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Little Dot Tube Amps: Vacuum Tube Rolling Guide - Page 210

post #3136 of 10489

An update to the Strapping Switches...

Red switches toggle between EF92 and EF95 mode.

 

Red Up sets EF92 and bottom switches are bypassed.

Red Down sets EF95 and bottom switches toggle 1-7 / NS / 2-7.

post #3137 of 10489

Slick!

 

I assume you wired your switches to the pins for the jumpers and made a simple open/closed circuit? Ive been considering doing the same for awhile... I was gonna use a wire wrapping gun to punch the leads down (simple, secure and fast)... whats been killing me where to mount the switches on the MK1+

post #3138 of 10489

Thanks kvtaco17!

 

I just left the jumper in default EF95 mode since it doesn't do anything in that mode.

 

The switches are soldered via wire to the tube socket pins where they come through the component side of the board.

Here is the way I wired them up on the MK IV.

:beerchug:

post #3139 of 10489

Does anyone know if you can burn in tubes without music, in other words, can I burn in tubes just by plugging it into a wall and turning it on with tubes installed?

 

I brought the GE JAN5654W, Voshkod 6ZH1P-EV, and the  Tung-Sol 6AK5 from 1953, I tried to originally purchase the 1956 tubes. But they were already sold out. Do the  Tung-Sol 6AK5 1953 and 1956 tubes sound any different?

post #3140 of 10489
Quote:
Originally Posted by Sony Slave View Post
 

Does anyone know if you can burn in tubes without music, in other words, can I burn in tubes just by plugging it into a wall and turning it on with tubes installed?

 

 

No, you do not need to run music to burn them in. However, I have read that it is not good to run the amp without headphones plugged in. I like to listen to the tubes every once in awhile during burn-in, so I usually play music at a very low volume, and then turn it up when I want to listen.

post #3141 of 10489
Quote:
Originally Posted by TrollDragon View Post
 

An update to the Strapping Switches...

Red switches toggle between EF92 and EF95 mode.

 

Red Up sets EF92 and bottom switches are bypassed.

Red Down sets EF95 and bottom switches toggle 1-7 / NS / 2-7.

 

Love it! Good job Trolldragon.

 

Oh, and with respect to the GE 6DT6A, I got a little update: They sound very transparent and engaging but I must agree with kvtaco17 that the stage is similar to his 6DT6, although reasonably wide, quite flat.


Edited by Acapella11 - 9/28/13 at 9:50am
post #3142 of 10489

Received a pair of ECC88 today. These were described as a used pair of Mullards and were pretty cheap. However, while one tube has Blackburn, UK markings, the other has Heerlen, Holland markings, so to call them a Mullard pair is a bit of a stretch...

 

However, as they say, "When life gives you lemons, make lemonade", so no problem. I figure I can audition them one tube at a time, connecting the three pins for the second triode to a socket adapter installed in the empty socket. And in this way, I can get a taste of the Mullard sound and the Heerlen sound for cheap. And as they are used, they are already burned in! :) lol

 

Hope to get this accomplished later today or tomorrow....

 

post #3143 of 10489
Quote:
Originally Posted by gibosi View Post
 

 

No, you do not need to run music to burn them in. However, I have read that it is not good to run the amp without headphones plugged in. I like to listen to the tubes every once in awhile during burn-in, so I usually play music at a very low volume, and then turn it up when I want to listen.

 

Ok I see, thank you!

I'm about to purchase my Little Dot 1+ soon.

post #3144 of 10489

Thought some of you might be interested in seeing this up close:

 

Bent pins 1, 2, 3 and 9 with needle-nose pliers:

 

 

And then inserted into an adapter, starting with inserting pin 8 into adapter pin-hole 7....

 

 

Next, will disassemble the adapter and reroute pin 6 to pin 1 (to connect the grid) and pin 7 to pin 2 (to connect the cathode). And then I will make a simple wiring harness to connect the second triode, (bent tube pins 1, 2 and 3 corresponding to the plate, grid and cathode), to socket pin-holes 1 (grid), 2 (cathode) and 5 (plate) in the other socket. And just to be complete, I might try to connect bent pin 9 to a chassis ground.

post #3145 of 10489
Quote:
Originally Posted by Acapella11 View Post
 

Oh, and with respect to the GE 6DT6A, I got a little update: They sound very transparent and engaging but I must agree with kvtaco17 that the stage is similar to his 6DT6, although reasonably wide, quite flat.

 

As my experience with the GE 6HZ6 was similar, I am not surprised to hear this. It too had the GE sonic signature that I really like, but a rather flat 2-D sound stage. Again, the venerable GE 8425A is superior to both the GE 6DT6 and 6HZ6, IMHO.

post #3146 of 10489

Another question, if the little dot does not have a RCA cable/DAC going into it, is it still safe to burn in my tubes (with my headphones plugged in).

As of right now I do not have a DAC.

 

BTW my Voshkod 6ZH1P-EV tubes just came in , I will upload a pic once I get to my friends house. 

post #3147 of 10489
Quote:
Originally Posted by Sony Slave View Post
 

Another question, if the little dot does not have a RCA cable/DAC going into it, is it still safe to burn in my tubes (with my headphones plugged in).

As of right now I do not have a DAC.

 

 

I think that as long as your headphones are plugged in, everything should be fine. But still, I think you should "listen" to them with your headphones every so often to make sure they are no problems...

post #3148 of 10489
Quote:
Originally Posted by Acapella11 View Post

Love it! Good job Trolldragon.

Oh, and with respect to the GE 6DT6A, I got a little update: They sound very transparent and engaging but I must agree with kvtaco17 that the stage is similar to his 6DT6, although reasonably wide, quite flat.
Thanks Acapella11!
I needed a tube to try the EF92 mode on the switches and the 6DT6A's where handy... I find they are quite a bit louder in EF92 as I only need 10 o'clock on the volume as opposed to 12.

I still enjoy the sound of the USAF 6AH6WA's the best out of the few tubes I have.
post #3149 of 10489
The GE's aren't even the best of the 6dt6a's... The RCA are awesome if you like warmth and the Sylvania's are awesome if you want less warmth more dynamics and detail.
post #3150 of 10489
Well then, I'll have to dig up some RCA's for sure. Thanks!
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