[AdamZuf]

hey,but i offered a fair trade!

(moderators, would you please pass this thread to "gear for sale/trade" ?

oh.. and then Jude will erase the first posts in here saying: "THIS IS NOT A DISCUSSION FORUM"...and this one too

)

 

[Hirsch]

Quote:

Originally posted by AdamZuf (moderators, would you please pass this thread to "gear for sale/trade" ? oh.. and then Jude will erase the first posts in here saying: "THIS IS NOT A DISCUSSION FORUM"...and this one too )

No.

 

[AdamZuf]

lighten up, Hirsch!
i was kiddin'

wow, this thread really has almost nothing to do with 12AX7 !
would somebody balance things up?

 

[dd3mon]

5751 can be used in almost any application that calls for 12AX7's. Even in speaker amps good 5751s often outperform 12AX7's.

-dd3mon

 

[AdamZuf]

is there a reason that with headphone amps they won't???

 

[dd3mon]

Quote:

Originally posted by AdamZuf is there a reason that with headphone amps they won't???

No, the only disadvantage to a 5751 is lower gain than a standard 12AX7. The advantages are lower noise floor spec, lower microphonics, etc.. and most of the 5751 were made at a higher standard than 12AX7's and it shows up in the sound.

With my MG Head, I notice very, very little difference in the gain (supposed to be like 70-75% of a 12AX7) - but this difference could be magnified alot in a speaker amp. Most amps will have enough juice to compensate though (most setups don't require amps to be run at 75% of max power).

-dd3mon

 

[dd3mon]

The only 12AX7 variant that I haven't tried (and would still like to) is the ridiculously expensive Raytheon 7729

One member has one (it was a gift to him) - prefers it to all else in his MG Head.

I found a seller, but his $500 price tag was about $400 more than I'd be willing to pay for this tube

-dd3mon

 

[Hirsch]

Quote:

Originally posted by AdamZuf is there a reason that with headphone amps they won't???

No. You're overgeneralizing. In some cases a 5751 is compatible with a 12AX7 circuit. In some cases it isn't. A 5751 has a mu (gain) of 70. A 12AX7 has a mu of 100. If the circuit needs the extra gain, the 5751 won't work.

 

[AdamZuf]

Quote:

Originally posted by dd3mon Even in speaker amps good 5751s often outperform 12AX7's.

i missed the "Even" part

well i'm not feeling too well today...
Hirsch..i know & understand what you're saying, but not why. i was talking soundwize, based on that both types work well in the setup...

and $500 for a tube?!?!?!
i didn't know it gets so expensive...i'll get to try looking at that when i'll have something like Hirschs' Supra.. for sure i need a bit more money to get there now

 

[Born2bwire]

Quote:

Originally posted by kuma ok. just checked my mail box . Eric sorry, looks like Ian's email was the first one. I want to give these away to a good home since they are just sitting around here and i have no use for 'em. Ian, send me your land addy.

Son of a #@$%(&%!!!!!!

This is why I should never log out of head-fi.

EDIT: Realized I should contribute at least something other than my usual brand of nonsense.

My favorites: 1. Sylvania Triple-Mica 5751 Blackplate
2. Raytheon 5751 Triple Mica 5751 Blackplate
3. GE 5751 Blackplate

The first tube roll I tried I used a Mullard CV4004 tube. It's a good tube but is rather warm, too much for my tastes. The difference between the Sylvania and the Raytheon is very small, I feel that the sonic experience is just better with the Sylvie but can't quite place my finger on it (believe though it has more detail and more three-dimensionality). The GE has very similar characteristics as the others but is a leaner tube, has less midrange and bass. I think the GE is a good match for OTL mode since that usually beefs up the bass.

 

[Andrew Pielet]

In my amps, I use Jan Phillips 12ax7wa NOS. They are awesome for rock, and are not outrageously priced. As most people have already heard here, Tele's are the opposite of what I like. They are SMOOTH, but no slam for the rock. maybe my power tubes don't go well w/ them.
I bought them from Celestial sound, they might go cheaper than the website says(i live next to them, so I got them for a bit cheaper). Look under the accessories.

http://show.audiogon.com/cgi-bin/sh....estialsound&8&

Also, have you checked into the asylum yet?

http://www.audioasylum.com/audio/tubes/bbs.html

I must mention that the sum of two different tubes is going to be different then the sound of one tube itself. I have the Jan's paired w/ RCA cleartops for the sound I am looking for, but I can have 30 different sounds with a combo of all the different input tubes I have. You must test for yourself. I thought I would like Tele's (in my system) but they truly suck ( in my system).

 

[kuma]

Quote:

Originally posted by Andrew Pielet In my amps, I use Jan Phillips 12ax7wa NOS. They are awesome for rock, and are not outrageously priced. As most people have already heard here, Tele's are the opposite of what I like. They are SMOOTH, but no slam for the rock. maybe my power tubes don't go well w/ them.

A good call. for newer production, those jan/phillips 12ax7s are not bad. ( nagra preamp's stock tube )
In my rig, i've replaced those with telefunken as my system needed slightly more open top end than the stock tubes provided. I see jan/phillips can work easily in a system with a slightly warmish slant. Or want to add a sparkle on the top.

As far as 'slam', I didnt think I sacrificed too much for the bottom end drive. but, I agree, jan/philips' low noise floor, reliability and kick ass bottom end make 'em a good choice for some applications.

 

[kuma]

Quote:

Originally posted by Hirsch CV4004 is the tube designation. IIRC it's a British military designator for the 12AX7WA. Mullard made a CV4004 (and is definitely a likely source for vintage British-made ones).

Yep. I found out that the pair I'll be trying out is branded as GEC. ( i use their 12AT7 in my preamp and excellent )

again, they are said to have a different flavor from mullards variety which tend to have overly sweet voicing.

will see how they compare to the Tele.

 

[Orpheus]

i'd put in another vote for the Sylvania Gold Brand 5751 with gold pins, triple-mica, grey plates. grab it if you can find it under $50. it's the best of the best according to Joe's Tube Lore. i've used in my MG Head OTL, and i think i might actually hear a difference.... and that's saying a lot coming from me. thought i'm not entirely sure.

 

[AdamZuf]

i'm getting a lovely midrange in my EMP. i've heard that it's better then the OTL with midrange, so i'm wondering if the same tubes which are great for the MG will work as good for me, from the tonal balance aspect.
i would like the tube to have a solid bass, and focused highs, as i love to ride my music lately on high frequencies, my ears just follows easy to what's ever below, so i want accurate highs but not dominant, focused but delicate, as i want the lower frequencies to reach with no effort, but i would still like to stay as neutral as possible of coarse. i know this listening technique from my Sylvania 12AT7, which was a total lame on bass, but i still don't know if it was defected. i would like to see how i can evolve this technique with a tube that does have a good bass & perform well.
right now i'm using the a Penta 12AX7 (i got it with my ART, i understand this tube sucks), and the highs started to piss me off bad after a few days.