[Impulsive]

Quote:

 
I have a constant filling that my DT880 (600ohm) would benefit from extra power (at least 500 mW). 
Passport says, MKIII delivers 350mW on 300/600ohm load. Looks like this is the minimal requirement for these headphones, as I have to push my MKIII to the limits from which the hiss noise starts bothering me (80% on gain 10).

There is something weird about it.
I do not know output power of your source, but mine MK III loaded with 6H6P-I is currently set at 20% while my DAC (E-MU 0204) volume is set to 90%
If i were you, i would check mine gain settings and then inspect your souce.
Because if amp is on gain 10 running at 80%, your source must be giving incredibly small audio output.
My MK III runs at 80% when i set volume on E-MU to 10% and still not so much noticeable noise btw...
 

 

[mordy]

Hi AlexRoma,
 
Thank you for pointing out that the Voshkod 6J1P-EV tubes need an extra long burn in perriod. I now have around 120 hours on my 1973 tubes and they sound very different compared to before. The bass, even though still very powerful, is much smoother, and the irritating sharp highs are gone.
The entire presentation is more soft, and now the the highs even tend to be a little dark through my Audio Technica ATH-AD700 headphones.

 

[AlexRoma]

UPDATE on : I have a constant filling that my DT880 (600ohm) would benefit from extra power
 
I had found the reason -> both power tubes had been running half-dead. Looks like they had exhausted their life resource, came close to their death, but not died yet, a kind of tube-coma if you like.
 
I had replaced my 6N6P power tubes with the backup ones, the problem is gone. There is no more need pushing the amp over 50%. The gain increase is frightening .
 
Sorry for bothering you ... **** happens... 

 

[Impulsive]

hmm.
wow.
both tubes died simultaneously.
very weird.
I am glad you are now enjoying your amp again

 

[AlexRoma]

I had not checked which one died of the two, just replaced the set with my backup matched pair and forgot it. This 6N6p are cheap and common in Moldova (4$ for both). BUT 6N30p series are very rare tubes even here...

 

[Impulsive]

Well, i presume that each combination of driver + power tube represents each channel, so obviously if right channel wasn't louder than left or vice versa, probably both tubes died simultaneously.

 

[hal55]

Can anyone advise if Amperex 6ak5 are bass heavy or not. I've read that the "W' version is although brilliant in other areas. Is the non W similarly warm, liquid and sweet? Getting keen to start tube rolling but the choice is bewildering!
 
Thanks,
 
Hal55

 

[john57]

HI Hal55,
You will find your answer here at paragraph 3.2 which is the same tube you taking about and you will find more answers as well.
 
http://www.head-fi.org/forum/thread/563884/little-dot-tube-amps-vacuum-tube-rolling-guide 
 
 

 

[mordy]

Hi Hal55,
 
I have a pair of Amperex 6AK5/EF95 tubes that are made by Mullard from Gt. Britain, and their sonic signature sounds just like what is described in the above referenced tube rolling guide.
I recently acquired a pair of Amperex 5654 PQ (premium quality) tubes made in Holland. I have not had time to burn them in yet, but an early impression is that these tubes have superlative bass. The sound is very different from the British Amperex tubes I have - will report later when they are burned in.

 

[hal55]

Thanks to John and Mordy for their reples. The tube rolling guide was a godsend! While going over it my eyes lit p at the sight of the  Voshkod 6ZH1P-EV . Iuse the
I use the 6nip tubes in my Dac and they are brilliant so getting similar Voshkods for the LD will be great. Thanks very much for pointing me in the right direction.
Have no idea how to stop this thing going bold and underline since doing a copy and paste - sorry about that.
 
Hal55

 

[john57]

Hi Hall55
 
Yes the text editor that head-fi uses is kind of clunky at times.

 

[n5750547]

Hello all,
 
Anyone here have D5000 which they are using with the MkIII? Or would the Mk1+ be a better match for them?
 
Thanks
Phil

 

[mordy]

Hi G~Mann,
 
You wrote:
 
 Mordy, I'm still looking for that $8 a pair tube.  I just don't believe it will be found on Ebay.
 
Here is proof that you can find good tubes on Ebay cheap. These tubes I bought from England about a month ago.
 

1. Enlarge

Sell one like this

4 X MULLARD M8100 - CV4010 VALVES
Item condition:	--
Ended:	Jul 10, 201110:38:47 PDT
Bid history:	4 bids
Winning bid:	GBP 8.27
	Approximately US $13.41

 

 

[Cloud9Blue]

Just a very brief review of the three sets of driver tubes that I have tried with my MkIII so far.  The source is a HRT Music Streamer II+ and cans are DT990/600ohms and LCD-2.
 
Mullard M8100/CV4010
These are the tubes that I ordered the amp with.  
Bass:  Great energy, but slightly bloated
Mid:  Slightly recessed, but quite accurate and detailed
Treble:  These tubes give the most energetic treble out of the three, but this forms a bit of problem on DT990.  Some of the recordings exhibit significant amount of sibilance.
 
Voshod 6ZH1P-EV
Best of all three!
Bass:  Not as punchy as the CV4010, but leaner and much more detailed.
Mid:  Most detailed and forward presentation out of the all three.  Great for vocal, especially on the LCD-2.
Treble:  Treble is still very detailed, but the energy is just a little bit lowered comparing to the CV4010.  These tubes cure the sibilance on the DT990.
 
Hytron 6AK5 Black Plate
Not gonna go into too much detail, these tubes are the worst three by far.  It makes my DT990 and LCD-2 sound like pairs of closed can, as the soundstage is greatly reduced and the overall presentation is very muffled.  Maybe these tubes can get better over time, since I haven't even used them more than one hour.  But I just don't have the motivation to do that.  The Voshod and together with my newly arrived LCD-2 is just too mesmerizing.

 

[Deurklink]

Is it common knowledge that little dots come from Hong Kong aka China?
Didn't know this until i saw DHL's tracking output just now and it says that.
is this always the case?
I thought someone named David must be American or English, but i guess the zhezhe makes sense now