[erich6]

I can confirm the Amperex JEP-6688's are great (mine are from 1964 production).  I also rolled a pair of NOS Lorenz E180Fs and they have the same tonality as the Amperex but slightly more expansive sound and bass control at the expense of slightly more microphonics (really only a little more which I only notice when something touches the amp).  Either pair is a great match.
 
I tried a pair of Telefunken E180F (1968 production) and I was very disappointed...they sounded the same if not worse than the Chinese stock tubes.  It could be I just got a bad pair though. Anyone else try these?
 
I'm still very impressed with this hybrid amp.  It's main issues are the poorly isolated power supply and short power chord...otherewise it's fantastic.

 

[erich6]

Ok i really like the current sound profile of 5532:s and my valvo e180f so i might buy the LM4562 to since they where cheap from trusted source.I have lt1364 on the way from china (hope they are not fake). Will LT1028 work do you think? Im also contemplating upgrading the power supply but im not sure to what since I dont want to spend to much money on it compared to the amp.

​I've been eyeing the Valvo as something to try.  They seem to be double the price of Amperex or Lorenz tubes though.  Have you been able to compare the Valvo's to other 6688/E180F tubes? 

 

[henkeman]

 
​I've been eyeing the Valvo as something to try.  They seem to be double the price of Amperex or Lorenz tubes though.  Have you been able to compare the Valvo's to other 6688/E180F tubes? 

I  have only got the Valvos:s and the chinese ones. I got mine from ebay.de for like $5 each including shipping so for me it was cheaper then the Amperex 6688 which I wanted to buy first hehe. But compared to the chinese ones its like lifting of a veil and all of the music sounded so much better and more balanced and clear.
 
I bought 4 pc of czech made E180F Tesla yesterday from ebay because they looked so well done quality wise and was cheap. I read some where that they where really good but kind of "forgotten".. Cant wait til I get them so I can compare them with the Valvo:s.

 

[erich6]

  I  have only got the Valvos:s and the chinese ones. I got mine from ebay.de for like $5 each including shipping so for me it was cheaper then the Amperex 6688 which I wanted to buy first hehe. But compared to the chinese ones its like lifting of a veil and all of the music sounded so much better and more balanced and clear.
 
I bought 4 pc of czech made E180F Tesla yesterday from ebay because they looked so well done quality wise and was cheap. I read some where that they where really good but kind of "forgotten".. Cant wait til I get them so I can compare them with the Valvo:s.

​$5 !!  I'm seeing them consistently for $80+ a pair.
 
Yeah, I was thinking about trying the Teslas also.  Look forward to your impressions.

 

[henkeman]

 
​$5 !!  I'm seeing them consistently for $80+ a pair.
 
Yeah, I was thinking about trying the Teslas also.  Look forward to your impressCurr

Currently there are a pair for like $16 http://www.ebay.de/itm/Rohren-2x-E180F-Valvo-neu-Gold-Pin-/132049274040?hash=item1ebec004b8:gfYAAOSw241YZo-H 
 
I think that "private persons" sell them much cheaper then commercial sellers. I dont know if they are different then the commercial ones. But mine looks exacly like the ones that sells for $80. There seems to be at least two different models but they are of the same high price from the commercial sellers.I have both models and they sounds about the same.

 

[henkeman]

I must say that my k550 have never sounded better then with this amp and good tubes no more trebleness and I cant believe that they are closed headphones. The soundstage got so huge but still natural! The tone is so nice, especially with rather calm "soundless" music with few instruments and vocalists(for more energetic music I prefer the open cans). Its like a pitch black background and the sounds/music just emerges from nothing at goes back to nothing so effortlessly with details that Ive never heard before, so natural.
 
They are only 32 ohms but this is the most synergistic combo I tried so far (before I didnt like my k550s so much). Tried Fidelio X2, AKG k612 and K712. But the k550 seems to benefit the most of this amp at least to my ears.

 

[Tom Steed]

I put a pair of 50yr old new mullard e180f's into this little box and it sounds great. I use sony mdr1 phones which are punchy on the mid to high range. They've mellowed a lot, i am going to invest in another pair of headphone, just need to find some that suit me.also i will be 'rolling' the op amp's and will have a few pair arriving soon. namely OPA3604AU and LM4562NA. I want to see what they sound like.

 

[edulov]

  I put a pair of 50yr old new mullard e180f's into this little box and it sounds great. I use sony mdr1 phones which are punchy on the mid to high range. They've mellowed a lot, i am going to invest in another pair of headphone, just need to find some that suit me.also i will be 'rolling' the op amp's and will have a few pair arriving soon. namely OPA3604AU and LM4562NA. I want to see what they sound like.

Small advice about rolling opamps. Wait about 30 sec after switching on but w/o sound playing at mid-high volume for your headphones. If you will hear some persistent silent noise or light whistling - electrical specs of opamps are not in sync with tubes and you can't use this pair. Wish you luck.

 

[Tom Steed]

Thanks for the heads up, they're cheap enough to play with i wouldn't try with muses chips though..

 

[lyncks]

Hey everyone
 
how does it do with the AKG K7xx? good match?
 
Cheers

 

[DJ The Rocket]

Some of my larger 3.5mm might be a close fit, but they fit.  It's adapters that can be a problem. It's a minor thing, but it's a thing.

