More choices ...when will it end! Pacific Valve Ming DA MC 84C07

[Kees]

Quote:

Well, Skylab ranks the LunchboxPro up there with the best he has heard so one would theorize I should be able to hear this difference in SQ and yet I don't.  Not saying there is no difference at all  in *sound signature*  but better SQ than my Denon surround receiver? Nope.

Tin ears and an attic for rent would account for not hearing it. 
Not appreciating the difference is of course your prerogative.
Both would be solely your problem though, so please don't bother us with it.
Thanks.
 

 

[moodyrn]

Please, lets get this thread back on topic. It has been completely derailed, and we shouldn't give him the satisfaction of responding to his remarks or comments any longer.

 

[Skylab]

Quote:

Well, Skylab ranks the LunchboxPro up there with the best he has heard so one would theorize I should be able to hear this difference in SQ and yet I don't.  Not saying there is no difference at all  in *sound signature*  but better SQ than my Denon surround receiver? Nope.

 
I don't think it's really accurate to say I ranked it up there with the best I ever heard:
 
http://www.head-fi.org/forum/thread/402585/review-summary-a-ranking-of-22-tube-and-tube-hybrid-headphone-amps
 
Ranked 19 out of 23.  Nice amp for the money.
 
Are you going to take me up on my offer to send you free tubes?
 
http://www.head-fi.org/forum/thread/499320/why-i-will-never-buy-a-tube-amp-again/15#post_6740912

 

[Nada]

Guys please desist feeding the troll  {wiki "Troll_(Internet)" }       

 

[Nada]

Ive found rolling NOS driver tubes in this amp is a delight, as far as creating  significant tuning of the sound signature is concerned.
 
For the driver tubes Ive gone over to 7025 and 5751 rather then the standard 12AX7, with thanks to Skylab for his generous guidance.
 
The 7025 I think has the same high gain (100) as the 12AX7 but is quieter.
 
The 5751 if i remeber has a lower gain of 70.
 
Has anyone else used these tube types?
 
If so any success in reducing hum? (Ive got no hum at listening levels on Denon D7000's)
 
Have you found any tube brands that are particularly noteworthy?

 

[BmWr75]

I traded a fellow for some 1950s or 1960s vintage used Mullard 12AX7s.  Am using the Ming Da amp to drive Beyer DT880s.  The amp has sounded to bright slightly too me with all other old tubes I tried, but the Mullards sound just right.

 

[Nada]

I got some Mullards and they sure are laid back - nice with the Denons too.

 

[Skylab]

Quote:

 
The 7025 I think has the same high gain (100) as the 12AX7 but is quieter.
 
The 5751 if i remeber has a lower gain of 70.
 

That's correct - the amplification factor of the 5751 is 70, versus 100 for the 12AX7.

 

[Pricklely Peete]

Some late 50's era RCA triple mica black plates are terrific tubes (5751). The Black Burn (plant) Mullard 12AX7/ECC83 are pricey but are also terrific. Off brand tubes like Electrohome (Canadian) or Rogers are often BB Mullards which makes them a little bit more affordable for exactly the same tube.
 
Peete.

 

[Nada]

Quote:

Some late 50's era RCA triple mica black plates are terrific tubes (5751). The Black Burn (plant) Mullard 12AX7/ECC83 are pricey but are also terrific. Off brand tubes like Electrohome (Canadian) or Rogers are often BB Mullards which makes them a little bit more affordable for exactly the same tube.
 
Peete.

Thanks Peete for those great tips.

 

[Skylab]

Another good value are the CBS/JHY triple mica 5751's. Right up there with the best and often much cheaper than other triple-mica NOS 5751's.

 

[Nada]

edited..troll free zone

 

[dw1narso]

subscribed (don't know why subscribe button does not work...)

 

[Nada]

Quote:

Another good value are the CBS/JHY triple mica 5751's. Right up there with the best and often much cheaper than other triple-mica NOS 5751's.

Another nice tip, thanks.
 
Whats with the triple mica thing? Is it to reduce vibration and microphonics?
 

 

[Nada]

I wonder if these are real GE tubes and if so if they are worthy of a listen?
 
 
Wells Gardner labeled, General Electric 7025 dual triode tubes, with gray ribbed plates, and a halo circle shaped getter above the plates. Made in U.S.A. These are a higher quality version of the 12AX7. No other type number other than 7025 appears on these tubes and these are a 1961 vintage based on the first two numbers of the date codes.