Need 12AU7 and variants suggestions...

heiney9

I am looking at possibly purchasing an integrated tube amp that uses 12AX7's and 12AU7's as part of the driver/pre-amp circuit. I am very familiar with 12AT7 and 12AX7 and their variants but not too much with 12AU7.

Need some suggestions. Looking at 5814 5963 as a possible choices also.

Just some user experiences of some different brands/years, etc. If I pull the trigger I already have plenty of 12AX7's I just need to decide on a some 12AU7 or variants so I can use the amp when I recieve it. Not a done deal yet, but I'm working on it.

H9

VR3

rca clear tops, black plates
Mullard military grade

Probably the most popular 12au7 and the best sounding I heard in my Candela preamp.

heiney9

Thanks, could you be more specific on "Mullard military grade", lots of Mullards from the 50's thru the 80's claim military grade. Happen to have a year or perhaps plate structure or getter type. There is a bit of variety when it comes to Mullard tubes.

H9

heiney9

Right now these are on my radar

Raytheon 2 mica black plate 5814
Raytheon 3 mica black plate 5814 w/windmill getter
Raytheon 3 mica LONG black plate
CBS/Hytron JHY 5814 w/square getter
RCA 12AU7 Long black plate w/square getter
Valvo (Holland) ECC82

VR3

Unfortunately I am not that hardcore into tube world...

RCA Clear tops are some of the best tubes I have experienced by no small margin. That should be on your short list.

drumminman

RCA clear tops are far better than stock JJ Tesla (which were decent) that came with my Candela. The RCA's are not too expensive or uncommon at this point.

But the Amperex D-getter 7316's that I got from Greg blow both of them away. They're rare (and expensive) though. Brent Jessee has some for $600/pair!

Reputed to be very good also are 1955 CBS Hytrons JHY 5814WA, though I haven't heard them they're on my radar.

headrott

Brock, I have some Valvo (Holland) and possibly Hamburg 45 degree 12AU7's if interetsed. I would sell them pretty cheap as I have little/no use for them. I would need to listen to them as I haven't used them in a long time. They are good tubes.

I would highly suggest some Mullard long plate D-getter (from 1957 to 1959) tubes. They are smooth and detailed. Very nice. Also, I would suggest some Amperex 7316's. Some of the best 12AU7/varient tubes out there, period.

Greg

sda2mike

rca clear tops...and baldwins, not sure which tho..might even be relabelled rca's

heiney9

Greg, I'll keep that in mind if the deal goes through on the integrated amp because I'll need some 12AU7's right away.

Again, this is for a secondary rig, but it has enough power that I might on occasion swap it into the main rig. I know the Mullards and Amperex you mention are pretty much about the best and I know the $$$ relates to that. Normally I'd say that's too much $$$ for a secondary rig for tubes but I already have some pretty decent 12AX7's -- Valvo Hamburg ECC83 slant getter, Valvo Holland long plate D getter and some really nice 50's RCA 12AX7 long black plate sq getter.

headrott

heiney9 wrote: »

Greg, I'll keep that in mind if the deal goes through on the integrated amp because I'll need some 12AU7's right away.

Again, this is for a secondary rig, but it has enough power that I might on occasion swap it into the main rig. I know the Mullards and Amperex you mention are pretty much about the best and I know the $$$ relates to that. Normally I'd say that's too much $$$ for a secondary rig for tubes but I already have some pretty decent 12AX7's -- Valvo Hamburg ECC83 slant getter, Valvo Holland long plate D getter and some really nice 50's RCA 12AX7 long black plate sq getter.

Sounds good Brock. I hope the deal comes through for you. If you use the RCA black plate 12AX7's, I would use some "lively" 12AU7's as the black plates can be pretty laid back (IMO). The highs from the black plates can be somewhat rolled off, but they have absolutely outstanding midrange.

heiney9

I haven't found the RCA's that laid back, but I do have a lively office/computer room so perhaps that's why. But that's good to know and makes sense. A part of me is dreading having to find synergy between 2 different tube stages. I am used to obsessing over just one stage. I really need to NOT get carried away here and buy every kind of 12AU7. I have a tendancy to go ape **** and buy a couple dozen pairs of tubes to try :redface:

I should know next week for sure if the deal goes through.

H9

thsmith

H9, how many you need? I have some 5814s well maybe one I can send you that I have no plans to use.

heiney9

I will need a pair. I'll know by this time next week if I will have the amp. So let me know what you have.

Also looking for any experiences with the Chinese KT66 tube.

H9

thsmith

OK, I will look and see but I think I have one NOS but cant remember what it is.

organ

The RCA clear tops are not bad, but there are much better ones out there. 60's Mullard and 50's Tung-Sol are excellent. I also tried a pair of later Mullard (can't remember year but it had the new shield logo), and I like them as much as the early ones. Different sound but still very good.

But the best one I have is the Siemens triple mica 5814. I think it's from the 50's and they come in their original military tube containers. Very pricey, but worth every penny imo. I got a NOS pair 5 years ago for almost $200.

For new production, the JJ isn't bad at all. Sound characteristic is similar to that of early Mullard. There's also the Gold Lion re-issue that people are saying is better than many NOS.

Just becareful who you're buying your NOS tubes from. I prefer to buy NOS from reliable tube dealers. A lot of the NOS you find on ebay are bottom of the barrel scrapings. They may be NOS, but will usually have higher noise, poor section matching, etc. Most of the top grade stuff are almost gone.

For the KT66, I did have experience with them for a while. I only got to try two types. The Sovtek and the Saratov KT66. Both are very good, but I prefered the Sovtek. I found it more "lively" and dynamic.

Good luck on your hunt.

dkg999

RCA Clear Tops - I have some that are labeled Baldwin
CBS Hytrons - very smooth!
Sylvania Triple Mica blackplates JAN - you all liked the sound of the Rogue 66 Magnum pre - that's what is in it.

sda2mike

Re: organ's post.....that's very true: i have some jj's in my jolida int...they work really well

george daniel

RCA bp's.