If this isn't considered kind of hot, then the Schiit Magni is like in a freezer.  It's not even close to the temperature my NS08 gets.  Does such a temperature difference matter?  Is the NS08 designed to operate fine for decades at the higher temp?  Does my particular NS08 run hotter than yours for some strange reason?  Who knows. 

Huh. I thought it sounded absurd t say you weren't able to make the 6.35mm to 3.5mm adapter work, but I tried mine directly, and what do you know, it doesn't fit! I've been using a silver-plated extension cable ($16 for 6' on Amazon) and I can't detect any loss of sound quality with it, even on my Norse Audio cabled LCD2.2s, and I easily can with generic extension cables (though the 6.35/3.5 adapter there may be a weakest link: better than the 6' silver plated cable, but worse than the Norse).

EDIT: I also wanted to mention that this 3.5mm jack doesn't seem to do well with TRRS cables--even using a TRRS extension cable with a TRS plug on the other end, not talking about anything with a mic or remote on it. My TRRS extension works, but it serms to become unseated too easily. Don't see that issue with TRS plugs. It's unfortunate that my good extension is TRRS, I had assumed I'd be covering all the possibilities with this one cord, guess it's more complicated than that

 

[DJ The Rocket]

I  have only got the Valvos:s and the chinese ones. I got mine from ebay.de for like $5 each including shipping so for me it was cheaper then the Amperex 6688 which I wanted to buy first hehe. But compared to the chinese ones its like lifting of a veil and all of the music sounded so much better and more balanced and clear.

I bought 4 pc of czech made E180F Tesla yesterday from ebay because they looked so well done quality wise and was cheap. I read some where that they where really good but kind of "forgotten".. Cant wait til I get them so I can compare them with the Valvo:s.

Care to update us on the forgotten Teslas?

 

[henkeman]

Im sorry for the late post. I have continued my tube explorations and gotten a Little Dot MK3 so I have not been using my nobsound so much lately. Been burning in the Tesla:s under the weekend for about 20hrs so I can give my honest impressions.
 
When I first got them the treble was really shrill and bad and I didnt think any burn in could possibly change that.
I got disappointed and popped in the Valvos again and have not touched the Teslas since. Now I must say I really like them after the burn-in! No more harshness in the treble as heard before.
 
I do not have time to compare direct side by side with the Valvos but from memory I must say they are about as good. Separation soundstage and treble is really good and sweet! In some ways I prefer this amp with the Teslas to the little dot with russian Voskhod  6j1p-ev tubes. It has a nice fullness to the sound and the harmonics are so nice!
 
Im sorry I cant give a more detailed review of the tubes. They sound good and look really good and are nicely made to! At the price point I think it is a good buy.

 

[erich6]

  Im sorry for the late post. I have continued my tube explorations and gotten a Little Dot MK3 so I have not been using my nobsound so much lately. Been burning in the Tesla:s under the weekend for about 20hrs so I can give my honest impressions.
 
When I first got them the treble was really shrill and bad and I didnt think any burn in could possibly change that.
I got disappointed and popped in the Valvos again and have not touched the Teslas since. Now I must say I really like them after the burn-in! No more harshness in the treble as heard before.
 
I do not have time to compare direct side by side with the Valvos but from memory I must say they are about as good. Separation soundstage and treble is really good and sweet! In some ways I prefer this amp with the Teslas to the little dot with russian Voskhod  6j1p-ev tubes. It has a nice fullness to the sound and the harmonics are so nice!
 
Im sorry I cant give a more detailed review of the tubes. They sound good and look really good and are nicely made to! At the price point I think it is a good buy.

​Thanks for sharing your findings! Also, thanks for the comparison to the Little Dot Mk3 as I've been wondering if it would be an upgrade to the Nobsound.  I really like the sound I'm getting from this little amp but the microphonics and poor power isolation sometimes gets to me.

 

[henkeman]

 
​Thanks for sharing your findings! Also, thanks for the comparison to the Little Dot Mk3 as I've been wondering if it would be an upgrade to the Nobsound.  I really like the sound I'm getting from this little amp but the microphonics and poor power isolation sometimes gets to me.

For me I consider the LD3 an upgrade. But if its worth x6 the price of the nobsound I dont know. The nobsound is really a budget king in my opninion.
 
In some music I enjoy the nobsound more for example hard rock and more energetic music like Rodrigo y Gabriela which I think benefits from the fuller and actually softer sound of the nobsound. I guess the nobsound could be considered more fun but it doesn't suck me in as the LD3 does with my K712:s at least.
 
I mostly listen to jazz, classical, instrumental, bluegrass and female vocalists that benefits the biggest in realism in the sounds of the music and soundstage of the LD3. Other improvements that I could discern in the LD3 was a cleaner sound compared the nobsound sounds a bit grainy and noisy especially if you have to push the volume. It might be that a better ps or batteriy power could remedy that a bit. I guess one could say that the LD3 with the Voshods at least is more clean and hifi. But its a matter of degrees not like night and day. In the end I think its just a matter of how much one could enjoy the music one likes and hear beauty in it and how much one can spend on gear, to me the LD3 gives me more enjoyment.