[eucariote]

Quote:

 Has anybody else gone through a set of 12B4A's?  And if so, what tipped you off that they were the problem tubes?
 
--Ken

I had one go bad after a few weeks of use.  It sounded like light continuous static that would come in & out every few minutes.  After swapping the L & R tubes and hearing the static switch ears it was pretty clear that was the culprit.  Replaced it with another red NOS RCA 12B4A 3 months ago, it sounds well matched and all has worked fine since.

 

[replytoken]

 
Quote:

It sounded like light continuous static that would come in & out every few minutes. 

 
That would be a pretty good description.  Unfortunately, it is more noticeable when the amp has been playing for quite some time.  I did try to switch tubes, but I am beginning to think that after four years, my original sets have not aged gracefully.  They may test somewhat strong, but they seem somewhat noisy.  Oh, the joy of tubes! 
 
--Ken

 

[mrarroyo]

Hi Ken before you throw those tubes away clean the pins with an stiff brush and isopropyl alcohol. Also with the amp off and unplugged re-tighten the tube sockets. Lastly if you have to look for a pair of NOS GE red labeled 12B4A tubes. I have two pairs waiting for the day I buy another Mapletree.
 

 

[replytoken]

Quote:

Hi Ken before you throw those tubes away clean the pins with an stiff brush and isopropyl alcohol. Also with the amp off and unplugged re-tighten the tube sockets. Lastly if you have to look for a pair of NOS GE red labeled 12B4A tubes. I have two pairs waiting for the day I buy another Mapletree.
 

Hi Miguel,
 
Thanks for the advice.  I will certainly not dispose of the tubes, but I thought that cleaning them with a brush was not recommended (because of the outer coating on the pins?).  Do you find that your 12B4A's make a difference in the sound of your amp?  I know that Dr. Peppard thinks otherwise.  He also seems to think that these tubes last forever, but I am not sure that I fully agree.
 
--Ken

 

[mrarroyo]

Yes Ken I found  a difference with different tubes, not night and day but there. I also think the GE grey plate 5751 is a great driver tube for the amp. Good luck.

 

[Kevin.T]

New Ear+HD owner here!
 
I've read each 44 pages of this thread so far, and for the sake of keeping this thread's discussion going, let me ask this: What phones synergise well with the Ear+HD? We know about Grado and Sennheiser, but what about Beyer? AKG? Audio-Technica? Denon? Any models in particular? High and low impedance, is there a clear difference in drive-ability?

 

[MacedonianHero]

Quote:

New Ear+HD owner here!
 
I've read each 44 pages of this thread so far, and for the sake of keeping this thread's discussion going, let me ask this: What phones synergise well with the Ear+HD? We know about Grado and Sennheiser, but what about Beyer? AKG? Audio-Technica? Denon? Any models in particular? High and low impedance, is there a clear difference in drive-ability?

The beyerdynamic 600 ohms headphones sing with it! I've tried the DT770/600, DT880/600, and the T1s.

 

[stang]

Quote:

New Ear+HD owner here!
 
I've read each 44 pages of this thread so far, and for the sake of keeping this thread's discussion going, let me ask this: What phones synergise well with the Ear+HD? We know about Grado and Sennheiser, but what about Beyer? AKG? Audio-Technica? Denon? Any models in particular? High and low impedance, is there a clear difference in drive-ability?

I have actually heard every one of those with my MAD Ear+ HD, but not long enough to write any proper impressions. Beyerdynamic DT880 600ohm sound great with it, but I prefer the M3 for its better treble. Denon D5000 sounded better with the M3, also. There was too much bass with the MAD Ear+ HD.

 

[Kevin.T]

Thread dying... must ... keep alive...
 
