12AU7 aficionados please reply

[omigawsh_lollercoaster]

What do you have, had that are awesome? And why so impressive?

I've heard of:

RCA clear top
50's Mullard
7316 Amperex

as being good.

I got some alleged Telefunken: here, haven't tried them yet.

I found this list of alternate numbers for 12AU7:

12AU7/12AU7A
The only difference between the 12AU7 and the 12AU7A is the "A" version can be used in series string filament circuits due to it's controlled warm-up cathode. Otherwise, there is no difference.

6189/5814
Both of these are "milspec" versions of the 12AU7. They may also be marked with 12AU7WA. They both have thick mica wafers which give the tube extra rigidity which minimizes any microphonic problems. Their cathodes have been specially designed so they can withstand many on/off cycles and long periods in cut-off without any degradation of performance. The 5814 has a slightly higher filament current demand than the 6189/12AU7. Some (not all) Sylvania Gold Brand versions of these tubes have gold plated pins.

5963
This tube makes a decent substitute for the 12AU7 as the characteristics are almost the same. The 5963 has a slightly lower plate voltage rating compared to regular 12AU7. The 5963 has a max plate voltage of 250V while 12AU7 has a max of 330V. This tube has a specially designed cathode which can withstand long periods of time in cut-off without hurting the tube.

7730
This is a premium version of the 12AU7 made only by CBS/Hytron. This tube has very low noise characteristics and heavily plated gold pins. These were intended for critical test instrument applications, but due to their superior low noise performance, these make excellent choices for audio applications.

6680
This is the mobile communications version of the 12AU7 which can withstand +/- 20 % variations in filament voltages without any degradation of tube performance.

ECC802/ECC802S These are "premium" 12AU7's which were marketed by European manufacturers. I don't think that there was any difference in manufacturing technique, to create these, rather they are just specially tested 12AU7's that exhibit very low noise/microphonics and matched sections.

7316
This is an Amperex tube that was a premium grade 12AU7.

Are there others not on the list that you know?

What's the most you've paid / would pay for a really good tube?



I've seen as high as $995 a pair!

 

[gooky]

I think a 5963 is a good place to start. And at the prices they go for, it is clearly pound for pound the best tube. At least in my experience, with my stuff. But go ahead, and try them all and let us know what you hear. I've tried a lot of tubes, and that's what I've discovered so far.

 

[vcoheda]

have you seen this thread.

http://www.head-fi.org/forums/f113/l...-tubes-354857/

 

[omigawsh_lollercoaster]

Quote:

Originally Posted by vcoheda /img/forum/go_quote.gif have you seen this thread. http://www.head-fi.org/forums/f113/l...-tubes-354857/

Yes! Many times, it was the first thread I 'subscribed to'.

That thread and your HD800 balanced cable thread made 'vcoheda' another word for 'click here'!

It was my inspiration to get these:

Matched quad 5687s:

Matched quad 12AU7s:

I have some spare 5687s I picked up in the FS forums.

I'm thinking a nice pair or two of the best possible 12AU7s or similar and I'll be all set except for my ongoing obsession with the XDS1.

Those Amperex 7062s are on the short list!: Quote:

Originally Posted by shaizada /img/forum/go_quote.gif I rolled in some Amperex 7062 in place of the already excellent sounding stock 12AU7 tubes. The 3D soundstage exploded and is the reason behind my trembling hands and racing thoughts about the amp.

I'm also looking at the RCA clear tops and Mullards.

Have you decided on a favorite input pair?

 

[Seamaster]

I found myself like Mullard CV4003 the best so far (not the Kodak lables). They are full body, warm, detailed, and great bass. never big fan of Telefunken and Siemens, as they are super detailed and have a lot air, but lean at same time. In my rig, they are too bright for my tast even with HD650.

 

[omigawsh_lollercoaster]

Quote:

Originally Posted by Seamaster /img/forum/go_quote.gif I found myself like Mullard CV4003 the best so far (not the Kodak lables). They are full body, warm, detailed, and great bass. never big fan of Telefunken and Siemens, as they are super detailed and have a lot air, but lean at same time. In my rig, they are too bright for my tast even with HD650.

Thanks Seamaster,

I got some: Mullard ECC82/12AU7/CV4003 and: 5 NIB Amperex 7062/E180CC Tubes (PQ-Holland) to try out.

 

[Skylab]

Quote:

Originally Posted by Seamaster /img/forum/go_quote.gif I found myself like Mullard CV4003 the best so far (not the Kodak lables). They are full body, warm, detailed, and great bass. never big fan of Telefunken and Siemens, as they are super detailed and have a lot air, but lean at same time. In my rig, they are too bright for my tast even with HD650.

Ditto that big time - I own over 100 12AU7's, and the Mullard CV4003 are my faves.

 

[shaizada]

Nice amp buddy!

For the ULTIMATE preamp experience....get some Amperex 7062PQ for the input section and a pair of Mullard CV4004 for the preamp output section (Rear Right of the amp).

You can weld them in there if you like

Actually don't. Get some Telefunken 12AX7 Smooth Plates with the red tip on the top (in the input section, though there is a decent increase in gain compared to the 12AU7). You can change between some of the best sounds I've heard with the B52.

 

[Seamaster]

Check out part of my collection

http://h3soxg.bay.livefilestore.com/...Z/P1010196.JPG

http://h3soxg.bay.livefilestore.com/...N/P1010198.JPG

 

[MikeW]

havent heard the cv4003 or mullard long plate, but I enjoy the mullard short, and the Tung-Sol black glass is pretty superb as well.

 

[gooky]

What's the difference between the M8136 and the CV4003? I haven't heard either, but I do have a Mullard Long Plate. I know one tube may be better than the other, but is the difference great enough to seek them out? And please don't say, "Only you can answer that." That's why I spent so much in the first place!

Anyone selling any of the aforementioned tubes soon? (Staring at Seamaster intently.)

 

[Seamaster]

Quote:

Originally Posted by gooky /img/forum/go_quote.gif What's the difference between the M8136 and the CV4003? I haven't heard either, but I do have a Mullard Long Plate. I know one tube may be better than the other, but is the difference great enough to seek them out? And please don't say, "Only you can answer that." That's why I spent so much in the first place! Anyone selling any of the aforementioned tubes soon? (Staring at Seamaster intently.)

M8136 and the CV4003 are the same. You have one of the best already. But seems CV4003/M8136 long plate are more heavy duty. I am keeping all mine, sorry. Remember as 2003~2004, you can get $50 USD for a mached pair CV4003. Now, they are $125 above, and worse some that labeled Kodak may made in Mullard factory in Australia.

 

[gooky]

Good to know, thanks.

 

[Bones13]

I use a 1957 ECC82 Mullard in my Raptor, along with a (1953/1954) pair of Tung-Sol 5687 tubes. Very smooth, but not mushy.

 

[vcoheda]

in deciding what tubes are "best", a lot depends on the combination of headphone and source - not to mention as a secondary consideration ICs and PCs.