SDS, Supra, MPX tuberolling, the new global, improved thread - Page 29

Thought I'd take this opportunity to make my first post in the mighty SP tube rolling thread. I haven't read through all of it yet, but I'm continuing to page through it, read, and learn.

Currently I'm running a Ken Rad 6sn7 and RCA 5687s.




I'm really enjoying the warmth of this setup. Its crazy how when I got into this hobby I thought I would be a guy who loved neutrality and an analytical sound. Now I want color, depth, instrument separation, and warmth.

Also I thought that second picture turned out cool, you can see a blurry DAC in the background and me taking the picture on the shiny top of the tube. I think I'm handling the tubes well, making sure to grip them at their metal bases whenever possible, and if I do touch the glass I wipe it down gently with a MB cloth I use to dust my fountain pens.

I'm listening to Roxy Music's "Avalon", and I'm loving being able to have this warm sound, but nice punchy drums and meaty bass lines. Strangely, I'm also finding myself more comfortable listening to music at lower volumes then I did with my SS.

Great combo JJ .... one of the best.

I have also always believed you can listen at lower volumes with tubes because the sound has fullness. SS can sound to thin and you reach for the volume control trying to add body to the sound .... that you usually dont get.

I am glad to hear the amp worked out so well for you.

"I'm really enjoying the warmth of this setup. Its crazy how when I got into this hobby I thought I would be a guy who loved neutrality and an analytical sound. Now I want color, depth, instrument separation, and warmth."

Neutrality is often over rated!

- augustwest

Earlier in this thread I gave high praise for the 5965 tube in the driver position (see post #263), especially with the Grado headphones. This evening I have found a tube that surpasses my glowing review of the 5965 tube. It is a tube that has not received much notice here. It is the 12az7 tube, the one I tested was manufactured by Raytheon. Like many of the other 9 pin miniature tubes it makes use of the ECC tube adapter #1 in the SinglePower amps. With the 12az7 in the driver position I made use of the 6bl7’s as output tubes. The 6bl7’s were run at the 400 volt setting.

What sets the 12az7 apart, like the 6414 tube, from many of the other 9 pin miniature tubes is its ability to work equally well with the Sennheiser and the Grado headphones. Many of the 9 pin tubes are satisfactory with the Sennheisers and are thin and brittle with the Grados. The 12az7 has a robust mid range and bottom end, with a tonal palette that puts it in direct competition with the upper tier of 6sn7 tubes.

I started the evening testing this tube with the Grado PS1's and my usual half dozen CD’s that run the gamut from Diana Krall, to the band “X”. After sampling three or four of these I knew I was on to something special, so I put in a CD that has proved to be a hard case for most driver tubes with the Grado headphones, “Miles Ahead”, by Miles Davis / Gil Evans. This version of this CD is the re-mastered one by Phil Schaaps. Even so the treble can often prove to be a challenge for many tube sets in combination with the Grados. In this instance the 12az7 handled the treble without restricting the bite of the brass of Davis’s horn, but at the same time keeping it in check and not letting it become sharp and piercing as is so often the case. One note of caution, however, the 12az7 has a rather high amplification factor, so there is limited volume adjustment room with the Grados and it helps to have variable output on your CD player, although if you don’t it is still likely workable.

After this trial I went to the Senn hd 600’s and found this tube was also outstanding with orchestral and string quintets. Using Bernstein’s Mahler Symphony #1, the Brahms String Quintets and the Brahms Cello Sonatas featuring; Rostropovich / Serkin as test disc’s. This tube combination was so successful that it eliminated any thoughts of a Sennheiser veil and with the Sennheisers headphones there is no problem with restricted volume adjustment. . . . . . My next step is to try the 12az7 with other output tubes.

Happy listening!

- augustwest

Dave, do you have a lower output source? I cant use the 12bz7 or I hear hum with the sound muted. The tube gives to much gain with my sacdmods players .... and my E5 too.

"Dave, do you have a lower output source? I cant use the 12bz7 or I hear hum with the sound muted. The tube gives to much gain with my sacdmods players .... and my E5 too."

