Good Singlepower tube combination for MPX3 and Supra

[Frihed89]

I very much like the "truth" of the K-701s and I also love the smooth sound of WWII era 6SN7GT tubes as outputs in my SP MPX3 Slam SE. So, I have needed to find hi-gain input tubes. The 12AV7 family of tubes work pretty well as inputs, but they lack the gain to drive the 701s really well, I think. So, in my experimentation I have gone up as high 5751s with good success, but recently settled on the 12AT7WA (Brimar, Sylvania, and Raytheon) as an input with Raytheon 6SN7GT flat black plates, NU Grey Glass, and Sylvania Bad Boys as outputs.

Try this tube as an input with the 6SN7GTS. The various models all sound very different, but this combo sounds very good with K-701s. You can also use 5687s, but you lose the smoothness of the 6SN7 and the 12AT7 adds some Slam to the flavour.

Got to take my pills. Bye.

[tom_hankins]

Try KenRad VT-231 Black glass in front of either a pr. of Sylvania VT-231s or the Bad Boys.

Or the TungSol roundplate in front of either pairing of the Sylvanias.

[purk]

Have you tried the Sylvania 6BL7GTs/GTAs as output tubes? The idea of getting the "SE" option is to run 6BL7/6BX7 tubes. You can also try Tungsol 2c51 (need the adapter), or Tungsol Roundplate (Expensive), or Kenrad VT231 as a driver tube.

[Guest sacd lover]

I very much like the "truth" of the K-701s and I also love the smooth sound of WWII era 6SN7GT tubes as outputs in my SP MPX3 Slam SE. So, I have needed to find hi-gain input tubes. The 12AV7 family of tubes work pretty well as inputs, but they lack the gain to drive the 701s really well, I think. So, in my experimentation I have gone up as high 5751s with good success, but recently settled on the 12AT7WA (Brimar, Sylvania, and Raytheon) as an input with Raytheon 6SN7GT flat black plates, NU Grey Glass, and Sylvania Bad Boys as outputs.

Try this tube as an input with the 6SN7GTS. The various models all sound very different, but this combo sounds very good with K-701s. You can also use 5687s, but you lose the smoothness of the 6SN7 and the 12AT7 adds some Slam to the flavour.

Got to take my pills. Bye.

You dont need higher gain to drive 701's ... you need more current. That comes from using the higher current output tubes like the 5687 or 6bl7gta. I can clip the 701's using the older gain tubes and 6/12sn7's with a mu of 20 or so. All the higher gain input tubes get you is a higher noise floor = more noise

[luvdunhill]

For output, I'd try the side getter RCA 6BL7GTA or (even better) the older CBS/Hytron 6BL7GT (non-A) tubes. For input, Tung-Sol 5670 or (even better) Ericsson 396A if you have the adapter needed for these two or pinched waist Amperex 7062. These combinations sound awesome on all headphones to me. I like detail and things a bit on the bright / hot side.

edit: I thought you were looking for a recommendation Sorry, ignore the above as it looks like you have a combination that sounds great with your setup! enjoy!

[Frihed89]

Thanks for all the replies. I have been at this tube rolling thing for about a year, now. I have no electronics background (which would help me a lot) so I do everything by ear. Unfortunately I was virtually totally deaf in one ear until I had an operation in May that restored quite a bit of my hearing. I have metal prosthesis (es) in both middle ears that have a tendency to make things sound bright and edgy (like the 5687 tube).

The RCA, GE, Sylvania, Tungsol, and Raytheon 6BL7GTAs are too warm for me. I really don't use the high power option any more.

I like the Pinched waist amperex 7062 to drive various 6SN7GTs or the pinched waist amperex 7119. I do use the 5687/7119s as outputs, but find many makes/types of these tubes to be a bit bright and edgy in my sick ears.

It may not be the gain of the 12AT7WAs or 5751s that drive the 701s to much higher levels, but these tubes really do drive the 701s very well. I think it's Ohms law at work inside the tube!

