Tubes Asylum Questions about tubes and gear that glows. FAQ

---

[ Follow Ups ] Thread: [ Display  All  Email ] [ Tubes Asylum ]

---

[ Alert Moderator ]

---

Suggerimenti per vario 12AU7

Posted by Bambi B (A) on February 14, 2007 at 08:27:44

In Reply to: 12AU7 as a buffer - suggestion of brand/model. posted by beppe61 on February 13, 2007 at 23:42:41:

beppe61,

I don't know the particulars of the circuit and which tubes are suitable, but it is probably best to use a 12AU7 or plug in variant. the 12AU7 can have a number of designations according to certain parameters of noise and ruggedness:

12AU7= ECC82, E82CC, 5814A, 6189, 7316

- there is also the 5963 which may or not be suitable as it's electrically a bit different. Personally, I would wait for some experience before going off to the marginal types.

In your preamp, I don't know what qualities the tube should have sonically, but my thought is to try perhaps three good, tested NOS examples. I tend to like the tougher models like these 12AU7s:

> Siemens and Halske triple mica 5814A > a very lively, detailed, punchy one, solid bass. This is my favourite 12AU7
> CBS black plate, stirrup getter 5814A > extremely refined, smooth, and a nice clear bass
> Amperex/Philips/Valvo E82CC > very nicely balanced
> RCA "Command" 5814A > good all round sound
> Philips/Amperex/Valvo 7316 > quite amazingly good- and even more amazingly expensive if the early long plate version!
> Philips/Amperex/Valvo ECC82 > really the standard Philips made ECC82 from the early to late 60's is just fine all round. I'm not sure the extra cost when it's labeleled Amperex "Bugle Boy" is necessary.

You may see recommendation for the RCA "cleartop" 12AU7. This is a lively one that's very good in sleepy vintage gear, but may be a bit bright in a modern preamp.

The "Philips/Amperex/Valvo" is because the Philips company produced the same tube- same design and tooling in various factories and labelled them several ways- confusing. Fortunately, thePhilps tubes have little codes etched in the glass that tell where and when the tube was made. If you shop for anything Amperex/Philips you might get used to these codes and varify them. I recently bought a Valvo 6189 that was said to be from the Philips, Hamburg factory which turned out to have a code from LaRadiotechnique in France. The relabelling of tubes is very complex and it's important to know what you're listening to!

This is a little confusing as the various models have subtle differences in construction and the tubes of the same maker and model can sound different when made at a different time.

The 12AU7 for some reason has become expensive lately, but as you are using only one, you might try three or four and resell the ones that didn't please you. If you are not experienced with buying NOS, you may want to contact a dealer that likes to chat and buy tubes that are really well tested. The price may seem substantially more, but in reality, you will spend less by having tubes that are know to be good. It's possible on Ebay to spend a lot of time and money on tubes that are noisy or defective, though there are a couple of reliable sellers on German Ebay. I'm not sure, but there may be dealers that would allow you to try and return the unwanted ones- perhaps with a restocking fee. You may want to contact our friends Jim McShane and Kevin Deal for recommendations and ask about a return policy of some kind.

Scriva prego ancora e dicaci che cosa.

Cheers,

Bambi B

This post is made possible by the generous support of people like you and our sponsors:

Sonic Craft

---

[ Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]

---

[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]

---