[BobJS]

A short while back I was displeased with my MKIV SE and was looking to sell it.   Fortunately for me, I had no takers, and closed the classified and decided to burn it in for 200 hours.  I'm not sure if it was the burn-in, or the act of actually playing with the various gain settings, but the sibilance I was originally unhappy with (with my 600 ohm T1) is gone.  I've also discovered (duhhhh) that ALL my phones sound great at one or another gain setting (Mad Dogs, HD-600, HE-500).  At the original default gain of 3 the lower impedance phones were lacking in bass.   No longer.
 
Now that I've decided to keep her, I'm going to try rolling some driver tubes.  They are a b*tch to remove ---- I assume the solution for you tube rollers is the same as the one I'm using for my Lyr ---- socket savers to elevate the tubes for easier removal?

 

[Brooko]

Quote:

Now that I've decided to keep her, I'm going to try rolling some driver tubes.  They are a b*tch to remove ---- I assume the solution for you tube rollers is the same as the one I'm using for my Lyr ---- socket savers to elevate the tubes for easier removal?

 
Unscrew the external tub enclosure - then they're easy to remove.  I just left mine off when I was actively tube-rolling (to decide which tube combination I preferred).  Once I'd settled on the right tubes, I then put the enclosure/guard back on.
 
When you are rolling - remember to give the tubes enough time to burn-in.  I don't believe in burn-in for most things - but the tubes definitely need a certain amount of time.  Even a week's regular use makes a difference IMO. 

 

[BobJS]

^^^ Thanks!
 

 

[Wildings]

After reading much excellent commentary, I yesterday ordered MK IV SE....which I will be using with vintage Grado RS 1's. I hope this is a good match, and am wondering if forum members recommend different tubes for this pairing? I listen to a lot of CD's, next purchase may be a Yaqin SD 32A tube HDCD player, but that's another matter. Thanks for your thoughts!

 

[bruce108]

Anyone opening the case? I'm a very happy Mk IVSE owner. But I decided to experiment with the EF91-2 range of tubes. See where I'm going with this? - sure you do. Managed to get one jumper off but couldn't get it back on in the right place. I'm not very dexterous, and that damn hole is too small. I've ordered a long curved pair of tweezers (as per a post here) so we'll see, but I'm not confident.
 
So is opening the case possible for a non-techie mug?
 

 

[Wildings]

While waiting for LD arrival, I read many of the prior postings, and have some uncertainty about the pairing with my RS 1's....further confusion after reading online manual. LD should arrive next week....I would appreciate advice on the gain settings to use. If I matters, I have a pair of the Radio Shack premium Gold audio cable series.

 

[HeatFan12]

Quote:

Anyone opening the case? I'm a very happy Mk IVSE owner. But I decided to experiment with the EF91-2 range of tubes. See where I'm going with this? - sure you do. Managed to get one jumper off but couldn't get it back on in the right place. I'm not very dexterous, and that damn hole is too small. I've ordered a long curved pair of tweezers (as per a post here) so we'll see, but I'm not confident.
 
So is opening the case possible for a non-techie mug?
 

 
How did the tweezers work out bruce?  I have never opened mine up, but be careful once inside.  Unplug it and let it drain due to the caps storing high voltages.
 
 
 
Quote:

After reading much excellent commentary, I yesterday ordered MK IV SE....which I will be using with vintage Grado RS 1's. I hope this is a good match, and am wondering if forum members recommend different tubes for this pairing? I listen to a lot of CD's, next purchase may be a Yaqin SD 32A tube HDCD player, but that's another matter. Thanks for your thoughts!

 
Quote:

While waiting for LD arrival, I read many of the prior postings, and have some uncertainty about the pairing with my RS 1's....further confusion after reading online manual. LD should arrive next week....I would appreciate advice on the gain settings to use. If I matters, I have a pair of the Radio Shack premium Gold audio cable series.

 
I would try lo, med and hi gain settings and see which one gives you the more full/robust sound.
 
Cheers!!!

 

[bruce108]

Quote:

How did the tweezers work out bruce?

 
Haven't arrived yet - I'll let you know.
 

 

[HeatFan12]

Quote:

While waiting for LD arrival, I read many of the prior postings, and have some uncertainty about the pairing with my RS 1's....further confusion after reading online manual. LD should arrive next week....I would appreciate advice on the gain settings to use. If I matters, I have a pair of the Radio Shack premium Gold audio cable series.

 
Don't know if this will help you as a guide (although plugging them in and listening would be best, of course).  I have 2 user manuals (2008 & 2009) and I believe I purchased my amp in 2008.  Been testing various gains with several phones.
 