I'm just using a rather standard Sony CD player, that has variable output, with my MPX. I'm not having any kind of hum problems at all, in fact it is dead silent.

With the Sennheisers I have the volume at the 9 - 10 o'clock position and with the Grados about the 7 - 8 o'clock position. I then use the variable output for fine tuning the volume.

- augustwest

My source must be even hotter than I thought.

I've also been able to use the 12at7 and 5751 tubes with success too, although they also are pushing the edge of envelope in terms of having too high of an amplification factor. Thus far un-wanted noise has not been a factor.

Although, I've avoided giving the 12ax7 a try, figuring that might be too much of a good thing and pushing things too far.

- augustwest

High gain driver tubes

With my MPX3 SLAM SE, the 5751 with a mu=70, only works with 5687. It is noisy driving 6SN7s (at low power) and 6BL7GTAs at high power. I have only used these 3 tubes as outputs. Too bad, it sounds better than anything else i have tried (7N7, 6414, 7062, 5965, 12AV7, 12U7, 12AT7) with the 5687s.

New tube alert for the Extreme/ Extreme Platinum amps. We now can use the following output tubes: 6as7/5998/6080/6520/7236 .... and the 2399 and 7802 if you can find them. Some amps designed specifically to provide the extra heater current and to dissipate and tolerate much higher internal temperatures can use the 6336 and 6528. I set my first Extreme up to use these tubes but I still think the amp runs to hot with the 6336/6528 in the Extremes little chassis. I would only use these tubes in an Extreme type circuit with a ruggedized seperate power supply .... or with a much larger single chassis including a beefed up parts package with 25 amp diodes etc...

So far, I like the Sylvania 6sn7/7n7 for gain with the Tung Sol 5998's in the Extreme Platinum; this combo is extremely open, detailed and refined but with good speed and snappy dynamics. But I suspect I will switch to the 2c51 in the Platinum amp once I get my second 2c51 adapter .... for some experimentation. I especially like the Tung Sol 2c51 with Bendix 6080wb's in the stock Extreme or the GE grayplate 6414 with the inexpensive Raytheon 6080wa's in "The Beast".

The 6as7/6080 series of tubes are the most powerful tubes I have had in these amps and the bass power and bass density are soooo evident; especially in "The Beast". I am pretty much convinced these output tubes throw a larger soundstage vs the other 5687/6bl7gt/6bx7gt output tubes, using the same gain tubes, but the 6bx7gt's at high voltage are very close.

I talked to Mikhail for a short chat about my new Supra XLR Extreme. Mikhail said he didn't think I would ever change to the 6BL7GTs because he likes the high output tubes that much better. He also said again the soundstage is the widest he has ever experinced with an headphone amp.

Keep up the research Earl!

Earl Do you know what tubes he is using in my amp?

I cant stop so you are in luck!

No idea .... as a guess .... some Rayhteon 6080wb's or some tung Sol 5998's.

Hey guys, a request for a little advice. I want to try these Tung Sol 5687's d-getters I hear so much about. First, when I google Tung Sol and 5687 it took me to Tube Depot:

http://www.tubedepot.com/nos-5687-ts.html

Now, they say the tubes are marked United, but they are definitely tung sol. Can I trust this? I have heard Tube Depot mentioned around here, so I am assuming they are a reputable dealer that knows their tubes.

Second, there are several "testing" options in the drop down menu there. Standard Test, High Gain, Matching, Balanced Triodes, Matched + Balanced Triodes, Low Noise + Microphonics. Any of those I should go for? And perhaps a brief explanation of each?

Thanks for the help.

If i am correct then that is what you would call rebranded tubes.My 5687's were not labeled tung-sol but something else instead so i don't thing you should worry about that.

How much are they charging for all those tests?Also from my understanding microphonics are not something that happens in the 5687 at least i have never heared of one.Go for the Matched test to get a pair likely to be equal to each other.

The tests start at $2.00 but with almost all options, it looks like it would add $8.00 to the cost of each tube. In my experience, the 5687 can be microphonic but it cleared up by re-seating or wiggling the tube.

Happy Listening!