Now I get what retubing is about...

[StevenSurprenant]

There doesn't seem to be much interest in this subject, but I'll give it one last try.

I installed my newest tubes, Svetlana Winged "C" SED EL34, in the amp and the results were astounding. The whole ordeal of tube rolling was not what I expected, mainly because most posts talk about tubes changing the tone. That, a person could do with an EQ. It went way beyond that.

First off, my Yaqin came with Shuguang tubes, 12ax7's and 12au7's in the preamp section and EL34B's for the power. These sounded very nice and this amp bettered my previous amp in every way. The difference wasn't huge, but enough that I won't be going back to my old amp any time soon, or ever.

The first tubes I changed were the preamp tubes with Tung-Sol's. At first these new tubes sounded very warm and dark, but at the same time detail/resolution improved across the board. The bass was warm, which is how I would think, tube like, would be described. It was very pleasant, but not exactly what I would call accurate. After a time, this warmth, in the lower registers, completely went away. Detail and resolution continued to increase. After full burn in, the soundstage was very clear and I could easily hear everything regardless of the level it was recorded at. In addition, there was more detail (resolution) of the different instruments and the space between them. On the down side, the bass was lacking in many recordings and the recordings sounded thin. On the upside, all of the poor recordings I had sounded better. A few that I classify as ear bleeders became less so. My good recordings sounded wonderful, albeit with less bass.

I then installed the Svetlana EL34 tubes. At first, the highs and lows improved considerably, but voices, which had previously been the best part of the audio presentation, seemed to become flattened into the soundstage and sounded muddy. I was scared it would stay that way, but as I listened, voices seemed to return to their former glory and even exceeded what I previously heard. After full burn in, resolution achieved even greater heights, but dynamics made a huge leap for the better. In addition, the harmonic content of the instruments increased. Bass was very tight and the lower midrange and upper midrange seemed to sound fuller which added to the solidity of the images. One side effect of all this is that, previously I would be listening to the main performer, who would stand out in the mix, and all the instrumentation was less prominent, but now, everything stood out and became prominent in it's own right, but never distracted from the main performer. I couldn't believe what I was hearing. There was so much going on that I never realized before. It changed the mundane into something exciting.

In any case, the Tong-Sol's and the Svetlana's were a good match for each other in this Yaqin amp.

Out of curiosity, I reinstalled the Shuguang 12ax7 preamp tubes and I freaked. I couldn't get them back out of the amp fast enough. Bass, mostly mid bass, increased causing everything to sound muddy and the soundstage collapsed. It was at this point that I now understood the synergy that tubes shared. To me, it was a revelation. It also explained why there were so many different opinions about tube brands.

Together, the Shuguang tubes worked very well together, their strengths and weakness added together created a balanced sound, as did the Tung-Sol's and Svetlana's.

This explains the results I got when using Tung-Sol's (in the preamp section) with the Shuguang EL34 power tubes. As I mentioned, there was a substantial increase in clarity/resolution but a loss of mid bass with this configuration. If I were to reverse this description, it would accurately describe the Shuguang 12ax7'c sound quality when used with the Svetlana EL34.

In the end, this "tube rolling" has far exceeded my expectations and what I've learned goes far beyond which tubes are better. It has taught me that it's about synergy or "ying yang".

[Hyfi]

Steve,

I am interested in your results and thoughts. I don't "roll" but have retubed both my pre and amp with way better tubes than I originally had used and what came with them. Since I like to run my Pre in Buffered Passive mode, the 12ax7 is taken out of the path and only the 12au7s are used. I am considering a few new (old) ones for that spot. The early '60s 6FQ7s RCA Cleartops I dropped in my Counterpoint made worlds of difference.

[StevenSurprenant]

Steve,

I am interested in your results and thoughts. I don't "roll" but have retubed both my pre and amp with way better tubes than I originally had used and what came with them. Since I like to run my Pre in Buffered Passive mode, the 12ax7 is taken out of the path and only the 12au7s are used. I am considering a few new (old) ones for that spot. The early '60s 6FQ7s RCA Cleartops I dropped in my Counterpoint made worlds of difference.

Thanks Hyfi.

I'm still mostly ignorant about tubes and tube amps. Please correct me if I make any mistakes....

In any case, I do realize (now) what impact different tubes can have on sound quality, especially clarity, soundstaging, dynamics, and tone.

I was just thinking...

I'm having trouble wrapping my mind around the idea that NOS tubes are better than new production tubes. I'm inclined to think it's a fad and nothing more, but so many people claim that NOS is better. My mind is still open on this. Anyone have any thoughts on this?