No seriously, I've got a couple things I'd like to discuss in this thread, so please bear with me:
 
1. I've tried my HD-600s with the Ear+ HD these last couple of days and the results were... disappointing. I read pretty much everywhere that the amp was voiced with the HD-600 so I guess my expectations were high, but I feel there's something off with the pairing. With my 5751s*, they sound dull and detail-shy ; with my 12AX7s**, they get their bite back, but they have a bright and somewhat "glassy / hollow" presentation. It might not be a fair comparison, but I feel the Cayin HA-1A makes them sound much more natural/musical.
 
Anyone who has experience with the 600/650 and Ear+ HD combo can comment on this? What tubes do you use, and what presentation do you get? Maybe I just dont have the right tubes. I'd really love for my HD-600 to work just right with this amp... I don't want to get rid of either! ... (OTOH, nothing to say about the RS1i's with this amp.... everything is fine and dandy there!)
 
2. It says on the Mapletree website that the power output of the regular Ear+ HD is only 100mW. (link: http://hollowstate.netfirms.com/HD.htm) How can that be right? This seems really low for a mains powered amplifier. And If the 100mW thing is not right, why would Dr. Lloyd put that on his own website? Pardon my ignorance, I'm not very knowledgeable of electrics and I'm just trying to understand if and how this can be right.
 
Food for thought...
 
 
 
(* Tubes used: GE JG-5751WA TMBP + RCA JRC-5751 DMBP)
(** Tubes used: Raytheon 12AX7 Black plates + GE 12AX7 Grey plates)

 

[Olias of Sunhillow]

Hi Kevin -- ain't tube rolling fun? With my Ear+ HD, I've had somewhat similar experiences -- I felt the 5751s (Sylvania JAN, Sylvania JAS and others) were a bit flabby and unfocused with my HD650s, but quite nice with my RS-1s. The 12AX7s, on the other hand, were generally a bit overbright with the RS-1s (hard to believe, right?) but dead on with the Senns. Not wanting to need to switch tubes every time I switch cans, I've settled on a NOS RCA 7025 driver with both my HD650s and my RS-1s. The 7025 is said to have "the warmth of a 5751 with the gain of a 12AX7," and that it exactly my experience. It's not a widely known tube, so they're fairly easy to find in the $20-30 range for NOS.
 
Happy listening!
 
 
 

 

[MacedonianHero]

 
Quote:

Hi Kevin -- ain't tube rolling fun? With my Ear+ HD, I've had somewhat similar experiences -- I felt the 5751s (Sylvania JAN, Sylvania JAS and others) were a bit flabby and unfocused with my HD650s, but quite nice with my RS-1s. The 12AX7s, on the other hand, were generally a bit overbright with the RS-1s (hard to believe, right?) but dead on with the Senns. Not wanting to need to switch tubes every time I switch cans, I've settled on a NOS RCA 7025 driver with both my HD650s and my RS-1s. The 7025 is said to have "the warmth of a 5751 with the gain of a 12AX7," and that it exactly my experience. It's not a widely known tube, so they're fairly easy to find in the $20-30 range for NOS.
 
Happy listening!
 
 
 

I'm not a fan of the 5751 JAN Sylvanias...to hot a treble. But the 50s-60s NOS (Grey Plate and Black Plate Triple Micas) are my favourite. A close second is the 5751 GE 5-Star.
 
I typically only use the 12AX7s with my T1s from time to time.

 

[replytoken]

I am wondering if there are any EAR owners in the greater Seattle area that might be able to help me troubleshoot a few 12B4A tubes.  I can do this by mail, but it is easier in person.  Any local brethern of the orange glow?
 
--Ken

 

[Kevin.T]

Miguel,
 
Seeing your post above, were you saying you'd be willing to sell one of your pairs of GE red labeled 12B4A? Because if that is right, I'm interested!

 

[mrarroyo]

Hi Kevin, I have had those tubes (2 matched sets) for over 3 years! I have not sold them in anticipation of buying another Mapletree, now you got me thinking. Decisions, decisions!

 

[rehabitat]

you are SUCH a tease!