Little Dot MK VI / Little Dot MK VIII SE Owners Unite
Feb 28, 2014 at 6:29 AM Post #1,204 of 2,724

Hi G600, thanks very much for the photo of the replaced resistors. I took a good look at mine and there is one burnt brown on the right side, and the sound is just missing some volume and some magic on the right side..... so now I know why and can try to fix it. My amplifier is less than one year old, (still under warranty) but I do not want to send it all the way to China to get it fixed. I will have to do it myself or find a good technician in Australia.
 
Feb 28, 2014 at 6:50 AM Post #1,205 of 2,724
So I just bought 8 new resistors (Kiwame 5W 330 ohm Resistors) on ebay, have to ship over from Italy. Do resistors have to be installed in a certain direction, or can they go any way around?
 
Thanks again G600, you have been a great help to me by just showing a photo and telling us all what is going on with your Little Dot repair/upgrade. 
 
Feb 28, 2014 at 7:09 AM Post #1,206 of 2,724
There is NO direction for resistor.
Great stuff those Kiwame, nice buy. They smell quality, unlike those blue chinese failure.
 
No problem for pointing, if I can help you I'll be glad to.
 
Edit : I see your photos aren't better than mine :D
 
Feb 28, 2014 at 7:20 AM Post #1,207 of 2,724
MKVI gets pretty toasty with no fans on. I wouldn't say his temps are unusual. My fans died after several months and I used it for a few days while new ones were coming and I was worried something was going to melt.

True they do get toasty but mine was fine without fans after mods, these mods (rebuilding half the amp, reducing components on the PCB) dropped B+ drastically and the temperature did get lowered. That was the last time I saw the amp in once piece. The circuitry and sound is stellar but the enclosure and PCB ventilation is extreme small and poor but alas at the expense of the $800 asking price of this amp. For the amount of tubes this size each running at over 200vdc I'd rather gone with P2P, easy troubleshooting and much more ventilation.
 
  So I just bought 8 new resistors (Kiwame 5W 330 ohm Resistors) on ebay, have to ship over from Italy. Do resistors have to be installed in a certain direction, or can they go any way around?
 
Thanks again G600, you have been a great help to me by just showing a photo and telling us all what is going on with your Little Dot repair/upgrade. 

Depends on where you are I can do it for you if you want, free of charge obviously but I have to check my schedule.
 
Resistors have no polarity. 
 
Not worth getting it check by a technician this is a good chance to learn a bit of DIY yourself just make sure you change and touch the resistors only, nothing else.
 
The 5 watt blue metal film units are bog standard Chinese generics. In reality they are probably only rated for max 300vdc and about 3-4watts of heat disspitation. Rather poor for "power resistors".
 
Feb 28, 2014 at 2:41 PM Post #1,209 of 2,724
My MK VI+ has a good fan and has never been run without the fan. The resistor that has burnt is not the result of the amplifier getting to hot, I believe it is because the resistors are cheap and nasty and 1 in every so many just fails and cooks itself. Nothing else is burnt, just one resistor. I will watch carefully to see if the new Kiwame Resistors have any problems with burning, but I suspect they will not burn.
 
Feb 28, 2014 at 6:16 PM Post #1,211 of 2,724
  My VI+ starts at 40°C, and gains degree after degree : 90 minutes after startup it's 46°C.

46'C is nothing. My modded Darkvoice 336SE amp runs close to 60'C with all voltages to the tubes (plates, cathode) all within spec of the 6AS7G and 6SN7 datasheet. 
 
  My MK VI+ has a good fan and has never been run without the fan. The resistor that has burnt is not the result of the amplifier getting to hot.

Believe it or not resistors that are looking burnt and brown is because of over current to what the base specifications can handle and heat. I know from experience that the VI+ has various little hot spots inside, so while your ambient temperature is down, you can touch the outside enclosure and not feel much direct hot heat those resistors and other components inside (especially squeezed in between tubes) can get hot as hell.
 
  I had some resistors even in SS amps that looked a bit burned but still working and nearer been replaced.

Same here but since I have an OCD with opening up electronics and replacing with better parts hoping for a better sound increase lol I will always replace them.
 
Feb 28, 2014 at 7:30 PM Post #1,212 of 2,724
Hi DefQon,
 
Thank-you for both your offer to assist and your advise. As for assisting me, I am a resident of Canberra so I am a couple of thousand kilometres from Queensland, so it is most likely that I will be doing the repair myself. But as for your advise, thanks so much, I am glad to hear from an experienced and knowledgeable person. I will follow your advise and replace the 8 resistors and NOTHING else. Although I want to ask if there is any other thing I should check or assess while the circuit board is out of the unit? Do any other components get as hot as the resistors? And should I consider fitting a larger fan or somehow increasing the air-flow? I want to fix this amplifier and make it last, that is why I spent extra dollars and had Mundorf Capacitors fitted when the amp was built, to hopefully increase the sound quality, but mostly to make it last a long time. But here I am with a six month old amp that has a burnt resistor. I asked David at Little Dot if I could supply him with any other parts to upgrade the unit when it was being built, but he said the capacitors and silver wire was all that was needed. I would have been happy to send some resistors as well at the same time that I sent the capacitors and wire, but it is to late now.
 
Mar 3, 2014 at 8:46 PM Post #1,213 of 2,724
Hey guys looking for suggestions for ss amp...
 
So my current set up is Senh Hd-650 balanced, Little Dot MK VIII SE and W4S Dac 2.
 
Not to say that I'm not happy, I was just wondering how solid state would sound.  For my first set up I've been blown away and this will forever be the basis for my judgement in future upgrades.  I'm sure this up hill battle will go on for years and new plateaus will be set.
 
So for my eyes are pointed to HeadAmp's GS-X MK2... 
 
If anyone who has similar gear could let me know or suggest something else I'd be grateful.
 
Also considering some ortho or even stax can's, though I haven't pulled the trigger on anything specific.
 
What I'm looking for is the clearest sound with tight bass without fatigue.
 
Mar 3, 2014 at 8:59 PM Post #1,214 of 2,724
Early in my head-fi career, I had HD600 with the MKVI which is pretty similar to your rig. I went through an IEM phase and a Stax phase, SR007 mk1 to be precise, but ended up with HD800s and am waiting for imminent delivery of my GS-X mk2 which I auditioned and thought was a perfect match. The GS-X is fantastic, but the wait to have one made is not. I would try to buy a used one while on the waiting list to have one made if you are wanting one.
 
Mar 9, 2014 at 3:26 AM Post #1,215 of 2,724
Is with the stock tubes ?
 

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