 
2008
 

 
 
 
2009
 

 

[Wildings]

Recieved it a couple of days ago....I am absolutly astounded by the difference and improvement compared to line out from my CD  player...right out of the box with no break in!  As I mentioned in another post, I dont have the knowledge to be participating in the forum, at least I dont have anything to bring to the table, so to speak....but reviews I read here prompted me to buy the Little Dot, and I thank you all for that!  So, what do I do next?  My main sources are CD's from vintage Yamaha CDC-755, or streaming Slacker from Droid (no downloaded files).  A member suggested V-DAC II & V-PSU II....I looked at a Little Dot DAC I, not sure I understand the difference...and there is a new Little Dot DAC evidently, and I also looked at a Yaquin SD 32A VAcume tube CD HDCD.
I doubt anything I could do now would give me as much improvement and enjoyment as adding the headphone amp.  Thanks all, and best from NH, Tony B.

 

[fbxfbx]

Hi,
 
 and here's my own experience that I'd like to share. I bought my LD mk IV in a trip to Hong Kong, in a shop called Mingo. Beautiful shop, where I had the possibility of listening at the mk IV and the mk III side-by-side. I decided to go for the mk IV because I liked its precise sound signature and the generous headroom.
 Once unboxed at home it was sounding a bit harsh, becoming instead very smooth, yet precise, after a few days (I let it playing for many hours unattended), and all I can say now is that it's just a very lovely amp, very well built. The comparison at home with my other headamp (a homemade single ended OTL whose sound I know very well and represents my reference) also is very good, with the LD being just a bit more aggressive sounding. I normally use a pair of HD800s, I cannot be happier. This thing is smooth, powerful and precise, a real pleasure. In the next days the LD will find its place in my office desk, where by now I use a pair of HD280Pro.
 I also did a few measurements, with a software called Baudline, playing the test sounds through a Matrix Mini-i (another excellent piece) and sampling with an Edirol UA-25 at 96KHz. I attach the graph that I consider as the most meaningful, i.e. the harmonic spectrum on a 250 ohm load at 50mW of output power. Under these conditions the LD has a THD of 0.1%, very good I would say, and, even more important, the slope of the harmonics, which contributes to the sound signature is very good as well, decaying by about 20dB per octave.
 This beautiful little toy will give me for sure a very long time of earphone satisfaction. Recommended to all the serious listeners who don't want to exaggerate with the budget!
 
fbx
 
 

 

[BobJS]

I just got these inexpensive tubes in from Russia and they sound fantastic --- great on all counts, bass, mids, highs, soundstage :
 
4 x 6J1P-EV EF95 6F32 Voskhod Pentodes for Little Dot Amp MKII III 1980s NEW NOS
 
I don't recall if I found them myself or found a link from this thread.  The price went up a few dollars since I purchased and they're still dirt cheap.  Only down side is it took a month to get here.
 
 
http://www.ebay.com/itm/200898030188?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

 

[bruce108]

@HeatFan12
 
Tweezers arrived. Took the amp out into the sunlight and managed to change the jumpers first go: these tweezers are exactly the right tool for the job.

 

 

[bruce108]

Follow-up. So I installed a pair of GE 6CB6A [6CF6] Sharp-Cutoff Pentode Tubes (GE of Canada, "Japan" stamped on packet). Bought from dbtubes. All good, tubes working nicely & my early impressions are of a rich, but relatively clean sound - somewhere between the Mullard honey and the Western Digital's clear outlines.
 
But then I got to wondering where I heard about these, which are not commonly listed as an EF92 possibility for Little Dot. And a search of headfi doesn't yield results. Anyone running them?

 

[HeatFan12]

Quote:

@HeatFan12
 
Tweezers arrived. Took the amp out into the sunlight and managed to change the jumpers first go: these tweezers are exactly the right tool for the job.

 

 
Quote:

Follow-up. So I installed a pair of GE 6CB6A [6CF6] Sharp-Cutoff Pentode Tubes (GE of Canada, "Japan" stamped on packet). Bought from dbtubes. All good, tubes working nicely & my early impressions are of a rich, but relatively clean sound - somewhere between the Mullard honey and the Western Digital's clear outlines.
 
But then I got to wondering where I heard about these, which are not commonly listed as an EF92 possibility for Little Dot. And a search of headfi doesn't yield results. Anyone running them?

 
 
Great to hear those tweezers worked out great Bruce.  Seems like a great tool to have in the tool box.
 
In reference to the tubes check these:
 
Lots of info on different uncommon LD tubes and probably where you saw it
 
In post #1418 in this one gibosi breaks it down with a list
 
http://www.head-fi.org/t/364043/little-dot-i-tube-rolling/1410#post_9323456
 
 
Last 12 pages or so of this one has lots of info as well on uncommon variety tubes
 
http://www.head-fi.org/t/563884/little-dot-tube-amps-vacuum-tube-rolling-guide/975#post_9330447
 
 
Cheers!!!