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12bh7 for a 12au7 - Page 2

post #16 of 37
Thread Starter 
I may have to change my name to tubejunkie. Help!
post #17 of 37
Luckily this addiction is generally good for you, not your relationships but THAT is an entirely different saga. My favorite tube has to be the 6BQ5 - simply because it was the first tube amp I owned and just love the way it does vocals. I stumbled on this over the holidays and it is ever so tempting, might not be the best sounding amp but it would fill a void in my headphone amps
http://www.tubecad.com/2006/11/blog0086.htm . but getting off topic and not getting much work done ..dB

ps Tomb, thanks for the great link to Tube Depot
post #18 of 37
Thanks for your link as well, dBel. I love tubes, but I'm still a babe in the woods holding onto my insulator blanket. That 510V scares the *&$%#^ out of me.
post #19 of 37
I still recall the tremor in my hand when I first probed 350V (one hand in pocket like a good lad)..dB
post #20 of 37
I just started rolling tubes in my SOHA and damn is this addicting! I have a couple of the recommended JJ's, which I thought were very good until I started rolling. I picked up some 5963 RCAs, a GE and a couple Sylvania's off ebay real cheap. I haven't spent much time with them but here is my initial reaction.The Sylvanias are not good at all, the top 1/3 of the spectrum sounds like crap. The GE GP sounds good and has nice low end, but maybe a bit boomy. The RCA GP is probably my favorite so far, but I have a couple RCA BPs I still need to get some time with.

Anyway, happy rolling!
post #21 of 37
Thread Starter 
I let an German rft burn in all night and yesterday when I listened to some john mayer (gravity) I was surprised at what I heard. The sustain on the cymbals seemd to go on and on. I have never heard this before on any system. I think I may be in love with this tube. It has made me burnin my cleartop and I still have to see how that sounds.
post #22 of 37
I have heard that the German tubes are really good. Some vendors say the Telefunken 12AU7 is the best in the world. Not being able to afford them, I probably will never have the chance to confirm that.

Admittedly, I am a GE fan.

Still stuck on the GE 5963, to me it's really a sterling tube with great detail, ample bass, and an uncanny soundstage. At $4 most places, it's a great option for the SOHA and in keeping with its original premise of Stoopidly simple and cheap.

You guys are probably noticing that deep and powerful bass is not an issue with any tube in this thing. Instead, what separates the good from the run-of-the-mill is detail and luscious highs.

There's another tube that qualifies immensely in that regard: the GE 6680. It's definitely in that vein that HJ mentions of "... cymbals seemed to go on and on." Originally designed for mobile radios (walkie-talkies?), it supposedly is tolerant of varying voltage on the heater supply. I can't make a connection with how that would help its performance in the SOHA (regulated heater supply). However, it does! An additional benefit is that the amplification appears to be a little less potent - perhaps 3/4's of the typical 12AU7. So that helps if you're on the edge with low impedance phones or you jumper the output resistors.

It's a little rare, but not too bad in cost at about $7 - $12 most places.
post #23 of 37
Thread Starter 
I don't know, but if thet rft turns out to be my best tube I will probably get a bugle boy and a siemens. I suppose 20 or 30 a tube is not too ridiculous.
post #24 of 37
Quote:
Originally Posted by sacd lover View Post
I personally like the 12bh7 better than all the 12au7's I have tried. There are some good 12au7/5814a's like the early 1950's Raytheon and Hytron D getter, 2 mica tubes. But the 12bh7 is more neutral, dynamic and resolving in my amps. The 12bh7 should work fine as long as the amp can handle the additional heater current draw of the 12bh7 tube.
Hehe, you just let me know if you ever want to unload all those crappy 12au7's. :P

