Some Noob Lessons and Questions on Tube Rolling with a LD 1+
Oct 11, 2014 at 9:22 PM Thread Starter Post #1 of 1

electroshock

New Head-Fier
Joined
Jun 8, 2007
Posts
7
Likes
0
Hello this is my first post after lurking for the past few months.
 
I have been playing with a LD 1+ trying to absorb as much as I can from this and other forums.  I thought I would share some of the things I have learned and some of the mistakes I made so far. My main means of using the forum has been through using the search.  This has saved time but it also means I missed key bits of info concerning some of the modifications. My biggest mistake so far has been making a 6DJ8 adaptor for the LD 1+ without realizing the
noise issue with this model. 
I used a Hammond box, the 7 pin test connectors from Radiodaze and 9 pin socket.  I bought a matched (2nd mistake) pair of Amperex Bugle Boy 6DJ8 ECC88 tubes from Ebay. These are marked a little different than other Amperex tubes I have seen as they have a treble clef mark separate from the standard bugle boy logo.


 
 
 After about 8 hours of break in the tube sounds great with all the sound stage and detail folks have talked about but there is a persistent small hum in the right channel that will not go away even with pins 8 and 9 connected.  I even tried connecting Pin 3 which is the cathode for other channel to ground but this just generated a much louder hum.
 
The best performing tube I have found so far is a $3 pair of Sylvania NOS untested 6DT6 tubes in EF95 with Pins 1 and 7 connected which I achieved by running a jumper on a set of 7 pin test connectors per Page 77.

 
 
 I am also running the Muse 02 DAC chip 
 
Just a couple of questions on stuff I have not figured out yet
 
Is there any solution to the 6DJ8 noise problem on the LD 1+ I may have missed?
 
Do the other options listed of Page 77 for the 6DT6 (6/7 pin mod and 2/7 pin mod) make any difference to the 6DT6 tube performance?
 
Will the 5687WA modification with the external heater work with the LD 1+ (I assume yes as gibosi has advocated for this mod).  Also is there a wiring diagram for this mod? I found the parts list that gibosi made but no diagram. I am hoping I may be able to salvage my box by integrating it with this mod.  If this does not work out would my box work with other LD models?  My box has the connectors set with a 45mm center distance.
 
Finally will the C3G mod work with the LD 1+ using the double adaptor modification?
 
Thanks for any additional insight the members of this forum can provide and also for all the help this forum has provided in the past. The intensive involvement of so many members is the reason I purchased a Little Dot. I started with the low end model so I can make most of my errors with this before blowing up MK III or MK IV! I am enjoying my first tube rolling experience thanks to the info available on the forum.
 
Best Regards Bill
.​
 

Users who are viewing this thread

Back
Top