it's a Philips radiogram, used to belong to my grandparents.

post #3921 of 5933
Quote:
Originally Posted by mordy View Post
 

Just as a precaution, some tubes are more sensitive to RF noise than others. Do you have a portable phone (or similar device) near your amp? If so, try to move it.

 

You can also try to (if feasible) to lift up the amp and move it slightly in different directions to see if the hum decreases.

 

I get hum when I play at very loud receiver levels. To avoid it I found that turning up the amp til around 3 o'clock (below clipping) and keeping my receiver on a low volume setting helps, but then I am usually listening through speakers.

 

You could just turn up the volume without music and listen at what level hum appears.

 

Perhaps playing with the gain switches/settings underneath the amp will help to get a good volume on headphones with a lower main volume control setting.

The bad thing is, the hum starts very low, and as the brighter the tubes get, the louder the hum. In fact, I can turn the volume down to zero on the Little Dot 1+, and i'll still hear it hum loudly when my music is turned off. 

 

I don't have a cell phone or anything else similar near the little dot.

 

Could you show me how to get to the gain settings?

 

I'll try moving it around though right now.

post #3922 of 5933
Quote:
Originally Posted by mordy View Post
 

What is not enjoyable is that the wires on my spider web adapter break all the time when I move the adapter. They break at the soldering points at the Vector adapter.

 

What kind of wire is the thickest and most flexible that can be used with the Vector adapter (fitting through the little holes on the tabs) without soldering and just using the pressure of the tabs? Presently I use solid 22 gauge wire. Would stranded wire be better?

 

On my 6DJA adapter I use a breadboard with 30 gauge wirewrap solid wire without soldering. This seems to work better, but it seems to me that the wire is too thin to resist breakage (which already happened).

 

I am just winging it as I go along!  lol. I have very little experience with projects like this and would suggest that you always follow TrollDragon's advice rather than copy what I have done. That said, I am currently using solid core 28 gauge wire to connect my Vector adapters to the breadboard. However, very little thought went into this decision as it was simply what I had on hand, plus some 30 gauge wire, and figured that the 28 gauge would be a bit more durable. And so far, I have not had any wires break. However, I have been thinking that I should replace these wires with something better. And stranded 22 gauge would be both more sturdy and more flexible.

post #3923 of 5933

Hi Mikelap,

 

http://www.head-fi.org/t/353051/best-sounding-6sl7-short-glass-version-tubes-advice-need-it-pls

 

Thanks for the link - read the whole thing, not too long. But it was written long ago, in 2008. Again, no mention of Russian and Chinese tubes.

 

Wonder what happened to the guy with 2000-3000 tubes......


Edited by mordy - 11/10/13 at 9:22pm
post #3924 of 5933

I have lots of 6080 tubes with "Delta 6080" labeled on them. does anyone know what the original manufacturer?

post #3925 of 5933

I decided I'll go ahead and buy a pair of 6Dj8/ECC88 U.S.A. made tubes as well, when I get paid <onday lol.

Even though i'm on a high school job budget, these posts are pretty compelling investments imo.  

 

After I buy the 7 pin socket adapters, what pins do I put in to make it work right? And which ones do I bend or cut off?

 

 

Oh, and the Sylvanias stopped humming too.

post #3926 of 5933

You could drive both channels with one 6DJ8 double triode with connections like this.

1000

You just need to be handy and creative...

post #3927 of 5933
Quote:
Originally Posted by Artsi View Post
 

You could drive both channels with one 6DJ8 double triode with connections like this.

1000

You just need to be handy and creative...

So if I decide to buy this 9 pin adapter for the Little Dot 1+, does it requier any soldering? And more so, how do I hook it up? Any tools that are needed?

post #3928 of 5933
Quote:
Originally Posted by Sony Slave View Post

So if I decide to buy this 9 pin adapter for the Little Dot 1+, does it requier any soldering? And more so, how do I hook it up? Any tools that are needed?

 


www.head-fi.org/t/686893/how-to-make-an-adapter-to-use-double-triode-tubes-with-little-dot-mk-ii
If you use only 6DJ8 you can forget switch. MK I+ is little trickier to do the box since it has decorations.
post #3929 of 5933
Quote:
Originally Posted by Artsi View Post
 
Quote:
Originally Posted by Sony Slave View Post
 

So if I decide to buy this 9 pin adapter for the Little Dot 1+, does it requier any soldering? And more so, how do I hook it up? Any tools that are needed?

 


www.head-fi.org/t/686893/how-to-make-an-adapter-to-use-double-triode-tubes-with-little-dot-mk-ii
If you use only 6DJ8 you can forget switch. MK I+ is little trickier to do the box since it has decorations.

Could I just cut off the pins and set it to E92, or is it absolutely necessary to do use the adapter?

Perhaps Gibosi could show us a picture of how his Little Dot looks with the 6DJ8 tubes...

post #3930 of 5933
Here is a good text about 6SL7 and 6SN7 tubes.
http://boneshifi.blogspot.fi/2013/07/the-6sl7-and-6sn7-family-of-tubes.html

And here is another.
http://www.hifi-tunes.com/the-evolution-of-a-constant-glow-in-high-fidelity/
Edited by Artsi - 11/11/13 at 12:21pm
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