[triod750]

Matching tubes is imperative in order to enjoy the music. I am now listening to Litania, music of Krzyzstof Komeda, performed by Tomasz Stanko Septet. Output tubes are Melz 6N12S and input tubes are perfectly matched Philips 6J5GT, made in USA and National Union 6C5GT, also made in USA. Can't get any better. Both made in USA, hence a perfect match. And the music is very enjoyable.

 

[Isaacc7]

A while back I had asked if Sylvania ever made a round plate 6/12sn7 to match the round plate 6/12j5gt they made. I still haven't found any of those but I have found the 12ah7gt! It is a round plate tube that seems to be similar to the 6sn7 but with a different pin out. Apparently there was a 6ah7 but they are relatively rare. The 12ah7gt is super cheap, I might pick some of them up from various manufacturers and see what they have to offer. Will also post this in the 6sn7 thread too to see if anyone there has any insights.

 

[gibosi]

A while back I had asked if Sylvania ever made a round plate 6/12sn7 to match the round plate 6/12j5gt they made. I still haven't found any of those but I have found the 12ah7gt! It is a round plate tube that seems to be similar to the 6sn7 but with a different pin out. Apparently there was a 6ah7 but they are relatively rare. The 12ah7gt is super cheap, I might pick some of them up from various manufacturers and see what they have to offer. Will also post this in the 6sn7 thread too to see if anyone there has any insights.

The 12ah7 and 6ah7 are fairly similar to a 12au7. And there are loctal versions, 7AF7 and 14AF7. I've had good luck with these and IMHO they are good sounding tubes.
Oh, I have never seen a round plate Sylvania 6/12SN7. I am pretty sure it was never made.

 

[bcowen]

The 12ah7 and 6ah7 are fairly similar to a 12au7. And there are loctal versions, 7AF7 and 14AF7. I've had good luck with these and IMHO they are good sounding tubes.
Oh, I have never seen a round plate Sylvania 6/12SN7. I am pretty sure it was never made.

I have a few 7AF7's. The lower gain (versus a 6SN7 / 7N7) is barely noticeable, if at all. I still prefer the Sylvania tall bottle 7N7, but the 7AF7's are quite nice themselves.

(note that the GE was made by Sylvania...I haven't totally lost it )

 

[Isaacc7]

The 12ah7 and 6ah7 are fairly similar to a 12au7. And there are loctal versions, 7AF7 and 14AF7. I've had good luck with these and IMHO they are good sounding tubes.
Oh, I have never seen a round plate Sylvania 6/12SN7. I am pretty sure it was never made.

I also don't think Sylvania made a round plate sn7 tube. Too bad, the 12j5gt tubes I have are really nice. All of the 14af7 tubes were made by Sylvania, were the 12ah7 all made by sylvania too? Are the 7af7 and 6ah7 really the same tube? I went over the data sheets quickly and I thought there were some differences. Maybe the published specs by different companies were written differently?

 

[gibosi]

Yes, there are some small differences. In fact, the 7AF7 is considered to be a successor to the 6AH7GT. However, I couldn't hear any difference between a 12AH7GT and the 14AF7 in my Glenn. So to my mind they are close enough to be considered the same. But of course, YMMV.

 

[OldSkool]

Finally found a nice pair of NOS GEC L63 for my ToolShed preamp.

Up to now I have been using Brimar or Visseaux 6J5g's in this preamp, but these GEC's are giving me more detail...nice! However, the upper treble is more pronounced. Is that something that a few hours burn-in will tame or is that just the GEC house sound?

Cheers, JC

 

[gibosi]

Finally found a nice pair of NOS GEC L63 for my ToolShed preamp.

Up to now I have been using Brimar or Visseaux 6J5g's in this preamp, but these GEC's are giving me more detail...nice! However, the upper treble is more pronounced. Is that something that a few hours burn-in will tame or is that just the GEC house sound?

Cheers, JC

In my experience, the GEC house sound is indeed characterized by more treble emphasis and air. And I hear this with GEC rectifiers, out-put tubes and drivers.

 

[leftside]

Finally found a nice pair of NOS GEC L63 for my ToolShed preamp.

Up to now I have been using Brimar or Visseaux 6J5g's in this preamp, but these GEC's are giving me more detail...nice! However, the upper treble is more pronounced. Is that something that a few hours burn-in will tame or is that just the GEC house sound?

Cheers, JC

Ah someone else mentioning what I hear with the GEC tubes - the detail. They seem to extract that last drop of detail for me. But, I don't find the upper treble too pronounced. Give them a bit more time.

 

[gibosi]

Everyone has different ears and gear. And for me, too much GEC, and especially too much Telefunken, is just too much upper treble. My go-to test is Norah Jones. To my ears, there is a slightly raspy quality in her voice. And in some recordings that raspyness can be "uncomfortable" to listen to. Just this evening, I pulled out a GEC rectifier and installed a Holland-made Philips rectifier instead. Easier on my ears. But again, my ears and my gear. YMMV.

 

[pravous]

More adaptor shenanigans. Tonight Ken Rad 7193. Top connections are for the plate and grid. Only have an hour or so on them but so far very impressed. Expansive soundstage of a Sylvania combined with the bottom end Ken Rads are known for.

 

[CAJames]

More adaptor shenanigans. Tonight Ken Rad 7193. Top connections are for the plate and grid. Only have an hour or so on them but so far very impressed. Expansive soundstage of a Sylvania combined with the bottom end Ken Rads are known for...

Cool. I've always been a little #7193curious, but I'd need 4 of them and am a little afraid of interference with that many top connections. But I haven't spent nearly enough money on tubes lately so it might be time to try it out.

 

[pravous]

Cool. I've always been a little #7193curious, but I'd need 4 of them and am a little afraid of interference with that many top connections. But I haven't spent nearly enough money on tubes lately so it might be time to try it out.

I am only using 2 of them in place of 6j5 but they are dead quiet. None of the noise issues that occur with type 37 and some type 76. Might be new toy syndrome but absolutely loving the Ken Rad 7193. There is a great post about this family in the Bottlehead crack tube rolling thread. (Post 9737 by Tom-s). One of the more interesting variations is the Hytron E1148 which has horizontal instead of vertical construction. Some pretty interesting Gec/Marconi under the CV6 designation as well.

 

[Marutks]

Do you like this tube?

 

[maxpudding]

Do you like this tube?

All of my 6J5MGs are the tall silver versions, made by Mazda or Visseaux. I like them very much. I think a couple of members here have some experience with this short version of the 6J5MG.