Tube recommendations

[J Larsen]

I'd like to try some new tubes in my integrated stereo amp. I've picked up a few ideas from some of the dedicated audio forums, but thought I'd solicit opinions here as well.

My amp takes 4 KT88s for the power section and 2 12AX7s and 2 12AU7s for the pre section.

For the KT88s, I just tried the Gold Lion reissues from Russia, but am not happy with the bass definition (compared to the Prima Luna tubes I had in before). I really have no idea what to try next.

For the 12AX7s, I'm thinking about used Telefunkens or NOS Tungsrams.

For the 12AU7s, I'm thinking about used Telefunkens or NOS Mullards or Radiotechnique.

Any thoughts would be appreciated - also vendor recommendations would be great.

Thanks.

[jazzbo]

Well, those sound like good (and expensive) possibilities. I only have one unit in use that uses 12AU7 tubes, and one of my recent "tube rolling" adventures I bought a grab bag off ebay that has a few tubes each from GE, RCA and a few I can't identify. The RCA and the GE sound quite good. I've had Mullards too, from my 1959 EICO integrated stereo amp. If you don't need matched pairs, or even matched brands, there's almost always some bargains on ebay.

Can your amp also use EL34s? I'm pretty sold on the "Winged C" Svetlana tubes from Russia. And there's a modification for grid connection that seems to make a very significant difference (I've an amp I've known before and after this modification, and it was quite a change.)

The thing I've discovered over time is that I believe that tubes sound differently in different circuits and applications, and it's worth the time and effort to experiment and judge for yourself.

Edited January 21, 2011 by jazzbo

[porcy62]

My pre amp doesn't use the same tubes, but usually tubes have a "factory sound", expecially NOS.

Here you can find a good description of it, the seller is a nice and competent guy, I bought some tubes from him.

http://www.audiotubes.com/

One advise: you have to double check very very good bargains on ebay on the Nos like Telefunken CCA made in W. Germany, there are tons of fake chinese and russian tube with "telefunken" on the bottle.

About the price: NOS might be very expensive if you go for the most sought after Telefunken, Mullard, Amperex, but there are hundred of cheaper alternatives. I reccomend you to try them, TUBE ROLLING IS FUN.

Edited January 21, 2011 by porcy62

[J Larsen]

Well, those sound like good (and expensive) possibilities. I only have one unit in use that uses 12AU7 tubes, and one of my recent "tube rolling" adventures I bought a grab bag off ebay that has a few tubes each from GE, RCA and a few I can't identify. The RCA and the GE sound quite good. I've had Mullards too, from my 1959 EICO integrated stereo amp. If you don't need matched pairs, or even matched brands, there's almost always some bargains on ebay.

Can your amp also use EL34s? I'm pretty sold on the "Winged C" Svetlana tubes from Russia. And there's a modification for grid connection that seems to make a very significant difference (I've an amp I've known before and after this modification, and it was quite a change.)

The thing I've discovered over time is that I believe that tubes sound differently in different circuits and applications, and it's worth the time and effort to experiment and judge for yourself.

Thanks! I can use EL34s, though the manual says I'll lose a little power. (Given that my amp is loud enough for the neighbors to complain with the dial at 10 o'clock, I'm not too worried about that, though.)

What do you think of the Winged C KT88s? http://www.upscaleaudio.com/tubes/kt88/sed-kt88.html

My pre amp doesn't use the same tubes, but usually tubes have a "factory sound", expecially NOS.

Here you can find a good description of it, the seller is a nice and competent guy, I bought some tubes from him.

http://www.audiotubes.com/

One advise: you have to double check very very good bargains on ebay on the Nos like Telefunken CCA made in W. Germany, there are tons of fake chinese and russian tube with "telefunken" on the bottle.

About the price: NOS might be very expensive if you go for the most sought after Telefunken, Mullard, Amperex, but there are hundred of cheaper alternatives. I reccomend you to try them, TUBE ROLLING IS FUN.

Thanks, Porcy. I'm bidding on a pair of Telefunkens on ebay right now, but they seller has 100% positive feedback from nearly 1000 reviews (including lots of tubes), and they come with the original boxes, so hopefully they are legit.

I'm of the impression that NOS isn't as important for preamp tubes, because they draw so little power to start with so they have much longer lives. Do you agree with that?

I definitely plan on trying lots of different types, but I want to pace myself. I am, after all, standing at the top of a long, steep, slippery slope!

[jazzbo]

Have to say, I'm not that familiar with KT88s to begin with. I've amps that will run them, but they've been modded to favor EL34s and sound so good I don't run any other output types.

I think that input tubes can have a big impact to the overall sound of an amp, just as rectifier tubes can as well. I was surfing at top speed down that slippery tube rolling slope. I lost my reference points over time. I am in a 12A-type step program now.

Edited January 22, 2011 by jazzbo

[porcy62]

Thanks, Porcy. I'm bidding on a pair of Telefunkens on ebay right now, but they seller has 100% positive feedback from nearly 1000 reviews (including lots of tubes), and they come with the original boxes, so hopefully they are legit.

I'm of the impression that NOS isn't as important for preamp tubes, because they draw so little power to start with so they have much longer lives. Do you agree with that?

About the telefunken, you might check and follow the advise of the website I suggested. They show how to spot a fake NOS tube.

Tubes are important everywhere along the path of signal. My preamp use 2 6DJ8 (or 6922 and later equivalent) in the phono stage. I have the original Sovtek and the followin NOS: Siemens, Telefunken, Mullard and Amperex. Though I was pretty skeptikal about tube rolling, after a couple of tries I realized that every tube sounds different. It's like tunig a motorbike, fun and satifying. I am sure Jazzbo is with me on this.

Edited January 22, 2011 by porcy62

[jazzbo]

I'm not sure Jazzbo is. No I agree it can fun. In my case it can also be maddening. Doing it properly means waiting long hours for a tube to be totally warmed up before evaluating, and then you have memory issues of what the previous set up sounded like, listening for subtle differences, etc. Eventually for me it becomes a few steps further away from actually listening to and enjoying music. So. . . I've stuck with the suggested tubes from the manufacturer for the most part. And get great sound. I rolled tubes heavily for a few years, and now I rarely swap out tubes, I've found a handful that seem to work really well and have some distinct signatures, and I'll change a tube if I want to have that signature to complement a number of recordings.

[sidewinder]

Just got a new pre-amp on demo today (non-tube). The results are astonishing !

[porcy62]

Just got a new pre-amp on demo today (non-tube). The results are astonishing !

Ah!

I still got my old pre-amp, plus some other stuff (interconnects and power cables), in the hi-fi shop, nobody bought them until now, I guess I will have to trade them back to the dealer, admittedly a "friend", with my loudspeakers for new loudspeakers, obviously it will cost me a lot of money, but, apparently, it's the only way to cash my old stuff.

p.s. I guess it's a Naim

Edited January 22, 2011 by porcy62

[sidewinder]

p.s. I guess it's a Naim

How did you guess?

Yep, a nice 'Olive' NAC 52. I now need to re-listen to my whole collection.

Edited January 23, 2011 by sidewinder