[ianmedium]

I would like a pair of Telefunken DF91's at some point but to be honest these are radio tubes made in their hundreds of thousands and they are simply not worth what some sellers are trying to sell them for. The most I would pay is $20 for a tube but that is pushing it.

So many of these types of tubes are out there as they were used in military radios. There are literally warehouses full of them. I am sure somewhere there is a large stash of Lorenz and Marconi's somewhere gathering dust!

I know the seller that sold me the Siemens once he found out there was a market for them jacked the prices up considerably! The Telefunkens I enquired about were DL92's but in truth they were re-branded Mullards so thinking on it I already have them!

 

[bmichels]

I have not done the tubes that need modification and have no interest in that part. I will leave that to you and GG. The combination I mean is the Phillips DL92/ Lorenz DF91 that I have loved for so long. 

AHHH I thought that you were using the Lorentz DF96 !!  
 
Now I understand: I was disappointed a little bit by the Lorentz DF96 + Philips DL92, and this surprised me because usually we have a similar taste .
 
Those DF91, I believe are quite hard to find isn't it ?  Expecially if you look for the Stuttgart made ones ?  Is the "stuttgart made" important ?

 

[bmichels]

some more porn before going to bed ?  

Decware Taboo MK3 headphone amp

 

[ianmedium]

AHHH I thought that you were using the Lorentz DF96 !!  

Now I understand: I was disappointed a little bit by the Lorentz DF96 + Philips DL92, and this surprised me because usually we have a similar taste .

Those DF91, I believe are quite hard to find isn't it ?  Expecially if you look for the Stuttgart made ones ?  Is the "stuttgart made" important ?

Apparently the Stuttgart made ones are much better, well that is the opinion of other types of tubes. Apparently the pre "SEL" ones are the ones to go for!

 

[woodcans]

   
I am very glad that you got your " precious " back.  Now you can have fun with us again...
 
What tube combo have you used for this new start ?

 
 
That made me laugh! And while funny, quite true. Ian, I am also glad you have yours back. 
 
GG, how much of a difference do you expect to hear without the impedance switch in the circuit?

 

[ianmedium]

I am sure I have no idea what you both mean :rolleyes:

[VIDEO]http://www.youtube.com/watch?v=Iz-8CSa9xj8[/VIDEO]

 

[GermanGuy]

as long as you use only one headphone now and in the future,  you can hardwire the impedance to the best sounding impedance, but as all of us have a tu-05 WITH impedance switch and as posted the sound improves and improves with better sources and dacs, this is NOT a limit or a bottleneck for the sound.
 
impedance set too low means bassy sound without detail and highs, set too high means less to no bass.
 
for example the pf viii with impedance adapter 270 ohm using my cayin ha-1a lost the whole magic, bass extension and cave like sound.
 
the hd800 with 16 - 120 ohm impedance setting using the tu-05 is much to dark, muffled sounding.

 

[woodcans]

I am sure I have no idea what you both mean

Spoiler: Warning: Spoiler!

Spoiler: Warning: Spoiler!

 

 
Well, I always suspected you had slightly 'pointy' ears. 

 

[ianmedium]

Spoiler: Warning: Spoiler!

Spoiler: Warning: Spoiler!

 

Well, I always suspected you had slightly 'pointy' ears. :eek:

People who have met me always say.. "he is not of this Earth"!!

 

[bmichels]

Ian, just for you :  http://www.positive-feedback.com/Issue67/nagra.htm
 
enjoy....
 

 

[ianmedium]

Very very nice, Thank you for the link!

I plugged in the Brimars yesterday, they have about four hours on them at the moment. Nice and quiet which is good! Sound wise. They have a very attractive sound signature so far. I thought the treble was rolled off a bit but as they open up it seems they have the detail there and shimmer. Bottom end has more weight than the Lorenz's and the mid range is rather lovely. I was in truth not expecting much from these but they are growing on me. I will do some more burn in today when I get back home them listen to Shawn Colvin live. Her guitar should sound full bodied but crisp and her voice slightly breathy. I actually think these might suite me more than the Lorenz's as they feel ever so slightly more intimate.. Will report back this weekend.

Thanks Andy for bringing them to my attention. Oh yes, I am really glad I go the stamps off mine!

 

[smial1966]

ianmedium,

I'm glad to learn that the Brimars have such a beguiling sound, but now you've put me in a delightful dilemma, as I was saving the 'stamped' Brimars as thermionic curiosities and haven't actually listened to them yet - oh the shame! But they might actually outperform the Lorenz and must now be used, so to heck with the decorative stamps, where's that soapy sponge?!?

Cheers,
Andy.

quote name="ianmedium" url="/t/632518/analog-paper-2-discussion-and-appreciation-thread/2160#post_9800080"]Very very nice, Thank you for the link!

I plugged in the Brimars yesterday, they have about four hours on them at the moment. Nice and quiet which is good! Sound wise. They have a very attractive sound signature so far. I thought the treble was rolled off a bit but as they open up it seems they have the detail there and shimmer. Bottom end has more weight than the Lorenz's and the mid range is rather lovely. I was in truth not expecting much from these but they are growing on me. I will do some more burn in today when I get back home them listen to Shawn Colvin live. Her guitar should sound full bodied but crisp and her voice slightly breathy. I actually think these might suite me more than the Lorenz's as they feel ever so slightly more intimate.. Will report back this weekend.

Thanks Andy for bringing them to my attention. Oh yes, I am really glad I go the stamps off mine![/quote]

 

[ianmedium]

Andy, just be careful with the sponge, the lettering is very delicate and I did lose a little off the edges of some letters but i must admit my stamps were not as nice as yours so it was no big deal to lose them. The come off very easily and only need moisture for a few seconds.

I have just got home so am going to run the amp for another three hours to give some more thoughts but your term for them, "Beguiling" is actually really accurate. They probably do not have the last ounce of high end (but that may change with more burn in, that has been my experience with burn in) but they are so sweet and musical.

 

[GermanGuy]

modder's paradise:
 
http://www.vt4c.com/
 
http://www.vt4c.com/shop/program/main.php

 

[GermanGuy]

as my modded tu-05 has two headphone output jacks (the rear 6.3mm Neutrik one and the front 3.5mm jack), i today modified my tu-05 again:
 
- the rear neutrik jack was and is connected to the 8 ohm pins of the output transformers
- the front 3.5mm jack is now connected to the 4 ohm pins of the output transformers
- i changed the connections of the impedance switch to now medium and high setting
 
as a result:
 
- i can use the vast majority of my headphones as before using the rear neutrik 6.3mm jack, impedance set to medium
 
- i can now use my hd800 connected to the rear jack, impedance set to high (due to the now smaller but nevertheless existing impedance mismatch slightly warmer sounding, but that can be perfectly compensated by setting the colorfly eq to the 'rock' setting)
 
- i can use the akg k3003 and the fad pf viii connected to the front jack, impedance set to medium (when doing my "big" mod, i will provide switches for all combinations possible with the output transformers):
 
Impedance range should now be something like that:
 

IMPEDANCE​	LOW​	MEDIUM​	HIGH​
REAR 6.3mm Jack​	8 - 32​	16 - 64​	32 - 200​
FRONT 3.5mm Jack​	4 - 16​	8 - 32​	16 - 100​

 
edit:
 
after some listening i have resoldered the impedance switch cables to their original positions and so low / medium setting.