I have a large collection of WWII era 6SN7GTS (but no Tuungsol round plates). But I generally do not use 3-in-a-row any more because they can't drive the 701s that well. (Except for the older 100Ohm+ HD 595, I haven't found a high impedance headphone I like).

Thanks again.

[Frihed89]

if you haven't tried the gold pin sylvania 5687s, i would suggest it. they have most of the good qualities of the Tung-Sol D-getter, but is warmer (without being overly warm, to my ears).

Thanks. I have NOT heard this tube, but all of the 5687s i have are a little too much in my face and sound "edgy" and bright as well (an artifact of my operation, I think). That makes them fatiguing for me.

I always appreciate suggestions for new tubes to try in my SP. Thanks again.

[tkam]

Have you tried a very warm tube like the RCA 6sn7's driving a pair of 5687s?

[Frihed89]

Yes, and actually the ones that do the best to produce a non-fatiguing sound (to me) are the "bad boy", the Raytheon and NU VT-231s, but the RCA's do do this, too.

I don't listen to a lot of music that sounds good with Slam. Ok, Ted Leo, Arcade Fire, peppy stuff - that doesn't sound that bad on the 5687s, but I can't listen to these bands for very long anyway.

I was lucky enough to go to an Arcade Fire Concert recently in Copenhagen. That was something!

[luvdunhill]

The RCA, GE, Sylvania, Tungsol, and Raytheon 6BL7GTAs are too warm for me. I really don't use the high power option any more.

If this is the case, the 6BX7-series of tubes on the high-power setting is calling your name. If even after listening to these (they're cheap, so pick up a pair) *then* perhaps the high-voltage setting isn't for you Or maybe a trio of '51 Hytrons

My MPX3 has a not-so-high voltage setting on it and it sounds wonderful with the 6BL7GT which on my other MPX3 SE with the standard high voltage setting sounded dark and surripy. I'd still look for a pair, as they're hard to find these days and worth trying (and hoarding).

I could never get the 7062 driving the 7119s to really work... it sounded like something was broken, so I quickly removed them

In addition to tkams idea, I'd try the 12bh7 (RCA or Brimar) driving a pair of Sylvania 5687s...

[nsuttitinagul]

Try KenRad VT-231 Black glass in front of either a pr. of Sylvania VT-231s or the Bad Boys.

Or the TungSol roundplate in front of either pairing of the Sylvanias.

I'm only running on some EH Gold 6SN7s for output, but I found the KenRad VT-231 a bit too warm and slow for my tastes when paired as such.

I'm using a Muntz TV 6SN7GTA as the input tube. I'm wondering if these tubes might have been relabeled or something because I can't find any information on them online.

[PFKMan23]

Muntz TV is a rebrand of something, there is no doubt about that. And yes, the Ken Rad 6sn7gt can oftentimes sound very dark and colored. With that in mind you may want to use some different output tubes, as the eh 6sn7 are probably one of the worst you can use IMO.

[nsuttitinagul]

I'll look into something else, but I'm reluctant to spend too much on tubes.

Given my budget and recent upgrades in my system, I won't be able to upgrade anything until January at earliest. I've heard that EH tubes aren't great, but when new they're quite nice; they just supposedly age/break down very quickly. With some luck, January won't be too far away for an upgrade.

[PFKMan23]

What amp are you using right now?

[tom_hankins]

I'm only running on some EH Gold 6SN7s for output, but I found the KenRad VT-231 a bit too warm and slow for my tastes when paired as such.

I'm using a Muntz TV 6SN7GTA as the input tube. I'm wondering if these tubes might have been relabeled or something because I can't find any information on them online.

I have had that effect when using all Kenrads but never when used in front of the Sylvanias. I tried the EH tubes for about an hour and stuck them back for a dire,dire,dire,dire,dire,dire, emergency.

[nsuttitinagul]

I'll try the Kenrad again as the input with two of the Muntz tubes as output. I recall these Muntz tubes as being detailed and airy but almost too bright when used with an EH input tube.

I haven't tried any combinations without EH tubes, so I'll see what I think.