Biggie.
post #25 of 37
Makes tube rolling such big differences in sound ?
I didn't have chance to try it, I built my soha only with gold pin JJ tube (I am from Slovakia, where JJ tubes tubes produces) and it sounds very good.
Which tube should I try in your opinion ? With which tube should I expect biggest difference ?
post #26 of 37
Anyone know if the Raptor can handle having a 12BH7 instead of the 12AU7 in the gain stage? Would it make much difference in the Raptor?
post #27 of 37
Thread Starter 
I noticed a nice warmth and airiness with an German RFT.
post #28 of 37
Quote:
Originally Posted by ferencvaros View Post
Makes tube rolling such big differences in sound ?
I didn't have chance to try it, I built my soha only with gold pin JJ tube (I am from Slovakia, where JJ tubes tubes produces) and it sounds very good.
Which tube should I try in your opinion ? With which tube should I expect biggest difference ?
IMHO, the GE 5963 is far above the other tubes that you might put in the SOHA. The GE almost acts like a transistor - very, very tight - with no "backlash." That gives it an outstanding imaging, like a three-dimensional effect. The frequency response is quite sweet as well: lots of clear highs. It is also the one tube I've tried - out of 14 different types of 12AU7's - that seems to have a bit lower gain than the rest. You can actually adjust the volume a littl more than an off and on in 1/4 turn. I have tried several GE 5963's and some will vary slightly on the high end, but in general, the performance is consistent.

Some others to try that may be better than the JJ (IMHO):
GE 6680
Outstanding frequency response, better than the GE 5963, but without some of the outstanding imaging. This tube has perhaps the sweetest highs with a typical "liquid" performance - as opposed to the transistor tightness of the 5963. It also exhibits slightly less gain than the typical 12AU7, but is not as tame as the 5963. Note that this tube is somewhat rare, but affordable for reasonable prices at some places ($10-$16). This is unlike the 7316, which is quite rare and one that I cannot afford to try on a whim.

Raytheon CK5814A
This one is pressing the 6680 hard. It has perhaps the best construction of the NOS 5814's and 6189's - robust upgrades from the typical 12AU7. The highs are almost as outstanding as the the GE 6680, but with all the power of a typical 12AU7. You can't go wrong with this tube.

Sylvania Gold 5814A
TungSol 5814A

Both of these are very close to the Raytheon. I would rank them slightly less.

BTW, I have both GE "5 Star" and RCA "Command" (black plates) 5814A's (and some JAN's) - they do not sound up to the standard of the three 5814's listed above. I keep changing my opinion on the RCA "Command" - next week I may like it again. The GE 5814A - afraid not. It has given no indication of performing as well as the others - tried two of them, too.

EI 12AU7 Gold
This has the best response of new production tubes, IMHO - better than the JJ and the EH below. I have read reports that the regular version of the EI tube is not stellar. I would never credit gold pins to making a sonic difference, but perhaps they took greater care elsewhere, too. It's a very nice tube.

ElectroHarmonix 12AU7
I am currently having a love/hate relationship with this tube. I keep giving it more time, but with contradictory results. It sounds outstanding on some headphones - with piercing, metal highs. It also sounds positively awful on my HD580's. In either case, it possess huge POWER, especially bass - almost overwhelming on some phones (to me, that's good!). It has very high-quality construction, and is much fatter (larger circumference) than any other 12AU7 I've seen.

One final note - if you are using a pair of Sennheiser HD580/600/650's, you should try jumpering the output resistors. The sound impact and dynamics will improve greatly. Keep in mind that will make it almost uncontrollable with low-impedance phones, however.

P.S. If it follows form, your gold-pin JJ may be much better than the plain JJ I have. I think that is the same case with the EI.
post #29 of 37
Thread Starter 
On your last statement tomb. I have noticed yesterday that the hd580's I just picked up do not sound as good with the 150 ohm resistors with respect to my 225 grados. The grados seem to show the nuances of tube rolling more. I need to install jumpers and see what happens.
post #30 of 37
Quote:
Originally Posted by headphonejunkie View Post
On your last statement tomb. I have noticed yesterday that the hd580's I just picked up do not sound as good with the 150 ohm resistors with respect to my 225 grados. The grados seem to show the nuances of tube rolling more. I need to install jumpers and see what happens.
By all means, HJ - the 150 ohm resistors are only intended for low-impedance Grado's. They will make your Senn's choke.

After all, it's presenting a 450 ohm load to that little opamp.
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