[serman005]

  How do these pair with stock HD-800's? I just bought them and don't really have an amp for them. Thanks!

Am considering the Mk II and wondering what the input jack type is. Can I just run a 3.5 mm to 3.5 mm cable from the ipod to the back of the amp?

 

[drteming]

  Am considering the Mk II and wondering what the input jack type is. Can I just run a 3.5 mm to 3.5 mm cable from the ipod to the back of the amp?

 
RCA inputs, so you'll need a 3.5 mm to stereo RCA cable.

 

[serman005]

   
RCA inputs, so you'll need a 3.5 mm to stereo RCA cable.

Ah--okay. And forgive me for my ignorance, but that connector type won't degrade the sound quality (?).

 

[drteming]

  Ah--okay. And forgive me for my ignorance, but that connector type won't degrade the sound quality (?).

 
Nope, it shouldn't.  The output coming out of the ipod is single ended.  Even though you got 2 separate ground connectors for the RCA input, the connecting cables in the MK II goes to a common ground.  People talk about possible crosstalk with a single ground, but I'd never been able to discern any.

 

[serman005]

Thank you. Last questions. What are the differences between the different iterations of the Little Dot--very confusing-- and are you happy with yours? Thanks again for the feedback!

 

[drteming]

Thank you. Last questions. What are the differences between the different iterations of the Little Dot--very confusing-- and are you happy with yours? Thanks again for the feedback!

From what I've seen, the layout changes between the versions, and the later ones can take a different power tube. The current one is version 3, which is the one I have, but as I have posted previously, I've gutted almost the entire thing and rebuilt it with better components.

I also strongly recommend you build an adaptor with resistors across a switching plug like I did so that you are not exposing your headphones to pretty significant DC voltage on startup.

 

[serman005]

From what I've seen, the layout changes between the versions, and the later ones can take a different power tube. The current one is version 3, which is the one I have, but as I have posted previously, I've gutted almost the entire thing and rebuilt it with better components.

I also strongly recommend you build an adaptor with resistors across a switching plug like I did so that you are not exposing your headphones to pretty significant DC voltage on startup.

Thanks for all that!

 

[progrockrob]

quick question - how does the power output increase as the impedance increases?  usually isn't it the opposite?

 

[jleewachter]

  quick question - how does the power output increase as the impedance increases?  usually isn't it the opposite?

 
I've always wondered the same, but I've been too lazy to do the research. I'm sure it has something to do with the OTL/Push-Pull architecture, whatever the hell that all means.

 

[OctavianH]

Tried the MK2 with my new pair of Beyerdynamic T1.2 (600Ohm). They sound incredible and I have to say that it is by far the best setup I had until now. So my worries related to Beyers is gone.
 

 
But keep in mind the following:
- T1.2 has a more bass than original T1 but still they haven't lost the detail
- T1.2 has less treble and does not sound harsh at all
- Comfort is incredible, compared to T5p (my other Beyerdynamic I own), foam pads are incredible
- T5p cannot touch the T1, they are in different leagues even if they have the same price
- T1.2 are not "unforgiveable" as some say, I tried different recordings and I have to say that some "poor" ones sounded better than on my HD600 which are "veiled" and bassier and should be more forgiving
- Drivers used were Mullard M8161 - the most neutral ones I own
- I prefer a clean and detail sound, and I am not enjoying too much bass, but precision
 
I tried the T1.2 directly in NFB11 (neutral) and it does not sound bad, but worse than on tubes, more "metalic" and cold. 
Plugged directly on iDAC2 sound better than on NFB11 (warmer somehow) but not as good as on MK2. So we have a winner, and it seems that again the price is not the first thing to consider when amplifying high end models like this one.
 
So in conclusion, 600Ohm headphones work fine with MK2, no problem at all. And T1.2 is an incredible pair, far away from T5p and most probabily an improvement to original T1 in terms of bass and overall musicality.
 
I hope my comment is useful for someone.

 

[HOWIE13]

@OctavianH
 
Thanks, that is indeed most helpful. 

 

[hiilari]

Hello, greetings from Helsinki Finland,
 
got my Litte Dot Mk II and after a few hour burn-in started listening. It sounds great, and definitely has its own characteristics compared to my other non-tube amps. But my unit has a problem: there's a clearly audible low-frequency ground hum or buzz. Especially with sensitive headphones like Bose QC 25 it's annoyning even if most music tends to block the hum so I only hear it between songs. The hum is completely independent on volume level, gain switch positions or wheter anything is connected to the input or not. It is in both channels with equal volume. On older vacuum tube radios this type of low buzz/hum is sometimes remedied by replacing power supply filter caps, thus thinking if my Little Dot has a power supply issue. Please help: is my unit faulty, is there an issue with the power supply, are the stock tubes poor quality?
 
Thanks in advance!

 

[DjBobby]

  Hello, greetings from Helsinki Finland,
 
got my Litte Dot Mk II and after a few hour burn-in started listening. It sounds great, and definitely has its own characteristics compared to my other non-tube amps. But my unit has a problem: there's a clearly audible low-frequency ground hum or buzz. Especially with sensitive headphones like Bose QC 25 it's annoyning even if most music tends to block the hum so I only hear it between songs. The hum is completely independent on volume level, gain switch positions or wheter anything is connected to the input or not. It is in both channels with equal volume. On older vacuum tube radios this type of low buzz/hum is sometimes remedied by replacing power supply filter caps, thus thinking if my Little Dot has a power supply issue. Please help: is my unit faulty, is there an issue with the power supply, are the stock tubes poor quality?
 
Thanks in advance!

Absolutely no hum or buzzing on my unit. I've switched all tubes at once, so don't know if the stock tubes are prone to it.
Have you tried to plug it at different socket? Also try to move it away from any other electrical appliances, sometimes there is an interference from other wifi units.

 

[hiilari]

Thanks for reply. Good to know the ground hum isn't there by design. I tried to move my amp far away from interference but that didn't help. So perhaps I try switching tubes next. I have a big box of them at home, but nothing that fits this amp... Next after that is to see if oneof the power supply filter caps is dried or faulty. 

 

[hiilari]

After some experimenting I have resolved this one. Changed tubes and placed the devie elsewhere. However, some ground hum is still available with Bose QC25 phones as they are so sensitive. With the much less sensitive HifiMan 400i hum is inaudible. I'm still in the middle of burning the amp in, or just getting used to the sound, but already now the sound is above all expectations. In fact, the sound is so much better in ways I didn't even anticipate. Just love it!