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"Looking for a tube" question...

sideways2

sideways2

Where the heck is S'toon?
Greetings!!

I am looking for a 12AT7 tube or its variations with these characteristics:

- rolled off top end
- fantastic midrange...the type of midrange that screams classic
- good, full bottom end
- does not sound thin

Anybody have any suggestions??

Right now I'm running a 1957 GE 5965 blackplate...it's almost there but the top end doesn't quite tone down the sibilance as much as I would like...but they are better than the RCA blackplate, the Mullard ECC81 and the Brimar CV4024 that I have.

Oh...I should add that my preamp can be configured for a 6DJ8\6922 tube as well :)

Thanks!!!

:music:
 
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Those tubes don't work that way. If they meet the manufacturer's specs they will all work the same. Don't be a victim of the metaphysical hi fi addiction. Like, what purity of water do I need when cleaning the panel to get the best sound? Ugh

If your design was for a 6DJ8 then that's what you should use.
 
Actually, the preamp is set up with an internal jumper that can be moved to either accomedate 12AT7's or 6DJ8's...awesome in that way!!
 
Humm, not many 6DJ8 or 12AT7 fit that "mullard" style eq curve, a 12AV7 "might" do it.

I'll think on this and see if anything else comes to mind, I am one who rolls tubes for a
different sonic flavor with good results, so yah don't buy into the all good testing tubes
sound the same deal, there are differences if your willing to work at it. At least for me.
(each piece of gear is different though so defiantly try out what you can)

When setup for a 6DJ8 the 6BK7, 6BQ7, 6BZ7 family of tubes are worth a try as well to.
(maybe an ECC85, 6AQ8 as the 6DJ8 "sub" as well, since a 12AT7 works)
 
You know...the mullard tube I have...not sure how good it is but compared the the ge, it has more sibilance on vocals and a smaller soundstage...mind you the midrange is a tad more natural in tone...go figure LOL!!
 
Bob91343 said:
Those tubes don't work that way. If they meet the manufacturer's specs they will all work the same. Don't be a victim of the metaphysical hi fi addiction. Like, what purity of water do I need when cleaning the panel to get the best sound? Ugh
Click to expand...

I've got to disagree with this. Different tubes of the same basic designation can sound very different. The electrical specifications have rather wide tolerances, and do not describe the entire operating envelope of a tube. I think the sonic flavors that different brands of tubes have are purely accidental. The manufacturers design the tubes to meet the electrical specs, and differently designed tubes can all meet the electrical specifications because the specs are just a few selected static points. What happens under other dynamic operating conditions is what gives the tubes their varied and distinct flavors. I'd think most people could readily hear the difference between a Mullard 12AX7 and a Telefunken 12AX7.
 
JonL said:
I've got to disagree with this. Different tubes of the same basic designation can sound very different. The electrical specifications have rather wide tolerances, and do not describe the entire operating envelope of a tube. I think the sonic flavors that different brands of tubes have are purely accidental. The manufacturers design the tubes to meet the electrical specs, and differently designed tubes can all meet the electrical specifications because the specs are just a few selected static points. What happens under other dynamic operating conditions is what gives the tubes their varied and distinct flavors. I'd think most people could readily hear the difference between a Mullard 12AX7 and a Telefunken 12AX7.
Click to expand...

+1 Been there done that and heard the difference.
 
If you have a silibance issue, I would look at all components in the system from the input source to the speakers. You can always turn down the treble to correct for an over accentuated high end. Oh, your esoteric preamp doesn't have any way to modify tone?
 
This will sound silly. But. Try polishing the tube pins. I bought little brass wire brushes for a Dremel tool. I po;ish tube pins with it. Then, I insert Q-tips into the drill chuck, dip them in rubbing alcohol, and polish the pins untill no more crap comes off the pins. Then I use soft polishing wheels for a Dremel tool, shoot them with ProGold and polish them again. When done, I clean the tube sockets and AC cord.

I can't hep with 12AT7 sonics. But for 6DJ8 types, Bugle Boy O-getter roll off the top; I like the A-frame Amperex 6DJ8, 7DJ8s; if you find some Tungsoram Yellow label E88CC accentuate the beat of music and don't high light pops and ticks on albums.

Best from Tucson Arizona
Bob
 
sideways2 said:
Greetings!!
Right now I'm running a 1957 GE 5965 blackplate...it's almost there but the top end doesn't quite tone down the sibilance as much as I would like..
:music:
Click to expand...

Hows about checking your cartridge alignment and be sure your stylus is not warn to the point of needing a new one. Sibilance can be caused by not having the cart aligned properly. You should look at the cart and stylus first before swapping tubes for a fix for that. Just my .02 - I'd be swapping carts for a cure for sibilance. Also rule out your speakers as well - could be an issue with a tweeter at a specific frequency, test tones will identify that easily.

Cheers,

Bob
 
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Morning!!

And hey Bob!! To answer you comment, it's without a doubt more so to do with the speakers...they are very detailed and as much as I like that, they can give you the worst too LOL!!

If I had tone controls that would more than likely solve any issue but seeing as my pre doesn't, then I'm opting for the other choice and that is tubes!!

I thought about changing my speaker cable too but I'm not sure what would be better...tubes are cheaper but cable could be the answer too!! I'm running Supra Classic right now...maybe something like Kimber or DNM might smooth out that top end??

As for 6DJ8's...I have a pinched waist GE tube that sounded nice I must admit...but I'm not usually a fan of the Amperex tubes I've heard...thin and way too much tizz at the top for me...not enough of that rich, full\thick sound that I like.

I've hadn't had too much experience with them though so please suggest away!!

One thing, isn't the 6DJ8 an Amperex design anyway...most being made by Amperex just relabelled?? Example...a Mullard 6922 but made in Holland?? If so how can the sound be any different??

Thanks again!!
 
Hello!

+3. I don't believe in most hifi voodoo, but I can definitely hear differences in preamp tubes. I rolled 20 12AU7 tubes in my Hagerman Cornet 2 before I found one that sounded the way I wanted. Peace. Robert
 
If I remember correctly ECC88 is a VHF cascode RF amplifier, 1957 Phillips.
For VHF RF amplification the main issues, other than tube noise is signal to noise ratio. Cascode is feeding the first triode into the second triode.

From that, we can see that ECC88s were not designed for audio use, not designed for left and right channel amplification and can guess that tube tester specifications might not be related to audio use.

I've played with ECC88 family tubes in power supplies, for AF amplification in phono amps, line stages and amplifiers. With out exception they had individual sound characteristics different from other ECC88. All of the TFKN<> E88CC have the same sound, but PCC88, ECC88, E88CC have different levels of coherent detail, with the E88CC the best.

Personally, I would rather experiment with the 12AT7 family rather than exploring the wide and deep family of ECC88 types of tubes, PCC88 to E288 is quite a span with quite a few manufacturers and different versions.

Best from Tucson
Bob
 
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