[bloodhawk]

Some observations from all the tube rolling i have been doing over the last 2-3 days -

Im loving the TS 5998 + 6H13C + TS 5998 + 6H13C with RCA 6SN7 GTB combo for now. Next ill be trying the Bad boys and the CV181-TII's with the same power tubes.

Been trying to find the GEC 6080 / TungSol 6AS7G for reasonable prices, but its been almost impossible.

Yeah, the TS 5998's really bring out the Mid's and a nice extension on the high end. The 6H13C's are bass monsters
The RCA 6AS7's on their own are really really well balanced tubes, but i didnt like them when paired up with the 5998's. But im sure there are people who will prefer that combination. I wont be using the TS 7236's without the 6H13C's at all. I remember when i last tried my friends 7236 in my crack, the high was super sharp, good extension, but way too sharp.

ooooh boy, TS5998+6H13C+TS5998+6H13C with the Sylvania VT-231's makes the amps soooo much better. And this is without the mods. Cant wait to try out the CV181-TII's once they get here next week.

Some observations regarding the Tung Sol 7236 tubes ( I grabbed 4 of these NOS)

- 3 are dual round getters (Horse shoe?)

- 1 of these is a dual rectangular getter.

- All 4 are grey plates.

Observations -

- Out of the 3 round getter tubes, 2 have orange text printing. One is the standard Black text. Here is the interesting part, the orange text tubes, sound way more dynamic than the black text ones. They even Bias higher.
Black Text tubes Bias @ about 50-52 ish. Orange tubes are Biasing around 55-58ish.

- The Orange tubes actually sound better to me than the standard 5998 (NOS) that i have been using.

- The mids are definitely a tiny bit more forward, but there is more texture to the low end, and there is bit of more added mid/sub bass. This is without sacrificing the treble clarity / texture or the openness.

Also the order the tubes are placed in matter way more with the 7236's. Im guessing because of the
lower trans-conductance vs the 5998's.
With the 5998's i couldn't tell any difference. (2 x 5998's + 2 x 6H13C)
But with the 7236's, the 6H13C's need to be first in order - 6H13C + 7236 + 6H13C + 7236

 

[klnglim]

This is my PIMP MY AMP project.

Stage 1:
Gold meter and gold volume knob.





Stage 2: (future project)
Laser engrave or stencil with gold color for faded away Little Dot MK VI+ logo and marking for Power button.

Stage 3: (future project)
Sand blast the transformer cover, solid state rectifier cover, SE and balanced output. Then gold pate them all.
Also gold plate all six brass ring and the XLR connector to match with the overall gold on black theme.

Stage 4: (future project)
Replace the black rubber feet with gold feet.

Have u thought of using laptop cooler instead of upgrade internal fans? At least u don't need to use higher feet, more quiet environment, use separate USB adaptor to run the cooler better than share current from the amp, save u some cost as well

 

[klnglim]

This is really an excellent post, I hope Ur still alive from the mods you was onto lol.

Anyways I found that on the MK8, there is also a need for a fan as this unit can get nice and toasty hot as is in stock form

Along with internall moving the cables out of the sides, which is anothet story,
I just finished install of fan today and it was not as hard as the MK6.

Look:


I used the same controller posted for fan control,
and used this fan on ebay:

found heren eBay: http://pages.ebay.com/link/?nav=item.view&id=281381583178&alt=web

And I only had to drill four small holes for the srews to bolt on,
because the bottom already has enough slots for air to pass thru..

Here is the finished effect of the Led fan:


I have it on loweat setting and unit is now only slightly warm to touch on slowest setting.


Edit:
Retouched the visuals on my
Little Dot MKVIIIse .
Not many owners of the MK8se I see..

have you thought of using laptop cooler instead of install fan at the bottom of the amp?

 

[Topodomain]

Hi,

I'm thinking to get MK VI+, but should i also get Mundorff cap upgrade? What about balanced DAC's? NFB-1.38? Something from Gustard? What would be good match to VI+?

 

[rudra]

Hi,

I'm thinking to get MK VI+, but should i also get Mundorff cap upgrade? What about balanced DAC's? NFB-1.38? Something from Gustard? What would be good match to VI+?

