Little Dot MKIII Tube Rolling - Page 178

Hello,

does anyknow know this tube and heard / can recommend this tube?

http://www.ebay.de/itm/6J3P-E-6BC5-6AG5-HF-Tetrode-Petode-Tube-NOS-Original-Pkg-Reflector-70s-/130618020202?pt=Vintage_Electronics_R2&hash=item1e6970d16a

There are two versions as I see so far:  6J3P  and   6J3P-E.  Seem to be russian production like the "famous"  Voskhod 6J1P (EV).

Tube type is 6ag5 which shall work in the Little Dot. They're that cheap it would be a shame not to try'em.

Or do you guys would recommend buying/trying the RCA, Tung Sol, Sylvania 6ag5 ones instead?

I've tried a few driver tubes now and this is how I'd rank them..

1. JAN GE 5654's

2. Mullard 8100

3. Stock 6ak5

4. Western Electric 403b

So yes the cheapest ones I bought (the JAN GE at 4 bucks a piece) sound the best to me and the most expensive ones I bought sound the worst to me.

#1 and #2 are quite close but JAN GE sounds slightly more balanced to me. I will be running the 8100s for a while longer to see if more time with them changes the sound though. I'd be happy using either one. The Western Electrics had weird treble and actually kinda harsh sounding to me.   My ears just did not like them. The stock tubes were fine just not as smooth or refined, but way better than the 403b's to me.

Pretty happy now and not sure if I should bother trying the Voshkods.

BTW I am using Electro Harmonix 6h30pi Gold power tubes and HD 650 headphones.

The Western Electric 403B sounded exactly the same to me as you describe. However, an earlier version is called 403A, and it may sound different. Supposedly the only difference between the two is that the 403B lasts longer. I have not listened to them for a long time, but remember that different batches of the 403B from the later 50's sounded better.

You do not give us the manufacturer of your stock tubes; mine were GE.

The stock tubes only marking is "6AK5" in white with a white box around it, very faint...so I am not sure.

I'm not sure how to interpret the numbers on the boxes or tubes to give me a date on the 403Bs but the boxes look very old. The JAN GEs are the only ones with explicit dates on them, all say packed in June 1985.

Hey,

you should definetly give the Voskhods a try! There's a reason why they're recommended by nearly everybody who tried them.. :)

And they're that cheap so you don't waste money really in case you don't like them.

Having listened to my selection of different tubes for a longer time I want to give a small overview of my favourites so far:

EF95

Voskhods and Mullard M8100 sound totally different but can't say which I like better. Both sound great in their own special way.

M8100 is warm and relaxed sounding, nice (and a lot!) bass, beatiful mids (vocals are great) and no harshness in treble. These are my favourites for small arranged soul and singer/songwriter stuff. Especially on female voices. Little bit lack of detail.

Voskhods are more detailed and brighter sounding, but absolutely fantastic overall. Very quick bass, nice mids, superb treble and detail. An absolute everyday allrounder for highest claims.

I got other EF95/6ak5(w) tubes here like RCA, Tung Sol, GE JAN 6ak5W, Raytheon, Lorenz... but haven't herad them enough for final conclusions. So far no tube of these sounded nothing like bad at all !!

EF92

Just got the Mullard EF 92 (just written EF 92 on it) and haven't heard them for a long time but: they're nice sounding pretty much out of the box with a wide soundstage, toe tapping kind of presentation style. Maybe less authoraty than...

the EF 91 Mullard M8083. This one really blew me away having expected almost nothing. WIDE soundstage, contoured and punchy bass, beatiful voices, absolutely detailed and superb treble to my ears. I would highly recommend them to everybody who thinks the EF95 models are too close sound, too much "in your face".

Have also checked the (to me) indentically constructured Mullard CV4014 and couldn't find a differnce. Look for a bargain, they're out there and these tubes are absolutely worth it being patient.

So far... I will give added opinions after having compared the EF 95 armada I haven't listened to extensively. Let me know what you think about my listening impressions!

Greets

Nik

Good info Nik thanks for sharing. Your right about the Voskhods for some reason they end up in my amp in the end. But ive found a few tubes that sound really good one of them being a western electric jw6ak5 ive never seen a tube built like these, theres no getter on top  its silvering is directly behind one of the blackplates and if you look at the other side the tube looks perfectly clear no silvering. But the sound was so good it was hard to stop listening. Has anyone else seen or have this type of tube.