[Frihed89]

If this is the case, the 6BX7-series of tubes on the high-power setting is calling your name. If even after listening to these (they're cheap, so pick up a pair) *then* perhaps the high-voltage setting isn't for you Or maybe a trio of '51 Hytrons

My MPX3 has a not-so-high voltage setting on it and it sounds wonderful with the 6BL7GT which on my other MPX3 SE with the standard high voltage setting sounded dark and surripy. I'd still look for a pair, as they're hard to find these days and worth trying (and hoarding).

I could never get the 7062 driving the 7119s to really work... it sounded like something was broken, so I quickly removed them

In addition to tkams idea, I'd try the 12bh7 (RCA or Brimar) driving a pair of Sylvania 5687s...

6BX7 tubes. Thanks. I haven't heard of these. The 6BL7GTAs are getting pricey.

I just wonder if my version of the MPX3 Slam SE isn't a bit different than some others. I have a number of upgrades, but not the Plitrons or the enormous rails, but i do have the Supra power supply. I wonder because: 1) The 6SN7GT on my rig is a fabulous output tube and I can drive it with almost anything in the 12A_7 family including the 12AT7 and its EU brothers 2) the 5687 and 7119 are also well driven by these same tubes. Oh, a possible exception: some 12BH7A (esp RCA long black plates) will work well as input to 6SN7GT and others won't. I get static. I don't know any electronics, so I am not sure why.

Anyway, it's good trading ideas. Thanks again for the tip on the 6BX7 series.

[Frihed89]

Muntz TV is a rebrand of something, there is no doubt about that. And yes, the Ken Rad 6sn7gt can oftentimes sound very dark and colored. With that in mind you may want to use some different output tubes, as the eh 6sn7 are probably one of the worst you can use IMO.

Right "Muntz" is rebranded and I am not familiar with it. Go to the tube mongers website and on it he has the NOS tubes pic library. Look on there if your model is a 6SN7GT.

[luvdunhill]

Thanks again for the tip on the 6BX7 series.

no problem! I bet you'll love 'em

[darkless]

I loved the 6BX7 output tubes on my old MPX3 SLAM XLR. I used 7N7 driver tubes, because I didn't want to pay the extravagant costs for good NOS 6SN7 tubes.

[tkam]

I always preferred the 6bx7 to the 6bl7's, the bx7s are more linear and cleaner sounding which is what I like in an output tube. I want the input tube to do the coloring not the output tubes.

[luvdunhill]

I always preferred the 6bx7 to the 6bl7's, the bx7s are more linear and cleaner sounding which is what I like in an output tube. I want the input tube to do the coloring not the output tubes.

I go back and forth I've owned three MPX3 SE and all sounded very different with these two tube families (three if you split the 6BL7GT/A). Seems like a solid recommendation considering Frihed89s preferences. One driver that definitely prefers the 6BL7GT/A tubes is the Amperex 7062. I can go either way on the 2c51.

[iceman94]

I always preferred the 6bx7 to the 6bl7's, the bx7s are more linear and cleaner sounding which is what I like in an output tube. I want the input tube to do the coloring not the output tubes.

x9

In my case (HD650s/SACDMods Sony 9100ES), I still stayed with a 6SN7 driver, my two favorite being the Sylvania 6SN7W short bottle and Mullard ECC32 coke bottle. I only tried the Raytheon 6414- it had great clarity, but was fatiguing and edgy. The Mullard was colored and midrangy, but nice every now and then.

Basically, the Sylvania 6SN7W + 6BX7 was so perfect for me I just didn't bother doing any more work. Frihed, YMMV, but you seem stuck on the 6SN7 too, so finding the *one* driver you like might be a good path for you.

[PaulB]

I recently purchased a pair of 396A's as output tube equivalences to 5687's on my MPX3 SE. Can I use the same 5687 adapters, or should I get a different set of adapters for the 396A's?

[iceman94]

396A is the Western Electric equivalent of the 2C51. This is typically used as a driver tube, not an output, and requires its own adapter. Don't use a 5687 adapter, they're not the same.