Get the mundorf caps. I got mine factory fitted. I haven't used a NFB 1.38 but used to have a NFB 17.32 but prefer the Denafrips R2R. YMMV

 

[thompsontechs]

Something to think about when getting the Mundorf caps. There will be no room for the fans in the unit and it will got very hot! I got some usb fans and mounted them on the outside to combat the issue.

 

[bloodhawk]

Something to think about when getting the Mundorf caps. There will be no room for the fans in the unit and it will got very hot! I got some usb fans and mounted them on the outside to combat the issue.

Heres the solution to that (make sure you get new taller feet) -

Just finished installing the Audyn's -

https://imgur.com/a/y6gZP

Spoiler: Pictures

And wow didnt know better caps make so much of a difference in higher end amps. In the BH Crack all the upgrades maybe made about 5-10% difference at the MOST. Same with my friends Mainline, high end components barely made any super apparent difference. (And im talking Jupiter caps / Mundorf Supreme SGO caps)

In my LD VI+ running - 6H13C-TungSol 7236-6H13C-TungSol 7236 + PSVane C181-TII's , the soundstage is audibly wider with the Audyn 0.68 uF 630V caps. I will be honest, i really wasnt too optimistic about hearing any major differences. Since the VI+ already has decent WIMA MKP's which are almost as good as Mundorf MCap MKP's. With the stock caps, the AMP sounded super lively, maybe overly lively i guess, but it was super fun to listen to. Now its sounds smooth and lively, while retaining all the resolution and micro-dynamics.

But damn, glad to be proven wrong, now i cant wait for the Mundorf Mcap MKP 33uF 250V caps to come in, the going to complete all the mods, along with swapping out the stock Panasonic caps and the resistors.

Thank for all the helpful posts guys, almost pretty went through the whole thread, and lots of great info in there.

My flipping over the fans job could be done better, but these are cheapo fans, so i just cut a small hole to route the wire through. Ideally i would drill holes next to each fan and route the wires inside for a cleaner look. But i have something else panned for that

Question - Is there anything like "Burn in" for caps?

 

[rudra]

Something to think about when getting the Mundorf caps. There will be no room for the fans in the unit and it will got very hot! I got some usb fans and mounted them on the outside to combat the issue.

Not of a big deal as I use a laptop cooler.

 

[thompsontechs]

Not of a big deal as I use a laptop cooler.

I have one of those as well, and it was not sufficient for my needs, the amp still was very hot. There was not enough flow directed into the holes where the fans were. YMMV

 

[rudra]

look like I get a lot more mileage than yours . I have used the amp for 3 - 4 hours without any issues. may be we use different laptop coolers.

 

[xenithon]

Quick question. The Mk8 has tube protectors which comprises the bottom ring (attached to the top plate of amp chassis), stand-offs about the height of the tubes, and the top ring. The top ring can easily be taken off using allen keys; but does anyone know how to take off the stand-offs? Not too worries about leaving the bottom ring attached to the chassis (believe you have to take the entire top plate off in order to remove those).

 

[davveswe]

How good is the little dot mk VIII SE? And compared to other amps?

Thanks

 

[davveswe]

I have just bought a mk viii se.

I suspect there may be a minor fault on the circuit which I want to deal with as soon as possible.

It fires up fine and the bias currents on the left and right meters are 56mA and 58mA respectively.

However, after a few hours of use the left meter reading drops significantly. After about five hours I turn it off for five or ten minutes as the left meter is getting too close to zero for my comfort. After a rest, everything fires up fine again with nearly matching meter readings to start with, before the left one gradually drops again over a few hours.

I have swapped all the valves from left to right channel and the behaviour doesn't change.

What is going on here please?

(I am very much looking forward to the mods thread. I'm not going to spend as much as other people here have, but I will definitely be making the most cost effective mods at some point in the future.)

Many thanks!

Did you find out what the problem was? seems like others have the same problem?

 

[colliedoggy]

No! A powerful laptop cooler wasn't enough to solve the problem.

The unit is currently mothballed. I've been too preoccupied with other matters to address the problem.

 

[bloodhawk]

No! A powerful laptop cooler wasn't enough to solve the problem.

The unit is currently mothballed. I've been too preoccupied with other matters to address the problem.

Umm flipping over the fans to the outside of the chasis works wonders. Just needs much taller feet -

https://imgur.com/a/XLUO2