Joe  

Quote:

Originally Posted by mordy 

Hi all,

 

Contacted David Zhe Zhe of Little Dot and asked the following questions (His answers are underlined and in italics)

 

 

What is the life expectancy of the Little Dot MkIII preamp assuming it is being used 3 hours daily? Are there internal parts that wear out or deteriorate over time similar to vacuum tubes having a finite life expectancy?

No.  Lifespan would be pretty much the same as any other consumer electronics ~10 years or so.
 

 

What is the reason for your recommendation of not keeping the amp on longer than 8 hours each time?

Possible heat buildup if placed in an area with low ventilation.

 

So just keep on enjoying the the Little Dot MkIII and don't worry about nothin'!

Mordy, Thanks for digging deeper into the matter. Sounds like heat is the main issue in determing life span of the units. looking into the capacitor lifespan its hour rating is based on maximum temp and voltage eg: 105 degree celcius and 250v. Being that our units dont run that hot the caps should also last a long time.

Joe 

 

Tung Sol also made some tubes of this construction with a half moon shaped side getter and the getter flash on the side of the glass with the top completely clear. Have a few of these and they sound great.

The EF95 tubes are quite small (some people call them peanut tubes!) but it occurs to me that the side getter tubes could be made even smaller since the top part is empty.

Quote:

Originally Posted by jsvilla93 

 

Mordy, Thanks for digging deeper into the matter. Sounds like heat is the main issue in determing life span of the units. looking into the capacitor lifespan its hour rating is based on maximum temp and voltage eg: 105 degree celcius and 250v. Being that our units dont run that hot the caps should also last a long time.

Joe 

 

 

I have a computerfan (since amp is close to computer) that keeps blowing wind over the tubes constantly (mounted on the side of the amp). It is really nice actually they keep quite cool.
 

Btw I would like to recommend for computer users to check out these threads http://www.head-fi.org/t/598998/how-cut-highest-treble-down-to-acceptable-level and to balance your earphones http://www.head-fi.org/t/413900/how-to-equalize-your-headphones-a-tutorial (which I posted my settings for the hd 650 in search my posts). It has had a tramendous affect on my sound.

After I balanced my HD 650 I will never go back. I would say this is the biggest lift in sound since I got the little dot mk iii. It has THAT big of an affect. Voices sound clearer, bass more defined and dynamic.

Hello,

here's a little update on my tube rolling experiences so far. My equipment can be seen in my signiture. Please keep in mind all impressions are absolutely subjective.

Will be updated by the time I got new impressions.

Greets

Nik

Hi Infinity650,

Could you comment on the best combination of power tubes and driver tubes? I found that the 6N6P tubes work well with tubes that have a too bright treble in comparison with the 6N6P-i power tubes. The 6N6P tubes seem to take away some of the undesirable brightness in certain tubes. Personally, I got the best results with the gold grid 6N6P tubes.

The 6n6p haven't arrived yet so I can't comment on them right now.

The best combination(s) so far (no ranking, just a collection)

Both pairs of 6zh1p-EV, Mullard M8100, Mullard M8083 all in combination with the 6h30 dr "Supertubes". But with the Electro Harmonix 6h30 gold pins the sound was practically as good. Just slight nuances.

Quote:

Originally Posted by infinity650 

Hello,

 

here's a little update on my tube rolling experiences so far...

Wow, nice list and great effort! I agree with you on a number of these. I've rolled through at least 10 different sets of drivers and 3 power tubes, and I think you're right on the money with these descriptions. However, if you want to continue along as I did to try and find the "ultimate tubes" for it (I've also got the MK IV SE), here's my ranking in order:

1. Amperex Bugle Boy EF92. This is the one with the bugle boy logo, and my sets were manufactured in 1966. These are by far my absolute favorite tubes. They're wide open, creating the biggest soundstage I've ever heard from my headphone amp. The bass is clear and tight, and everything just seems to fit into place perfectly with these.

2. Brimar EF91. These are slightly ahead of the Mullard EF91. I say slightly because they have their trade-offs. The Mullards have better bass and lusher mids, but the Brimars have more of a controlled presence even at higher volumes. The Brimars also have an incredibly clear soundstage.

3. Mullard EF91. See above.

4. Mullard EF92. Better overall sound than the EF91, but less definition in the soundstage.

I snapped a photo on my cell phone of some of these little guys, it's cool seeing how different each manufacturer's designs were. 

Also, those power tubes on the right are the 6H30P-DR supertubes.Unfortunately, they're of the newer post-1999 stock, but they still sound great. Infinity650 has got me thinking I should revisit the Mullard EF92 to remind myself exactly what they sound like, though....

thanks for the update. Looking forward to the rest of the tube comparison.